Resting heart rate and all-cause and cardiovascular mortality in the general population: a meta-analysis

Background:

Data on resting heart rate and risk of all-cause and cardiovascular mortality are inconsistent; the magnitude of associations between resting heart rate and risk of all-cause and cardiovascular mortality varies across studies. We performed a meta-analysis of prospective cohort studies to quantitatively evaluate the associations in the general population.

Methods:

We searched PubMed, Embase and MEDLINE from inception to Jan. 1, 2015. We used a random-effects model to combine study-specific relative risks and 95% confidence intervals (CIs). We used restricted cubic spline functions to assess the dose–response relation.

Results:

A total of 46 studies were included in the meta-analysis, involving 1 246 203 patients and 78 349 deaths for all-cause mortality, and 848 320 patients and 25 800 deaths for cardiovascular mortality. The relative risk with 10 beats/min increment of resting heart rate was 1.09 (95% CI 1.07–1.12) for all-cause mortality and 1.08 (95% CI 1.06–1.10) for cardiovascular mortality. Compared with the lowest category, patients with a resting heart rate of 60–80 beats/min had a relative risk of 1.12 (95% CI 1.07–1.17) for all-cause mortality and 1.08 (95% CI 0.99–1.17) for cardiovascular mortality, and those with a resting heart rate of greater than 80 beats/min had a relative risk of 1.45 (95% CI 1.34–1.57) for all-cause mortality and 1.33 (95% CI 1.19–1.47) for cardiovascular mortality. Overall, the results did not differ after adjustment for traditional risk factors for cardiovascular disease. Compared with 45 beats/min, the risk of all-cause mortality increased significantly with increasing resting heart rate in a linear relation, but a significantly increased risk of cardiovascular mortality was observed at 90 beats/min. Substantial heterogeneity and publication bias were detected.

Interpretation:

Higher resting heart rate was independently associated with increased risks of all-cause and cardiovascular mortality. This indicates that resting heart rate is a predictor of all-cause and cardiovascular mortality in the general population.Resting heart rate is a familiar, straightforward and inexpensive-to-measure clinical variable, and it can be modified by a number of factors, such as physical activity, psychologic stress, smoking, intake of omega-3 fatty acids and medications.^1–4 Higher heart rate has been linked to increased risks of cardiovascular disease and premature mortality through a multitude of actions, including its detrimental effects on progression of coronary atherosclerosis, on occurrence of myocardial ischemia and ventricular arrhythmia, on left ventricular function and on circulating levels of inflammatory markers.^5–7 However, measurement of resting heart rate has not been recommended in American and European guidelines on risk assessment of cardiovascular disease.^8,9 The major reasons for this may be that the magnitude of risk with each increment of higher resting heart rate has been inconsistent among studies, and that resting heart rate may not be an independent predictor because higher heart rate coexists with traditional risk factors of cardiovascular disease.^10–13 In addition, data are lacking on the dose–response relation between resting heart rate and all-cause and cardiovascular mortality,^5,9 although a previous review showed a continuous increase in risk with resting heart rate above 60 beats/min.⁵Therefore, we conducted a meta-analysis of prospective cohort studies involving the general population, following the MOOSE checklist,¹⁴ to assess the risk of all-cause and cardiovascular mortality associated with each increment of 10 beats/min; to evaluate the possible dose–response relation by restricted cubic spline functions and by pooling risks of all-cause and cardiovascular mortality for comparable categories of resting heart rate (60–80 beats/min and > 80 beats/min); and to evaluate the effect of traditional risk factors of cardiovascular disease on the association of resting heart rate with risk of all-cause and cardiovascular mortality.     

Determinants of variations in initial treatment strategies for stable ischemic heart disease

Background:

The ratio of revascularization to medical therapy (referred to herein as the revascularization ratio) for the initial treatment of stable ischemic heart disease varies considerably across hospitals. We conducted a comprehensive study to identify patient, physician and hospital factors associated with variations in the revascularization ratio across 18 cardiac centres in the province of Ontario. We also explored whether clinical outcomes differed between hospitals with high, medium and low ratios.

Methods:

We identified all patients in Ontario who had stable ischemic heart disease documented by index angiography performed between Oct. 1, 2008, and Sept. 30, 2011, at any of the 18 cardiac centres in the province. We classified patients by initial treatment strategy (medical therapy or revascularization). Hospitals were classified into equal tertiles based on their revascularization ratio. The primary outcome was all-cause mortality. Patient follow-up was until Dec. 31, 2012. Hierarchical logistic regression models identified predictors of revascularization. Multivariable Cox proportional hazards models, with a time-varying covariate for actual treatment received, were used to evaluate the impact of the revascularization ratio on clinical outcomes.

Results:

Variation in revascularization ratios was twofold across the hospitals. Patient factors accounted for 67.4% of the variation in revascularization ratios. Physician and hospital factors were not significantly associated with the variation. Significant patient-level predictors of revascularization were history of smoking, multivessel disease, high-risk findings on noninvasive stress testing and more severe symptoms of angina (v. no symptoms). Treatment at hospitals with a high revascularization ratio was associated with increased mortality compared with treatment at hospitals with a low ratio (hazard ratio 1.12, 95% confidence interval 1.03–1.21).

Interpretation:

Most of the variation in revascularization ratios across hospitals was warranted, in that it was driven by patient factors. Nonetheless, the variation was associated with potentially important differences in mortality.Stable ischemic heart disease is a common manifestation of cardiovascular disease, the leading cause of death in the world.^1,2 The treatment strategies for stable ischemic heart disease include medical therapy alone or in combination with revascularization by percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG).A tremendous amount of research has examined the best initial treatment strategy for stable ischemic heart disease.^3–5 Randomized controlled trials have not shown a difference in major adverse events between optimal medical therapy and revascularization.⁶ Some argue that revascularization should be reserved only for symptom relief.^5,7,8 Criteria for the appropriate use of revascularization have been developed to aid in clinical decision-making; however, a substantial proportion of revascularization procedures for stable ischemic heart disease are performed under clinical circumstances deemed as “uncertain.”^9,10 Reflecting this uncertainty, there is wide regional variation in the rate of coronary revascularization,^11–13 which suggests different thresholds for invasive therapy for stable ischemic heart disease.Studies have predominantly examined the determinants of variations in the type of revascularization modality used.^13,14 There is a paucity of data exploring the determinants of variations in the earlier decision to treat with medical therapy alone or with revascularization. A study published nearly a decade ago did not examine outcomes.⁷ Accordingly, our primary research objective was to determine whether the variations in initial treatment strategies for stable ischemic heart disease are warranted. We conducted a comprehensive population-based study to identify patient, physician and hospital factors associated with variations in treatment strategies within 90 days after angiography. We also explored whether clinical outcomes differed between hospitals with high, medium and low ratios of revascularization to medical therapy (hereafter referred to as the revascularization ratio).     

