Comparison of black–white disparities in preterm birth between Canada and the United States

Background:

A higher risk of preterm birth among black women than among white women is well established in the United States. We compared differences in preterm birth between non-Hispanic black and white women in Canada and the US, hypothesizing that disparities would be less extreme in Canada given the different historical experiences of black populations and Canada’s universal health care system.

Methods:

Using data on singleton live births in Canada and the US for 2004–2006, we estimated crude and adjusted risk ratios and risk differences in preterm birth (< 37 wk) and very preterm birth (< 32 wk) among non-Hispanic black versus non-Hispanic white women in each country. Adjusted models for the US were standardized to the covariate distribution of the Canadian cohort.

Results:

In Canada, 8.9% and 5.9% of infants born to black and white mothers, respectively, were preterm; the corresponding figures in the US were 12.7% and 8.0%. Crude risk ratios for preterm birth among black women relative to white women were 1.49 (95% confidence interval [CI] 1.32 to 1.66) in Canada and 1.57 (95% CI 1.56 to 1.58) in the US (p value for heterogeneity [p_H] = 0.3). The crude risk differences for preterm birth were 2.94 (95% CI 1.91 to 3.96) in Canada and 4.63 (95% CI 4.56 to 4.70) in the US (p_H = 0.003). Adjusted risk ratios for preterm birth (p_H = 0.1) were slightly higher in Canada than in the US, whereas adjusted risk differences were similar in both countries. Similar patterns were observed for racial disparities in very preterm birth.

Interpretation:

Relative disparities in preterm birth and very preterm birth between non-Hispanic black and white women were similar in magnitude in Canada and the US. Absolute disparities were smaller in Canada, which reflects a lower overall risk of preterm birth in Canada than in the US in both black and white populations.In the United States, a higher risk of preterm birth among black women than among white women is well established.^1–3 This racial disparity is of great concern because preterm birth is a leading cause of perinatal mortality and is predictive of developmental problems and adverse health outcomes later in life.⁴ The underlying causes of the racial disparity in preterm birth in the US are not well understood, although research has suggested contributing roles for a wide range of factors, including socioeconomic disadvantage,⁵ poor neighbourhood conditions (e.g., poverty, crime),^5,6 lack of access to health care,⁷ psychosocial stress,⁸ racial discrimination⁹ and adverse health behaviours.¹⁰Rates of preterm birth have consistently been lower in Canada than in the US.^11,12 However, in contrast to the US, little is known about differences in rates by race or ethnicity in Canada. There is evidence that African-born and Caribbean-born women in the provinces of Quebec and Ontario have higher rates of preterm birth than Canadian-born women.^13–15 Although the magnitude of these differences is smaller than the disparity in preterm births between black and white women in the US,¹⁶ foreign-born black women in the US have been found to be at lower risk of preterm birth than US-born black women.^17,18In both Canada and the US, socioeconomic conditions at both individual and neighbourhood levels are important predictors of preterm birth.^19–21 Although the income gap between black and white people is markedly smaller in Canada than in the US,²² black populations in both countries have lower education levels, higher unemployment rates and a greater likelihood of living in low-quality neighbourhoods compared with white populations.²³ Canada and the US share similar social and economic influences, yet the historical experiences of black populations and the social welfare systems (e.g., universal health care) are quite different in the 2 countries. Black people constitute about 13% of the total US population, but only about 3% of the Canadian population.^24,25 The overwhelming majority of Canada’s black population are immigrants who entered the country after 1960 and their descendants, whereas more than 85% of black Americans can trace their ancestry 3 or more generations in the US, with most being descendants of slaves.²²The objectives of our study are twofold. First, using data from a new cohort linking birth registrations with information from the 2006 Canadian long-form census, we present Canada-wide estimates of differences in preterm birth rates between black and white populations. Second, we use comparable methodology to compare racial differences in preterm birth rates between Canada and the US. Given different historical experiences of black populations in the 2 countries, as well as Canada’s commitment to universal health care and its general perception as a more egalitarian society than the US,²² we hypothesized that we would observe smaller racial disparities in the rates in Canada than in the US.     

Effectiveness of interventions designed to reduce the use of imaging for low-back pain: a systematic review

Background:Rates of imaging for low-back pain are high and are associated with increased health care costs and radiation exposure as well as potentially poorer patient outcomes. We conducted a systematic review to investigate the effectiveness of interventions aimed at reducing the use of imaging for low-back pain.Methods:We searched MEDLINE, Embase, CINAHL and the Cochrane Central Register of Controlled Trials from the earliest records to June 23, 2014. We included randomized controlled trials, controlled clinical trials and interrupted time series studies that assessed interventions designed to reduce the use of imaging in any clinical setting, including primary, emergency and specialist care. Two independent reviewers extracted data and assessed risk of bias. We used raw data on imaging rates to calculate summary statistics. Study heterogeneity prevented meta-analysis.Results:A total of 8500 records were identified through the literature search. Of the 54 potentially eligible studies reviewed in full, 7 were included in our review. Clinical decision support involving a modified referral form in a hospital setting reduced imaging by 36.8% (95% confidence interval [CI] 33.2% to 40.5%). Targeted reminders to primary care physicians of appropriate indications for imaging reduced referrals for imaging by 22.5% (95% CI 8.4% to 36.8%). Interventions that used practitioner audits and feedback, practitioner education or guideline dissemination did not significantly reduce imaging rates. Lack of power within some of the included studies resulted in lack of statistical significance despite potentially clinically important effects.Interpretation:Clinical decision support in a hospital setting and targeted reminders to primary care doctors were effective interventions in reducing the use of imaging for low-back pain. These are potentially low-cost interventions that would substantially decrease medical expenditures associated with the management of low-back pain.Current evidence-based clinical practice guidelines recommend against the routine use of imaging in patients presenting with low-back pain.^1–3 Despite this, imaging rates remain high,^4,5 which indicates poor concordance with these guidelines.^6,7Unnecessary imaging for low-back pain has been associated with poorer patient outcomes, increased radiation exposure and higher health care costs.⁸ No short- or long-term clinical benefits have been shown with routine imaging of the low back, and the diagnostic value of incidental imaging findings remains uncertain.^9–12 A 2008 systematic review found that imaging accounted for 7% of direct costs associated with low-back pain, which in 1998 translated to more than US$6 billion in the United States and £114 million in the United Kingdom.¹³ Current costs are likely to be substantially higher, with an estimated 65% increase in spine-related expenditures between 1997 and 2005.¹⁴Various interventions have been tried for reducing imaging rates among people with low-back pain. These include strategies targeted at the practitioner such as guideline dissemination,^15–17 education workshops,^18,19 audit and feedback of imaging use,^7,20,21 ongoing reminders⁷ and clinical decision support.^22–24 It is unclear which, if any, of these strategies are effective.²⁵ We conducted a systematic review to investigate the effectiveness of interventions designed to reduce imaging rates for the management of low-back pain.     

