Neuropsychological performance predicts decision-making abilities in Chinese older persons with mild or very mild dementia.

OBJECTIVE To explore the relationship of the 4 decision-making abilities (Understanding, Appreciation, Reasoning, and Expressing a Choice) and neuropsychological performance in patients with very mild and mild dementia. METHODS Chinese subjects were recruited from local social centres and residential hostels for elderly people in Hong Kong. Clinical diagnosis was made by experienced geriatric psychiatrists. A battery of neuropsychological tests that assesses general cognitive abilities, verbal memory, executive function, concept formation, and auditory and visual attention, was administered. Mental capacity to consent to treatment was assessed using the Chinese version of the MacArthur Competence Assessment Tool - Treatment. RESULTS Fifty participants with very mild or mild dementia were compared with 42 cognitively intact subjects. After controlling for the effects of age and education, stepwise linear regression analysis demonstrated that the 4 decision-making abilities correlated with different neuropsychological test performances, which predicted 45% of the common variance for Understanding, 39% for Appreciation, 20% for Reasoning, and 30% for Expressing a Choice. The Reasoning score was only predicted by the Category Verbal Fluency Test (β = 0.4, p = 0.01). CONCLUSION Neuropsychological test performance differentially predicted different decision-making abilities in older patients with mild or very mild dementia.