A comparison of the stages at which cancer is diagnosed in physicians and in the general population in Taiwan

Background:Previous investigations have reported that physicians tend to neglect their own health care; however, they may also use their professional knowledge and networks to engage in healthier lifestyles or seek prompt health services. We sought to determine whether the stage at which cancer is diagnosed differs between physicians and nonphysicians.Methods:We conducted a nationwide matched cohort study over a period of 14 years in Taiwan. We accessed data from two national databases: the National Health Insurance Research Database and the Taiwan Cancer Registry File. We collected data on all patients with the 6 most common cancers in Taiwan (hepatoma, lung, colorectal, oral, female breast and cervical cancer) from 1999 to 2012. We excluded patients less than 25 years of age, as well as those with a history of organ transplantation, cancer or AIDS. We used propensity score matching for age, sex, residence and income to select members for the control (nonphysicians) and experimental (physicians) groups at a 5:1 ratio. We used χ² tests to analyze the distribution of incident cancer stages among physicians and nonphysicians. We compared these associations using multinomial logistic regression. We performed sensitivity analyses for subgroups of doctors and cancers.Results:We identified 274 003 patients with cancer, 542 of whom were physicians. After propensity score matching, we assigned 536 physicians to the experimental group and 2680 nonphysicians to the control group. We found no significant differences in cancer stage distributions between physicians and controls. Multinomial logistic regression and sensitivity analyses showed similar cancer stages in most scenarios; however, physicians had 2.64-fold higher risk of having stage IV cancer at diagnosis in cases of female breast and cervical cancer.Interpretation:In this cohort of physicians in Taiwan, cancer was not diagnosed at earlier stages than in nonphysicians, with the exception of stage IV cancer of the cervix and female breast.The health of physicians is vital to health care systems. Physicians who are unwell mentally or physically are prone to providing suboptimal patient care.¹ Several studies have investigated the risk of cancer for doctors with inconclusive findings;^1–4 few investigations have addressed whether cancer is diagnosed at earlier stages in physicians.Previous investigations have reported that physicians tend to neglect their own physical examinations and, once sick, procrastinate seeking medical treatment.^5–8 However, doctors may use their own professional knowledge and network to engage in healthy lifestyles or seek prompt health services in ways that reduce their risk of illness.^9–11Factors protecting people from advanced cancer stages include attending screening services^12–14 and access to physicians.^15,16 Delayed cancer diagnoses lead to poorer outcomes. We sought to compare the incident cancer stages of the 6 most common cancers between physicians and nonphysicians in Taiwan to determine whether physicians’ cancers were diagnosed at earlier or later stages than nonphysicians’ cancers.     

Incidence of psychotic disorders among first-generation immigrants and refugees in Ontario

Background:

Evidence suggests that migrant groups have an increased risk of psychotic disorders and that the level of risk varies by country of origin and host country. Canadian evidence is lacking on the incidence of psychotic disorders among migrants. We sought to examine the incidence of schizophrenia and schizoaffective disorders in first-generation immigrants and refugees in the province of Ontario, relative to the general population.

Methods:

We constructed a retrospective cohort that included people aged 14–40 years residing in Ontario as of Apr. 1, 1999. Population-based administrative data from physician billings and hospital admissions were linked to data from Citizenship and Immigration Canada. We used Poisson regression models to calculate age- and sex-adjusted incidence rate ratios (IRRs) and 95% confidence intervals (CIs) for immigrant and refugee groups over a 10-year period.

Results:

In our cohort (n = 4 284 694), we found higher rates of psychotic disorders among immigrants from the Caribbean and Bermuda (IRR 1.60, 95% CI 1.29–1.98). Lower rates were found among immigrants from northern Europe (IRR 0.50, 95% CI 0.28–0.91), southern Europe (IRR 0.60, 95% CI 0.41–0.90) and East Asia (IRR 0.56, 95% CI 0.41–0.78). Refugee status was an independent predictor of risk among all migrants (IRR 1.27, 95% CI 1.04–1.56), and higher rates were found specifically for refugees from East Africa (IRR 1.95, 95% CI 1.44–2.65) and South Asia (IRR 1.51, 95% CI 1.08–2.12).

Interpretation:

The differential pattern of risk across ethnic subgroups in Ontario suggests that psychosocial and cultural factors associated with migration may contribute to the risk of psychotic disorders. Some groups may be more at risk, whereas others are protected.Meta-analytic reviews suggest that international migrants have a two- to threefold increased risk of psychosis compared with the host population, and the level of risk varies by country of origin and host country.^1,2 This increased risk may persist into the second and third generations.^2,3 Incidence rates are not typically found to be elevated in the country of origin;^4–7 therefore, it is believed that the migratory or postmigration experience may play a role in the etiology.The migration-related emergence of psychotic disorders is a potential concern in Canada, which receives about 250 000 new immigrants and refugees each year.⁸ However, there is a notable lack of current epidemiological information on the incidence of psychosis among these groups.⁹ Hospital admission data from the early 1900s suggest that European migrants to British Columbia had a higher incidence of schizophrenia than the general population,¹⁰ and more recent data from Ontario suggest higher rates of hospital admission for psychotic disorders in areas with a large proportion of first-generation migrants.¹¹ The fact that a large and increasing proportion of Canada’s population are migrants has been cited as a potential explanation for the higher prevalence of schizophrenia compared with international estimates.¹²The province of Ontario is home to the largest number of migrants in Canada, with first-generation migrants constituting nearly 30% of the population. Canada operates on a human capital model of immigration, using a points-based system that favours younger age, higher education, and proficiency in English or French. Nearly 60% of all newcomers to Canada are economic migrants, 27% are sponsored by a relative living in Canada, and 13% are refugees or temporary workers.⁸ Canada also requires a prearrival medical examination, but less than 0.001% of all applications are denied on the basis of medical grounds, and exemptions may be granted for refugees and some family-reunification applicants.¹³The Canadian migration process differs from that of many countries where the association between migration and psychotic disorders has been previously investigated.^1,2 In most of these countries, migrants generally originate from a smaller number of countries that have historic ties to the host country, and there tends to be a low proportion of refugees, although these processes have changed in recent years. In Canada, migrants come from a wide array of countries, admission policies focus on migrants with professional skills and there is a larger proportion of refugees. Few studies to date have examined the role of refugee status in the risk of psychotic disorders¹⁴ or have assessed all of the migrant groups within a country, because most studies focus on particular groups considered to be at high risk.¹ An examination of migrants to Canada offers a unique opportunity to investigate the risk of psychotic disorders in a group with diverse geographical origins, and the larger proportion of refugees also allows us to investigate their risk separately from immigrant groups. Thus, the breadth, scope and scale of migration to Canada over time offers a diverse and deep population for advancing our understanding of why some groups may have a higher risk of psychotic disorders.Our primary objective was to examine the incidence of schizophrenia and schizoaffective disorders over a 10-year period in first-generation immigrants and refugees in Ontario, relative to the general population. We also compared the incidence among specific migrant groups, stratified by country of birth and refugee status, because research suggests differences in the degree and direction of risk.^1,2 We restricted the sample to first-generation migrants to estimate the extent to which sociodemographic factors had an impact on the risk of schizophrenia and schizoaffective disorders among all migrants.     

