Characteristics of women undergoing repeat induced abortion

Background

Although repeat induced abortion is common, data concerning characteristics of women undergoing this procedure are lacking. We conducted this study to identify the characteristics, including history of physical abuse by a male partner and history of sexual abuse, of women who present for repeat induced abortion.

Methods

We surveyed a consecutive series of women presenting for initial or repeat pregnancy termination to a regional provider of abortion services for a wide geographic area in southwestern Ontario between August 1998 and May 1999. Self-reported demographic characteristics, attitudes and practices regarding contraception, history of relationship violence, history of sexual abuse or coercion, and related variables were assessed as potential correlates of repeat induced abortion. We used χ² tests for linear trend to examine characteristics of women undergoing a first, second, or third or subsequent abortion. We analyzed significant correlates of repeat abortion using stepwise multivariate multinomial logistic regression to identify factors uniquely associated with repeat abortion.

Results

Of the 1221 women approached, 1145 (93.8%) consented to participate. Data regarding first versus repeat abortion were available for 1127 women. A total of 68.2%, 23.1% and 8.7% of the women were seeking a first, second, or third or subsequent abortion respectively. Adjusted odds ratios for undergoing repeat versus a first abortion increased significantly with increased age (second abortion: 1.08, 95% confidence interval [CI] 1.04–1.09; third or subsequent abortion: 1.11, 95% CI 1.07–1.15), oral contraceptive use at the time of conception (second abortion: 2.17, 95% CI 1.52–3.09; third or subsequent abortion: 2.60, 95% CI 1.51–4.46), history of physical abuse by a male partner (second abortion: 2.04, 95% CI 1.39–3.01; third or subsequent abortion: 2.78, 95% CI 1.62–4.79), history of sexual abuse or violence (second abortion: 1.58, 95% CI 1.11–2.25; third or subsequent abortion: 2.53, 95% CI 1.50–4.28), history of sexually transmitted disease (second abortion: 1.50, 95% CI 0.98–2.29; third or subsequent abortion: 2.26, 95% CI 1.28–4.02) and being born outside Canada (second abortion: 1.83, 95% CI 1.19–2.79; third or subsequent abortion: 1.75, 95% CI 0.90–3.41).

Interpretation

Among other factors, a history of physical or sexual abuse was associated with repeat induced abortion. Presentation for repeat abortion may be an important indication to screen for a current or past history of relationship violence and sexual abuse.Repeat pregnancy termination procedures are common in Canada (where 35.5% of all induced abortions are repeat procedures)^1,2 and the United States (where 48% of induced abortions are repeat procedures).^3,4,5,6,7 Rates of repeat induced abortion increased in both countries for an initial period after abortion was legalized, as a result of an increase in the number of women who had access to a first, and consequently to repeat, legal induced abortion.^1,6,8,9 At present, rates of initial and repeat abortion in Canada and the United States appear to be stabilizing.^2,7Research concerning characteristics of women who undergo repeat induced abortions has been limited in scope. In a literature search we identified fewer than 20 studies in this area published over the past 3 decades. However, available research has shown several consistent findings. Women undergoing repeat abortions are more likely than those undergoing a first abortion to report using a method of contraception at the time of conception.^7,8,10,11 In addition, women seeking repeat abortions report more challenging family situations than women seeking initial abortions: they are more likely to be separated, divorced, widowed or living in a common-law marriage, and to report difficulties with their male partner.^1,5,8,11,12 They also are older,^7,13 have more children^1,5,13 and are more often non-white^7,11,13 than women seeking initial abortions.There is little evidence to suggest that women seeking repeat abortion are using pregnancy termination as a method of birth control.^1,5,6,8,11 Evidence also does not indicate that women seeking repeat abortion are psychologically maladjusted.^8,13Our literature review showed that many studies of repeat abortion are 20 to 30 years old and are based on data collected when abortion was a newly legalized procedure.^5,11 Furthermore, in studies of correlates of repeat abortion the investigators did not examine a range of personality characteristics that are known to influence women''s reproductive health outcomes,^14,15 including attitudes about sexuality,¹⁴ health locus of control,^16,17 degree of social integration,¹⁶ attitudes about contraception^18,19 and history of sexual or physical abuse.^20,21,22 The objective of the current study was to identify characteristics of women who undergo repeat induced abortion.     

Impact of patient communication problems on the risk of preventable adverse events in acute care settings

Background

Up to 50% of adverse events that occur in hospitals are preventable. Language barriers and disabilities that affect communication have been shown to decrease quality of care. We sought to assess whether communication problems are associated with an increased risk of preventable adverse events.

Methods

We randomly selected 20 general hospitals in the province of Quebec with at least 1500 annual admissions. Of the 145 672 admissions to the selected hospitals in 2000/01, we randomly selected and reviewed 2355 charts of patients aged 18 years or older. Reviewers abstracted patient characteristics, including communication problems, and details of hospital admission, and assessed the cause and preventability of identified adverse events. The primary outcome was adverse events.

Results

Of 217 adverse events, 63 (29%) were judged to be preventable, for an overall population rate of 2.7% (95% confidence interval [CI] 2.1%–3.4%). We found that patients with preventable adverse events were significantly more likely than those without such events to have a communication problem (odds ratio [OR] 3.00; 95% CI 1.43–6.27) or a psychiatric disorder (OR 2.35; 95% CI 1.09–5.05). Patients who were admitted urgently were significantly more likely than patients whose admissions were elective to experience an event (OR 1.64, 95% CI 1.07–2.52). Preventable adverse events were mainly due to drug errors (40%) or poor clinical management (32%). We found that patients with communication problems were more likely than patients without these problems to experience multiple preventable adverse events (46% v. 20%; p = 0.05).

Interpretation

Patients with communication problems appeared to be at highest risk for preventable adverse events. Interventions to reduce the risk for these patients need to be developed and evaluated.Patient safety is a priority in modern health care systems. From 3% to 17% of hospital admissions result in an adverse event,^1–8 and almost 50% of these events are considered to be preventable.^3,9–12 An adverse event is an unintended injury or complication caused by delivery of clinical care rather than by the patient''s condition. The occurrence of adverse events has been well documented; however, identifying modifiable risk factors that contribute to the occurrence of preventable adverse events is critical. Studies of preventable adverse events have focused on many factors, but researchers have only recently begun to evaluate the role of patient characteristics.^2,9,12,13 Older patients and those with a greater number of health problems have been shown to be at increased risk for preventable adverse events.^10,11 However, previous studies have repeatedly suggested the need to investigate more diverse, modifiable risk factors.^{3,6,7,10,11,14–16}Language barriers and disabilities that affect communication have been shown to decrease quality of care;^16–20 however, their impact on preventable adverse events needs to be investigated. Patients with physical and sensory disabilities, such as deafness and blindness, have been shown to face considerable barriers when communicating with health care professionals.^20–24 Communication disorders are estimated to affect 5%–10% of the general population,²⁵ and in one study more than 15% of admissions to university hospitals involved patients with 1 or more disabilities severe enough to prevent almost any form of communication.²⁶ In addition, patients with communication disabilities are already at increased risk for depression and other comorbidities.^27–29 Determining whether they are at increased risk for preventable adverse events would permit risk stratification at the time of admission and targeted preventive strategies.We sought to estimate the extent to which preventable adverse events that occurred in hospital could be predicted by conditions that affect a patient''s ability to communicate.     

Information exchange among physicians caring for the same patient in the community

Background

The exchange of information is an integral component of continuity of health care and may limit or prevent costly duplication of tests and treatments. This study determined the probability that patient information from previous visits with other physicians was available for a current physician visit.