The Cedar Project: risk factors for transition to injection drug use among young, urban Aboriginal people

Background:

Studies suggest that Aboriginal people in Canada are over-represented among people using injection drugs. The factors associated with transitioning to the use of injection drugs among young Aboriginal people in Canada are not well understood.

Methods:

The Cedar Project is a prospective cohort study (2003–2007) involving young Aboriginal people in Vancouver and Prince George, British Columbia, who use illicit drugs. Participants’ venous blood samples were tested for antibodies to HIV and the hepatitis C virus, and drug use was confirmed using saliva screens. The primary outcomes were use of injection drugs at baseline and tranisition to injection drug use in the six months before each follow-up interview.

Results:

Of 605 participants, 335 (55.4%) reported using injection drugs at baseline. Young people who used injection drugs tended to be older than those who did not, female and in a relationship. Participants who injected drugs were also more likely than those who did not to have been denied shelter because of their drug use, to have been incarcerated, to have a mental illness and to have been involved in sex work. Transition to injection drug use occurred among 39 (14.4%) participants, yielding a crude incidence rate of 19.8% and an incidence density of 11.5 participants per 100 person-years. In unadjusted analysis, transition to injection drug use was associated with being female (odds ratio [OR] 1.98, 95% confidence interval (CI) 1.06–3.72), involved in sex work (OR 3.35, 95% CI 1.75–6.40), having a history of sexually transmitted infection (OR 2.01, 95% CI 1.07–3.78) and using drugs with sex-work clients (OR 2.51, 95% CI 1.19–5.32). In adjusted analysis, transition to injection drug use remained associated with involvement in sex work (adjusted OR 3.94, 95% CI 1.45–10.71).

Interpretation:

The initiation rate for injection drug use of 11.5 participants per 100 person-years among participants in the Cedar Project is distressing. Young Aboriginal women in our study were twice as likely to inject drugs as men, and participants who injected drugs at baseline were more than twice as likely as those who did not to be involved in sex work.Aboriginal leadership in Canada is deeply concerned about substance use, more specifically injection drug use and its association with the spread of HIV and the hepatitis C virus among Aboriginal young people.^1,2 Recent studies in Canada suggest that Aboriginal people are over-represented among people who use injection drugs.^3,4 For Aboriginal young people in Canada under the age of 24 years, injection drug use accounts for the majority of infections with the hepatitis C virus (70%–80%)^5,6 and over half (59%) of HIV infections.⁷Indigenous scholars have stated that research on substance use within Aboriginal communities must consider the context of colonization, including the intergenerational impacts of the residential school and child welfare systems.^8–11 It is now well documented that Aboriginal children experienced extensive psychological, sexual, physical and emotional abuses within those systems.^12,13 As former students of residential schools raise children and grandchildren, the intergenerational effects of abuse and familial fragmentation are evident in communities where interpersonal violence and drug dependence are pervasive.^14–16A priority for preventing infections with HIV and hepatitis C among young Aboriginal people is the development of programs and rights-based,^18,19 youth-informed¹⁷ policies aimed at preventing the use of injection drugs. However, research to date has not provided sufficient evidence to inform such development.^2,19 Concerns over this paucity of information led to the launch of a two-city cohort study in 2003 to address HIV-related vulnerabilities among young Aboriginal people in British Columbia — a unique study centred on at-risk youth and supported by and partnered with Aboriginal investigators and collaborators.We report here baseline and longitudinal data on the factors associated with injection drug use and the transition to injection drug use to inform the development of prevention programs and policies.     

Cost-effectiveness of second-line antihyperglycemic therapy in patients with type 2 diabetes mellitus inadequately controlled on metformin

Background:

Metformin is widely accepted as first-line pharmacotherapy for patients with type 2 diabetes mellitus when glycemic control cannot be achieved by lifestyle interventions alone. However, uncertainty exists regarding the optimal second-line therapy for patients whose diabetes is inadequately controlled by metformin monotherapy. Increased use of newer, more costly agents, along with the rising incidence of type 2 diabetes, carries significant budgetary implications for health care systems. We conducted this analysis to determine the relative costs, benefits and cost-effectiveness of options for second-line treatment of type 2 diabetes.

