OBJECTIVE: To estimate the incidence of cardiovascular events (CVE) among secondary prevention patients in Japan
METHODS: A retrospective cohort study examined adults initiating either a statin or ezetimibe from 1/1/2006-5/31/2014 in the Japan Medical Data Center database (2005-2015). The first observed statin or ezetimibe prescription defined the index date. Patients had ≥12 months of pre- and post-index date plan enrollment. Patients with atherosclerotic cardiovascular disease (ASCVD) during the pre-index period were identified, including the subgroup of patients with ≥25 % statin up-titration in the follow-up period. Incidence of CVE, defined as a new inpatient claim for myocardial infarction (MI), unstable angina, stroke, coronary revascularization procedure, heart failure (HF), transient ischemic attack, or peripheral artery disease was reported.
RESULTS: 5,302 patients with previous ASCVD were included (mean [SD] age: 55.7 [9.5] years, 63.8% males). Diabetes (59.6%) and hypertension (59.5%) were the most prevalent comorbidities, pre-index. 69.8% of patients received moderate intensity statins and 0.8% received both statins and ezetimibe. Post-index date, 8.1% had any new CVE over a mean follow-up of 2.8 years; stroke (2.4%), MI (2.2%) and HF (1.5%) were the most common events; incident rates of these events per 1000 person-years of follow-up were 8.6 (stroke), 7.9 (MI) and 5.5 (HF). Among ASCVD patients who up titrated statin (N=385), 8.6% had a new CVE after statin up titration over a mean follow-up of 2.7 years; MI (2.9%), stroke (2.3%) and HF (1.6%) were the most common CVEs. Incidence rates of these events per 1000 person-years in patients with ASCVD and statin up-titration were 10.6 (MI), 8.7 (stroke) and 5.8 (HF).
CONCLUSIONS: In a real world Japanese cohort with ASCVD, many patients still had recurrent CVEs despite receiving statins and/or ezetimibe. These findings highlight a continued unmet medical need in the area of secondary CVE prevention in Japanese patients.