Mental and Behavioral Disturbances in Dementia: Findings From the Cache County Study on Memory in Aging

TLDR

The study screened 5,092 adults aged 65+ for dementia, and 1,002 participants (329 with dementia, 673 without) underwent comprehensive neuropsychiatric examinations and were rated using the Neuropsychiatric Inventory. Among 329 dementia cases, 61 % exhibited at least one mental or behavioral disturbance—most frequently apathy, depression, or agitation—occurring almost four times as often as in non‑demented participants, with only modest variation across dementia types, underscoring that most dementia patients experience such disturbances and that they warrant routine assessment and treatment.

Abstract

OBJECTIVE: The authors report findings from a study of 5,092 community residents who constituted 90% of the elderly resident population of Cache County, Utah. METHOD: The 5,092 participants, who were 65 years old or older, were screened for dementia. Based on the results of this screen, 1,002 participants (329 with dementia and 673 without dementia) underwent comprehensive neuropsychiatric examinations and were rated on the Neuropsychiatric Inventory, a widely used method for ascertainment and classification of dementia-associated mental and behavioral disturbances. RESULTS: Of the 329 participants with dementia, 214 (65%) had Alzheimer's disease, 62 (19%) had vascular dementia, and 53 (16%) had another DSM-IV dementia diagnosis; 201 (61%) had exhibited one or more mental or behavioral disturbances in the past month. Apathy (27%), depression (24%), and agitation/aggression (24%) were the most common in participants with dementia. These disturbances were almost four times more common in participants with dementia than in those without. Only modest differences were observed in the prevalence of mental or behavioral disturbances in different types of dementia or at different stages of illness: participants with Alzheimer's disease were more likely to have delusions and less likely to have depression. Agitation/aggression and aberrant motor behavior were more common in participants with advanced dementia. CONCLUSIONS: On the basis of their findings in this large community population of elderly people, the authors conclude that a wide range of dementia-associated mental and behavioral disturbances afflict the majority of individuals with dementia. Because of their frequency and their adverse effects on patients and their caregivers, these disturbances should be ascertained and treated in all cases of dementia.