Herpes zoster as a potential clinical marker of undiagnosed Type 2 diabetes in older adults: a retrospective cohort study.

Abstract

Herpes zoster has been associated with immune and metabolic disturbances; however, its relationship with newly diagnosed Type 2 diabetes mellitus (T2DM) remains unclear. This study aimed to investigate whether herpes zoster may serve as a clinical marker of previously unrecognized T2DM among people aged 65-84 years. We conducted a retrospective cohort study using de-identified electronic health records from TriNetX (2006-24). Patients aged 65-84 years with a diagnosis of herpes zoster (ICD-10 code B02) were compared with age-matched patients without herpes zoster. Propensity score matching was applied to balance baseline characteristics. The primary outcome was newly diagnosed T2DM. Hazard ratios and 95% confidence intervals were estimated using Cox proportional hazards models within the TriNetX platform. After propensity score matching and exclusion of patients who developed the outcome prior to the predefined follow-up window, 16 175 herpes zoster patients and 16 336 matched controls were included. During 1 year of follow-up, the cumulative incidence of T2DM was 2.362% in the herpes zoster group and 0.343% in controls. Herpes zoster was associated with a significantly higher likelihood of newly diagnosed T2DM (hazard ratio, 6.517; 95% confidence interval, 4.923-8.627). Herpes zoster was associated with newly diagnosed T2DM in older people. These findings support the hypothesis that herpes zoster may serve as an early clinical marker of previously unrecognized T2DM. Prospective studies are warranted to clarify temporal relationships and to determine whether targeted glycemic evaluation is clinically beneficial.