Temporal trends in cardiovascular disease risk factors among white, South Asian, Chinese and black groups in Ontario, Canada, 2001 to 2012: a population-based study

OBJECTIVES To determine ethnic-specific temporal trends in cardiovascular risk factors in Ontario between 2001 and 2012. DESIGN A population-based repeated cross-sectional study. SETTING Ontario, Canada. PARTICIPANTS 219,276 participants of the Canadian Community Health Survey (205,326 white, 5620 South Asian, 4368 Chinese and 3962 black) during the period 2001 to 2012. MAIN OUTCOME MEASURES Age-standardised ethnic-sex-specific prevalence of cardiovascular risk factors for three time periods: 2001-2004, 2005-2008 and 2009-2012 among Canada's four major ethnic groups: white, South Asian, Chinese and black. RESULTS During the study period, the prevalence of diabetes increased 2.3-fold (p = 0.0001) among South Asian males and 1.9-fold (p = 0.02) among black females. The prevalence of obesity (body mass index ≥ 30 kg/m(2)) increased over time across all ethnic groups, with the largest relative increases observed among males of Chinese (2.1-fold increase, p = 0.04) and black (1.7-fold increase, p = 0.06) descent. The prevalence of hypertension increased the most among black females. Smoking prevalence decreased by more than 20% among South Asian, Chinese and white females. Overall, South Asian males and black males and females showed the greatest declines in cardiovascular health over the study period. CONCLUSIONS We observed important ethnic differences in the temporal trends in cardiovascular risk factor profiles in Ontario. Awareness of the direction and magnitude of these risk factor trends may be useful in informing targeted strategies for preventing cardiovascular diseases in multiethnic populations.