A systematic review on the evidence of misdiagnosis in dementia and its impact on accessing dementia care

Background Whilst there is a drive to increase diagnosis rates in dementia, there is a lack of attention on getting a correct and timely subtype diagnosis. For people with a rarer subtype of dementia, getting the correct diagnosis, and subsequent care, might be more difficult than for people aged 65+ presenting with the more common symptoms of Alzheimer's disease dementia. Thus, the aim of this mixed-method systematic review was to synthesise the evidence base on misdiagnosis of dementia. Methods Misdiagnosis in dementia was defined as either receiving an initial incorrect dementia subtype diagnosis or receiving an incorrect non-dementia diagnosis. Post-mortem assessments of subtype diagnosis were excluded. Nine databases were searched in June 2023, with screening of titles and abstracts and consequent full texts completed independently by two researchers. Findings were synthesised using narrative synthesis. Results Twenty studies were included. Studies were categorised into four themes: (i) Factors associated with delayed diagnosis or misdiagnosis; (ii) Difficulties related to the diagnostic process; (iii) Economic consequences of misdiagnosis; and (iv) Experiences of delayed diagnosis or help-seeking. People with Lewy Body dementia or behavioural variant fronto-temporal dementia were found to experience longer diagnosis times and often incorrect initial diagnoses. Whilst evidence is limited regarding the economic impacts, evidence from the US points towards increased economic costs of misdiagnosis. Conclusions There is an urgent need to investigate the rates and emotional and economic impacts of misdiagnosis on people with dementia, their carers, and the health and social care system. Advancing the evidence base is crucial to reduce misdiagnosis and inform clinical practice.