Proprotein convertase subtilisin/kexin type 9 inhibitor utilization and low-density lipoprotein-cholesterol control in familial hypercholesterolemia

Background: Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors were approved in August 2015 as an adjunct to maximally tolerated statin treatment in those with familial hypercholesterolemia (FH). Objective: To assess PCSK9 inhibitor utilization patterns and cholesterol control in the high-risk FH population. Methods: This study was a retrospective analysis of a large administrative database that includes privately insured and Medicare Advantage patients. Individuals with diagnosis codes for FH from October 2016–September 2019 were identified. Differences in PCSK9 inhibitor utilization between various groups were evaluated using multivariable logistic regression. Results: During the study period, 1:371 people enrolled in medical/pharmacy plans had a diagnosis of FH. While 62.5% (n = 33,649) had medication fills for statins (without PCSK9 inhibitors), only 2.0% (n = 1062) had medication fills for PCSK9 inhibitors (with or without other medications). Compared to men, women were more likely to be untreated (OR 1.23, 95% confidence interval (CI):1.18–1.28, p < 0.01) but more likely to be treated with PCSK9 inhibitors (OR 2.18, 95%CI:1.90–2.49, p < 0.01). Compared to those younger than 55 years of age, older individuals were more likely to be treated (OR 1.64, 95%CI:1.56–1.72, p < 0.01) but less likely to be treated with PCSK9 inhibitors (OR 0.40, 95%CI:0.34–0.47, p < 0.01). Lastly, those with household incomes ≥$40,000 were more likely to be treated with PCSK9 inhibitors than those with lower household incomes (OR 1.69, 95%CI:1.41–2.02, p < 0.01). Conclusion: PCSK9 inhibitor utilization in FH remains low. Significant differences exist based on demographic factors. Female sex, higher household incomes, and younger age were associated with increased PCSK9 inhibitor utilization.