The risk of herpes zoster virus infection in patients with depression A longitudinal follow-up study using a national sample cohort

The features of herpes zoster share some commonalities with depression, including decreased cellular immunity, a close correlation with nutritional status, and a higher prevalence in the elderly population. We aimed to assess the association between herpes zoster infection and depression in the Korean population. We performed a longitudinal follow-up study of a nationwide sample cohort derived from the Korean National Health Insurance Service database. Individuals diagnosed with depression between 2002 and 2013 (n=58,278) as well as matched controls (n= 233,112), with both groups comprising 34.3% male and 65.7% female subjects, were extracted and analyzed for the presence of herpes zoster infection. Depression was diagnosed based on the International Classification of Diseases tenth revision (ICD-10) codes F31-F39, while herpes zoster was diagnosed as ICD-10 B02. The rate of herpes zoster infection was higher in the depressed group (6.8% [3967/58,278]) than in the control group (6.3% [14,689/233,122], P<.001). The adjusted hazard ratio (HR) for herpes zoster infection was 1.09 (95% CI: 1.05-1.13) in the depressed group (P<.001). Subgroup analyses revealed that the adjusted HRs for herpes zoster infection were higher only in women younger than 60 years among participants with depression. These HRs were 1.13 (95% CI: 1.02-1.25; P=.016) in women younger than 40 years and 1.11 (95% CI: 1.04-1.17; P<.001) in women aged 40-59 years. Depression is a predictor of herpes zoster infection in Korean women younger than 60 years.