Trends and Regional Variation in Prevalence of Cardiovascular Risk Factors and Association With Socioeconomic Status in Canada, 2005-2016

IMPORTANCE Cardiovascular disease remains the second leading cause of death in Canada. Monitoring and tracking the trends and disparities in major cardiovascular risk factors could provide benchmarks for future cardiovascular health strategies. OBJECTIVE To investigate the temporal trends, regional variations, and socioeconomic disparities in major cardiovascular risk factors in Canada from 2005 to 2016. Design, Setting, and Participants This repeated cross-sectional survey study included adults aged 20 years and older from 6 Canadian Community Health Survey cycles between 2005 and 2016. Cardiovascular risk factors included hypertension, diabetes, obesity, and current smoking. Socioeconomic status was measured using equivalized household income. Data analysis was performed from September 2019 to April 2020. EXPOSURES A total of 112 health regions and socioeconomic status. Main Outcomes and Measures Age- and sex-adjusted prevalence of hypertension, diabetes, obesity, and current smoking by year; health regions; and socioeconomic status. Absolute numbers were rounded to base 100 for confidentiality purposes, and percentages were based on weighted numbers. Slope index of inequality (SII) and relative index of inequality (RII) were calculated to assess absolute and relative socioeconomic inequalities, respectively. RESULTS A total of 670 000 respondents (329 000 [49.1%] men; 341 000 [50.9%] women) aged 20 years and older from 6 survey cycles were enrolled for this study. The largest age group was those aged 40 to 59 years (eg, 2005 cycle: 40.2% [95% CI, 39.9%-40.6%]). In the 2015/2016 cycle, the overall age- and sex-adjusted prevalence rates of hypertension, diabetes, obesity, and current smoking were 20.7% (95% CI, 20.4%-21.1%), 7.2% (95% CI, 7.0%-7.5%), 20.1% (95% CI, 19.7%-20.6%), and 17.8% (95% CI, 17.4%-18.2%), respectively. From 2005 to 2016, there was a significant increase in the prevalence of hypertension, diabetes, and obesity (eg, prevalence of diabetes in both sexes, 2005: 5.8% [95% CI, 5.6%-6.0%]; 2015/2016: 7.2% [95% CI, 7.0%-7.5%]; P < .001) but a significant decrease in the prevalence of current smoking (both sexes, 2005: 22.1% [95% CI, 21.7%-22.5%]; 2015/2016: 17.8% [95% CI, 17.4%-18.2%]; P < .001). The prevalence of all the risk factors varied widely across health regions (eg, obesity, Vancouver Health Service Delivery Area: 6.7% [95% CI, 4.5%-9.0%]; Miramichi Area: 36.8% [95% CI, 27.3%-46.3%]). In addition to obesity among men, all risk factors tended to be more common among those with lower income (eg, prevalence of hypertension in both sexes, 2015/2016, lowest income group: 23.2% [95% CI, 22.4%-24.0%]; highest income group: 18.4% [95% CI, 17.7%-19.1%]). The SII and RII indicated consistent absolute and relative socioeconomic inequalities in hypertension, diabetes, and current smoking over time (eg, RII for hypertension in both sexes, 2005: 1.25; 95% CI, 1.18-1.33; 2015/2016: 1.34; 95% CI, 1.26-1.43). However, the phenomenon of absolute and relative socioeconomic inequalities in obesity was only observed among women (eg, RII for 2015/2016 for obesity in women; 1.74 (95% CI, 1.56-1.93); men: 1.09; 95% CI, 0.99-1.21). CONCLUSIONS AND RELEVANCE During the study period, the prevalence of hypertension, diabetes, and obesity significantly increased, while the prevalence of current smoking significantly decreased. Geographic and socioeconomic gaps should be considered and addressed in future interventions and policies targeted at reducing these cardiovascular risk factors in Canada.