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Background: Variations in the prevalence of traditional cardiac risk factors only partially account for geographic variations in the incidence of cardiovascular disease. We examined the extent to which preventive ambulatory health care services contribute to geographic variations in cardiovascular event rates., Methods: We conducted a cohort study involving 5.5 million patients aged 40 to 79 years in Ontario, Canada, with no hospital stays for cardiovascular disease as of January 2008, through linkage of multiple population-based health databases. The primary outcome was the occurrence of a major cardiovascular event (myocardial infarction, stroke or cardiovascular-related death) over the following 5 years. We compared patient demographics, cardiac risk factors and ambulatory health care services across the province's 14 health service regions, known as Local Health Integration Networks (LHINs), and evaluated the contribution of these variables to regional variations in cardiovascular event rates., Results: Cardiovascular event rates across LHINs varied from 3.2 to 5.7 events per 1000 person-years. Compared with residents of high-rate LHINs, those of low-rate health regions received physician services more often (e.g., 4.2 v. 3.5 mean annual family physician visits, p value for LHIN-level trend = 0.01) and were screened for risk factors more often. Low-rate LHINs were also more likely to achieve treatment targets for hypercholes-terolemia (51.8% v. 49.6% of patients, p = 0.03) and controlled hypertension (67.4% v. 53.3%, p = 0.04). Differences in patient and health system factors accounted for 74.5% of the variation in events between LHINs, of which 15.5% was attributable to health system factors alone., Interpretation: Preventive ambulatory health care services were provided more frequently in health regions with lower cardiovascular event rates. Health system interventions to improve equitable access to preventive care might improve cardiovascular outcomes., (© 2017 Canadian Medical Association or its licensors.)

The purpose of this study was to examine utilization and growth in echocardiography among the general population of Ontario between 2001 and 2009. The age- and sex-adjusted rates of echocardiography grew from 39.1 per 1,000 persons in 2001 to 59.9 per 1,000 persons in 2009, for an annual rate of increase of 5.5%. Repeat echocardiograms increased at a rate of 10.6% per year and accounted for 25.3% of all procedures in 2009 as compared to 18.5% in 2002. While significant increases in echocardiography utilization were observed, opportunities may exist to improve the clinical utility of the echocardiograms performed in Ontario., (Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Objectives: We evaluated whether appropriateness and baseline risk of cardiac catheterization varied according to regional intensity of invasive therapy after acute myocardial infarction (AMI), and whether AMI mortality varied according to invasive intensity regions., Background: Marked regional variations exist in cardiac invasive procedure use after AMI within the U.S., Methods: We performed an analysis of 44,639 Medicare fee-for-service beneficiaries hospitalized with AMI between 1998 and 2001. Invasive procedure intensity was determined based on overall cardiac catheterization rates for Medicare enrollees. Cardiac catheterization appropriateness was determined by the American College of Cardiology/American Heart Association classification and baseline risk was estimated using the GRACE (Global Registry of Acute Coronary Events) risk score. The primary outcomes of the study were cardiac catheterization use within 60 days and 3-year mortality after hospital admission., Results: Higher invasive intensity regions were more likely to perform cardiac catheterizations on class I patients (appropriate) (RR 1.38, 95% confidence interval [CI] 1.27 to 1.48), class II patients (equivocal) (RR 1.42, 95% CI 1.31 to 1.53), and class III patients (inappropriate) (RR 1.29, 95% 0.97 to 1.67) compared with low-intensity regions after adjusting for patient and physician characteristics. The overall cardiac catheterization use was 5.2% lower for each increase in GRACE risk decile, and this relationship was observed similarly in all regions. Risk-standardized mortality rates of AMI patients at 3 years were not substantially different between regions., Conclusions: Although higher-risk patients and those with more appropriate indications may have the most to benefit from an invasive strategy after AMI, we found that higher-invasive regions do not differentiate procedure selection based on the patients' appropriateness or their baseline risks.

Background: Guidelines advocate for antimicrobial prophylaxis for prevention of bacterial endocarditis. Our objective was to explore physicians' perspectives regarding the importance of echocardiography in the evaluation and management of endocarditis prophylaxis., Methods: A total of 260 cardiologists and 300 family physicians practicing in Ontario, Canada, were surveyed. Our main outcome measures were physician ratings of the importance of a murmur, echocardiogram findings, echocardiogram comments, comorbid conditions, guidelines, patient insistence, and medicolegal concerns on the decision to recommend prophylaxis, as well as the degree of echocardiographically detected mitral valve abnormality required prior to recommending prophylaxis., Results: The survey response rate was 62%. Echocardiographic findings were rated by 81% of physicians as the most important factor influencing the decision to provide prophylaxis. Conversely, only 27% of physicians placed similar importance on clinical findings. Family physicians relied more heavily on echocardiographic than on clinical findings when supporting endocarditis prophylaxis recommendations. On average, prophylaxis was recommended for moderate to severe regurgitation in a normal valve and mild regurgitation in a mildly abnormal structural mitral valve. Physicians who reported greater reliance on echocardiographic findings advocated for prophylaxis at lower echocardiographic thresholds than did those who reported greater reliance on murmur detection for endocarditis prophylaxis decisions., Conclusions: Physicians strongly support the use of echocardiography in endocarditis prophylaxis decision making. However, the importance of echocardiography relative to other factors varies across physician specialties. Further studies must evaluate the role of echocardiography in the assessment and management of antimicrobial endocarditis prophylaxis to assist in the development of clear clinical guidelines.

