(P18-040-24) Adherence to a Mediterranean Diet Alters Gastrointestinal Function in People With Parkinson’s Disease When Compared to Standard of Care: Data From the MEDI-PD Trial

Objectives: Parkinson’s disease is associated with gastrointestinal (GI) dysfunction including constipation symptoms, permeability, inflammation, and microbial changes that may impact disease progression. A Mediterranean diet (MediDiet) may aid in disease management, yet little is known how modifying dietary intake impacts people with Parkinsons (PwP) to improve GI dysfunction. We aimed to compare the effect of a MediDiet against standard of care on change in constipation symptoms as well as dietary intake and intestinal permeability and inflammation in PwP.

Methods: We conducted a randomized, controlled, parallel study with an 8-week intervention. PwP and symptoms of constipation who did not adhere to a Mediterranean diet were recruited and randomized to receive education on standard of care for constipation (Control; n=17, 65.1±2.2 y) or standard of care + MediDiet (n=19, 68.8±1.4 y). The primary outcome was to compare change in constipation symptoms between groups using the Gastrointestinal Symptom Rating Scale (GSRS) in which 1=no discomfort to 7=very severe discomfort. Secondary outcomes included bowel habits, laxative usage, dietary intake and fecal zonulin and calprotectin.

Results: Changes from baseline (week 0) to final (week 8) for GSRS constipation syndrome scores were not different between groups (MediDiet, -0.53±0.18; Control, -0.58±0.21; P=0.60), but only the MediDiet reported decreased constipation scores at weeks 4 and 8 when compared to baseline (P=0.041 and P=0.039, respectively). The MediDiet group had higher intake of dietary fiber during the intervention (P < 0.001) and used less laxatives than controls (P=0.04). No differences in fecal zonulin were observed between groups (P=0.33) but fecal calprotectin tended to be lower in the MediDiet group (P=0.05).

Conclusions: The MediDiet is associated with improved constipation symptoms in PwP likely due to promotion of high-fiber foods and may provide other benefits such as reduced laxative usage. Future work is needed to explore associated mechanisms of MediDiet on improving non-motor symptoms and the gut-brain axis in PwP.

Funding Sources: Lauren and Lee Fixel Family Foundation, The John McCallan Family fund, and the USDA National Institute of Food and Agriculture Hatch Project