Methods

We conducted a multicentre prospective cohort study including patients discharged from the medical or surgical services of 11 community and academic hospitals in Ontario. Patients included in the study saw at least 2 different physicians during the 6 months after discharge. The primary outcome was whether information from a previous visit with another physician was available at the current visit. We determined the availability of previous information using surveys of or interviews with the physicians seen during current visits.

Results

A total of 3250 patients, with a total of 39 469 previous–current visit combinations, met the inclusion criteria. Overall, information about the previous visit was available 22.0% of the time. Information was more likely to be available if the current doctor was a family physician (odds ratio [OR] 1.75, 95% confidence interval [CI] 1.54–1.98) or a physician who had treated the patient before the hospital admission (OR 1.33, 95% CI 1.21–1.46). Conversely, information was less likely to be available if the previous doctor was a family physician (OR 0.38, 95% CI 0.32–0.44) or a physician who had treated the patient before the admission (OR 0.72, 95% CI 0.60–0.86). The strongest predictor of information exchange was the current physician having previously received information about the patient from the previous physician (OR 7.72, 95% CI 6.92–8.63).

Interpretation

Health care information is often not shared among multiple physicians treating the same patient. This situation would be improved if information from family physicians and patients'' regular physicians was more systematically available to other physicians.Continuity of care occurs when patients experience linked care over time and when discrete elements of care are connected.¹ Overall, most studies have shown a benefit of physician continuity, exemplified by lower utilization of emergency and hospital services,^2–5 greater use of preventive interventions,^6–8 improvements in disease-specific symptoms or quality-of-care measures,⁹ and greater patient satisfaction.^10,11Continuity of care has been conceptualized as having 3 primary components:¹ physician continuity, management continuity and information continuity. The root component of information continuity is the availability of data from previous visits by the patient with other physicians. In 3 previous studies, physicians were frequently missing necessary information from visits that patients had made to other physicians.^12–14 However, none of those studies prospectively followed a well-defined cohort of patients.To achieve a better understanding of how information exchange might be improved in the community setting, we sought to identify the patient- and physician-related factors that influence the availability of information from previous visits with other physicians.     

Attitudes toward vaccination: a survey of Canadian chiropractic students

BackgroundAlthough the Canadian Chiropractic Association and the Canadian Memorial Chiropractic College (CMCC) endorse vaccination, the prevalence of anti-vaccination attitudes among Canadian chiropractors is unknown. This study describes the prevalence of anti-vaccination attitudes among Canadian chiropractic students.MethodsAn 11-item questionnaire about attitudes toward vaccination was distributed to students enrolled at CMCC during the 1999/2000 academic year. The responses for the 11 items were then summed to arrive at a total score ranging from 0 (most negative attitude toward vaccination) to 22 (most positive attitude toward vaccination). Respondents'' perceptions of sources of vaccine information were also investigated.ResultsOver 75% of the students (467 of 621) completed the questionnaire. Most students (53.3%) reported that in general they agreed with vaccination. This was especially true among first-year students (60.7%). However, among fourth year students, only 39.5% agreed with vaccination. The proportion of respondents who stated that they were against vaccination in general was 5 (4.5%) of 112 first-year students, 10 (8.3%) of 121 second-year students, 16 (13.9%) of 115 third-year students and 35 (29.4%) of 119 fourth-year students. The mean scores on the questionnaire were progressively lower with each higher year of study at the College. The mean survey scores for each year of study were first year, 15.9 (95% confidence interval [CI] 15.2–16.6); second year, 16.1 (95% CI 15.3–17.0); third year, 14.5 (95% CI 13.5–15.4); and fourth year, 12.8 (95% CI 11.7–13.9). The mean scores varied among year of study and were statistically significant using one-way ANOVA (p < 0.0001). Among students who relied primarily on informal sources of vaccine information, such as the chiropractic literature and informal talks at CMCC, anti-vaccination attitudes were more prevalent in later years. InterpretationMost CMCC students reported pro-vaccination attitudes, but there appeared to be an increase in anti-vaccination attitudes as students progressed through the CMCC program. This pattern was seen almost exclusively among students who relied primarily on informal sources of vaccine information rather than on core CMCC lectures or prior lectures at university. Chiropractic is the third-largest regulated health care profession in North America, after allopathic medicine and dentistry, and it is growing rapidly.^1,2 A 1997 Angus Reid poll revealed that 25% of all Canadians use, or have made use of, chiropractic.³ Additional studies have reported a substantial pediatric sample within this population.^4,5,6 Chiropractors are therefore likely to play an increasingly influential role in the formulation of societal perceptions on public health issues such as vaccination. Vaccination, however, remains a contentious issue for a vocal subpopulation of the Canadian chiropractic profession,^7,8,9 despite the positive official stance of the Canadian Chiropractic Association (CCA).¹⁰Currently there are approximately 5000 practising chiropractors in Canada, of whom 4000 are members of the CCA.¹¹ Furthermore, approximately 80% of Canadian chiropractors are graduates of the Canadian Memorial Chiropractic College (CMCC),⁶ the only English-language chiropractic college in Canada. It is possible that attitudes formed during the 4-year program at CMCC will be indicative of attitudes held by practising chiropractors.¹² This study reports the findings of a survey of students attending CMCC during the 1999/2000 academic year, which was designed to investigate their attitudes toward vaccination.     

Rate of elective cholecystectomy and the incidence of severe gallstone disease

Background

The use of elective cholecystectomy has increased dramatically following the widespread adoption of laparoscopic cholecystectomy. We sought to determine whether this increase has resulted in a reduction in the incidence of severe complications of gallstone disease.

Methods

We examined longitudinal trends in the population-based rates of severe gallstone disease from 1988 to 2000, using a quasi-experimental longitudinal design to assess the effects of the large increase in elective cholecystectomy rates after 1991 among people aged 18 years and older residing in Ontario. We also measured the rate of hospital admission because of acute diverticulitis, to control for secular trends in the use of hospital care for acute abdominal diseases.

Results

The adjusted annual rate of elective cholecystectomy per 100 000 population increased from 201.3 (95% confidence interval [CI] 197.0–205.8) in 1988–1990 to 260.8 (95% CI 257.1– 264.5) in 1992–2000 (rate ratio [RR] 1.35, 95% CI 1.32– 1.38, p 0.001). An anomalously high number of elective cholecystectomies were performed in 1991. Overall, the annual rate of severe gallstone diseases (acute cholecystitis, acute biliary pancreatitis and acute cholangitis) declined by 10% (RR 0.90, 95% CI 0.88– 0.91) for 1992–2000 as compared with 1988–1991. This decline was entirely due to an 18% reduction in the rate of acute cholecystitis (RR 0.82, 95% CI 0.80–0.84).

Interpretation

The increase in the rate of elective cholecystectomy that occurred following the introduction of laparoscopic cholecystectomy in 1991 was associated with an overall reduction in the incidence of severe gallstone disease that was entirely attributable to a reduction in the incidence of acute cholecystitis.After the widespread introduction of laparoscopic cholecystectomy in 1991, the rate of cholecystectomy in North America increased by 30% to 60%,^1,2,3 primarily because of higher rates of elective operations.¹ Although cholecystectomy is not ordinarily indicated in people with asymptomatic gallstones,^4,5 the decision to perform the procedure is highly discretionary.⁶ It is unclear whether the increased rate of elective cholecystectomy is due to overuse of surgery among people with asymptomatic or minimally symptomatic gallstones, or whether more patients with clinically important gallbladder disease are willing to undergo cholecystectomy with the availability of laparoscopic surgery.^7,8Most cholecystectomies are done in people with uncomplicated biliary colic, the most common presentation of symptomatic gallstones.⁸ Severe complications of gallbladder disease, such as acute cholecystitis, acute biliary pancreatitis and acute cholangitis, are potentially life-threatening conditions that require hospital care. Greater use of elective cholecystectomy in people at risk of severe gallstone complications should result in a lower incidence of such complications. We sought to determine whether the increase in the rate of elective cholecystectomy was associated with a reduction in the incidence of severe complications of gallbladder disease.     

