Transition to dementia in people with late‐life depression compared to older people with other mental illnesses

Abstract

AbstractBackgroundDepression is highly prevalent in dementia and has been reported as a risk factor for dementia. Given the growth of the older population and a potential link between depression and dementia, it is important to understand the health profiles and related service use, especially for possible treatment and prevention strategies. The objectives of this study were to examine the transition to dementia and to compare the health and service use profiles in people with late‐life depression and older people with other mental illness and.MethodA retrospective population‐based study using 13 years of linked health data including 55,717 people aged 65 or older hospitalised with depression and 104,068 people aged 65 or older hospitalised with other mental illness. Logistic regression and cox proportional hazard models were used to analyse the risk of dementia.ResultThe most prominent differences between the two groups were the rates of delirium and self‐harm with a six times lower rate of delirium in people with late‐life depression and an eight times higher rate of self‐harm compared to those with other mental illness. Inpatients with late‐life depression had an increased risk of subsequent dementia by 12% compared to inpatients with other mental illnesses. Besides late‐life depression, only two other conditions, diabetes and cerebrovascular accidents, were associated with an increased risk for dementia.ConclusionInpatients with late‐life depression have an increased risk of dementia compared to older inpatients with other mental illness. Our findings highlight the importance of clinical management and prevention of self‐harm and delirium. The growing ageing population, along with the high prevalence of mental illness and comorbidities in older adults, has significant implications for the planning and equipping of health services to meet the needs of affected individuals.