Vulnerabilities to Health Disparities and Statin Use in the REGARDS (Reasons for Geographic and Racial Differences in Stroke) Study

BACKGROUND Statins may be underutilized in certain vulnerable populations, but the effect of cumulative vulnerabilities within 1 individual is not well described. We sought to determine the likelihood of receiving statins with an increasing number of vulnerabilities in an individual, after controlling for factors known to influence health services utilization. METHODS AND RESULTS We identified 18 216 participants from the REGARDS (Reasons for Geographic and Racial Differences in Stroke) study who had a statin indication or who were taking statins, as verified by pill bottle review. Statin use was assessed with respect to 5 major vulnerability domains alone and in combination: older age, black race, female sex, high area-level poverty, and lack of health insurance. The study included 5286 white men, 4180 black men, 2791 white women, and 4194 black women; 5.6% of the sample had no vulnerabilities, 20.6% had 1 vulnerability, 29.2% had 2 vulnerabilities, 27.3% had 3 vulnerabilities, and 17.3% had 4 or 5 vulnerabilities. All race-sex groups were less likely than white men to use statins; prevalence of use was 0.80 in black women with reference to white men (P<0.0001). In both unadjusted and adjusted models, as the number of vulnerabilities increased, statin use steadily decreased. After adjusting for factors that influence health services utilization, compared with those without any vulnerabilities, statin use prevalence was 0.91, 0.83, 0.74 and 0.68 (P<0.0001) in those with 1, 2, 3, and 4 or 5 vulnerabilities, respectively. CONCLUSIONS Participants with more simultaneously occurring vulnerabilities experienced the greatest disparities in statin use. Black women and those without health insurance were at particularly high risk of underutilization.