The Association between Vitamin D and Incident Herpes Zoster: A UK Biobank Study

Abstract

Background: Although vitamin D has immunomodulatory effects, any association with herpes zoster (HZ) is unclear. Aim: To explore the association between vitamin D status and the risk of incident HZ in adults in the UK. Design and setting: We conducted a cohort study including participants from UK Biobank, who had at least one vitamin D testing result with linked primary care electronic health records. Methods: The primary exposure was vitamin D status, categorised as deficient (< 25 nmol/L), insufficient (25–50 nmol/L) or sufficient (≥ 50 nmol/L). The secondary exposures were self-reported vitamin D supplementation at baseline assessment and vitamin D prescription records. The outcome was diagnosed incident HZ, identified from linked primary care or hospital inpatient records. We used Weibull regression, adjusting for potential confounders including demographic factors, comorbidities and immunosuppression. Results: We included 177,572 eligible participants in our analysis with mean follow-up time of 10.1 (SD=1.9) years. No evidence showed that low vitamin D was associated with a higher incidence of HZ, compared with people with sufficient vitamin D (deficient: adjusted hazard ratio [HR] = 0.99, 95% confidence interval [CI] = 0.90–1.10; insufficiency: RR = 1.03, CI = 0.96–1.10.) We found no evidence that vitamin D supplementations or receiving vitamin D prescription was associated with HZ incidence (supplementation: HR = 0.88, CI = 0.67–1.16; prescription: HR = 1.11, CI = 0.91–1.34.) Conclusion: We observed no association of vitamin D status, supplementation or prescription with incident HZ. No evidence supported vitamin D supplementation as a strategy to prevent HZ.