Death and renal transplantation among Aboriginal people undergoing dialysis

Background

Despite the increase in the number of Aboriginal people with end-stage renal disease around the world, little is known about their health outcomes when undergoing renal replacement therapy. We evaluated differences in survival and rate of renal transplantation among Aboriginal and white patients after initiation of dialysis.

Methods

Adult patients who were Aboriginal or white and who commenced dialysis in Alberta, Saskatchewan or Manitoba between Jan. 1, 1990, and Dec. 31, 2000, were recruited for the study and were followed until death, transplantation, loss to follow-up or the end of the study (Dec. 31, 2001). We used Cox proportional hazards models to examine the effect of race on patient survival and likelihood of transplant, with adjustment for potential confounders.

Results

Of the 4333 adults who commenced dialysis during the study period, 15.8% were Aboriginal and 72.4% were white. Unadjusted rates of death per 1000 patient-years during the study period were 158 (95% confidence interval [CI] 144–176) for Aboriginal patients and 146 (95% CI 139–153) for white patients. When follow-up was censored at the time of transplantation, the age-adjusted risk of death after initiation of dialysis was significantly higher among Aboriginal patients than among white patients (hazard ratio [HR] 1.15, 95% CI 1.02–1.30). The greater risk of death associated with Aboriginal race was no longer observed after adjustment for diabetes mellitus and other comorbid conditions (adjusted HR 0.89, 95% CI 0.77–1.02) and did not appear to be associated with socioeconomic status. During the study period, unadjusted transplantation rates per 1000 patient-years were 62 (95% CI 52–75) for Aboriginal patients and 133 (95% CI 125–142) for white patients. Aboriginal patients were significantly less likely to receive a renal transplant after commencing dialysis, even after adjustment for potential confounders (HR 0.43, 95% CI 0.35–0.53). In an additional analysis that included follow-up after transplantation for those who received renal allografts, the age-adjusted risk of death associated with Aboriginal race (HR 1.36, 95% CI 1.21–1.52) was higher than when follow-up after transplantation was not considered, perhaps because of the lower rate of transplantation among Aboriginals.

Interpretation

Survival among dialysis patients was similar for Aboriginal and white patients after adjustment for comorbidity. However, despite universal access to health care, Aboriginal people had a significantly lower rate of renal transplantation, which might have adversely affected their survival when receiving renal replacement therapy.In North America and the Antipodes, the incidence of diabetes among adolescent and adult Aboriginals has risen dramatically,^1,2,3,4 with corresponding increases in the prevalence of diabetic nephropathy.^5,6,7 Aboriginal people in Canada have experienced disproportionately high incidence rates of end-stage renal disease (ESRD), with an 8-fold increase in the number of prevalent dialysis patients between 1980 and 2000.⁸ Although the incidence of ESRD appears to have decreased in recent years, the prevalence of diabetes mellitus and its complications are rising, especially among young people.^9,10,11Most work evaluating health outcomes among Aboriginal people considers either the general population¹²or diseases for which interventions are implemented over a short period, such as alcohol abuse,¹³ injury¹⁴ or critical illness.¹⁵ Death and markers of poor health are significantly more common among Aboriginal people than among North Americans of European ancestry, perhaps because of the greater prevalence of diabetes mellitus, adverse health effects due to lower socioeconomic status¹⁶ and reduced access to primary care.¹⁷ Aboriginal patients may also face unique barriers to care, including mistrust of non-Aboriginal providers, institutional discrimination or preference for traditional remedies.¹⁸ These factors may be most relevant when contact with physicians is infrequent, which obstructs development of a therapeutic relationship. In contrast, ESRD is a chronic illness that requires ongoing care from a relatively small, stable multidisciplinary team.Although recent evidence highlights racial inequalities in morbidity and mortality among North Americans with ESRD, most studies have focused on black or Hispanic populations.¹⁹We conducted this study to evaluate rates of death and renal transplantation among Aboriginal people after initiation of dialysis in Alberta, Saskatchewan and Manitoba.     

The effect of safer play equipment on playground injury rates among school children

Background

Changes to Canadian Standards Association (CSA) standards for playground equipment prompted the removal of hazardous equipment from 136 elementary schools in Toronto. We conducted a study to determine whether applying these new standards and replacing unsafe playground equipment with safe equipment reduced the number of school playground injuries.

Methods

A total of 86 of the 136 schools with hazardous play equipment had the equipment removed and replaced with safer equipment within the study period (intervention schools). Playground injury rates before and after equipment replacement were compared in intervention schools. A database of incident reports from the Ontario School Board Insurance Exchange was used to identify injury events. There were 225 schools whose equipment did not require replacement (nonintervention schools); these schools served as a natural control group for background injury rates during the study period. Injury rates per 1000 students per month, relative risks (RRs) and 95% confidence intervals (CIs) were calculated, adjusting for clustering within schools.

Results

The rate of injury in intervention schools decreased from 2.61 (95% CI 1.93–3.29) per 1000 students per month before unsafe equipment was removed to 1.68 (95% CI 1.31–2.05) after it was replaced (RR 0.70, 95% CI 0.62–0.78). This translated into 550 injuries avoided in the post-intervention period. In nonintervention schools, the rate of injury increased from 1.44 (95% CI 1.07–1.81) to 1.81 (95% CI 1.07–2.53) during the study period (RR 1.40, 95% CI 1.29–1.52).

Interpretation

The CSA standards were an effective tool in identifying hazardous playground equipment. Removing and replacing unsafe equipment is an effective strategy for preventing playground injuries.Playgrounds provide a recreational refuge for children, away from traffic and other outdoor hazards. In addition, playground activities can enhance children''s cognitive, physical and psychosocial skills. Playground safety is of concern to physicians, parents and injury prevention advocates. Of all playground injuries that result in a visit to a hospital emergency department, 27%–40% are fractures and 17% require hospital admission — a greater frequency of admission than that associated with any other cause of pediatric injury except traffic.^1,2,3,4 The results of an observational study in Wales showed that 90% of all playground injuries resulting in a visit to an emergency department were related to the playground equipment.¹ As might be expected, playgrounds are the location within elementary schools with the highest injury rates and the most severe injuries.⁵ In a study conducted in Kingston, Ont., children were 12 times more likely to be injured in school playgrounds than in municipal playgrounds.³Standards for playgrounds have been developed both in Canada⁶ and internationally.^{7,8,9,10,11,12} The Canadian Standards Association (CSA) standards for the design, installation and maintenance of playgrounds and equipment were most recently revised in 1998.⁶ No published data exist on the relation between equipment standards and injury rates. If applying standards can identify unsafe playgrounds and, more importantly, reduce the rate of child injury, such standards would be a useful tool for school and municipal authorities responsible for playgrounds.We sought to determine the effect of replacing unsafe playground equipment (as determined using the new CSA standards) on injury rates among school children.     

Fluoroquinolones compared with β-lactam antibiotics for the treatment of acute bacterial sinusitis: a meta-analysis of randomized controlled trials

Background

The presumed superiority of newer fluoroquinolones for the treatment of acute bacterial sinusitis is based on laboratory data but has not yet been established on clinical grounds.

Methods

We performed a meta-analysis of randomized controlled trials comparing the effectiveness and safety of fluoroquinolones and β-lactams in acute bacterial sinusitis.

