People with intellectual disability (particularly those with Down syndrome) have a higher risk of developing dementia than the general population. The varied presentation, the course, and available treatments are covered.

The life expectancy for people with intellectual disability is increasing due to advances in medical treatment and social care. However, significant discrepancies in life expectancy between people with intellectual disability and the general population remain, and there continues to be scope to close the inequality gap. This was confirmed in the recent 2021 Learning Disability Mortality Review (LeDeR) report. The standardised mortality ratio for people with intellectual disability ranges from 2–5, which draws a comparison against the general population. Those with additional comorbidities such as epilepsy, genetic syndromes, and functional impairments have a lower age of death. The leading causes of death in older adults (at or over 65 years of age) between 2018 and 2021 were reviewed in the 2021 LeDeR report. In comparison to the general population, a higher proportion of deaths in older intellectual disability adults were due to COVID-19 (coronavirus disease), cancers, and influenza or pneumonia. Unsurprisingly, dementia (in particular Alzheimer’s disease), cerebrovascular disease, chronic lower respiratory tract infections, and diseases of the urinary system were more common causes of death in older intellectual disability compared to that reported in their younger counterparts. This chapter explores the various issues associated with medicating older people.