Statin, Ezetimibe, or Fibrate Initiation and Subsequent Use for the Primary and Secondary Prevention of Cardiovascular Diseases among Japanese Patients Aged ≥55 Years: A Nationwide Cohort Study

Abstract

The use of lipid-modifying agents (LMAs) other than statins has rarely been reported in real clinical settings. We aimed to compare the initiation and subsequent use of LMA classes for prevention of cardiovascular diseases. Using the national claims database, this retrospective cohort study was conducted on patients aged ≥55 years who initiated to use statins, ezetimibe, or fibrates between Fiscal Years (FYs) 2014 and 2017 as the first pharmacotherapy for dyslipidemia in Japan. A permissible gap for defining persistence was set as the median days of supply of a class to an individual. Kaplan-Meier estimates were calculated for rates. Cohorts for primary prevention without/with risk and secondary prevention comprised 1307438, 908378, and 503059 initiators for statins; 44116, 34206, and 11373 for ezetimibe; and 124511, 96380, and 27751 for fibrates. The persistence rates declined shortly after the therapy initiation regardless of the classes, which was approximately 50% at 1 year for any class for primary prevention without risk. A notable sex difference in terms of persistence rates was observed only for statins of secondary prevention. The restarting rates were similar between prevention settings: approximately 50-60% for statins and 30-40% for ezetimibe and fibrates 1 year after first discontinuation. For ezetimibe and fibrates, approximately 10% of initiators were added or switched to statins within 1 year of initiation. Collectively, any class tended to be discontinued early and some restarted; however, there were some unique classes. The findings are useful for improvement of dyslipidemia therapy.