Results

We identified 8 randomized controlled trials investigating the newer “respiratory” fluoroquinolones moxifloxacin, levofloxacin and gatifloxacin. In the primary effectiveness analysis involving 2133 intention-to-treat patients from 5 randomized controlled trials, the extent of clinical cure and improvement did not differ between fluoroquinolones and β-lactams (odds ratio [OR] 1.09, 95% confidence interval [CI] 0.85–1.39) at the test-of-cure assessment, which varied from 10 to 31 days after the start of treatment. Fluoroquinolones were associated with an increased chance of clinical success among the clinically evaluable patients in all of the randomized controlled trials (OR 1.29, 95% CI 1.03–1.63) and in 4 blinded randomized controlled trials (OR 1.45, 95% CI 1.05–2.00). There was no statistically significant difference between fluoroquinolones and amoxicillin–clavulanate (OR 1.24, 95% CI 0.93–1.65). Eradication or presumed eradication of the pathogens isolated before treatment was more likely with fluoroquinolone treatment than with β-lactam treatment (OR 2.11, 95% CI 1.09–4.08). In the primary safety analysis, adverse events did not differ between treatments (OR 1.17, 95% CI 0.86–1.59). However, more adverse events occurred with fluoroquinolone use than with β-lactam use in 2 blinded randomized controlled trials. The associations described here were generally consistent when we included 3 additional studies involving other fluoroquinolones (ciprofloxacin and sparfloxacin) in the analysis.

Interpretation

In the treatment of acute bacterial sinusitis, newer fluoroquinolones conferred no benefit over β-lactam antibiotics. The use of fluoroquinolones as first-line therapy cannot be endorsed.Acute bacterial sinusitis (more accurately known as rhinosinusitis, given that the nasal mucosa is commonly involved¹) is one of the most frequent health disorders;² it has an adverse impact on patients'' quality of life³ and accounts for nearly 3 million ambulatory care visits in the United States annually⁴ and substantial health care costs.⁵Acute bacterial sinusitis typically follows an episode of viral upper respiratory tract illness.² The diagnosis of bacterial disease in routine clinical practice is usually based on the presence of a constellation of clinical manifestations.¹ The bacterial pathogens most commonly involved are Streptococcus pneumoniae, Haemophilus influenzae and, to a lesser degree, Moraxella catarrhalis.^6,7 Over the years, these pathogens have acquired various degrees of resistance to many traditional antibiotics.⁸The benefit of older antibiotics over placebo in the treatment of acute bacterial sinusitis appears limited, mostly because of the high success rate achieved with placebo.^9,10 However, newer, third-and fourth-generation fluoroquinolones possess excellent in vitro activity against the most common respiratory pathogens,¹¹ and for this reason these drugs are often designated as “respiratory.” Based on analysis of the available laboratory data, current guidelines give the newer fluoroquinolones the highest ranking, in terms of expected clinical effectiveness, among the antimicrobials used to treat acute bacterial sinusitis (although admittedly the difference is marginal).⁷The presumed clinical advantage of the respiratory fluoroquinolones over other classes of antimicrobials has not been clearly demonstrated in comparative clinical trials or meta-analyses.^9,10 We aimed to comprehensively reassess the role of fluoroquinolones in the treatment of acute bacterial sinusitis, in terms of effectiveness and safety, by performing a meta-analysis of relevant randomized controlled trials.     

Breast size and risk of type 2 diabetes mellitus

Background

Elevated waist circumference and body mass index (BMI), both traditional measures of obesity, are accepted risk factors for type 2 diabetes mellitus. Girls who are obese experience earlier onset of puberty and possibly greater breast development. We sought to evaluate whether a woman''s breast size in late adolescence is associated with an increased risk of type 2 diabetes mellitus in adulthood.

Methods

In conjunction with the ongoing Nurses'' Health Study II, which began to study risk factors for breast cancer among women in 1989, we conducted a prospective cohort study involving 92 106 of the participants. We assessed the risk of type 2 diabetes mellitus in relation to self-reported bra cup sizes, categorized as ≤ A, B, C and ≥ D cups, among participants at age 20.

Results

The mean age of participants at baseline was 38.1 years. A total of 1844 new cases of type 2 diabetes mellitus arose at a mean age of 44.9 years during 886 443 person-years of follow-up. Relative to bra cup size ≤ A, the respective age-adjusted hazard ratios (and 95% confidence intervals [CIs]) were 2.30 (1.99–2.66) for B cup, 4.32 (3.71–5.04) for C cup and 4.99 (4.12–6.05) for ≥ D cup. Upon further adjustments for age at menarche, parity, physical activity, smoking status, diet, multivitamin use, family history of diabetes mellitus, BMI at age 18 and current BMI, the corresponding hazard ratios (and 95% CIs) were 1.37 (1.18–1.59) for B cup, 1.80 (1.53- 2.11) for C cup and 1.64 (1.34–2.01) for ≥ D cup. The addition of waist circumference to this model minimally changed the hazard ratios (and 95% CIs): 1.32 (1.14–1.53) for B cup, 1.71 (1.46–2.01) for C cup and 1.58 (1.29–1.94) for ≥ D cup.

Interpretation

A large bra cup size at age 20 may be a predictor of type 2 diabetes mellitus in middle-aged women. Whether this relation is independent of traditional indicators of obesity remains to be determined.Obesity is an established risk factor for type 2 diabetes mellitus.^1,2 Affected individuals show signs of insulin resistance and hyperinsulinemia, a process that may begin in childhood.^3,4 Pre-adolescent obesity is also an important predictor of age of onset of breast development in young women, and of breast size after puberty.^5,6 Premature onset of puberty is preceded by childhood insulin resistance, hyperinsulinemia and hyperandrogenemia,⁷ which may persist after puberty⁸ and continue into early adulthood.⁹Although an elevated body mass index (BMI)^10,11 and central adiposity¹² are established risk factors for insulin resistance and the onset of type 2 diabetes mellitus, little is known about the contribution of extra-abdominal adipose tissue, including breast tissue, about 60% of which is fatty tissue, to this process.^13,14 We hypothesized that a woman''s breast size in late adolescence reflects her predisposition to insulin resistance and type 2 diabetes mellitus that is both additive to, and independent of, BMI. We explored this hypothesis in conjunction with the Nurses'' Health Study II by relating bra cup size, a proxy for breast size, to the onset of type 2 diabetes mellitus.     

Effectiveness of sucrose analgesia in newborns undergoing painful medical procedures

Background

Sucrose is widely used to manage procedural pain in term newborns despite a lack of evidence of its effectiveness for different procedures and infant populations. Our objectives were to evaluate the effectiveness and safety of sucrose in newborns undergoing various medical procedures within 2 days of birth.

Methods

We performed a double-blind, randomized controlled trial. We included newborns (≥ 36 weeks gestation) of diabetic mothers and nondiabetic mothers. Each newborn received 2 mL of a 24%-sucrose or placebo solution before all procedures. We used the Premature Infant Pain Profile to assess pain during intramuscular injection of vitamin K, venipuncture for the newborn screening test and the first 3 heel lances for glucose monitoring (newborns of diabetic mothers only). Scores ranged from from 0 (no pain) to 18 (maximum pain).

Results

We included 240 newborns (120 from diabetic mothers, 120 from nondiabetic mothers). The overall mean pain score was lower among newborns who received sucrose than among those who received a placebo (mean difference –1.3, 95% confidence interval [CI] –2.0 to –0.6). We found that pain scores during intramuscular injection did not differ significantly between the sucrose and placebo groups for newborns of diabetic or nondiabetic mothers (newborns of nondiabetic mothers: mean difference –1.1, 95% CI –2.4 to 0.2; newborns of diabetic mothers: mean difference –1.0, 95% CI –2.4 to 0.4). During venipuncture, newborns who received sucrose had lower pain scores compared with those who received a placebo (newborns of nondiabetic mothers: mean difference –3.2, 95% CI –4.6 to –1.8; newborns of diabetic mothers: mean difference –2.4, 95% CI –3.8 to –1.0). Among newborns of diabetic mothers, there was no difference in pain during the first 3 heel lances or mean glucose levels between the sucrose and placebo groups (p = 0.94 and p = 0.29 respectively).