Methods:

We used the United Kingdom Prospective Diabetes Study Outcomes Model to forecast diabetes-related complications, quality-adjusted life-years and costs of alternative second-line therapies available in Canada for adults with type 2 diabetes inadequately controlled by metformin. We obtained clinical data from a systematic review and mixed treatment comparison meta-analysis, and we obtained information on costs and utilities from published sources. We performed extensive sensitivity analyses to test the robustness of results to variation in inputs and assumptions.

Results:

Sulphonylureas, when added to metformin, were associated with the most favourable cost-effectiveness estimate, with an incremental cost of $12 757 per quality-adjusted life-year gained, relative to continued metformin monotherapy. Treatment with other agents, including thiazolidinediones and dipeptidyl peptidase-4 inhibitors, had unfavourable cost-effectiveness estimates compared with sulphonylureas. These results were robust to extensive sensitivity analyses.

Interpretation:

For most patients with type 2 diabetes that is inadequately controlled with metformin monotherapy, the addition of a sulphonylurea represents the most cost-effective second-line therapy.Type 2 diabetes mellitus is a progressive disease typically treated in a stepwise fashion, beginning with lifestyle modification, followed by the addition of one or more oral antihyperglycemic drugs and, finally, administration of exogenous insulin. Metformin monotherapy is widely recommended as first-line pharmacotherapy,^1,2 given its favourable effects in controlling blood glucose and body weight, low risk of hypoglycemia, low cost and association with mortality benefit.³ Multiple second-line treatment strategies are available for patients in whom glycemic control has become inadequate. These approaches are typically used in addition to continued metformin therapy.^4,5 Numerous second-line agents are available in Canada, including older oral agents, such as sulphonylureas, and more recently introduced agents, such as thiazolidinediones and dipeptidyl peptidase-4 inhibitors.The large number of choices for second-line therapy has increased uncertainty regarding the optimal treatment pathway. Recent clinical practice guidelines, including those produced by the Canadian Diabetes Association¹ and by the American Diabetes Association and the European Association for the Study of Diabetes,² have suggested selecting from among several agents on the basis of their respective advantages and disadvantages. There has been a considerable increase in the use of newer, more costly oral antihyperglycemic agents, which has resulted in substantial increases in associated costs to patients and both public and private drug plans in Canada.⁴ In light of current therapeutic uncertainty, the large proportion of patients requiring second-line therapy over time^3,6 and the increasing prevalence of type 2 diabetes,⁷ the utilization and cost of second-line therapy are likely to continue to grow.Informed decisions regarding optimal prescribing and reimbursement of second-line agents by public and private health care payers requires information about clinical benefits, costs and cost-effectiveness.⁸ As part of a larger initiative to determine optimal prescribing of antihyperglycemic agents, we sought to determine the incremental cost-effectiveness of treatment with alternative second-line agents added to metformin in patients with type 2 diabetes no longer adequately controlled by metformin monotherapy.     

Suicidality among sexual minority and transgender adolescents: a nationally representative population-based study of youth in Canada

Background:Very little research has described risk of suicidal ideation and suicide attempt among transgender youth using high-quality, nationally representative data. We aimed to assess risk of suicidality among transgender and sexual minority adolescents in Canada.Methods:We analyzed a subsample of adolescents aged 15–17 years from the 2019 Canadian Health Survey on Children and Youth, a nationally representative, cross-sectional survey. We defined participants’ transgender identity (self-reported gender different from sex assigned at birth) and sexual minority status (self-reported attraction to people of the same gender) as exposures, and their self-reported previous-year suicidal ideation and lifetime suicide attempt as outcomes.Results:We included 6800 adolescents aged 15–17 years, including 1130 (16.5%) who indicated some degree of same-gender attraction, 265 (4.3%) who were unsure of their attraction and 50 (0.6%) who reported a transgender identity. Compared with cisgender, heterosexual adolescents, transgender adolescents showed 5 times the risk of suicidal ideation (95% confidence interval [CI] 3.63 to 6.75; 58% v. 10%) and 7.6 times the risk of suicide attempt (95% CI 4.76 to 12.10; 40% v. 5%). Among cisgender adolescents, girls attracted to girls had 3.6 times the risk of previous-year suicidal ideation (95% CI 2.59 to 5.08) and 3.3 times the risk of having ever attempted suicide (95% CI 1.81 to 6.06), compared with their heterosexual peers. Adolescents attracted to multiple genders had 2.5 times the risk of suicidal ideation (95% CI 2.12 to 2.98) and 2.8 times the risk of suicide attempt (95% CI 2.18 to 3.68). Youth questioning their sexual orientation had twice the risk of having attempted suicide in their lifetime (95% CI 1.23 to 3.36).Interpretation:We observed that transgender and sexual minority adolescents were at increased risk of suicidal ideation and attempt compared with their cisgender and heterosexual peers. These findings highlight the need for inclusive prevention approaches to address suicidality among Canada’s diverse youth population.

