While prior studies have shown racial/ethnic differences in cardiovascular (CV) outcomes
within private or mixed health care systems, it remains uncertain whether inequalities
in cardiovascular outcomes exist between different races and ethnicities in universal
health care contexts. We aimed to determine whether there are racial/ethnicity disparities
in long-term CV outcomes within a single-payer universal health care system.
METHODS AND RESULTS
The CARTaGENE study is a population-based prospective cohort study with enrollment
of 19,996 individuals between 40-69 years in 2009, in the province of Québec, Canada.
Participants residing in four large metropolitan areas were randomly chosen from the
provincial health insurance registry by strata of age, sex, and postal codes. Follow-up
was available up to 2016. For this analysis, we retained only participants without
prior known CV disease. The primary composite endpoint was time to the first CV event
or intervention (CV death, acute coronary syndrome, heart failure, coronary revascularization,
ischemic stroke, or peripheral vascular event or revascularization). We used unadjusted
and adjusted Cox proportional hazards to evaluate the association of self-defined
race/ethnicity with the primary endpoint. There were 17,802 eligible participants
with a mean age of 51 years (52.5% females) with 111,312 person-years of follow-up
(median follow-up of 6.6 years). South Asian (SA) participants had the highest prevalence
of diabetes mellitus (29%) and hypertension (32%). After adjustment for age and sex,
SA ethnicity was associated with a 95% relative increase in risk for CV events, while
East/Southeast Asian (ESA) ethnicity was associated with a 42% relative decrease in
risk for CV events compared to White participants. After further adjustment for socioeconomic
status and CV risk factors, ESA ethnicity remained associated with a similar decreased
CV risk. In contrast, the association of SA ethnicity with increased CV risk was attenuated
after full adjustment for baseline characteristics (Table 1).
Racial/ethnic disparities in long-term CV outcomes are present in a single-payer universal
healthcare setting. ESA ethnicity was associated with a lower risk of long-term CV
outcomes. Future studies are needed to corroborate the reduced risk of long-term major
CV events associated with ESA ethnicity. Understanding the reasons related to potential
CV protection with ESA ethnicity could facilitate endeavors to reduce long-term CV
outcomes in other races/ethnicities.