Diagnosis and Clinical Relevance of Depression and Apathy in Alzheimer’s Disease

Abstract

Depression is one of the most common psychiatric disorders in Alzheimer’s disease (AD), and depression is associated with poorer quality of life, greater disability in activities of daily living, faster cognitive decline, and higher frequency of depression and burden in caregivers. Depression in AD in usually underdiagnosed, which may be related to the lack of validated diagnostic criteria and specific instruments to assess depression in dementia. Left untreated, major depression in AD may last for about 12 months. Apathy is increasingly recognized as a major behavioral disorder in neuropsychiatric diseases, but confusion still exists as to its proper definition and assessment and whether apathy should be considered a symptom or a syndrome. Nevertheless, a variety of instruments have been developed to rate the severity of apathy in dementia, and a structured clinical interview has been recently validated. Moreover, there is now international ­consensus for a set of standardized diagnostic criteria to diagnose apathy in AD. Finally, apathy is a significant predictor of faster functional, mood, and motor decline.