Suicide is the second leading cause of death among adolescents and young adults aged 15–24 years in Canada.^1,2 Suicidal ideation and suicide attempt are common among adolescents³ and are risk factors for death by suicide.⁴ Sexual minority youth (i.e., youth who are attracted to the same gender or multiple genders, or who identify as lesbian, gay, bisexual or queer)⁵ are known to be at increased risk of poor mental health,^6–8 including suicidal ideation and attempt.^5–10 Over the previous 2 decades, stigma around identifying as a sexual minority has reduced;⁷ however, the risk of poor mental health and of suicidality remains high among sexual minority youth.^7,11 This population is still more likely to experience bullying and peer victimization,^9,12,13 which is associated with suicidality among sexual minority adolescents.⁵Transgender youth are those whose gender identity does not match their sex assigned at birth.¹⁴ Among other terms, gender-nonconforming, nonbinary, genderqueer and genderfluid are used to describe the gender identity of a subset of young people who identify outside the gender binary (i.e., as neither male nor female) or who experience fluidity between genders.⁹ Suicidality among transgender and gender-nonconforming adolescents is not as well studied. In a Canadian survey of transgender and gender-nonconforming youth aged 14–25 years, 64% of participants reported that they had seriously considered suicide in the previous 12 months.¹⁵ Transgender and gender-nonconforming youth seem to have a higher probability of many risk factors for suicidality, including peer victimization,^8,16 family dysfunction^7,17 and barriers to accessing mental health care.¹⁸ However, the epidemiology of suicidality among transgender and gender-nonconforming youth remains understudied in population-based samples; most research on the mental health of transgender youth comes from small community samples of help-seeking youth or targeted surveys of transgender adolescents.^5,19,20 Two population-based studies from California²¹ and New Zealand²² suggested that transgender youth are at increased risk of suicidal ideation and suicide attempt. However, only the New Zealand study²² used the gold-standard measure of gender identity, contrasting adolescents’ sex assigned at birth with their self-identified gender.²³Further epidemiological research employing large, representative samples and adequate measures of gender identity is needed to understand the burden of suicidality among lesbian, gay, bisexual, transgender and queer youth. We sought to build on existing evidence to assess risk of suicidal ideation and attempt among transgender and sexual minority adolescents in Canada, as compared with their cisgender and heterosexual peers, as well as to explore the relation between suicidality and experience of bullying.     

The potential economic impact of restricted access to angiotensin-receptor blockers

Background

The use of angiotensin-receptor blockers increased by more than 4000% in Canada from 1996 to 2006. The benefit of these medications over angiotensin-converting-enzyme (ACE) inhibitors has not been proven aside from a reduction in dry cough. We estimated the potential cost savings that might have been achieved had access to angiotensin-receptor blockers been restricted.

Methods

We performed a cost-minimization analysis with a decision-tree model using a societal perspective over a one-year period. Sources of data for model parameters included IMS Health Canada data collected from one-third of all retail pharmacies for the cost and use of angiotensin-receptor blockers and ACE inhibitors in each province, as well as published studies for administrative costs and incidence of dry cough. We used Monte Carlo simulations with 10 000 iterations to test the impact of several model parameters (e.g., drug prices, administrative costs and the incidence of dry cough). All data are in 2006 Canadian dollars.

Results

A policy that would have restricted access to angiotensin-receptor blockers might have saved more than $77 million in Canada in 2006. The simulations yielded similar savings for the year (mean $58.3 million, 95% confidence interval $29.3 million to $90.8 million). Every simulation showed a cost savings.

Interpretation

Had access to angiotensin-receptor blockers been restricted, the potential cost savings to the Canadian health care system might have been more than $77 million in 2006, likely without any adverse effect on cardiovascular health.Costs of cardiovascular drugs in Canada increased by more than 200% from 1996 to 2006. The use of angiotensin-receptor blockers grew at an especially high rate, rising by more than 4000% during that period.¹ Such an increase in the use of these agents is not strongly supported by evidence.¹ Although angiotensin-receptor blockers were effective in reducing mortality and morbidity associated with hypertension in one large trial, patients in the control group were not given an angiotensin-converting-enzyme (ACE) inhibitor.² Instead, they received atenolol, a β-blocker, a drug class whose use is increasingly being questioned in the management of high blood pressure uncomplicated by prior myocardial infarction, heart failure or tachyarrhythmia.^3,4 Although angiotensin-receptor blockers are not associated with dry cough, a side effect reported by 5%–35% of patients taking ACE inhibitors,⁵ this side effect is benign and fully reversible once the drug is stopped. Meta-analyses that included several randomized trials failed to show superiority of angiotensin-receptor blockers over ACE inhibitors for the treatment of hypertension,⁶ heart failure⁷ or the secondary prevention of coronary artery disease.⁸Innovative policies are needed to offset the ever-increasing costs of cardiovascular drugs in Canada. Currently, British Columbia is the only province that restricts access to angiotensin-receptor blockers. Given that these agents can safely be substituted by ACE inhibitors and still yield similar clinical outcomes,^6–8 restricting their access is expected to lead to cost savings without adversely affecting patient heath. We estimated the potential cost savings that might have been achieved had access to angiotensin-receptor blockers been restricted in Canada in 2006.     

Geographic concentration of SARS-CoV-2 cases by social determinants of health in metropolitan areas in Canada: a cross-sectional study

Background:Understanding inequalities in SARS-CoV-2 transmission associated with the social determinants of health could help the development of effective mitigation strategies that are responsive to local transmission dynamics. This study aims to quantify social determinants of geographic concentration of SARS-CoV-2 cases across 16 census metropolitan areas (hereafter, cities) in 4 Canadian provinces, British Columbia, Manitoba, Ontario and Quebec.Methods:We used surveillance data on confirmed SARS-CoV-2 cases and census data for social determinants at the level of the dissemination area (DA). We calculated Gini coefficients to determine the overall geographic heterogeneity of confirmed cases of SARS-CoV-2 in each city, and calculated Gini covariance coefficients to determine each city’s heterogeneity by each social determinant (income, education, housing density and proportions of visible minorities, recent immigrants and essential workers). We visualized heterogeneity using Lorenz (concentration) curves.Results:We observed geographic concentration of SARS-CoV-2 cases in cities, as half of the cumulative cases were concentrated in DAs containing 21%–35% of their population, with the greatest geographic heterogeneity in Ontario cities (Gini coefficients 0.32–0.47), followed by British Columbia (0.23–0.36), Manitoba (0.32) and Quebec (0.28–0.37). Cases were disproportionately concentrated in areas with lower income and educational attainment, and in areas with a higher proportion of visible minorities, recent immigrants, high-density housing and essential workers. Although a consistent feature across cities was concentration by the proportion of visible minorities, the magnitude of concentration by social determinant varied across cities.Interpretation:Geographic concentration of SARS-CoV-2 cases was observed in all of the included cities, but the pattern by social determinants varied. Geographically prioritized allocation of resources and services should be tailored to the local drivers of inequalities in transmission in response to the resurgence of SARS-CoV-2.

