Sex-Based Utilization of Guideline Recommended Statin Therapy and Cardiovascular Disease Outcomes: A Primary Prevention Healthcare Network Registry

BackgroundIn the US, women have similar cardiovascular death rates than men. Less is known about sex differences in statin use for primary prevention and associated atherosclerotic cardiovascular disease (ASCVD) outcomes. MethodsStatin prescriptions using electronic health records were examined in patients without ASCVD (myocardial infarction (MI), revascularization or ischemic stroke) between 2013-2019. Guideline-directed statin intensity (GDSI) at index and follow-up visits were compared among sexes across ASCVD risk groups, defined by pooled-cohort equation. Cox regression hazard ratios (HR) [95% CI] were calculated for statin use and outcomes (myocardial infarction, stroke/transient ischemic attack (TIA), and all-cause mortality) stratified by sex. Interaction terms (statin and sex) were applied. ResultsAmong 282,298 patients, (mean age [~] 50 years) 17.1% women and 19.5% men were prescribed any statin at index visit. Time to GDSI was similar between sexes, but the proportion of high-risk women on GDSI at follow-ups was lower compared to high-risk men (2-years: 27.7 vs 32.0%, and 5-years: 47.2 vs 55.2%, p<0.05). When compared to GDSI, no statin use was associated with higher risk of MI and ischemic stroke/TIA amongst both sexes. High-risk women on GDSI had a lower risk of mortality (HR=1.39 [1.22-1.59]) versus men (HR=1.67 [1.50-1.86]) of similar risk (p value interaction=0.004). ConclusionIn a large contemporary healthcare system, there was underutilization of statins across both sexes in primary prevention. High-risk women were less likely to be initiated on GDSI compared with high-risk men. GDSI significantly improved the survival in both sexes regardless of ASCVD risk group. Future strategies to ensure continued use of GDSI, specifically among women, should be explored.