Prospective validation of a 1-hour algorithm to rule-out and rule-in acute myocardial infarction using a high-sensitivity cardiac troponin T assay

Background:We aimed to prospectively validate a novel 1-hour algorithm using high-sensitivity cardiac troponin T measurement for early rule-out and rule-in of acute myocardial infarction (MI).Methods:In a multicentre study, we enrolled 1320 patients presenting to the emergency department with suspected acute MI. The high-sensitivity cardiac troponin T 1-hour algorithm, incorporating baseline values as well as absolute changes within the first hour, was validated against the final diagnosis. The final diagnosis was then adjudicated by 2 independent cardiologists using all available information, including coronary angiography, echocardiography, follow-up data and serial measurements of high-sensitivity cardiac troponin T levels.Results:Acute MI was the final diagnosis in 17.3% of patients. With application of the high-sensitivity cardiac troponin T 1-hour algorithm, 786 (59.5%) patients were classified as “rule-out,” 216 (16.4%) were classified as “rule-in” and 318 (24.1%) were classified to the “observational zone.” The sensitivity and the negative predictive value for acute MI in the rule-out zone were 99.6% (95% confidence interval [CI] 97.6%–99.9%) and 99.9% (95% CI 99.3%–100%), respectively. The specificity and the positive predictive value for acute MI in the rule-in zone were 95.7% (95% CI 94.3%–96.8%) and 78.2% (95% CI 72.1%–83.6%), respectively. The 1-hour algorithm provided higher negative and positive predictive values than the standard interpretation of highsensitivity cardiac troponin T using a single cut-off level (both p < 0.05). Cumulative 30-day mortality was 0.0%, 1.6% and 1.9% in patients classified in the rule-out, observational and rule-in groups, respectively (p = 0.001).Interpretation:This rapid strategy incorporating high-sensitivity cardiac troponin T baseline values and absolute changes within the first hour substantially accelerated the management of suspected acute MI by allowing safe rule-out as well as accurate rule-in of acute MI in 3 out of 4 patients. Trial registration: ClinicalTrials.gov, {"type":"clinical-trial","attrs":{"text":"NCT00470587","term_id":"NCT00470587"}}NCT00470587Acute myocardial infarction (MI) is a major cause of death and disability worldwide. As highly effective treatments are available, early and accurate detection of acute MI is crucial.^1–5 Clinical assessment, 12-lead electrocardiography (ECG) and measurement of cardiac troponin levels form the pillars for the early diagnosis of acute MI in the emergency department. Major advances have recently been achieved by the development of more sensitive cardiac troponin assays.^6–15 High-sensitivity cardiac troponin assays, which allow measurement of even low concentrations of cardiac troponin with high precision, have been shown to largely overcome the sensitivity deficit of conventional cardiac troponin assays within the first hours of presentation in the diagnosis of acute MI.^6–15 These studies have consistently shown that the classic diagnostic interpretation of cardiac troponin as a dichotomous variable (troponin-negative and troponin-positive) no longer seems appropriate, because the positive predictive value for acute MI of being troponin-positive was only about 50%.^6–15 The best way to interpret and clinically use high-sensitivity cardiac troponin levels in the early diagnosis of acute MI is still debated.^3,5,7In a pilot study, a novel high-sensitivity cardiac troponin T 1-hour algorithm was shown to allow accurate rule-out and rule-in of acute MI within 1 hour in up to 75% of patients.¹¹ This algorithm is based on 2 concepts. First, high-sensitivity cardiac troponin T is interpreted as a quantitative variable where the proportion of patients who have acute MI increases with increasing concentrations of cardiac troponin T.^6–15 Second, early absolute changes in the concentrations within 1 hour provide incremental diagnostic information when added to baseline levels, with the combination acting as a reliable surrogate for late concentrations at 3 or 6 hours.^6–15 However, many experts remained skeptical regarding the safety of the high-sensitivity cardiac troponin T 1-hour algorithm and its wider applicability.¹⁶ Accordingly, this novel diagnostic concept has not been adopted clinically to date. Because the clinical application of this algorithm would represent a profound change in clinical practice, prospective validation in a large cohort is mandatory before it can be considered for routine clinical use. The aim of this multicentre study was to prospectively validate the high-sensitivity cardiac troponin T 1-hour algorithm in a large independent cohort.     

Preoperative testing before low-risk surgical procedures

Background:There is concern about increasing utilization of low-value health care services, including preoperative testing for low-risk surgical procedures. We investigated temporal trends, explanatory factors, and institutional and regional variation in the utilization of testing before low-risk procedures.Methods:For this retrospective cohort study, we accessed linked population-based administrative databases from Ontario, Canada. A cohort of 1 546 223 patients 18 years or older underwent a total of 2 224 070 low-risk procedures, including endoscopy and ophthalmologic surgery, from Apr. 1, 2008, to Mar. 31, 2013, at 137 institutions in 14 health regions. We used hierarchical logistic regression models to assess patient- and institution-level factors associated with electrocardiography (ECG), transthoracic echocardiography, cardiac stress test or chest radiography within 60 days before the procedure.Results:Endoscopy, ophthalmologic surgery and other low-risk procedures accounted for 40.1%, 34.2% and 25.7% of procedures, respectively. ECG and chest radiography were conducted before 31.0% (95% confidence interval [CI] 30.9%–31.1%) and 10.8% (95% CI 10.8%–10.8%) of procedures, respectively, whereas the rates of preoperative echocardiography and stress testing were 2.9% (95% CI 2.9%–2.9%) and 2.1% (95% CI 2.1%–2.1%), respectively. Significant variation was present across institutions, with the frequency of preoperative ECG ranging from 3.4% to 88.8%. Receipt of preoperative ECG and radiography were associated with older age (among patients 66–75 years of age, for ECG, adjusted odds ratio [OR] 18.3, 95% CI 17.6–19.0; for radiography, adjusted OR 2.9, 95% CI 2.8–3.0), preoperative anesthesia consultation (for ECG, adjusted OR 8.7, 95% CI 8.5–8.8; for radiography, adjusted OR 2.2, 95% CI 2.1–2.2) and preoperative medical consultation (for ECG, adjusted OR 6.8, 95% CI 6.7–6.9; for radiography, adjusted OR 3.6, 95% CI 3.5–3.6). The median ORs for receipt of preoperative ECG and radiography were 2.3 and 1.6, respectively.Interpretation:Despite guideline recommendations to limit testing before low-risk surgical procedures, preoperative ECG and chest radiography were performed frequently. Significant variation across institutions remained after adjustment for patient- and institution-level factors.In response to concerns about increasing utilization of low-value health care services, the American Board of Internal Medicine Foundation launched the Choosing Wisely campaign in the United States in 2012.¹ The goal of the campaign is to encourage conversations between physicians and patients about low-value care by defining “top 5” lists of tests, treatments and procedures that may be unnecessary or unsupported by evidence.¹ Subsequent Choosing Wisely campaigns have followed in other countries, including Canada starting in April 2014.^2,3 Of interest for health policy-makers, payers and clinicians are current utilization rates for the procedures mentioned in these recommendations. Establishing baseline rates permits an understanding of the extent of the problem of low-value care, which in turn allows monitoring of the effect of initiatives such as Choosing Wisely on utilization rates over time.One Choosing Wisely item included by many specialty societies is the recommendation to avoid routinely performing preoperative testing (including chest radiography, echocardiography and cardiac stress tests) for patients undergoing low-risk surgery.^4–6 This recommendation was previously included in the 2007 American College of Cardiology/American Heart Association guidelines on perioperative cardiovascular evaluation for noncardiac surgery⁷ and was reconfirmed in a recent update.⁸ Avoiding preoperative investigations in this setting is supported by evidence that routine testing in patients undergoing low-risk surgery does not improve outcomes or change management and may lead to further unnecessary downstream testing, cancellation of surgery, and increases in patient anxiety and cost.^7,9–12 To date, neither the rate of preoperative testing across a large and diverse jurisdiction nor the degree of variation at regional and institutional levels, where data may be “actionable,” is well understood.The objectives of this study were to determine utilization rates of preoperative tests before hospital-based low-risk surgical procedures at the jurisdictional, regional and institutional level. In addition, we aimed to evaluate temporal trends of preoperative testing over a 5-year period. We hypothesized that there would be significant regional and institutional variation in preoperative cardiac testing before low-risk surgery and that patients with prior cardiac comorbidities would have a higher rate of preoperative testing than those without such comorbidities.     