The COVID-19 epidemic in Canada has varied in size and trajectory across provinces and large cities.^1,2 At the national level³ and within regions,^4,5 the burden of confirmed SARS-CoV-2 cases and severe COVID-19 outcomes has fallen disproportionately on socially and economically marginalized communities. ⁶ Social determinants of health refer to nonmedical factors influencing health outcomes, and structural determinants encompass cultural norms, policies and institutions that generate social stratification and determine socioeconomic position.^7,8 In Canada and elsewhere, data have consistently highlighted the importance of determinants such as household size and density, work in essential services and structural racism (measured by proxy) in the relative risk of COVID-19.^9–17Understanding the factors associated with geographic patterns of transmission within cities can help identify the populations and, specifically, the contexts with the greatest risks. Geographic analyses can enable better allocation of resources, tailoring of policies and implementation of context-specific strategies to more effectively and efficiently curb local transmission. ¹⁸ Although respiratory virus transmission is often geographically clustered within a city,¹⁹ the early public health response to SARS-CoV-2 transmission in Canada did little to take within-city clustering into account.^20,21 Similarly, few studies have quantified and compared the geographic concentration of SARS-CoV-2 cases by social determinants across Canada, and the extent to which the magnitude of inequalities might vary among cities and provinces.^19,22 We therefore sought to quantify and compare the magnitude of geographic concentration of SARS-CoV-2 cases by area-level social determinants of health across metropolitan areas in British Columbia, Manitoba, Ontario and Quebec, Canada.     

Cost-effectiveness of self-monitoring of blood glucose in patients with type 2 diabetes mellitus managed without insulin

Background

The benefits of self-monitoring blood glucose levels are unclear in patients with type 2 diabetes mellitus who do not use insulin, but there are considerable costs. We sought to determine the cost effectiveness of self-monitoring for patients with type 2 diabetes not using insulin.

Methods

We performed an incremental cost-effectiveness analysis of the self-monitoring of blood glucose in adults with type 2 diabetes not taking insulin. We used the United Kingdom Prospective Diabetes Study (UKPDS) model to forecast diabetes-related complications, corresponding quality-adjusted life years and costs. Clinical data were obtained from a systematic review comparing self-monitoring with no self-monitoring. Costs and utility decrements were derived from published sources. We performed sensitivity analyses to examine the robustness of the results.

Results

Based on a clinically modest reduction in hemoglobin A_1C of 0.25% (95% confidence interval 0.15–0.36) estimated from the systematic review, the UKPDS model predicted that self-monitoring performed 7 or more times per week reduced the lifetime incidence of diabetes-related complications compared with no self-monitoring, albeit at a higher cost (incremental cost per quality-adjusted life year $113 643). The results were largely unchanged in the sensitivity analysis, although the incremental cost per quality-adjusted life year fell within widely cited cost-effectiveness thresholds when testing frequency or the price per test strip was substantially reduced from the current levels.

Interpretation

For most patients with type 2 diabetes not using insulin, use of blood glucose test strips for frequent self-monitoring (≥ 7 times per week) is unlikely to represent efficient use of finite health care resources, although periodic testing (e.g., 1 or 2 times per week) may be cost-effective. Reduced test strip price would likely also improve cost-effectiveness.Self-monitoring of blood glucose in patients with diabetes who use insulin may contribute to improved glycemic control and reduced hypoglycemia by allowing for self-adjustments in insulin dose to be made based on meter readings.¹ Self-monitoring may also allow for appropriate changes in diet and physical activity to be made. However, the benefits of self-monitoring of blood glucose for patients not using insulin are less clear. Hypoglycemia is less frequent in this population² and is confined mainly to those taking secretagogues. The degree to which patients can adjust the dose of oral antidiabetes drugs in response to readings is limited.Nevertheless, self-monitoring of blood glucose is routinely recommended for patients who are not using insulin.¹ This results in major investments in this technology by patients and payers.³ In 2006, $250 million was spent on blood glucose test strips in 8 publicly funded drugs plans in Newfoundland and Labrador, Nova Scotia, Quebec, Ontario, Manitoba, Saskatchewan and British Columbia, while over $120 million was spent in privately funded drug plans in Canada.⁴ In some publicly funded drug plans in Canada, blood glucose test strips are among the top 5 classes in terms of total expenditure,⁵ with costs exceeding those for all oral antidiabetes drugs combined.^4,6 It is estimated that more than 50% of the total expenditure on blood glucose test strips is for patients with type 2 diabetes who are not using insulin.³ Costs related to test strips are expected to rise steadily^5,7 because of the increasing prevalence of type 2 diabetes.⁸Decisions about the prescribing and reimbursement of blood glucose test strips require consideration of information about the costs and clinical benefits.^9,10 As part of a larger initiative to determine the optimal use of this technology, we sought to determine the cost-effectiveness of self-monitoring of blood glucose for patients with type 2 diabetes who do not use insulin, based on data from our systematic review¹¹ of the available clinical evidence.     