Background: While various community and hospital characteristics have been demonstrated to have an impact on individual cardiovascular outcomes, the extent to which such factors account for inter-regional and interhospital outcome variations following acute myocardial infarction (AMI) remains unknown., Objectives: To examine the impact of community and hospital factors on individual AMI outcomes and procedure use, and to determine the extent to which such characteristics account for inter-regional and interinstitutional AMI outcome and procedure variations across Canada., Methods: Patients hospitalized with AMI between April 1, 1997, and March 31, 2000, across Canada were examined. The community and hospital characteristics studied included three indicators of socioeconomic status, two indicators of ethnicity, rural-urban status of residence, hospital academic affiliation, and the presence or absence of on-site angiography or revascularization capabilities at the admitting institution. Outcomes included in-hospital mortality, one-year cardiac readmissions and 30-day revascularization rates post-AMI. All analyses were adjusted for age, sex and age-sex interaction. The relationships between community/hospital factors and individual outcomes were examined using random-effects hierarchical logistic regression analysis, while the relationships between community/hospital characteristics and inter-regional/hospital risk-adjusted outcomes were examined using least squares regression and the coefficient of determination (r2)., Results: After adjusting for demographic factors, a patient's neighbourhood socioeconomic status was inversely correlated with the likelihood of death and downstream cardiac readmissions (P<0.001); patients residing in lower educated regions were less likely to receive revascularization post-AMI (P<0.001). Patients living in regions with higher concentrations of new immigrants and/or visible minorities, as well as those admitted to academically affiliated hospitals or hospitals with on-site procedural capacity, had fewer cardiac readmissions (P<0.001) and greater use of revascularization post-AMI (P<0.001) after adjusting for age and sex. Despite their associations with outcomes on an individual patient level, community and hospital factors explained no more than 7% of the variation in the risk-adjusted outcomes across hospitals or regions. Finally, adjustments for community and hospital factors and procedure use, beyond adjustments for age and sex alone, had marginal impact on a province's risk-adjusted outcomes., Conclusions: While community and hospital factors are important determinants of individual outcomes after AMI, they account for only a minimal degree of outcome variation across regions. Further studies are required to examine whether AMI outcome variations in Canada are explained by differences in patient clinical profiles and/or by differences in the decision-making behaviours of providers across jurisdictions.

Context: The benefits of cardiovascular therapies such as statins for secondary prevention have been well documented, although they may not be optimally used in patients most likely to benefit. Ideally, aggressiveness in the use of these beneficial therapies should correlate with baseline cardiovascular risk., Objective: To examine the association between physicians' treatment aggressiveness and baseline cardiovascular risk., Design, Setting, and Patients: Retrospective cohort study incorporating the use of multiple linked health care administrative databases covering more than 1.4 million elderly residents of Ontario. We included 396,077 patients aged 66 years or older who had a history of cardiovascular disease or diabetes while undergoing medical treatment and who were alive on April 1, 1998. Baseline cardiovascular risk was derived using a risk-adjustment index in which we modeled probability of death after 3 years of follow-up., Main Outcome Measure: Likelihood of statin use, stratified by baseline cardiovascular risk, after adjusting for age, sex, socioeconomic status, and rural or urban residence., Results: Only 75,617 patients (19.1%) in this secondary prevention cohort were prescribed statins. In patients 66 to 74 years old, the adjusted probabilities of statin prescription were 37.7%, 26.7%, and 23.4% in the categories of low, intermediate, and high baseline risk, respectively. The likelihood of statin prescription was 6.4% lower (adjusted odds ratio, 0.94; 95% confidence interval, 0.93-0.95) for each year of increase in age and each 1% increase in predicted 3-year mortality risk. The influence of age also interacted synergistically with baseline risk on the prescription of statins (P<.001)., Conclusions: We found that prescription of statins diminished progressively as baseline cardiovascular risk and future probability of death increased. Since the benefits of a therapy are dependent on the baseline risk, the maximum benefits of statins may not be fully realized until implementation of therapy includes patients at highest risk.