Likelihood of coronary angiography among First Nations patients with acute myocardial infarction

Background:

Morbidity due to cardiovascular disease is high among First Nations people. The extent to which this may be related to the likelihood of coronary angiography is unclear. We examined the likelihood of coronary angiography after acute myocardial infarction (MI) among First Nations and non–First Nations patients.

Methods:

Our study included adults with incident acute MI between 1997 and 2008 in Alberta. We determined the likelihood of angiography among First Nations and non–First Nations patients, adjusted for important confounders, using the Alberta Provincial Project for Outcome Assessment in Coronary Heart Disease (APPROACH) database.

Results:

Of the 46 764 people with acute MI, 1043 (2.2%) were First Nations. First Nations patients were less likely to receive angiography within 1 day after acute MI (adjusted odds ratio [OR] 0.73, 95% confidence interval [CI] 0.62–0.87). Among First Nations and non–First Nations patients who underwent angiography (64.9%), there was no difference in the likelihood of percutaneous coronary intervention (PCI) (adjusted hazard ratio [HR] 0.92, 95% CI 0.83–1.02) or coronary artery bypass grafting (CABG) (adjusted HR 1.03, 95% CI 0.85–1.25). First Nations people had worse survival if they received medical management alone (adjusted HR 1.38, 95% CI 1.07–1.77) or if they underwent PCI (adjusted HR 1.38, 95% CI 1.06–1.80), whereas survival was similar among First Nations and non–First Nations patients who received CABG.

Interpretation:

First Nations people were less likely to undergo angiography after acute MI and experienced worse long-term survival compared with non–First Nations people. Efforts to improve access to angiography for First Nations people may improve outcomes.Although cardiovascular disease has been decreasing in Canada,¹ First Nations people have a disproportionate burden of the disease. First Nations people in Canada have a 2.5-fold higher prevalence of cardiovascular disease than non–First Nations people,² with hospital admissions for cardiovascular-related events also increasing.³The prevalence of cardiovascular disease in First Nations populations is presumed to be reflective of the prevalence of cardiovascular risk factors.^4–7 However, the disproportionate increase in rates of hospital admission suggests that suboptimal management of cardiovascular disease or its risk factors may also influence patient outcomes.^2,3 Racial disparities in the quality of cardiovascular care resulting in adverse outcomes have been documented, although most studies have focused on African-American, Hispanic and Asian populations.^8,9 As a result, it is unclear whether suboptimal delivery of guideline-recommended treatment contributes to increased cardiovascular morbidity and mortality among First Nations people.^10–12We undertook a population-based study involving adults with incident acute myocardial infarction (MI) to examine the receipt of guideline-recommended coronary angiography among First Nations and non–First Nations patients.^10–12 Among patients who underwent angiography, we sought to determine whether there were differences between First Nations and non–First Nations patients in the likelihood of revascularization and long-term survival.     

Effect of dietary pulse intake on established therapeutic lipid targets for cardiovascular risk reduction: a systematic review and meta-analysis of randomized controlled trials

Background:

Evidence from controlled trials encourages the intake of dietary pulses (beans, chickpeas, lentils and peas) as a method of improving dyslipidemia, but heart health guidelines have stopped short of ascribing specific benefits to this type of intervention or have graded the beneficial evidence as low. We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) to assess the effect of dietary pulse intake on established therapeutic lipid targets for cardiovascular risk reduction.

Methods:

We searched electronic databases and bibliographies of selected trials for relevant articles published through Feb. 5, 2014. We included RCTs of at least 3 weeks’ duration that compared a diet emphasizing dietary pulse intake with an isocaloric diet that did not include dietary pulses. The lipid targets investigated were low-density lipoprotein (LDL) cholesterol, apolipoprotein B and non–high-density lipoprotein (non-HDL) cholesterol. We pooled data using a random-effects model.

Results:

We identified 26 RCTs (n = 1037) that satisfied the inclusion criteria. Diets emphasizing dietary pulse intake at a median dose of 130 g/d (about 1 serving daily) significantly lowered LDL cholesterol levels compared with the control diets (mean difference −0.17 mmol/L, 95% confidence interval −0.25 to −0.09 mmol/L). Treatment effects on apolipoprotein B and non-HDL cholesterol were not observed.

Interpretation:

Our findings suggest that dietary pulse intake significantly reduces LDL cholesterol levels. Trials of longer duration and higher quality are needed to verify these results. Trial registration: ClinicalTrials.gov, no. {"type":"clinical-trial","attrs":{"text":"NCT01594567","term_id":"NCT01594567"}}NCT01594567.Abnormal blood concentrations of lipids are one of the most important modifiable risk factors for cardiovascular disease. Although statins are effective in reducing low-density lipoprotein (LDL) cholesterol levels, major health organizations have maintained that the initial and essential approach to the prevention and management of cardiovascular disease is to modify dietary and lifestyle patterns.^1–4Dietary non–oil-seed pulses (beans, chickpeas, lentils and peas) are foods that have received particular attention for their ability to reduce the risk of cardiovascular disease. Consumption of dietary pulses was associated with a reduction in cardiovascular disease in a large observational study⁵ and with improvements in LDL cholesterol levels in small trials.^6–8 Although most guidelines on the prevention of major chronic diseases encourage the consumption of dietary pulses as part of a healthy strategy,^2,3,9–13 none has included recommendations based on the direct benefits of lowering lipid concentrations or reducing the risk of cardiovascular disease. In all cases, the evidence on which recommendations have been based was assigned a low grade,^2,3,9–13 and dyslipidemia guidelines do not address dietary pulse intake directly.^1,4To improve the evidence on which dietary guidelines are based, we conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) of the effect of dietary pulse intake on established therapeutic lipid targets for cardiovascular risk reduction. The lipid targets were LDL cholesterol, apolipoprotein B and non–high-density lipoprotein (non-HDL) cholesterol.     

Mediterranean diets and metabolic syndrome status in the PREDIMED randomized trial

Background:

Little evidence exists on the effect of an energy-unrestricted healthy diet on metabolic syndrome. We evaluated the long-term effect of Mediterranean diets ad libitum on the incidence or reversion of metabolic syndrome.

Methods:

We performed a secondary analysis of the PREDIMED trial — a multicentre, randomized trial done between October 2003 and December 2010 that involved men and women (age 55–80 yr) at high risk for cardiovascular disease. Participants were randomly assigned to 1 of 3 dietary interventions: a Mediterranean diet supplemented with extra-virgin olive oil, a Mediterranean diet supplemented with nuts or advice on following a low-fat diet (the control group). The interventions did not include increased physical activity or weight loss as a goal. We analyzed available data from 5801 participants. We determined the effect of diet on incidence and reversion of metabolic syndrome using Cox regression analysis to calculate hazard ratios (HRs) and 95% confidence intervals (CIs).