Risk of suicide after a concussion

Background:Head injuries have been associated with subsequent suicide among military personnel, but outcomes after a concussion in the community are uncertain. We assessed the long-term risk of suicide after concussions occurring on weekends or weekdays in the community.Methods:We performed a longitudinal cohort analysis of adults with diagnosis of a concussion in Ontario, Canada, from Apr. 1, 1992, to Mar. 31, 2012 (a 20-yr period), excluding severe cases that resulted in hospital admission. The primary outcome was the long-term risk of suicide after a weekend or weekday concussion.Results:We identified 235 110 patients with a concussion. Their mean age was 41 years, 52% were men, and most (86%) lived in an urban location. A total of 667 subsequent suicides occurred over a median follow-up of 9.3 years, equivalent to 31 deaths per 100 000 patients annually or 3 times the population norm. Weekend concussions were associated with a one-third further increased risk of suicide compared with weekday concussions (relative risk 1.36, 95% confidence interval 1.14–1.64). The increased risk applied regardless of patients’ demographic characteristics, was independent of past psychiatric conditions, became accentuated with time and exceeded the risk among military personnel. Half of these patients had visited a physician in the last week of life.Interpretation:Adults with a diagnosis of concussion had an increased long-term risk of suicide, particularly after concussions on weekends. Greater attention to the long-term care of patients after a concussion in the community might save lives because deaths from suicide can be prevented.Suicide is a leading cause of death in both military and community settings.¹ During 2010, 3951 suicide deaths occurred in Canada² and 38 364 in the United States.³ The frequency of attempted suicide is about 25 times higher, and the financial costs in the US equate to about US$40 billion annually.⁴ The losses from suicide in Canada are comparable to those in other countries when adjusted for population size.⁵ Suicide deaths can be devastating to surviving family and friends.⁶ Suicide in the community is almost always related to a psychiatric illness (e.g., depression, substance abuse), whereas suicide in the military is sometimes linked to a concussion from combat injury.^7–10Concussion is the most common brain injury in young adults and is defined as a transient disturbance of mental function caused by acute trauma.¹¹ About 4 million concussion cases occur in the US each year, equivalent to a rate of about 1 per 1000 adults annually;¹² direct Canadian data are not available. The majority lead to self-limited symptoms, and only a small proportion have a protracted course.¹³ However, the frequency of depression after concussion can be high,^14,15 and traumatic brain injury in the military has been associated with subsequent suicide.^8,16 Severe head trauma resulting in admission to hospital has also been associated with an increased risk of suicide, whereas mild concussion in ambulatory adults is an uncertain risk factor.^17–20The aim of this study was to determine whether concussion was associated with an increased long-term risk of suicide and, if so, whether the day of the concussion (weekend v. weekday) could be used to identify patients at further increased risk. The severity and mechanism of injury may differ by day of the week because recreational injuries are more common on weekends and occupational injuries are more common on weekdays.^21–27 The risk of a second concussion, use of protective safeguards, propensity to seek care, subsequent oversight, sense of responsibility and other nuances may also differ for concussions acquired from weekend recreation rather than weekday work.^28–31 Medical care on weekends may also be limited because of shortfalls in staffing.³²     

Incidence and mortality rates of keratinocyte carcinoma from 1998–2017: a population-based study of sex differences in Ontario,Canada

Background:Keratinocyte carcinoma is the most common malignant disease, but it is not captured in major registries. We aimed to describe differences by sex in the incidence and mortality rates of keratinocyte carcinoma in Ontario, Canada.Methods:We conducted a population-based retrospective study of adults residing in Ontario between Jan. 1, 1998, and Dec. 31, 2017, using linked health administrative databases. We identified the first diagnosis of keratinocyte carcinoma using a validated algorithm of health insurance claims, and deaths related to keratinocyte carcinoma from death certificates. We calculated the incidence and mortality rates of keratinocyte carcinoma, stratified by sex, age and income quintile. We evaluated trends using the average annual percentage change (AAPC) based on joinpoint regression.Results:After decreasing from 1998 to 2003, the incidence rate of keratinocyte carcinoma increased by 30% to 369 per 100 000 males and 345 per 100 000 females in 2017 (AAPC 1.9%, 95% confidence interval [CI] 1.7 to 2.1 from 2003 to 2017). The incidence rate was higher in females younger than 55 years, but higher in males aged 55 years or older. Between 2008 and 2017, the incidence rate rose faster in females than males aged 45–54 years (AAPC 1.2% v. 0.5%, p = 0.01) and 55–64 years (1.2% v. 0.1%, p < 0.01). The incidence was higher in males than females in the higher income quintiles. Between 1998 and 2017, the mortality rate of keratinocyte carcinoma was 1.8 times higher in males than females, on average, and rose 4.8-fold overall (AAPC 8.9%, 95% CI 6.4 to 11.4 in males; 8.0%, 95% CI 5.3–10.8 in females).Interpretation:The population burden of keratinocyte carcinoma is growing, and the incidence and mortality rates rose disproportionately among certain sex- and age-specific groups. This warrants further investigation into causal factors and renewed preventive public health measures.