Background: Socioeconomic status appears to be an important predictor of coronary angiography use after acute myocardial infarction. One potential explanation for this is that patients with lower socioeconomic status live in neighbourhoods near nonteaching hospitals that have no catheterization capacity, few specialists and lower volumes of patients with acute myocardial infarction. This study was conducted to determine whether the impact of socioeconomic status on angiography use would be lessened by considering variations in the supply of services., Methods: We examined payment claims for physician services, hospital discharge abstracts and vital status data for 47 036 patients with acute myocardial infarction admitted to hospitals in Ontario between April 1994 and March 1997. Neighbourhood income of each patient was obtained from Canada's 1996 census. Using multivariate hierarchical logistic regression and adjusting for baseline patient and physician factors, we examined the interaction among hospital and regional characteristics, socioeconomic status and angiography use in the first 90 days after admission to hospital for acute myocardial infarction., Results: Within each hospital and geographic subgroup, crude rates of angiography rose progressively with increases in neighbourhood income. After adjusting for sociodemographic, clinical and physician characteristics, hospitals with on-site angiography capacity (adjusted odds ratio [OR] 1.88, 95% confidence interval [CI] 1.52-2.33), those with university affiliations (adjusted OR 1.60, 95% CI 1.27-2.01) and those closest to tertiary institutions (adjusted OR 1.57, 95% CI 1.32-1.87) were all associated with higher 90-day angiography use after acute myocardial infarction. However, the relative impact of socioeconomic status on 90-day angiography use was similar whether or not hospitals had on-site procedural capacity (interaction term p = 0.68), had university affiliations (interaction term p = 0.99), were near tertiary facilities (interaction term p = 0.67) or were in rural or urban regions (interaction term p = 0.90)., Interpretation: Socioeconomic status was as important a predictor of angiography use in hospitals with ready access to cardiac catheterization facilities as it was in those without. The socioeconomic gradient in the use of angiography after acute myocardial infarction cannot be explained by the distribution of specialists or tertiary hospitals.

Objective: To examine how physicians in Ontario, Canada, have altered their referral patterns for coronary angiography after acute myocardial infarction (AMI) over time., Design: Retrospective analysis of multilinked administrative data., Setting: Province of Ontario, Canada., Patients: 146 365 Ontario AMI patients hospitalised between 1 April 1992 and 31 March 1999., Main Outcome Measures: Utilisation trends of coronary angiography among all patients, as well as within six subgroups: elderly (versus young), women (versus men), high (versus low) risk of 30 day mortality, high (versus low) socioeconomic status, cardiology (versus non-cardiology) attending physician specialty, and hospitals with (versus without) onsite revascularisation capacity. Cox proportional hazard models were adjusted for variations in patient, physician, and hospital characteristics over time., Results: Angiography rates in Ontario increased from 23.2% in 1992 to 35.5% in 1999 (p < 0.0001). Increases in utilisation of coronary angiography were most pronounced among the elderly (12.4-24.3% v 39.3-54.4% for non-elderly patients, p < 0.0001), the affluent (24.6-38.7% v 22.0-32.3% for less affluent patients, p = 0.01), and those tended to by cardiologists (32.0-47.1% v 20.3-30.1% for non-cardiology attending specialties, p < 0.0001) after adjusting for changes in baseline patient, physician, and hospital characteristics over time., Conclusions: Despite universal health care availability, not all patients benefited equally from increases in service capacity for coronary angiography after AMI in Ontario. Wider implementation of data monitoring and explicit management systems may be required to ensure that appropriate utilisation of cardiac services is allocated to patients who are most in need.

Objectives: The goal of our study was to examine how age and gender affect the use of coronary angiography and the intensity of cardiac follow-up care within the first year after acute myocardial infarction (AMI). Another objective was to evaluate the association of age, gender and treatment intensity with five-year survival after AMI., Background: Utilization rates of specialized cardiac services inversely correlate with age. Gender-specific practice patterns may also vary with age in a manner similar to known age-gender survival differences after AMI., Methods: Using linked population-based administrative data, we examined the association of age and gender with treatment intensity and long-term survival among 25,697 patients hospitalized with AMI in Ontario between April 1, 1992, and December 31, 1993. A Cox proportional hazards model was used to adjust for socioeconomic status, illness severity, attending physician specialty and admitting hospital characteristics., Results: After adjusting for baseline differences, the relative rates of angiography and follow-up specialist care for women relative to men, respectively, fell 17.5% (95% confidence interval [CI], 13.6 to 21.3, p < 0.001) and 10.2% (95% CI, 7.1 to 13.2, p < 0.001) for every 10-year increase in age. Conversely, long-term AMI survival rates in women relative to men improved with increasing age, such that the relative survival in women rose 14.2% (95% CI, 10.1 to 17.5, p < 0.001) for every 10-year age increase., Conclusions: Gender differences in the intensity of invasive testing and follow-up care are strongly age-specific. While care becomes progressively less aggressive among older women relative to men, survival advantages track in the opposite direction, with older women clearly favored. These findings suggest that biology is likely to remain the main determinant of long-term survival after AMI for women.