Differences in nutritional status between very mild Alzheimer's disease patients and healthy controls

Abstract

Background: Studies on the systemic availability of nutrients and nutritional status in Alzheimer's disease (AD) are widely available, but the majority included patients in a moderate stage of AD.

Objective: This study compares the nutritional status between mild AD outpatients and healthy controls.

Methods: A subgroup of Dutch drug-naïve patients with mild AD (Mini-Mental State Examination (MMSE) ≥20) from the Souvenir II randomized controlled study (NTR1975) and a group of Dutch healthy controls were included. Nutritional status was assessed by measuring levels of several nutrients, conducting the Mini Nutritional Assessment (MNA®) questionnaire and through anthropometric measures.

Results: In total, data of 93 healthy cognitively intact controls (MMSE 29.0 [23.0-30.0]) and 79 very mild AD patients (MMSE = 25.0 [20.0-30.0]) were included. Plasma selenium (p < 0.001) and uridine (p = 0.046) levels were significantly lower in AD patients, with a similar trend for plasma vitamin D (p = 0.094) levels. In addition, the fatty acid profile in erythrocyte membranes was different between groups for several fatty acids. Mean MNA screening score was significantly lower in AD patients (p = 0.008), but not indicative of malnutrition risk. No significant differences were observed for other micronutrient or anthropometric parameters.

Conclusion: In non-malnourished patients with very mild AD, lower levels of some micronutrients, a different fatty acid profile in erythrocyte membranes and a slightly but significantly lower MNA screening score were observed. This suggests that subtle differences in nutrient status are present already in a very early stage of AD and in the absence of protein/energy malnutrition.

Keywords: Alzheimer's disease; fatty acids; healthy volunteers; micronutrients; nutritional status; protein-energy malnutrition.