Keratinocyte carcinoma comprises basal and squamous cell carcinomas, and is the most common malignant disease in Canada and the United States.^1–5 Although keratinocyte carcinoma has a low mortality rate, it is associated with substantial morbidity and impaired quality of life.^2,6,7 Among cancers, it also ranks fifth in health care costs in the US.⁸Epidemiological studies of keratinocyte carcinoma in North America are limited by its exclusion from most cancer registries. ⁹ Previous studies found that higher overall incidence of keratinocyte carcinoma is associated with male sex,^10–14 older age^15–17 and higher socioeconomic status.^18–21 However, differences in the incidence and mortality rates of keratinocyte carcinoma by sex in relation to age and socioeconomic status have not been well characterized.A better understanding of the epidemiology of keratinocyte carcinoma in Canada and differences by sex would inform public health initiatives, health services policy and patient education strategies. This is particularly relevant now, given the recent regulatory approval of systemic immunotherapies for locally advanced or metastatic squamous and basal cell carcinoma.^22–25 Our objective was to identify the population-based incidence and mortality trends of keratinocyte carcinoma in Ontario, Canada over 2 decades and to evaluate sex differences.     

Diversity among health care leaders in Canada: a cross-sectional study of perceived gender and race

Background:Diverse health care leadership teams may improve health care experiences and outcomes for patients. We sought to explore the race and gender of hospital and health ministry executives in Canada and compare their diversity with that of the populations they serve.Methods:This cross-sectional study included leaders of Canada’s largest hospitals and all provincial and territorial health ministries. We included individuals listed on institutional websites as part of the leadership team if a name and photo were available. Six reviewers coded and analyzed the perceived race and gender of leaders, in duplicate. We compared the proportion of racialized health care leaders with the race demographics of the general population from the 2016 Canadian Census.Results:We included 3056 leaders from 135 institutions, with reviewer concordance on gender for 3022 leaders and on race for 2946 leaders. Reviewers perceived 37 (47.4%) of 78 health ministry leaders as women, and fewer than 5 (< 7%) of 80 as racialized. In Alberta, Saskatchewan, Prince Edward Island and Nova Scotia, provinces with a centralized hospital executive team, reviewers coded 36 (50.0%) of 72 leaders as women and 5 (7.1%) of 70 as racialized. In British Columbia, New Brunswick and Newfoundland and Labrador, provinces with hospital leadership by region, reviewers perceived 120 (56.1%) of 214 leaders as women and 24 (11.5%) of 209 as racialized. In Manitoba, Ontario and Quebec, where leadership teams exist at each hospital, reviewers perceived 1326 (49.9%) of 2658 leaders as women and 243 (9.2%) of 2633 as racialized. We calculated the representation gap between racialized executives and the racialized population as 14.5% for British Columbia, 27.5% for Manitoba, 20.7% for Ontario, 12.4% for Quebec, 7.6% for New Brunswick, 7.3% for Prince Edward Island and 11.6% for Newfoundland and Labrador.Interpretation:In a study of more than 3000 health care leaders in Canada, gender parity was present, but racialized executives were substantially under-represented. This work should prompt health care institutions to increase racial diversity in leadership.

Race and gender-based disparities in health care leadership^1–4 may negatively affect the health of marginalized patients.^5,6 Diverse leadership is an integral step in establishing equitable health care institutions that serve the needs of all community members.⁷ Many barriers prevent racialized people, women and gender nonbinary individuals from attaining leadership positions, including reduced access to networking opportunities, ^8–10 discrimination from patients and colleagues^2,11–13 and an institutional culture that views white, male leaders as most effective. ^14,15 The intersectional effects of discrimination may intensify these barriers for racialized women and nonbinary people.^16,17 Fundamentally, diversity and inclusion in our institutions is important on the basis of basic human rights for all people.¹⁸Health care leadership in Europe and the United States is thought to lack gender and racial diversity.^19–22 The degree to which these imbalances exist across Canadian health care institutions is not clear. Despite past evidence that men hold a disproportionate number of health care leadership positions in Canada,^23,24 a recent study noted gender parity among leaders of provincial and territorial ministries of health.²⁵ Among university faculty^26,27 and administration, ²⁸ racialized individuals appear to be under-represented, suggesting that a similar trend may exist in health care leadership.Race and gender can be studied in many ways.²⁹ Perceived race is a measure of “the race that others believe you to be,” and these assessments “influence how people are treated and form the basis of racial discrimination including nondeliberate actions that nonetheless lead to socioeconomic inequities.”²⁹ Similarly, perceived gender refers to an observer’s assumptions about a person’s gender, which can lead to differential and unfair treatment. ³⁰ Assessing perceived race and gender provides crucial insights into the ways in which social inequalities are informed and produced.²⁹ In this study, we sought to identify the perceived race and gender of hospital executive leaders in Canada and of nonelected leaders of the provincial and territorial health ministries. Furthermore, we wanted to analyze how the perceived racial composition of health care leadership compares with the racial composition of the population in the geographic areas that these leaders serve.     

Smoking of crack cocaine as a risk factor for HIV infection among people who use injection drugs

Background

Little is known about the possible role that smoking crack cocaine has on the incidence of HIV infection. Given the increasing use of crack cocaine, we sought to examine whether use of this illicit drug has become a risk factor for HIV infection.

Methods

We included data from people participating in the Vancouver Injection Drug Users Study who reported injecting illicit drugs at least once in the month before enrolment, lived in the greater Vancouver area, were HIV-negative at enrolment and completed at least 1 follow-up study visit. To determine whether the risk of HIV seroconversion among daily smokers of crack cocaine changed over time, we used Cox proportional hazards regression and divided the study into 3 periods: May 1, 1996–Nov. 30, 1999 (period 1), Dec. 1, 1999–Nov. 30, 2002 (period 2), and Dec. 1, 2002–Dec. 30, 2005 (period 3).

