IMMIGRATION STATUS AND SEX DIFFERENCES IN PRIMARY CARDIOVASCULAR DISEASE PREVENTION: A RETROSPECTIVE STUDY OF 5 MILLION ADULTS

Cardiovascular disease is a leading cause of death and disability globally. Cardiovascular disease incidence varies by immigration status and sex. Sex differences in the quality of primary cardiovascular preventive care have been described, but whether these differences vary by immigration status is less understood. Intersectionality theory suggests that sex, immigration status and ethnic origin interact synergistically, potentially leading to differences in cardiovascular care and outcomes among men and women based on their immigration status. Immigrants of diverse ethnicities represent 22% of the Canadian population. We evaluated whether immigration status modified the association between sex and the quality of primary cardiovascular disease prevention using a population-based cohort in Ontario, Canada.

We used administrative databases to identify community-dwelling adults (aged ≥ 40 years) without prior cardiovascular disease residing in Ontario on January 1, 2011. We evaluated care in the preceding three years: screening for hyperlipidemia and diabetes in those not previously diagnosed; medication use to control hypertension, hyperlipidemia, or diabetes in those with a previous diagnosis; diabetes control (HbA1c < 7%); and visits to a family physician or a specialist. We calculated the absolute prevalence difference (APD) between women and men for each metric stratified by immigration status, and then determined the difference-in-differences for immigrants compared to long-term residents. Our sample population included 5.3 million adults (19% immigrants), with receipt of each metric ranging from 55% to 90%. Among immigrants, women were more likely than men to be screened for diabetes (APD 11.5% [95% confidence interval 11.1, 11.8]) and hyperlipidemia (APD 10.8% [10.5, 11.2]), to be treated with medications for hypertension (APD 3.5% [2.4, 4.5]), diabetes (APD 2.1% [0.7, 3.6]) and hyperlipidemia (APD 1.8% [0.5, 3.1]), and to have at least one visit to a primary care provider (APD 7.3% [6.9, 7.7]) and specialist (APD 14.2% [14.0, 14.5]) (Table 1 and Figure 1). Among long-term residents, findings were similar except women were less likely than men to be treated with medications for hypertension (APD -2.8% [-3.4, -2.2]) and hyperlipidemia (APD -3.5% [-4.0, -3.0]) (Table 1 and Figure 1).

Women had equal or better primary cardiovascular preventive care than men, with similar findings among immigrants and long-term residents treated in a healthcare setting with universal health coverage. The overall quality of primary preventive care can be improved for all adults, and future research should evaluate the impact of the observed sex differences in care on cardiovascular disease incidence.