Dietary patterns and non-motor symptoms in Parkinson’s : a cross-sectional analysis

Objective: Evidence-based treatment for non-motor symptoms in Parkinson’s (PD) is limited. Lifestyle-based improvements including dietary changes may be a potential management strategy. To investigate the extent to which three dietary indices (Mediterranean-DASH Diet Intervention for Neurodegenerative Delay (MIND), Dietary Inflammation Index (DII), and Healthy Diet Indicator (HDI-2020) are associated with overall and individual non-motor symptom severity amongst individuals with Parkinson’s. Methods: An exploratory cross-sectional analysis of dietary (food frequency questionnaire) and clinical data, including measures of overall non-motor symptom severity, including fatigue, depression, anxiety, apathy, sleep problems, daytime sleepiness, and cognitive impairment. The relationship between each dietary score and symptom outcome were assessed by linear regression for continuous variables and through general linear model analysis for tertiles of dietary adherence. Results: None of the dietary indices significantly predicted the total non-motor symptom severity score. The HDI predicted a significant decrease in fatigue scores as measured by the NeuroQol fatigue item (standardised β= - .19, p= .022), after adjusting for age, gender, energy intake, years diagnosed, physical activity level, education, and smoking. Self-reported depression symptoms reduced by .17 (standardised β) for each unit increase in HDI score (p= .035), after controlling for age, gender, energy intake and years diagnosed. No other significant associations were evident between dietary scores and any other non-motor symptoms. Conclusion: Our results indicate that fatigue and depression in Parkinson’s may be modified by diet; however more research is needed using a larger sample to replicate these findings.