Results

Overall, 1048 eligible injection drug users were included in our study. Of these, 137 acquired HIV infection during follow-up. The mean proportion of participants who reported daily smoking of crack cocaine increased from 11.6% in period 1 to 39.7% in period 3. After adjusting for potential confounders, we found that the risk of HIV seroconversion among participants who were daily smokers of crack cocaine increased over time (period 1: hazard ratio [HR] 1.03, 95% confidence interval [CI] 0.57–1.85; period 2: HR 1.68, 95% CI 1.01–2.80; and period 3: HR 2.74, 95% CI 1.06–7.11).

Interpretation

Smoking of crack cocaine was found to be an independent risk factor for HIV seroconversion among people who were injection drug users. This finding points to the urgent need for evidence-based public health initiatives targeted at people who smoke crack cocaine.People who inject illegal drugs are known to be at heightened risk of HIV infection and other blood-borne diseases. In 2007, more than 20% of all new cases of HIV infection recorded in Canada were attributed to injection drug use.¹ Behaviours associated with the use of particular injection drugs (e.g., cocaine and heroin) have been identified as key factors driving HIV transmission among drug users in various settings.² However, over the last decade, significant changes in the popularity of specific illegal drugs have been observed.^3,4 In recent years, cities across Canada have experienced an explosive increase in the use of crack cocaine, whereas some drugs, including heroin, appear to be less commonly used.^5–7 The proportion of drug users who smoke crack cocaine and are homeless or have marginal housing has recently been reported to be as high as 86.6% in Vancouver, 66.7% in Edmonton and 62.4% in Toronto.⁸In the United States, a seminal cross-sectional study involving inner-city young adults showed that smoking of crack cocaine was associated with HIV infection.⁹ However, in Canada, despite the documentation of changing patterns of drug use in many communities,⁸ little is known about the impact that increased smoking of crack cocaine has had on the HIV epidemic. This is problematic because public health programs for people who smoke crack cocaine have been highly controversial in Canada.⁶ We conducted a longitudinal study to evaluate whether smoking of crack cocaine has emerged as a risk factor for HIV infection among people who inject drugs.     

Effect of nasal balloon autoinflation in children with otitis media with effusion in primary care: an open randomized controlled trial

Background:Otitis media with effusion is a common problem that lacks an evidence-based nonsurgical treatment option. We assessed the clinical effectiveness of treatment with a nasal balloon device in a primary care setting.Methods:We conducted an open, pragmatic randomized controlled trial set in 43 family practices in the United Kingdom. Children aged 4–11 years with a recent history of ear symptoms and otitis media with effusion in 1 or both ears, confirmed by tympanometry, were allocated to receive either autoinflation 3 times daily for 1–3 months plus usual care or usual care alone. Clearance of middle-ear fluid at 1 and 3 months was assessed by experts masked to allocation.Results:Of 320 children enrolled, those receiving autoinflation were more likely than controls to have normal tympanograms at 1 month (47.3% [62/131] v. 35.6% [47/132]; adjusted relative risk [RR] 1.36, 95% confidence interval [CI] 0.99 to 1.88) and at 3 months (49.6% [62/125] v. 38.3% [46/120]; adjusted RR 1.37, 95% CI 1.03 to 1.83; number needed to treat = 9). Autoinflation produced greater improvements in ear-related quality of life (adjusted between-group difference in change from baseline in OMQ-14 [an ear-related measure of quality of life] score −0.42, 95% CI −0.63 to −0.22). Compliance was 89% at 1 month and 80% at 3 months. Adverse events were mild, infrequent and comparable between groups.Interpretation:Autoinflation in children aged 4–11 years with otitis media with effusion is feasible in primary care and effective both in clearing effusions and improving symptoms and ear-related child and parent quality of life. Trial registration: ISRCTN, No. 55208702.Otitis media with effusion, also known as glue ear, is an accumulation of fluid in the middle ear, without symptoms or signs of an acute ear infection. It is often associated with viral infection.^1–3 The prevalence rises to 46% in children aged 4–5 years,⁴ when hearing difficulty, other ear-related symptoms and broader developmental concerns often bring the condition to medical attention.^3,5,6 Middle-ear fluid is associated with conductive hearing losses of about 15–45 dB HL.⁷ Resolution is clinically unpredictable,^8–10 with about a third of cases showing recurrence.¹¹ In the United Kingdom, about 200 000 children with the condition are seen annually in primary care.^12,13 Research suggests some children seen in primary care are as badly affected as those seen in hospital.^7,9,14,15 In the United States, there were 2.2 million diagnosed episodes in 2004, costing an estimated $4.0 billion.¹⁶ Rates of ventilation tube surgery show variability between countries,^17–19 with a declining trend in the UK.²⁰Initial clinical management consists of reasonable temporizing or delay before considering surgery.¹³ Unfortunately, all available medical treatments for otitis media with effusion such as antibiotics, antihistamines, decongestants and intranasal steroids are ineffective and have unwanted effects, and therefore cannot be recommended.^21–23 Not only are antibiotics ineffective, but resistance to them poses a major threat to public health.^24,25 Although surgery is effective for a carefully selected minority,^13,26,27 a simple low-cost, nonsurgical treatment option could benefit a much larger group of symptomatic children, with the purpose of addressing legitimate clinical concerns without incurring excessive delays.Autoinflation using a nasal balloon device is a low-cost intervention with the potential to be used more widely in primary care, but current evidence of its effectiveness is limited to several small hospital-based trials²⁸ that found a higher rate of tympanometric resolution of ear fluid at 1 month.^29–31 Evidence of feasibility and effectiveness of autoinflation to inform wider clinical use is lacking.^13,28 Thus we report here the findings of a large pragmatic trial of the clinical effectiveness of nasal balloon autoinflation in a spectrum of children with clinically confirmed otitis media with effusion identified from primary care.