Interpretation

We found a modest reduction of pain in newborns of both diabetic and nondiabetic mothers when sucrose was used for all medical procedures performed in the first 2 days after birth. However, when each procedure was analyzed separately, we found that the effectiveness of sucrose was limited to venipuncture for the newborn screening test. (http://Clinicaltrials.gov trial register no. {"type":"clinical-trial","attrs":{"text":"NCT00213213","term_id":"NCT00213213"}}NCT00213213.)All newborns experience pain from medical procedures in the first days after birth. At the very least, newborns receive an intramuscular injection of vitamin K and venipuncture or heel-lance for newborn screening tests. Newborns of diabetic mothers, about 4% of newborns, undergo additional heel-lances for monitoring glucose levels.^1,2 Untreated pain from these procedures can have long-lasting effects.^3,4 We previously reported that newborns of diabetic mothers who received an average of 10 heel-lances within 2 days of birth exhibited a heightened pain response during subsequent venipunctures compared with newborns from nondiabetic mothers.²Studies aimed at reducing pain and its consequences in newborns are clinically important.^5–7 Sucrose (table sugar) has great potential for routine use.⁶ Sucrose is a naturally occurring sweetener with analgesic effects in newborns. Although not fully understood, the mechanism of action is thought to involve activation of the endogenous opioid system through taste.⁸ This is supported by the presence of opioid receptors on the tongue and animal studies showing that analgesia can be reversed by opioid antagonists during noxious stimulation.⁹ Moreover, chronic consumption of sweeteners has been shown to negate the analgesic effects of opioids.¹⁰In systematic reviews, single doses of sucrose have been reported to reduce pain in newborns undergoing commonly performed medical procedures, including heel-lancing and venipuncture.^11,12 Based on these data, national and international pain management guidelines promote the widespread use of sucrose.^13–16 However, sucrose has not been evaluated for all commonly performed procedures in healthy term newborns, and there are concerns that sucrose may raise blood glucose levels in newborns of diabetic mothers. It is necessary to demonstrate that sucrose is effective and safe for varied procedures, repeated use and diverse infant populations.We sought to evaluate the effectiveness and safety of sucrose in newborns of diabetic mothers and nondiabetic mothers undergoing routine painful medical procedures during the first 2 days after birth. Our hypothesis was that sucrose reduces pain during intramuscular injection of vitamin K, venipuncture for the newborn screening test and heel lance for blood glucose monitoring without serious adverse effects.     

Efficacy and safety of insulin analogues for the management of diabetes mellitus: a meta-analysis

Background

Although insulin analogues are commonly prescribed for the management of diabetes mellitus, there is uncertainty regarding their optimal use. We conducted meta-analyses to compare the outcomes of insulin analogues with conventional insulins in the treatment of type 1, type 2 and gestational diabetes.

Methods

We updated 2 earlier systematic reviews of the efficacy and safety of rapid-and long-acting insulin analogues. We searched electronic databases, conference proceedings and “grey literature” up to April 2007 to identify randomized controlled trials that compared insulin analogues with conventional insulins. Study populations of interest were people with type 1 and type 2 diabetes (adult and pediatric) and women with gestational diabetes.

Results

We included 68 randomized controlled trials in the analysis of rapid-acting insulin analogues and 49 in the analysis of long-acting insulin analogues. Most of the studies were of short to medium duration and of low quality. In terms of hemoglobin A_1c, we found minimal differences between rapid-acting insulin analogues and regular human insulin in adults with type 1 diabetes (weighted mean difference for insulin lispro: –0.09%, 95% confidence interval [CI] –0.16% to –0.02%; for insulin aspart: –0.13%, 95% CI –0.20% to –0.07%). We observed similar outcomes among patients with type 2 diabetes (weighted mean difference for insulin lispro: –0.03%, 95% CI –0.12% to –0.06%; for insulin aspart: –0.09%, 95% CI –0.21% to 0.04%). Differences between long-acting insulin analogues and neutral protamine Hagedorn insulin in terms of hemoglobin A_1c were marginal among adults with type 1 diabetes (weighted mean difference for insulin glargine: –0.11%, 95% CI –0.21% to –0.02%; for insulin detemir: –0.06%, 95% CI –0.13% to 0.02%) and among adults with type 2 diabetes (weighted mean difference for insulin glargine: –0.05%, 95% CI –0.13% to 0.04%; for insulin detemir: 0.13%, 95% CI 0.03% to 0.22%). Benefits in terms of reduced hypoglycemia were inconsistent. There were insufficient data to determine whether insulin analogues are better than conventional insulins in reducing long-term diabetes-related complications or death.

Interpretation

Rapid-and long-acting insulin analogues offer little benefit relative to conventional insulins in terms of glycemic control or reduced hypoglycemia. Long-term, high-quality studies are needed to determine whether insulin analogues reduce the risk of long-term complications of diabetes.Diabetes mellitus is associated with serious long-term complications and premature death.¹ Data from the Health Canada National Diabetes Surveillance System indicate that, in 2004/05, diabetes was diagnosed in about 5.5% (1.8 million) of Canadians aged 20 years and older.² Because the disease goes undetected in many cases, the true prevalence may approach 1.9 million.³Tight glycemic control, to maintain a hemoglobin A_1c concentration of 7.0% or less, is recommended for all patients with diabetes to reduce the risk of long-term complications such as cardiovascular-related death, retinopathy and nephropathy.⁴ Insulin is indicated for all patients with type 1 diabetes and for patients with type 2 diabetes if adequate glycemic control cannot be achieved through exercise, diet or oral antidiabetic therapy.⁴Conventional insulins include regular human insulin and intermediate-acting neutral protamine Hagedorn insulin. However, these agents do not replicate the pattern of basal and postprandial endogenous secretion of insulin. Insulin analogues are modified human insulins developed to address this limitation.⁵ The rapid-acting insulin analogues insulin lispro, insulin aspart and insulin glulisine are marketed in Canada as bolus insulins; the long-acting agents insulin glargine and insulin detemir are marketed as basal insulins.⁶Systematic reviews of the insulin analogues have been published previously.^7–10 However, through our comprehensive search of the literature, we did not identify any reviews of long-acting insulin analogues in the management of type 1 diabetes or gestational diabetes. In this article, we provide an up-to-date, comprehensive systematic review and meta-analysis of outcomes associated with the use of rapid-and long-acting insulin analogues in type 1 and type 2 diabetes (adult and pediatric patients) and gestational diabetes. Detailed methods and complete results are reported elsewhere.^11,12     

Identifying unprovoked thromboembolism patients at low risk for recurrence who can discontinue anticoagulant therapy

Background

Whether to continue oral anticoagulant therapy beyond 6 months after an “unprovoked” venous thromboembolism is controversial. We sought to determine clinical predictors to identify patients who are at low risk of recurrent venous thromboembolism who could safely discontinue oral anticoagulants.

Methods

In a multicentre prospective cohort study, 646 participants with a first, unprovoked major venous thromboembolism were enrolled over a 4-year period. Of these, 600 participants completed a mean 18-month follow-up in September 2006. We collected data for 69 potential predictors of recurrent venous thromboembolism while patients were taking oral anticoagulation therapy (5–7 months after initiation). During follow-up after discontinuing oral anticoagulation therapy, all episodes of suspected recurrent venous thromboembolism were independently adjudicated. We performed a multivariable analysis of predictor variables (p < 0.10) with high interobserver reliability to derive a clinical decision rule.

