TY - JOUR

T1 - Antiherpetic medication and incident dementia

T2 - Observational cohort studies in four countries

AU - Schnier, Christian

AU - Janbek, Janet

AU - Williams, Linda

AU - Wilkinson, Tim

AU - Laursen, Thomas M.

AU - Waldemar, Gunhild

AU - Richter, Hartmut

AU - Kostev, Karel

AU - Lathe, Richard

AU - G Haas, Jürgen

PY - 2021

Y1 - 2021

N2 - Background and purpose: Several epidemiological studies from Taiwan, all using the same data resource, found significant associations between herpes virus infection, antiherpetic medication, and subsequent dementia. We conducted a multicenter observational cohort study using health registry data from Wales, Germany, Scotland, and Denmark to investigate potential associations between antiherpetic medication and incident dementia, and also to comprehensively investigate such associations broken down according to medication type and dose, type of herpes virus, and dementia subtype. Methods: A total of 2.5 million individuals aged 65 years or more were followed up using linked electronic health records in four national observational cohort studies. Exposure and outcome were classified using coded data from primary and secondary care. Data were analyzed using survival analysis with time-dependent covariates. Results: Results were heterogeneous, with a tendency toward decreased dementia risk in individuals exposed to antiherpetic medication. Associations were not affected by treatment number, herpes subtype, dementia subtype, or specific medication. In one cohort, individuals diagnosed with herpes but not exposed to antiherpetic medication were at higher dementia risk. Conclusions: Short-term antiherpetic medication is not markedly associated with incident dementia. Because neither dementia subtype nor herpes subtype modified the association, the small but significant decrease in dementia incidence with antiherpetic administration may reflect confounding and misclassification.

AB - Background and purpose: Several epidemiological studies from Taiwan, all using the same data resource, found significant associations between herpes virus infection, antiherpetic medication, and subsequent dementia. We conducted a multicenter observational cohort study using health registry data from Wales, Germany, Scotland, and Denmark to investigate potential associations between antiherpetic medication and incident dementia, and also to comprehensively investigate such associations broken down according to medication type and dose, type of herpes virus, and dementia subtype. Methods: A total of 2.5 million individuals aged 65 years or more were followed up using linked electronic health records in four national observational cohort studies. Exposure and outcome were classified using coded data from primary and secondary care. Data were analyzed using survival analysis with time-dependent covariates. Results: Results were heterogeneous, with a tendency toward decreased dementia risk in individuals exposed to antiherpetic medication. Associations were not affected by treatment number, herpes subtype, dementia subtype, or specific medication. In one cohort, individuals diagnosed with herpes but not exposed to antiherpetic medication were at higher dementia risk. Conclusions: Short-term antiherpetic medication is not markedly associated with incident dementia. Because neither dementia subtype nor herpes subtype modified the association, the small but significant decrease in dementia incidence with antiherpetic administration may reflect confounding and misclassification.

KW - Alzheimer disease

KW - antiviral

KW - cognitive decline

KW - herpes

KW - vascular dementia

U2 - 10.1111/ene.14795

DO - 10.1111/ene.14795

M3 - Journal article

C2 - 33657269

AN - SCOPUS:85102616511

VL - 28

SP - 1840

EP - 1848

JO - European Journal of Neurology

JF - European Journal of Neurology

SN - 1351-5101

IS - 6

ER -