Risk Factors Measured Around Age 60 as Predictors of Dementia Around Age 80 in the U.S.

The number of older adults living with dementia in the United States and worldwide continues to rise. Identifying elevated dementia risk decades before potential onset can help individuals prepare and enable healthcare providers and policymakers to target resources that may delay onset or mitigate consequences. Using nationally representative data from the U.S. Health and Retirement Study (1992-2016), we estimated the probability of dementia at around age 80 as a function of 110 risk factors measured at around age 60, using a recently developed and validated probabilistic dementia measure and longitudinal regression models. Poor physical health, low cognitive ability, fewer than 12 years of education, and greater functional limitations at around age 60 were the strongest predictors of dementia at age 80. Additional predictors included being born in the Southeastern U.S., lacking private health insurance, non-veteran status, having poor vision or hearing, limited work history, disability, diabetes, body mass index ≥ 35, prior stroke, and both alcohol abstention and heavy drinking. Several predictors, such as geographic origin, veteran status, and work history, have received limited attention in prior prediction research. Future research should examine whether these candidate predictors represent causal risk factors rather than simply associations.