Results:

Over 4.8 years of follow-up, metabolic syndrome developed in 960 (50.0%) of the 1919 participants who did not have the condition at baseline. The risk of developing metabolic syndrome did not differ between participants assigned to the control diet and those assigned to either of the Mediterranean diets (control v. olive oil HR 1.10, 95% CI 0.94–1.30, p = 0.231; control v. nuts HR 1.08, 95% CI 0.92–1.27, p = 0.3). Reversion occurred in 958 (28.2%) of the 3392 participants who had metabolic syndrome at baseline. Compared with the control group, participants on either Mediterranean diet were more likely to undergo reversion (control v. olive oil HR 1.35, 95% CI 1.15–1.58, p < 0.001; control v. nuts HR 1.28, 95% CI 1.08–1.51, p < 0.001). Participants in the group receiving olive oil supplementation showed significant decreases in both central obesity and high fasting glucose (p = 0.02); participants in the group supplemented with nuts showed a significant decrease in central obesity.

Interpretation:

A Mediterranean diet supplemented with either extra virgin olive oil or nuts is not associated with the onset of metabolic syndrome, but such diets are more likely to cause reversion of the condition. An energy-unrestricted Mediterranean diet may be useful in reducing the risks of central obesity and hyperglycemia in people at high risk of cardiovascular disease. Trial registration: ClinicalTrials.gov, no. ISRCTN35739639.Metabolic syndrome is a cluster of 3 or more related cardiometabolic risk factors: central obesity (determined by waist circumference), hypertension, hypertriglyceridemia, low plasma high-density lipoprotein (HDL) cholesterol levels and hyperglycemia. Having the syndrome increases a person’s risk for type 2 diabetes and cardiovascular disease.^1,2 In addition, the condition is associated with increased morbidity and all-cause mortality.^1,3–5 The worldwide prevalence of metabolic syndrome in adults approaches 25%^6–8 and increases with age,⁷ especially among women,^8,9 making it an important public health issue.Several studies have shown that lifestyle modifications,¹⁰ such as increased physical activity,¹¹ adherence to a healthy diet^12,13 or weight loss,^14–16 are associated with reversion of the metabolic syndrome and its components. However, little information exists as to whether changes in the overall dietary pattern without weight loss might also be effective in preventing and managing the condition.The Mediterranean diet is recognized as one of the healthiest dietary patterns. It has shown benefits in patients with cardiovascular disease^17,18 and in the prevention and treatment of related conditions, such as diabetes,^19–21 hypertension^22,23 and metabolic syndrome.²⁴Several cross-sectional^25–29 and prospective^30–32 epidemiologic studies have suggested an inverse association between adherence to the Mediterranean diet and the prevalence or incidence of metabolic syndrome. Evidence from clinical trials has shown that an energy-restricted Mediterranean diet³³ or adopting a Mediterranean diet after weight loss³⁴ has a beneficial effect on metabolic syndrome. However, these studies did not determine whether the effect could be attributed to the weight loss or to the diets themselves.Seminal data from the PREDIMED (PREvención con DIeta MEDiterránea) study suggested that adherence to a Mediterranean diet supplemented with nuts reversed metabolic syndrome more so than advice to follow a low-fat diet.³⁵ However, the report was based on data from only 1224 participants followed for 1 year. We have analyzed the data from the final PREDIMED cohort after a median follow-up of 4.8 years to determine the long-term effects of a Mediterranean diet on metabolic syndrome.     

Imaging for distant metastases in women with early-stage breast cancer: a population-based cohort study

Background:

Practice guidelines recommend that imaging to detect metastatic disease not be performed in the majority of patients with early-stage breast cancer who are asymptomatic. We aimed to determine whether practice patterns in Ontario conform with these recommendations.

Methods:

We used provincial registry data to identify a population-based cohort of Ontario women in whom early-stage, operable breast cancer was diagnosed between 2007 and 2012. We then determined whether imaging of the skeleton, thorax, and abdomen or pelvis had been performed within 3 months of tissue diagnosis. We calculated rates of confirmatory imaging of the same body site.

Results:

Of 26 547 patients with early-stage disease, 22 811 (85.9%) had at least one imaging test, and a total of 83 249 imaging tests were performed (mean of 3.7 imaging tests per patient imaged). Among patients with pathologic stage I and II disease, imaging was performed in 79.6% (10 921/13 724) and 92.7% (11 882/12 823) of cases, respectively. Of all imaging tests, 19 784 (23.8%) were classified as confirmatory investigations. Imaging was more likely for patients who were younger, had greater comorbidity, had tumours of higher grade or stage or had undergone preoperative breast ultrasonography, mastectomy or surgery in the community setting.

Interpretation:

Despite recommendations from multiple international guidelines, most Ontario women with early-stage breast cancer underwent imaging to detect distant metastases. Inappropriate imaging in asymptomatic patients with early-stage disease is costly and may lead to harm. The use of population datasets will allow investigators to evaluate whether or not strategies to implement practice guidelines lead to meaningful and sustained change in physician practice.Most women with newly diagnosed breast cancer present with early-stage, potentially curable disease.¹ Among patients whose disease is restricted to the breast and axillary lymph nodes, without signs or symptoms of metastatic disease, the likelihood of having radiologically evident metastases in pathologic stage I and II disease is about 0.2% and 1.2%, respectively.² This low frequency has not changed significantly, even with the increasing use of magnetic resonance imaging (MRI) and positron emission tomography.^2,3 For this reason, most provincial, national and international guidelines do not recommend imaging for all patients with early-stage breast cancer who are asymptomatic.^4–8Despite these evidence-based guidelines, imaging for distant metastases in patients with a new diagnosis of breast cancer remains common.^2,9–12 In response to the Choosing Wisely campaign of the American Board of Internal Medicine Foundation,¹³ the American Society of Clinical Oncology (ASCO) published its inaugural “top 5” list for choosing wisely in oncology.¹⁴ It recommended against routine imaging for staging purposes in women with early breast cancer, because “such imaging adds little benefit to patient care and has the potential to cause harm.”¹⁴ In 2014, Choosing Wisely Canada was launched in an effort to encourage physicians and patients to engage in conversations about unnecessary tests, treatments and procedures, to help ensure that patients receive the highest-quality care.¹⁵The ASCO Choosing Wisely recommendation¹⁴ is similar to the Cancer Care Ontario guideline,⁴ which has been in existence for over a decade. Whereas ASCO in its Choosing Wisely campaign recommends no imaging for patients with stage I or II disease, the Cancer Care Ontario guideline recommends no imaging for patients with stage I disease and a bone scan for those with stage II disease. A recent study at a large Canadian academic cancer centre showed that, despite publication of both a provincial guideline and the ASCO recommendations, most patients with primary operable (early-stage) breast cancer undergo imaging for distant metastases.¹⁰ We hypothesized that despite the provincial guideline, this practice may be more widespread. We undertook this population-based study to determine whether physician practice patterns in Ontario regarding imaging of patients with early-stage breast cancer are in keeping with the published Cancer Care Ontario guideline.     

