Inequities in statin adherence for primary prevention of cardiovascular disease: a historical cohort study in English primary care

Aims: Cardiovascular disease (CVD) is a leading global health concern. Statins are effective in reducing CVD risk, but suboptimal adherence limits their potential, yet recent data on this issue is limited, particularly regarding its association with socioeconomic deprivation and ethnicity.

Methods and results: We analysed English primary care data from the CPRD Aurum database for individuals aged 25 and older who started statin therapy between 1st January 2015 and 31st December 2019, with no prior CVD. Prescription-refill data were used to calculate the proportion of days covered (PDC) within 1 year. We used logistic regression to examine the relationship between socioeconomic deprivation or ethnicity and suboptimal statin adherence (defined as a PDC < 80%) adjusted for age, sex, year of statin prescription, deprivation or ethnicity, comorbidities, smoking, and BMI status. We also assessed whether sex might modify these associations. Among the 337 990 individuals included, 32.9% had suboptimal statin adherence. Deprivation was associated with an 11% increase in odds of suboptimal adherence (OR 1.11, 95% CI: 1.08–1.13). All ethnic minorities had higher odds of suboptimal adherence compared with the White group (Black: OR 2.00, 1.92–2.08; Mixed: OR 1.49, 1.41–1.56; South Asian: OR 1.35, 1.31–1.39). Men in deprived areas and of South Asian ethnicity background had higher odds of suboptimal adherence.

Conclusion: Suboptimal statin adherence remains a significant issue and a missed opportunity to reduce CVD burden. Adherence inequities exist, and targeted interventions are necessary to address these disparities.