Low serum Vitamin D levels may contribute to gastric dysmotility in de novo Parkinson's disease

Background and Objectives: Gastrointestinal dysfunction is a common non motor symptom in Parkinson's disease (PD). However, the potential association between vitamin D and gastroparesis in PD has not been previously investigated. The aim of this study was to compare vitamin D levels between drug-naive de novo PD patients with normal gastric emptying and those with delayed gastric emptying. Methods: Fifty-one patients with drug-naive de novo PD and 20 age-matched healthy controls were enrolled in this study. Gastric emptying time (GET) was assessed by scintigraphy, and gastric emptying half-time (T_1/2) was determined. The PD patients were divided into a delayed-GET group and a normal-GET group. Results: The serum 25-hydroxyvitamin D₃ levels were decreased in the delayed-GET group compared with the normal-GET and control groups (11.59 ± 4.90 vs. 19.43 ± 6.91 and 32.69 ± 4.93, respectively, p < 0.01). In the multivariate model, the serum 25-hydroxyvitamin D₃ level was independently associated with delayed gastric emptying in PD patients. Conclusions: Vitamin D status may be an independent factor for gastric dysmotility in PD. Although the underlying mechanism remains to be characterized, vitamin D status may play a role in the pathogenesis of delayed gastric emptying in drug-naive PD.