Vulnerability as a Driver: How Medical Risk Factors Explain Sociodemographic and Environmental Disparities in Dementia Risk among Older Germans (2016-2018)

Anna-Victoria Holtz , German Center for Neurodegenerative Diseases (DZNE)
Igor Akushevich, Duke University
Gabriele Doblhammer, University of Rostock

Due to population ageing and an increased number of individuals with dementia in Germany, it is crucial to understand disparities in dementia risk. This study investigates whether sociodemographic and environmental disparities in dementia risk can be explained by medical risk factors or produce disparities independently. By distinguishing between exposure (prevalence) and vulnerability (association strength), we assess how risk factors contribute to the observed disparities. Using longitudinal health claims data linked with district-level (NUTS-3) environmental data from Germany, we analyzed 250,000 older individuals between 2016-2018. Dementia incidence was assessed via Cox proportional hazards models stratified by age group and adjusted separately for sex and area-level premature mortality, neighborhood socioeconomic status, and GDP. We decomposed disparities into exposure and vulnerability effects for heart diseases, diabetes, depression, cerebrovascular disease, Parkinson’s disease, head injuries, and antipsychotic use. Dementia risk was higher for individuals living in areas with high premature mortality, neighborhood disadvantage, and lower GDP, with disparities decreasing with age. Men aged 75–79 had lower dementia risk than women, but this reversed among those aged 80–84. Medical risk factors explained these disparities, especially in the 75–79 group. Heart diseases contributed most to environmental disparities, while diabetes and depression explained mostly the sex disparity. Most disparities were driven by vulnerability rather than exposure effects, particularly for heart diseases. The association strength between medical risk factors and dementia is a key driver of socioenvironmental disparities in dementia risk. Targeted prevention addressing heart diseases, diabetes and depression, especially in disadvantaged population groups, may decrease these disparities.

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 Presented in Session 73. Cognitive Aeging, Dementia and Life Course Determinants of Cognitive Health