Herpes zoster and major vascular events in a general population without prior cardiovascular event from Shizuoka Kokuho database

Abstract

Herpes zoster (HZ) is associated with a risk of cardiovascular disease (CVD), but findings may differ according to baseline risk profiles. We evaluated the association between HZ and CVD among adults without prior CVD. We used a municipal-level health insurance database in Japan. Adults aged 50–84 years without prior CVD were included. HZ was defined using ICD-10 diagnostic codes with concurrent antiviral prescription. The primary outcome was a composite of unstable angina pectoris, myocardial infarction, or stroke requiring hospitalization. Propensity score matching was performed and Cox proportional hazards models were used to estimate hazard ratios (HRs). Sensitivity analyses were conducted in individuals with Charlson Comorbidity Index ≥ 1. After propensity score matching, 94,269 individuals (20,575 HZ cases and 73,846 controls) were included. During a median follow-up of 58 months, 1,214 (1.3%) experienced the primary outcome. HZ was not significantly associated with increased risk (HR, 1.03; 95% CI, 0.90–1.18; p = 0.66). In a sensitivity analysis, HZ showed a non-significant trend toward higher risk (HR, 1.33; 95% CI, 0.90–1.96). In adults without prior CVD, HZ was not significantly associated with CVD events. However, a possible excess risk among individuals with comorbidities could not be excluded, supporting further evaluation in higher-risk populations.