Results

We identified 91 confirmed episodes of recurrent venous thromboembolism during follow-up after discontinuing oral anticoagulation therapy (annual risk 9.3%, 95% CI 7.7%–11.3%). Men had a 13.7% (95% CI 10.8%–17.0%) annual risk. There was no combination of clinical predictors that satisfied our criteria for identifying a low-risk subgroup of men. Fifty-two percent of women had 0 or 1 of the following characteristics: hyperpigmentation, edema or redness of either leg; D-dimer ≥ 250 μg/L while taking warfarin; body mass index ≥ 30 kg/m²; or age ≥ 65 years. These women had an annual risk of 1.6% (95% CI 0.3%–4.6%). Women who had 2 or more of these findings had an annual risk of 14.1% (95% CI 10.9%–17.3%).

Interpretation

Women with 0 or 1 risk factor may safely discontinue oral anticoagulant therapy after 6 months of therapy following a first unprovoked venous thromboembolism. This criterion does not apply to men. (http://Clinicaltrials.gov trial register number {"type":"clinical-trial","attrs":{"text":"NCT00261014","term_id":"NCT00261014"}}NCT00261014)Venous thromboembolism is a common, potentially fatal, yet treatable, condition. The risk of a recurrent venous thromboembolic event after 3–6 months of oral anticoagulant therapy varies. Some groups of patients (e.g., those who had a venous thromboembolism after surgery) have a very low annual risk of recurrence (< 1%),¹ and they can safely discontinue anticoagulant therapy.² However, among patients with an unprovoked thromboembolism who discontine anticoagulation therapy after 3–6 months, the risk of a recurrence in the first year is 5%–27%.^3–6 In the second year, the risk is estimated to be 5%,³ and it is estimated to be 2%–3.8% for each subsequent year.^5,7 The case-fatality rate for recurrent venous thromboembolism is between 5% and 13%.^8,9 Oral anticoagulation therapy is very effective for reducing the risk of recurrence during therapy (> 90% relative risk [RR] reduction);^3,4,10,11 however, this benefit is lost after therapy is discontinued.^3,10,11 The risk of major bleeding with ongoing oral anticoagulation therapy among venous thromboembolism patients is 0.9–3.0% per year,^3,4,6,12 with an estimated case-fatality rate of 13%.¹³Given that the long-term risk of fatal hemorrhage appears to balance the risk of fatal recurrent pulmonary embolism among patients with an unprovoked venous thromboembolism, clinicians are unsure if continuing oral anticoagulation therapy beyond 6 months is necessary.^2,14 Identifying subgroups of patients with an annual risk of less than 3% will help clinicians decide which patients can safely discontinue anticoagulant therapy.We sought to determine the clinical predictors or combinations of predictors that identify patients with an annual risk of venous thromboembolism of less than 3% after taking an oral anticoagulant for 5–7 months after a first unprovoked event.     

Access to health care among status Aboriginal people with chronic kidney disease

Background

Ethnic disparities in access to health care and health outcomes are well documented. It is unclear whether similar differences exist between Aboriginal and non-Aboriginal people with chronic kidney disease in Canada. We determined whether access to care differed between status Aboriginal people (Aboriginal people registered under the federal Indian Act) and non-Aboriginal people with chronic kidney disease.

Methods

We identified 106 511 non-Aboriginal and 1182 Aboriginal patients with chronic kidney disease (estimated glomerular filtration rate less than 60 mL/min/1.73 m²). We compared outcomes, including hospital admissions, that may have been preventable with appropriate outpatient care (ambulatory-care–sensitive conditions) as well as use of specialist services, including visits to nephrologists and general internists.

Results

Aboriginal people were almost twice as likely as non-Aboriginal people to be admitted to hospital for an ambulatory-care–sensitive condition (rate ratio 1.77, 95% confidence interval [CI] 1.46–2.13). Aboriginal people with severe chronic kidney disease (estimated glomerular filtration rate < 30 mL/min/1.73 m²) were 43% less likely than non-Aboriginal people with severe chronic kidney disease to visit a nephrologist (hazard ratio 0.57, 95% CI 0.39–0.83). There was no difference in the likelihood of visiting a general internist (hazard ratio 1.00, 95% CI 0.83–1.21).

Interpretation

Increased rates of hospital admissions for ambulatory-care–sensitive conditions and a reduced likelihood of nephrology visits suggest potential inequities in care among status Aboriginal people with chronic kidney disease. The extent to which this may contribute to the higher rate of kidney failure in this population requires further exploration.Ethnic disparities in access to health care are well documented;^1,2 however, the majority of studies include black and Hispanic populations in the United States. The poorer health status and increased mortality among Aboriginal populations than among non-Aboriginal populations,^3,4 particularly among those with chronic medical conditions,^5,6 raise the question as to whether there is differential access to health care and management of chronic medical conditions in this population.The prevalence of end-stage renal disease, which commonly results from chronic kidney disease, is about twice as common among Aboriginal people as it is among non-Aboriginal people.^7,8 Given that the progression of chronic kidney disease can be delayed by appropriate therapeutic interventions^9,10 and that delayed referral to specialist care is associated with increased mortality,^11,12 issues such as access to health care may be particularly important in the Aboriginal population. Although previous studies have suggested that there is decreased access to primary and specialist care in the Aboriginal population,^13–15 these studies are limited by the inclusion of patients from a single geographically isolated region,¹³ the use of survey data,¹⁴ and the inability to differentiate between different types of specialists and reasons for the visit.¹⁵In addition to physician visits, admission to hospital for ambulatory-care–sensitive conditions (conditions that, if managed effectively in an outpatient setting, do not typically result in admission to hospital) has been used as a measure of access to appropriate outpatient care.^16,17 Thus, admission to hospital for an ambulatory-care–sensitive condition reflects a potentially preventable complication resulting from inadequate access to care. Our objective was to determine whether access to health care differs between status Aboriginal (Aboriginal people registered under the federal Indian Act) and non-Aboriginal people with chronic kidney disease. We assess differences in care by 2 measures: admission to hospital for an ambulatory-care–sensitive condition related to chronic kidney disease; and receipt of nephrology care for severe chronic kidney disease as recommended by clinical practice guidelines.¹⁸     

The effect of traumatic brain injury on the health of homeless people

Background

We sought to determine the lifetime prevalence of traumatic brain injury and its association with current health conditions in a representative sample of homeless people in Toronto, Ontario.

Methods

We surveyed 601 men and 303 women at homeless shelters and meal programs in 2004–2005 (response rate 76%). We defined traumatic brain injury as any self-reported head injury that left the person dazed, confused, disoriented or unconscious. Injuries resulting in unconsciousness lasting 30 minutes or longer were defined as moderate or severe. We assessed mental health, alcohol and drug problems in the past 30 days using the Addiction Severity Index. Physical and mental health status was assessed using the SF-12 health survey. We examined associations between traumatic brain injury and health conditions.

Results

The lifetime prevalence among homeless participants was 53% for any traumatic brain injury and 12% for moderate or severe traumatic brain injury. For 70% of respondents, their first traumatic brain injury occurred before the onset of homelessness. After adjustment for demographic characteristics and lifetime duration of homelessness, a history of moderate or severe traumatic brain injury was associated with significantly increased likelihood of seizures (odds ratio [OR] 3.2, 95% confidence interval [CI] 1.8 to 5.6), mental health problems (OR 2.5, 95% CI 1.5 to 4.1), drug problems (OR 1.6, 95% CI 1.1 to 2.5), poorer physical health status (–8.3 points, 95% CI –11.1 to –5.5) and poorer mental health status (–6.0 points, 95% CI –8.3 to –3.7).

