Prevalence of depression, anxiety, and apathy symptoms across dementia stages: A systematic review and meta-analysis.

Depression, anxiety, and apathy symptoms are highly prevalent across dementia stages. There is no evidence of any changes in prevalence of affective symptom as the illness progresses. Evaluation methods and cultural difference may explain some of the variance, suggesting further investigation of factors that may influence the report of symptoms, such as carer psychosocial characteristics, and more cross-cultural studies are needed.