Objectives: Analysis of variations of nutritional status in relation to psycho-functional conditions in elderly patients with mild to moderate Alzheimer's disease (AD) by means of bioelectrical impedance vector analysis (BIVA).
Design: Cross-sectional study.
Setting: Alzheimer Center, SS. Trinità Hospital, Cagliari (Italy).
Participants: 83 free-living patients (29 men, 54 women) with mild-moderate Alzheimer's disease, aged 66 to 96 years, and 91 age-matched controls (37 men and 54 women).
Measurements: Nutritional status was evaluated by anthropometry (weight, height, waist and upper arm circumferences, triceps skinfold; body mass index, BMI; arm muscle area, AMA); Mini Nutritional Assessment, MNA®; bioelectrical impedance vector analysis, BIVA. Psycho-functional status was assessed by the Mini Mental State Examination (MMSE), Geriatric Depression Scale (GDS), Activities of Daily Living (ADL), and Instrumental Activities of Daily Living (IADL).
Results: Compared to the control groups, patients with Alzheimer's disease had a worse psycho-functional and nutritional status. BIVA detected lower body cell mass in Alzheimer's patients with respect to controls (men: T²= 23.4; women: T²=27.3; p<0.01), as well as in the female patients with lower levels of IADL and MMSE (respectively, T²= 8.0; T²=7.4; p<0.05). In patients with AD, a worse psycho-functional status was associated with obesity.
Conclusion: The psycho-functional decline of patients with AD is related to body composition variations, with a relative increase of fat mass with respect to the muscle component. The BIVA technique distinguished patients from controls and patients with different levels of cognitive decline. Therefore, it is a suitable tool for the screening and monitoring of nutritional status in Alzheimer's disease.