Maternal cardiovascular disease after twin pregnancies complicated by hypertensive disorders of pregnancy: a population-based cohort study

Background:People whose singleton pregnancy is affected by hypertensive disorders of pregnancy (HDP) are at risk of future cardiovascular disease. It is unclear, however, whether this association can be extrapolated to twin pregnancies. We aimed to compare the association between HDP and future cardiovascular disease after twin and singleton pregnancies.Methods:We conducted a population-based retrospective cohort study that included nulliparous people in Ontario, Canada, 1992–2017. We compared the future risk of cardiovascular disease among pregnant people from the following 4 groups: those who delivered a singleton without HDP (referent) and with HDP, and those who delivered twins either with or without HDP.Results:The populations of the 4 groups were as follows: 1 431 651 pregnant people in the singleton birth without HDP group; 98 631 singleton birth with HDP; 21 046 twin birth without HDP; and 4283 twin birth with HDP. The median duration of follow-up was 13 (interquartile range 7–20) years. The incidence rate of cardiovascular disease was lowest among those with a singleton or twin birth without HDP (0.72 and 0.74 per 1000 person-years, respectively). Compared with people with a singleton birth without HDP, the risk of cardiovascular disease was highest among those with a singleton birth and HDP (1.47 per 1000 person-years; adjusted hazard ratio [HR] 1.81 [95% confidence interval (CI) 1.72–1.90]), followed by people with a twin pregnancy and HDP (1.07 per 1000 person-years; adjusted HR 1.36 [95% CI 1.04–1.77]). The risk of the primary outcome after a twin pregnancy with HDP was lower than that after a singleton pregnancy with HDP (adjusted HR 0.74 [95% CI 0.57–0.97]), when compared directly.Interpretation:In a twin pregnancy, HDP are weaker risk factors for postpartum cardiovascular disease than in a singleton pregnancy.

Cardiovascular disease has been shown to be the leading cause of death among women.^1–3 Classic risk factors for cardiovascular disease include obesity, diabetes mellitus, hypertension and family history of cardiovascular disease. ³ More recently, an association has been established between a history of hypertensive disorders of pregnancy (HDP) — gestational hypertension and pre-eclampsia — and future risk of cardiovascular disease.^1,4–11 Consequently, some recommend using a history of HDP for cardiovascular disease risk stratification in women.^3,12The leading hypothesis for the pathogenesis of HDP is that it results from abnormal placentation due to impaired trophoblast invasion,^13–16 resulting in reduced placental perfusion.^17–19 This, in turn, leads to abnormal secretion of the angiogenic factors soluble FMS-like tyrosine kinase 1 (sFlt1) and soluble endoglin (sEng),²⁰ which induce endothelial dysfunction and the clinical manifestations of HDP.^19,21–24 The mechanisms underlying the association between HDP and future cardiovascular disease are under debate.²⁵ One hypothesis is that HDP are merely a marker of underlying subclinical or clinical vascular risk factors that predispose a person to both HDP and future cardiovascular disease.A person who is pregnant with twins is at about 3–4 times higher risk of HDP than a person with a singleton pregnancy,^26–33 with rates of 14% and 5%, respectively.³⁴ The higher risk of HDP in twin pregnancies may be due to higher circulating sFlt1 and sEng owing to greater placental mass in twin pregnancies, ^35–37 and less related to the classic vascular risk factors for HDP in a singleton pregnancy. Therefore, a logical question is whether the established higher risk of future cardiovascular disease after singleton pregnancies with HDP also occurs in twin pregnancies with HDP. Limited data are available to answer this question.³⁸ In the current study, we aimed to test the hypothesis that the association between HDP and future cardiovascular disease is less pronounced in twin versus singleton pregnancies.     

Societal preferences for the return of incidental findings from clinical genomic sequencing: a discrete-choice experiment

Background:An important challenge with the application of next-generation sequencing technology is the possibility of uncovering incidental genomic findings. A paucity of evidence on personal utility for incidental findings has hindered clinical guidelines. Our objective was to estimate personal utility for complex information derived from incidental genomic findings.Methods:We used a discrete-choice experiment to evaluate participants’ personal utility for the following attributes: disease penetrance, disease treatability, disease severity, carrier status and cost. Study participants were drawn from the Canadian public. We analyzed the data with a mixed logit model.Results:In total, 1200 participants completed our questionnaire (available in English and French). Participants valued receiving information about high-penetrance disorders but expressed disutility for receiving information on low-penetrance disorders. The average willingness to pay was $445 (95% confidence interval [CI] $322–$567) to receive incidental findings in a scenario where clinicians returned information about high-penetrance, medically treatable disorders, but only 66% of participants (95% CI 63%–71%) indicated that they would choose to receive information in that scenario. On average, participants placed an important value ($725, 95% CI $600–$850) on having a choice about what type of findings they would receive, including receipt of information about high-penetrance, treatable disorders or receipt of information about high-penetrance disorders with or without available treatment. The predicted uptake of that scenario was 76% (95% CI 72%–79%).Interpretation:Most participants valued receiving incidental findings, but personal utility depended on the type of finding, and not all participants wanted to receive incidental results, regardless of the potential health implications. These results indicate that to maximize benefit, participant-level preferences should inform the decision about whether to return incidental findings.Clinical genomic sequencing technologies are on the verge of allowing individualized care at reasonable cost.¹ Patients and their families will soon receive information from clinical sequencing that has implications for clinical care, including information on consequences related to disease prognosis, treatment response or hereditary risk for disease.² Clinical sequencing can also generate incidental findings, which are clinically relevant genetic variants for disorders unrelated to the reason for ordering the genetic testing. The decision of whether to provide information about incidental findings is complex because such results will have varying clinical validity (whether the genetic variant causes the disorder) and utility (whether effective medical treatment is available for the disorder).^3,4 For example, although effective medical treatment may be available for some validated incidental findings, other incidental findings may not be validated as causing the disorder, and still others will be validated but not associated with effective treatment options.To address in part the challenges surrounding the return of incidental findings, the American College of Medical Genetics and Genomics published recommendations for reporting incidental findings from clinical sequencing.⁵ The statement lists a minimum of 56 genes that laboratories should examine, with results reported to patients through the managing physician. This list includes genes with high-penetrance mutations (i.e., a high proportion of individuals with the mutation will exhibit clinical symptoms) validated to be associated with disorders for which medical interventions are available.The original version of this statement did not “favour offering the patient a preference” for which results would be returned. The reasoning was that clinicians have a duty to prevent potential harm by telling patients about incidental findings. The working group that developed the recommendations further stated that it is impractical to provide the level of genetic counselling required for informed preference on all potential disorders.⁵ As such, the working group recommended that clinicians discuss with patients the possibility of receiving incidental findings from the list. It was argued that patient autonomy is preserved because patients can decline clinical sequencing if they prefer to not receive information about incidental findings.⁵ However, this rationale has been subject to debate because of its “all-or-none” nature, whereby patients must agree to receive information about incidental findings or clinical sequencing is not provided.^6–9 In April 2014, in response to the ongoing debate, the statement was amended to include an “opt-out” option for patients who do not want to receive information about incidental findings.¹⁰Notwithstanding the ethical debate, there is a lack of quantitative, preference-based economic evidence for the return of incidental genomic findings.⁸ It has been argued⁸ that this gap in evidence hindered development of the working group’s recommendation statement. More generally, evidence on preferences for the return of incidental findings is crucial for health policy, for health systems planning and for informing future lists that may include “many more genes.”⁸ We aimed to generate evidence on the personal utility that study participants from the Canadian public ascribe to the return of incidental genomic findings in the clinical setting. We chose participants from the general public because the public is the largest stakeholder in Canada’s publicly funded health care system.     