Interpretation

Prior traumatic brain injury is very common among homeless people and is associated with poorer health.Traumatic brain injury is caused by “a blow or jolt to the head or a penetrating head injury that disrupts the normal function of the brain” and most commonly results from falls, motor vehicle traffic crashes and assaults.¹ Traumatic brain injury is a leading cause of permanent disability in North America.¹ Traumatic brain injury may be common in the homeless population.² Exposure to physical abuse during childhood, which could result in traumatic brain injury, is a known risk factor for homelessness as an adult.³ Substance abuse increases the risk of homelessness⁴ and the risk of traumatic brain injury.⁵ Homeless people experience high rates of injury of all types and are frequently victims of assault.^6,7 Finally, traumatic brain injury could be a factor contributing to the 3%–8% prevalence of cognitive dysfunction among homeless adults.^8,9Providing health care for homeless patients can be challenging for various reasons, including difficult behavioural patterns. These behaviours may be related in part to unrecognized sequelae of traumatic brain injury and may include cognitive impairment, attention deficits, disinhibition, impulsivity and emotional lability.¹ Appropriate support services may be able to minimize the adverse impact of these behaviours.Two previous studies have reported the prevalence of traumatic brain injury among homeless people in London, England, and Milwaukee, Wisconsin. These studies were limited by small sample sizes, recruitment at a single shelter and a lack of data from women.^10,11 We conducted this study to determine the lifetime prevalence of traumatic brain injury in a representative sample of homeless men and women across an entire city, and to identify the temporal relation between traumatic brain injury and the onset of homelessness. We also sought to characterize the association between a history of traumatic brain injury and current health problems in this population. Our primary hypothesis was that a history of traumatic brain injury would be associated with poor current health.     

Early risk of stroke after a transient ischemic attack in patients with internal carotid artery disease

BackgroundTransient ischemic attacks (TIAs) often herald a stroke, but little is known about the acute natural history of TIAs. Our objective was to quantify the early risk of stroke after a TIA in patients with internal carotid artery disease.MethodsUsing patient data from the medical arm of the North American Symptomatic Carotid Endarterectomy Trial, we calculated the risk of ipsilateral stroke in the territory of the symptomatic internal carotid artery within 2 and 90 days after a first-recorded hemispheric TIA. We also studied similar outcomes among patients in the trial who had a first-recorded completed hemispheric stroke.ResultsFor patients with a first-recorded hemispheric TIA (n = 603), the 90-day risk of ipsilateral stroke was 20.1% (95% confidence interval [CI] 17.0%–23.2%), higher than the 2.3% risk (95% CI 1.0%–3.6%) for patients with a hemispheric stroke (n = 526). The 2-day risks were 5.5% and 0.0%, respectively. Patients with more severe stenosis of the internal carotid artery (> 70%) appeared to be at no greater risk of stroke than patients with lesser degrees of stenosis (adjusted hazard ratio 1.1, 95% CI 0.7–1.7). Infarct on brain imaging (adjusted hazard ratio 2.1, 95% CI 1.5–3.0) and the presence of intracranial major-artery disease (adjusted hazard ratio 1.9, 95% CI 1.3-2.7) doubled the early risk of stroke in patients with a hemispheric TIA.InterpretationPatients who had a hemispheric TIA related to internal carotid artery disease had a high risk of stroke in the first few days after the TIA. Early risk of stroke was not affected by the degree of internal carotid artery stenosis.A transient ischemic attack (TIA) is a common neurological condition that is seen by all physician groups including family and emergency physicians, internists, vascular surgeons, and neurologists. In Canada, half a million adults aged 18 and over have been diagnosed with a TIA.¹ Presenting symptoms vary depending on which arterial supply is compromised, but they commonly consist of a brief episode of weakness, numbness, loss of vision or speech difficulty with complete recovery.Atherosclerotic disease of the carotid arteries outside the cranial cavity has long been recognized as the most common source of emboli that then travel to the brain causing stroke.^2,3,4 TIAs are often early warning signs of atherosclerotic disease. About 10% of patients with a TIA presenting to California emergency departments returned to the emergency department with a stroke within 90 days.⁵ In half of the patients, the stroke occurred within the first 48 hours after the TIA. Similar 90-day results have been observed in earlier community-based studies.^6,7,8 However, these studies all included some patients who had emboli from heart lesions or arrhythmias and some patients who had small-vessel disease as a cause of their TIA.Although several large stroke-prevention trials among patients with TIAs^{9,10,11,12,13,14,15,16,17,18} have presented some data on the risk of stroke from pre-existing atherosclerotic disease of the carotid arteries, they are limited because enrolment in the trials was delayed by 1 or more months after the TIA occurred. Small case series^19,20 have examined the relation between carotid artery disease and TIA, but without assessment of stroke outcome. Thus, the influence of atherosclerotic disease in the carotid artery on early stroke occurrence among people presenting with a TIA has not been assessed in any large study.²¹Using patients from the medical arm of the North American Symptomatic Carotid Endarterectomy Trial (NASCET), we describe the early risk of stroke in a large number of patients with a TIA in whom internal carotid artery disease was the only presumed cause.     

Effect of ambient air pollution on the incidence of appendicitis

Background

The pathogenesis of appendicitis is unclear. We evaluated whether exposure to air pollution was associated with an increased incidence of appendicitis.

Methods

We identified 5191 adults who had been admitted to hospital with appendicitis between Apr. 1, 1999, and Dec. 31, 2006. The air pollutants studied were ozone, nitrogen dioxide, sulfur dioxide, carbon monoxide, and suspended particulate matter of less than 10 μ and less than 2.5 μ in diameter. We estimated the odds of appendicitis relative to short-term increases in concentrations of selected pollutants, alone and in combination, after controlling for temperature and relative humidity as well as the effects of age, sex and season.

Results

An increase in the interquartile range of the 5-day average of ozone was associated with appendicitis (odds ratio [OR] 1.14, 95% confidence interval [CI] 1.03–1.25). In summer (July–August), the effects were most pronounced for ozone (OR 1.32, 95% CI 1.10–1.57), sulfur dioxide (OR 1.30, 95% CI 1.03–1.63), nitrogen dioxide (OR 1.76, 95% CI 1.20–2.58), carbon monoxide (OR 1.35, 95% CI 1.01–1.80) and particulate matter less than 10 μ in diameter (OR 1.20, 95% CI 1.05–1.38). We observed a significant effect of the air pollutants in the summer months among men but not among women (e.g., OR for increase in the 5-day average of nitrogen dioxide 2.05, 95% CI 1.21–3.47, among men and 1.48, 95% CI 0.85–2.59, among women). The double-pollutant model of exposure to ozone and nitrogen dioxide in the summer months was associated with attenuation of the effects of ozone (OR 1.22, 95% CI 1.01–1.48) and nitrogen dioxide (OR 1.48, 95% CI 0.97–2.24).

