Herpes Zoster Does Not Increase the Risk of Neurodegenerative Dementia: A Case-Control Study

OBJECTIVE: This study was conducted to evaluate the association between neurodegenerative dementia and herpes zoster infection (HZI) using a national sample cohort. METHODS: From the national cohort study conducted by the Korean National Health Insurance Service, we extracted data for patients with neurodegenerative dementia and for 1:4 matched control participants and searched the patient histories for HZI. RESULTS: The adjusted odds ratio (OR) for HZI was 0.90 (95% CI = 0.84-0.97) in the dementia group. According to the subgroup analysis, the adjusted OR for HZI was 0.91 (95% confidence interval [CI] = 0.83 -1.00) in the < 80 years old group, 0.88 (95% CI = 0.78 -1.00) in the ≥ 80 years old group, 0.77 (95% CI = 0.66-0.89) in men and 0.96 (95% CI = 0.88 -1.05) in women. CONCLUSIONS: We concluded that HZI does not increase the risk of neurodegenerative dementia in individuals of any age or of either sex.