No evidence that herpes zoster is associated with increased risk of dementia diagnosis.

Objective: To investigate whether herpes zoster (HZ) was associated with subsequent increased risk of dementia diagnosis.

Methods: We conducted a historical cohort study using primary care electronic health records from the Clinical Practice Research Datalink in the United Kingdom. Individuals with incident HZ aged ≥40 years from 2000 to 2017 were matched with up to four individuals without HZ by age, sex, primary care practise and calendar time.