Common infections and neuroimaging markers of dementia in three UK cohort studies

Abstract

AbstractIntroductionWe aimed to investigate associations between common infections and neuroimaging markers of dementia risk (brain volume, hippocampal volume, white matter lesions) across three population-based studies.MethodsWe tested associations between serology measures (pathogen serostatus, cumulative burden, continuous antibody responses) and outcomes using linear regression, including adjustments for total intracranial volume and scanner/clinic information (basic model), age, sex, ethnicity, education, socioeconomic position, alcohol, BMI, and smoking (fully adjusted model). Interactions between serology measures and APOE genotype were tested. Findings were meta-analysed across cohorts (Nmain=2632; NAPOE-interaction=1810).ResultsSeropositivity to JC virus associated with smaller brain volumes in basic models (ß=-3.89ml[-5.81,-1.97],padjusted<0.05); these were largely attenuated in fully adjusted models (ß=-1.59ml[-3.55,0.36], p=0.11). No other relationships were robust to multiple testing correction and sensitivity analyses, but several suggestive associations were observed.DiscussionWe did not find clear evidence for relationships between common infections and markers of dementia risk. Some suggestive findings warrant testing for replication.