Interpretation

Our findings suggest that some cases of appendicitis may be triggered by short-term exposure to air pollution. If these findings are confirmed, measures to improve air quality may help to decrease rates of appendicitis.Appendicitis was introduced into the medical vernacular in 1886.¹ Since then, the prevailing theory of its pathogenesis implicated an obstruction of the appendiceal orifice by a fecalith or lymphoid hyperplasia.² However, this notion does not completely account for variations in incidence observed by age,^3,4 sex,^3,4 ethnic background,^3,4 family history,⁵ temporal–spatial clustering⁶ and seasonality,^3,4 nor does it completely explain the trends in incidence of appendicitis in developed and developing nations.^3,7,8The incidence of appendicitis increased dramatically in industrialized nations in the 19th century and in the early part of the 20th century.¹ Without explanation, it decreased in the middle and latter part of the 20th century.³ The decrease coincided with legislation to improve air quality. For example, after the United States Clean Air Act was passed in 1970,⁹ the incidence of appendicitis decreased by 14.6% from 1970 to 1984.³ Likewise, a 36% drop in incidence was reported in the United Kingdom between 1975 and 1994¹⁰ after legislation was passed in 1956 and 1968 to improve air quality and in the 1970s to control industrial sources of air pollution. Furthermore, appendicitis is less common in developing nations; however, as these countries become more industrialized, the incidence of appendicitis has been increasing.⁷Air pollution is known to be a risk factor for multiple conditions, to exacerbate disease states and to increase all-cause mortality.¹¹ It has a direct effect on pulmonary diseases such as asthma¹¹ and on nonpulmonary diseases including myocardial infarction, stroke and cancer.^11–13 Inflammation induced by exposure to air pollution contributes to some adverse health effects.^14–17 Similar to the effects of air pollution, a proinflammatory response has been associated with appendicitis.^18–20We conducted a case–crossover study involving a population-based cohort of patients admitted to hospital with appendicitis to determine whether short-term increases in concentrations of selected air pollutants were associated with hospital admission because of appendicitis.     

Willingness of patients to change surgeons for a shorter waiting time for joint arthroplasty

Background

To improve access to care, many jurisdictions have proposed waiting-time benchmarks and guarantees. We assessed the willingness of patients to consider changing their surgeon to one with a shorter waiting time for arthroplasty.

Methods

We mailed a questionnaire to 2 random samples of patients who either were awaiting hip or knee replacement arthroplasty or had had one of these procedures within the preceding 3–12 months. We used logistic regression to assess the determinants of patients'' likelihood to consider changing surgeons.

Results

Of 1200 responses from a sample of 2000, 557 (46%) were from patients awaiting surgery and 643 (54%) were from people who had undergone surgery. The mean age of respondents was 69.9 years (standard deviation 10.8), and 682 (57%) were women. The median waiting time for surgery was 8 months. Overall, 753 (63%) of the patients were unlikely to consider changing surgeons. Increased likelihood of changing surgeons was associated with male sex (adjusted odds ratio [OR] 1.49, 95% confidence interval [CI] 1.10–2.02), a high school education or higher (OR 1.73, 95% CI 1.15– 2.62) and having already undergone surgery (OR 1.71, 95% CI 1.19– 2.46). Decreased likelihood was associated with preference for a particular surgeon before referral (OR 0.57, 95% CI 0.42– 0.79), a better score on the EuroQol (EQ-5D) index (a measure of health-related quality of life) (OR 0.39, 95% CI 0.24– 0.66), perception that the waiting time to see the surgeon was acceptable (OR 0.50, 95% CI 0.36–0.70), perception that the waiting time to surgery was acceptable (OR 0.62, 95% CI 0.43–0.91) and perceived fairness of treatment (OR 0.53, 95% CI 0.36– 0.78).

Interpretation

Despite long waits for surgery, most patients, if given the choice, would be unlikely to change their surgeon to one with a shorter waiting time.Long waiting times for elective surgery are a concern in countries with publicly funded health care systems.¹ To try to improve access, governments in Canada and some other countries in the Organisation for Economic Co-operation and Development have proposed or implemented waiting-time benchmarks and care guarantees.² These benchmarks, typically between 3 and 12 months, usually refer to the time between assessment by a specialist and in-patient treatment.³Waiting times for hip and knee arthroplasty are perceived as excessive in many countries, including Canada.^4–6 In 2005, Canada''s federal, provincial and territorial health ministers set a target waiting time of 26 weeks for hip and knee arthroplasty, and in 2007 they agreed to establish waiting-time guarantees by 2010 in selected priority areas, including joint arthroplasty.⁷ A waiting-time guarantee implies that, if necessary medical treatment for a publicly insured service is not available within a medically acceptable timeframe, patients may receive treatment at another facility, even outside their home province, at public expense. This change in the location of treatment implies that another surgeon would perform the surgery. However, patients are not always willing to accept re-referral to a provider with a shorter waiting time.^8–12Most other studies investigating patient choice in the context of long waiting times have referred to the choice of an alternative hospital rather than the choice of an alternative surgeon. Even though many patients may indicate that they are willing to travel to another hospital, fewer actually choose such a change.¹¹ In addition to waiting time,^8,13 other factors influencing provider choice are the hospital''s reputation, follow-up care and travel time.^8,13,14 Little is known about what factors patients consider and what information they want and can use when choosing a provider.^11,15We sought to assess patients'' willingness to consider changing to a surgeon with a shorter waiting time for hip and knee arthroplasty. We formulated the following research questions: Would patients consider changing to a surgeon with shorter waiting times? What factors influence patients'' willingness to consider changing surgeons? Do patients waiting for surgery have a different perspective than patients who have already undergone their surgery?     

Incidence,severity and preventability of medication-related visits to the emergency department: a prospective study

Background

Medication-related visits to the emergency department are an important but poorly understood phenomenon. We sought to evaluate the frequency, severity and preventability of drug-related visits to the emergency department.

Methods

We performed a prospective observational study of randomly selected adults presenting to the emergency department over a 12-week period. Emergency department visits were identified as drug-related on the basis of assessment by a pharmacist research assistant and an emergency physician; discrepancies were adjudicated by 2 independent reviewers.

Results

Among the 1017 patients included in the study, the emergency department visit was identified as drug-related for 122 patients (12.0%, 95% confidence interval [CI] 10.1%–14.2%); of these, 83 visits (68.0%, 95% CI 59.0%–76.2%) were deemed preventable. Severity was classified as mild in 15.6% of the 122 cases, moderate in 74.6% and severe in 9.8%. The most common reasons for drug-related visits were adverse drug reactions (39.3%), nonadherence (27.9%) and use of the wrong or suboptimal drug (11.5%). The probability of admission was significantly higher among patients who had a drug-related visit than among those whose visit was not drug-related (OR 2.18, 95% CI 1.46–3.27, p < 0.001), and among those admitted, the median length of stay was longer (8.0 [interquartile range 23.5] v. 5.5 [interquartile range 10.0] days, p = 0.06).

Interpretation

More than 1 in 9 emergency department visits are due to drug-related adverse events, a potentially preventable problem in our health care system.Adverse drug-related events are unfavourable occurrences related to the use or misuse of medications.¹ It has been estimated that such events account for 17 million emergency department visits and 8.7 million hospital admissions annually in the United States.^2,3 Between 1995 and 2000, costs associated with adverse drug-related events rose from US$76.6 billion to over US$177.4 billion.^3,4Adverse drug-related events have recently been evaluated in ambulatory care settings and among patients admitted to hospital,^5–9 and it has been estimated that 5%–25% of hospital admissions are drug-related.^7,8 Unfortunately, emergency department visits are not reflected in most hospital studies, because patients seen in the emergency department for an adverse drug-related event are typically not admitted.¹⁰ In addition, most research evaluating drug-related visits to the emergency department has involved retrospective studies or analysis of administrative data.^11–13 Retrospective studies may underestimate the incidence of drug-related visits because information may be missing or inaccurately documented.¹⁴ Finally, studies performed to date have used variable definitions of “drug-related events,”^1,10 which limits comparative evaluation and generalizability.Despite the burden of drug-related morbidity and mortality, prospective research characterizing drug-related visits to the emergency department has been limited.^15–17 We sought to overcome some of the limitations of research in this area by using a prospective design and a comprehensive definition of adverse drug-related events. The purpose of this study was to evaluate the frequency, severity and preventability of drug-related visits to the emergency department of a large tertiary care hospital, to classify the visits by type of drug-related problem and to identify patient, prescriber, drug and system factors associated with these visits.