Unravelling sex disparities in statin dose titration patterns in primary care

Introduction Statins are widely recommended by clinical guidelines for the prevention and management of cardiovascular disease. While guidelines make no sex-specific recommendations, studies have shown that women are less likely than men to be prescribed high-intensity statins at initiation and to achieve cholesterol target values. However, the existing literature lacks evidence in sex comparison of statin treatment patterns in real-world clinical practice. Purpose This study aims to examine sex differences in titration patterns of statin therapy over a ten-year period in a Dutch primary care setting. Methods Data on statin dispensing was extracted from electronic healthcare data banks between 2011-2020. Poisson regression with robust standard errors was used to estimate risk ratios (RR) with 95% confidence intervals (CI) of sex differences in statin uptitration (defined as an increase in statin intensity or the addition of ezetimibe to statin therapy). Analyses were adjusted for age, socio-economic status and Low-Density Lipoprotein (LDL) cholesterol levels at initiation and were stratified by age group, history of cardiovascular disease at initiation and intensity of the first dispensed statin. Missing data were imputed with multiple imputation. Results We identified 72,110 new users of statin therapy (46% women) with a mean age of 65 years old. Most patients were dispensed a moderate-intensity statin at initiation (87% of women; 84% of men), followed by high-intensity (8% of women; 13% of men) and low-intensity statins (5% of women; 3% of men). Overall, 17% of women and 19% of men were uptitrated, with median times to uptitration of 535 days (Interquartile range (IQR) 181 – 1216) in women and 559 days (187 – 1240) in men. The adjusted RR of being uptitrated in women versus men was 0.92 (95% CI 0.87 – 0.97) for those without a history of CVD and 0.82 (0.73 – 0.92) for those with a history of CVD (pvalue for interaction = 0.02). Sex differences in statin uptitration were 0.90 (0.84 – 0.97) in those 40-60 years old, 0.91 (0.84 – 0.97) in those 60-70 years old, and 0.95 (0.93 – 1.00) in the older age category (70-99 years old). Conclusion Among new-statin users, women receive lower statin intensities than men and are less likely to be uptitrated than men.