Regional collaborative home-based palliative care and health care outcomes among adults with heart failure

BackgroundInnovative models of collaborative palliative care are urgently needed to meet gaps in end-of-life care among people with heart failure. We sought to determine whether regionally organized, collaborative, home-based palliative care that involves cardiologists, primary care providers and palliative care specialists, and that uses shared decision-making to promote goal- and need-concordant care for patients with heart failure, was associated with a greater likelihood of patients dying at home than in hospital.MethodsWe conducted a population-based matched cohort study of adults who died with chronic heart failure across 2 large health regions in Ontario, Canada, between 2013 and 2019. The primary outcome was location of death. Secondary outcomes included rates of health care use, including unplanned visits to the emergency department, hospital admissions, hospital lengths of stay, admissions to the intensive care unit, number of visits with primary care physicians or cardiologists, number of home visits by palliative care physicians or nurse practitioners, and number of days spent at home.ResultsPatients who received regionally organized, collaborative, home-based palliative care (n = 245) had a 48% lower associated risk of dying in hospital (relative risk 52%, 95% confidence interval 44%–66%) compared with the matched cohort (n = 1172) who received usual care, with 101 (41.2%) and 917 (78.2%) patients, respectively, dying in hospital (number needed to treat = 3). Additional associated benefits of the collaborative approach included higher rates of clinician home visits, longer time to first hospital admission, shorter hospital stays and more days spent at home.InterpretationAdoption of a model of regionally organized, collaborative, home-based palliative care that uses shared decision-making may improve end-of-life outcomes for people with chronic heart failure.

Innovative models of collaborative, interdisciplinary palliative care that use shared decision-making to promote goal- and need-concordant care are urgently needed to meet rising demand among people with heart failure.^1,2 Between 2010 and 2015, 75% of people with heart failure in Ontario died in hospital, despite 70% of people preferring an out-of-hospital death and 90% preferring end-of-life health care delivery at home.^3–5 Most people also prioritize improvements in quality of life at the end of life over extension of life.⁶ Admission to hospital near the end of life is often perceived as undesirable and may result in the provision of unwanted care, whereas home visits near the end of life tend to focus on comfort and are associated with higher rates of death at home.^4,5,7,8 These preferences are recognized at a system level, such that avoidance of unwanted health care and at-home death are considered quality indicators for end-of-life care.^9–11 However, delivering high-quality care for people with heart failure who are near the end of their life is challenging because of their unpredictable illness course and limited capacity of specialist palliative care.^4,12–14Many studies, including a recent meta-analysis, have shown that home-based palliative care is associated with improved quality of life and symptoms, reduced health care use and a higher likelihood of a home death among people with heart failure. ^{4,8,12,13,15,16} However, only 32% of people with heart failure received home-based palliative care near the end of life in Ontario.^4,8 Several randomized controlled trials explored the effects of collaborative care models for people with heart failure; ^12–16 the results were mixed regarding quality of life, symptoms and health care use.^13,17–21 Some trials reported that palliative care resulted in improvements in quality of life and reductions in burdensome symptoms and hospital admissions, whereas others reported no change in these outcomes.¹³ Most studies were single centre and none evaluated a model of regional organization and in-person home visits as a scalable approach.Given the need to address end-of-life care gaps for people with heart failure, we sought to determine whether regionally organized, collaborative, home-based palliative care (CHPC) — involving cardiology, primary care and palliative care — was associated with increased rates of out-of-hospital death among adults who died with heart failure.     

Involving patients in cardiovascular risk management with nurse-led clinics: a cluster randomized controlled trial

Background

Preventive guidelines on cardiovascular risk management recommend lifestyle changes. Support for lifestyle changes may be a useful task for practice nurses, but the effect of such interventions in primary prevention is not clear. We examined the effect of involving patients in nurse-led cardiovascular risk management on lifestyle adherence and cardiovascular risk.

Methods

We performed a cluster randomized controlled trial in 25 practices that included 615 patients. The intervention consisted of nurse-led cardiovascular risk management, including risk assessment, risk communication, a decision aid and adapted motivational interviewing. The control group received a minimal nurse-led intervention. The self-reported outcome measures at one year were smoking, alcohol use, diet and physical activity. Nurses assessed 10-year cardiovascular mortality risk after one year.

Results

There were no significant differences between the intervention groups. The effect of the intervention on the consumption of vegetables and physical activity was small, and some differences were only significant for subgroups. The effects of the intervention on the intake of fat, fruit and alcohol and smoking were not significant. We found no effect between the groups for cardiovascular 10-year risk.

Interpretation

Nurse-led risk communication, use of a decision aid and adapted motivational interviewing did not lead to relevant differences between the groups in terms of lifestyle changes or cardiovascular risk, despite significant within-group differences.It is not clear if programs for lifestyle change are effective in the primary prevention of cardiovascular diseases. Some studies have shown lifestyle improvements with cardiovascular rehabilitation programs,^1–3 and studies in primary prevention have suggested small, but potentially important, reductions in the risk of cardiovascular disease. However, these studies have had limitations and have recommended further research.^4,5 According to national and international guidelines for cardiovascular risk management, measures to prevent cardiovascular disease, such as patient education and support for lifestyle change, can be delegated to practice nurses in primary care.^6–8 However, we do not know whether the delivery of primary prevention programs by practice nurses is effective. We also do no know the effect of nurse-led prevention, including shared decision-making and risk communication, on cardiovascular risk.Because an unhealthy lifestyle plays an important role in the development of cardiovascular disease,^9,10 preventive guidelines on cardiovascular disease and diabetes recommend education and counselling about smoking, diet, physical exercise and alcohol consumption for patients with moderately and highly increased risk.^6,11 These patients are usually monitored in primary care practices. The adherence to lifestyle advice ranges from 20% to 90%,^12–15 and improving adherence requires effective interventions, comprising cognitive, behavioural and affective components (strategies to influence adherence to lifestyle advice via feelings and emotions or social relationships and social supports).¹⁶ Shared treatment decisions are highly preferred. Informed and shared decision-making requires that all information about the cardiovascular risk and the pros and cons of the risk-reduction options be shared with the patient, and that the patients’ individual values, personal resources and capacity for self-determination be respected.^17–19 In our cardiovascular risk reduction study,²⁰ we developed an innovative implementation strategy that included a central role for practice nurses. Key elements of our intervention included risk assessment, risk communication, use of a decision aid and adapted motivational interviewing (Box 1).^19,21,22

Box 1.?Key features of the nurse-led intervention

• Risk assessment (intervention and control): The absolute 10-year mortality risk from cardiovascular diseases was assessed with use of a risk table from the Dutch guidelines (for patients without diabetes) or the UK Prospective Diabetes Study risk engine (for patients with diabetes).^6,23 Nurses in the control group continued to provide usual care after this step.
• Risk communication (intervention only): Nurses informed the patients of their absolute 10-year cardiovascular mortality risk using a risk communication tool developed for this study.^24–37
• Decision support (intervention only): Nurses provied support to the patients using an updated decision aid.²⁸ This tool facilitated the nurses’ interaction with the patients to arrive at informed, value-based choices for risk reduction. The tool provided information about the options and their associated relevant outcomes.
• Adapted motivational interviewing (intervention only): Nurses discussed the options for risk reduction. The patient’s personal values were elicited using adapted motivational interviewing.

