Influence of nutritional status on cognitive, functional and neuropsychiatric deficits in Alzheimer's disease

Nutrition is an important issue for elderly people, especially in patients with dementia. It is also related to clinical outcome, such as cognition, autonomy and behavior. The present study investigated the role of nutritional status on cognitive, functional and neuropsychiatric deficits in patients with Alzheimer's disease (AD). Forty-nine patients underwent neuropsychological, nutritional and neuropsychiatric assessments. The sample was divided into at risk of malnutrition (21 patients) and well-nourished (28 patients) according to the Mini Nutritional Assessment (MNA) score. The groups were similar for clinical and demographic variables, except for MNA score and age. The mean body mass index (BMI) was higher than the normal range. Patients at risk of malnutrition showed greater impairment, both in simple and instrumental activities of daily living (ADL and IADL) and a more severe ideomotor praxis deficit than well-nourished patients. Neuropsychiatric symptoms showed significant differences in hallucination, apathy, aberrant motor behavior and night-time subscales of Neuropsychiatric Inventory (NPI). These symptoms were more severe in patients at risk of malnutrition. Logistic regression analysis showed that malnutrition was an important risk factor for the onset of apathy. We hypothesized that changes in dietary habits and intake and the onset of these disorders reflect the involvement of a common neuroanatomical network.