Risk of herpes zoster infection in men with varicocele.

Several diseases have been identified as stressful factors for herpes zoster (HZ) infection. In this study, we investigated the risk of HZ infection in men with varicocele. We enlisted the data of patients with newly diagnosed varicocele between 2000 and 2012 from the Taiwanese National Health Insurance Research Database as case cohort. Four control patients were matched as per age and index year to a case patient. HZ diagnosis was the primary end point, and the follow-up period was considered as the time interval from the index date to the main outcome, withdrawal from the National Health Insurance program, or end of the study (31 December 2013). In total, 8720 patients were recruited (1744 with varicocele and 6976 controls); the overall mean age was 36 years. Majority (85%) of the participants were 20-49 years old. HZ incidence was higher in patients with varicocele (5.60 per 1,000 person-years) than in the control group (4.01 per 1,000 person years). Patients with varicocele were 1.37 times more likely to develop HZ than the controls after adjustment. Compared with the control cohort, the adjusted hazards ratio (HR) of the varicocele cohort was higher in patients younger than 49 years old (adjusted HR = 1.60). Men with varicocele had a higher risk of HZ development than those without varicocele, particularly those aged ≤49 years. Thus, stress from varicocele cannot be ignored in young men.