In the present study, we investigated whether a nurse-led intervention in primary care had a positive effect on lifestyle and 10-year cardiovascular risk. We hypothesized that involving patients in decision-making would increase adherence to lifestyle changes and decrease the absolute risk of 10-year cardiovascular mortality.     

Longitudinal evaluation of physician payment reform and team-based care for chronic disease management and prevention

Background:

We evaluated a large-scale transition of primary care physicians to blended capitation models and team-based care in Ontario, Canada, to understand the effect of each type of reform on the management and prevention of chronic disease.

Methods:

We used population-based administrative data to assess monitoring of diabetes mellitus and screening for cervical, breast and colorectal cancer among patients belonging to team-based capitation, non–team-based capitation or enhanced fee-for-service medical homes as of Mar. 31, 2011 (n = 10 675 480). We used Poisson regression models to examine these associations for 2011. We then used a fitted nonlinear model to compare changes in outcomes between 2001 and 2011 by type of medical home.

Results:

In 2011, patients in a team-based capitation setting were more likely than those in an enhanced fee-for-service setting to receive diabetes monitoring (39.7% v. 31.6%, adjusted relative risk [RR] 1.22, 95% confidence interval [CI] 1.18 to 1.25), mammography (76.6% v. 71.5%, adjusted RR 1.06, 95% CI 1.06 to 1.07) and colorectal cancer screening (63.0% v. 60.9%, adjusted RR 1.03, 95% CI 1.02 to 1.04). Over time, patients in medical homes with team-based capitation experienced the greatest improvement in diabetes monitoring (absolute difference in improvement 10.6% [95% CI 7.9% to 13.2%] compared with enhanced fee for service; 6.4% [95% CI 3.8% to 9.1%] compared with non–team-based capitation) and cervical cancer screening (absolute difference in improvement 7.0% [95% CI 5.5% to 8.5%] compared with enhanced fee for service; 5.3% [95% CI 3.8% to 6.8%] compared with non–team-based capitation). For breast and colorectal cancer screening, there were no significant differences in change over time between different types of medical homes.

Interpretation:

The shift to capitation payment and the addition of team-based care in Ontario were associated with moderate improvements in processes related to diabetes care, but the effects on cancer screening were less clear.Health care systems with a strong primary care orientation have better health outcomes, lower costs and fewer disparities across population subgroups.¹ Countries around the world have been experimenting with reforms to improve the delivery of primary care, changing the way physicians are organized and paid. In the United States, several national organizations^2,3 and policy experts^4,5 have advocated a shift away from fee for service toward capitation or blended payments, and in 2015, the Centers for Medicare and Medicaid Services brought in blended payment in primary care, introducing a non–visit-based payment for chronic care management.⁶Patient-centred medical homes have provided an opportunity to transition physicians to new payment models, but they also necessitate changes in care delivery, including incorporation of team-based care, enhancement of access for patients, coordination of care and a focus on quality and safety.^7–9 Evidence suggests that team-based care is a particularly important element in improving the management and prevention of chronic disease and reducing related costs.¹⁰ Early evaluations of patient-centred medical home pilots were promising,^11,12 but a recent study of large-scale implementation showed limited improvements in the quality of chronic disease care and no reduction in health care utilization or total costs over 3 years.¹³Before 2002, primary care physicians in Ontario, Canada, were almost universally paid through a fee-for-service system. Over the past decade, more than three-quarters have transitioned to patient-centred medical homes.^14,15 About half of Ontario physicians working in patient-centred medical homes have shifted to blended capitation payments, with a portion of these physicians working in groups that also receive government funding for nonphysician health professionals to enable team-based care. However, about 40% of physicians in patient-centred medical homes still receive most of their income through fee-for-service payments. This natural health policy experiment offers a unique opportunity to compare the effectiveness of different payment models and team-based care. Early studies have shown small differences in the quality of cardiovascular¹⁶ and diabetes mellitus¹⁷ care between physicians receiving capitation payments and those receiving fee-for-service payments, but no studies have assessed changes in quality of care over time.We evaluated a large-scale transition of primary care physicians to blended capitation models and team-based care to understand the effect of each type of reform on chronic disease management and prevention over time.     

Effect of lung-protective ventilation with lower tidal volumes on clinical outcomes among patients undergoing surgery: a meta-analysis of randomized controlled trials

Background:In anesthetized patients undergoing surgery, the role of lung-protective ventilation with lower tidal volumes is unclear. We performed a meta-analysis of randomized controlled trials (RCTs) to evaluate the effect of this ventilation strategy on postoperative outcomes.Methods:We searched electronic databases from inception through September 2014. We included RCTs that compared protective ventilation with lower tidal volumes and conventional ventilation with higher tidal volumes in anesthetized adults undergoing surgery. We pooled outcomes using a random-effects model. The primary outcome measures were lung injury and pulmonary infection.Results:We included 19 trials (n = 1348). Compared with patients in the control group, those who received lung-protective ventilation had a decreased risk of lung injury (risk ratio [RR] 0.36, 95% confidence interval [CI] 0.17 to 0.78; I² = 0%) and pulmonary infection (RR 0.46, 95% CI 0.26 to 0.83; I² = 8%), and higher levels of arterial partial pressure of carbon dioxide (standardized mean difference 0.47, 95% CI 0.18 to 0.75; I² = 65%). No significant differences were observed between the patient groups in atelectasis, mortality, length of hospital stay, length of stay in the intensive care unit or the ratio of arterial partial pressure of oxygen to fraction of inspired oxygen.Interpretation:Anesthetized patients who received ventilation with lower tidal volumes during surgery had a lower risk of lung injury and pulmonary infection than those given conventional ventilation with higher tidal volumes. Implementation of a lung-protective ventilation strategy with lower tidal volumes may lower the incidence of these outcomes.Estimates suggest that more than 230 million patients undergo major surgical procedures worldwide each year.¹ Postoperative pulmonary complications, including lung injury, pneumonia and atelectasis, are common and a major cause of morbidity and death.^2–5 Thus, prevention of these complications has become a high priority of perioperative care.Mechanical ventilation is mandatory in patients undergoing surgical procedures during general anesthesia. Conventional mechanical ventilation with tidal volumes of 10 to 15 mL/kg has been advocated to prevent hypoxemia and atelectasis in anesthetized patients undergoing surgery.⁶ However, unequivocal evidence from experimental and clinical studies suggests that mechanical ventilation, especially the use of high tidal volumes, may cause or aggravate lung injury.^7–9 Mechanical ventilation using high tidal volumes can result in overdistention of alveoli that mainly causes ventilator-associated lung injury.¹⁰Lung-protective ventilation refers to the use of low tidal volumes and moderate to high levels of positive end-expiratory pressure, with or without a recruitment manoeuvre.¹¹ Lung-protective ventilation has been found to reduce morbidity and mortality among patients with acute lung injury and acute respiratory distress syndrome.^11,12 However, in anesthetized patients without the syndrome, the role of lung-protective ventilation remains unclear. Two previous meta-analyses addressing similar research questions have been published,^13,14 but the inclusion of observational studies compromised the reliability of the results. Recently, randomized controlled trials (RCTs) on the topic have reported conflicting results. We performed a meta-analysis of RCTs to evaluate the effect of lung-protective ventilation with lower tidal volumes on clinical outcomes in patients undergoing surgery.