Background: Statins are widely prescribed for the primary and secondary prevention of cardiovascular disease (CVD). Previous studies suggest inequalities in statin prescribing exist, but it is unclear where along the pathway, from recognition of risk through to prescribing and continuation, these inequalities manifest.
Objectives: To investigate trends and inequalities in statin use for the primary and secondary prevention of CVD between 1st April 2009 and 31st December 2021 in a UK population-based cohort study.
Methods: We conducted a historical cohort study of individuals aged 25 years and older using primary care data from a one-million-person random sample of the Clinical Practice Research Datalink (CPRD AURUM) linked to Hospital Episode Statistics (HES). We calculated the monthly proportion of current statin users for primary and secondary prevention. For primary prevention, we included individuals with no history of CVD and for secondary prevention, we included those with an existing CVD diagnosis. We used multivariable logistic regression to calculate odds ratios (OR) for the association between demographic factors and statin initiation for primary prevention (comprising those with a first CVD risk score above threshold for initiation) and secondary prevention.
Results: The monthly proportion of individuals prescribed a statin for primary prevention increased from 7.0% in July 2009 to 8.9% in November 2021; for secondary prevention the proportion increased from 64.3% to 68.6%. A spike in the monthly proportion of statin users was observed in March 2020 in both cohorts while a decline was seen during the COVID-19 lockdown periods. Prevalence of statin use for primary prevention was lowest in the most deprived groups. Among those eligible for primary prevention and with a CVD risk score above threshold for initiation, men had higher odds than women of receiving a first statin prescription within 28 days of a risk score OR 1.15 (95% CI, 1.10 - 1.21). People of African/African Caribbean ethnicity were associated with lower odds of statin initiation compared to White (OR 0.85, 95% CI; 0.74 – 0.98). Similarly, for secondary prevention, men had higher odds than women of receiving a statin prescription within 60 days of a CVD event (OR 1.34, 95% CI; 1.28 - 1.41) while the odds of statin initiation were lower for people of African/African Caribbean ethnicity compared to White (OR 0.77, 95% CI; 0.66-0.90) and for those in the most deprived socioeconomic group (OR 0.88, 95% CI; 0.81-0.95).
Conclusions: Inequalities in statin initiation and prevalence in terms of age, sex, ethnicity and deprivation have persisted over time. Future work is needed to investigate strategies to address disparities in statin prescribing and uptake.
