Untangling the relationship between fat distribution, nutritional status and Parkinson's disease severity.

Background: Parkinson's disease (PD) is responsible for significant changes in body composition.

Aims: We aimed to test the association between PD severity and fat distribution patterns, and to investigate the potential modifier effect of nutritional status in this association.

Methods: We enrolled 195 PD subjects consecutively admitted to a university geriatric day hospital. All participants underwent comprehensive clinical evaluation, including assessment of total and regional body composition (dual-energy X-ray absorptiometry, DXA), body mass index, nutritional status (Mini-Nutritional Assessment, MNA), motor disease severity (UPDRS III), comorbidities, and pharmacotherapy.

Results: The fully adjusted linear regression model showed a negative association between UPDRS III and total body fat in kg and percentage (respectively, B - 0.79; 95% CI - 1.54 to - 0.05 and B - 0.55; 95% CI - 1.04 to - 0.05), percentage android fat (B - 1.07; 95% CI - 1.75 to - 0.39), trunk-leg fat ratio (B - 0.02; 95% CI - 0.04 to - 0.01), trunk-limb fat ratio (B - 0.01; 95% CI - 0.06 to - 0.01) and android-gynoid fat ratio (B - 0.01; 95% CI - 0.03 to - 0.01). After stratification by MNA score, all the parameters of android-like fat distribution resulted negatively associated (p < 0.001 for all) with UPDRS III, but only among subjects with a MNA < 23.5 (risk of malnutrition or malnutrition).

Conclusion: We found a negative association between severity of motor impairment and total fat mass in PD, more specific with respect to an android pattern of fat distribution. This association seems to be driven by nutritional status, and is significant only among patients at risk of malnutrition or with overt malnutrition.