Intellectual disabilities and risk of dementia: A Korean population-based cohort study

This retrospective cohort study assessed the risk of all-cause dementia, Alzheimer’s disease (AD), and vascular dementia (VaD) in individuals with intellectual disabilities compared to those without. Using data from the Korean National Disability Registry and National Health Insurance Service, individuals over 40 who underwent health examinations in 2009 were followed until 2020. Cox proportional hazards models estimated hazard ratios (HRs) for dementia outcomes, adjusting for confounders. Over a mean 8-year follow-up, 161 dementia, 111 AD, and 22 VaD cases occurred among individuals with intellectual disabilities. Adjusted HRs for all-cause dementia, AD, and VaD were 5.75, 5.23, and 4.66, respectively, compared to those without intellectual disabilities. The risk was especially elevated among those aged 40–64 years (P for interaction <0.01). In conclusion, individuals with intellectual disabilities have a significantly higher risk of dementia, particularly at younger ages, highlighting the need for increased awareness and targeted healthcare strategies.