Effects of 3-Month Vitamin D₃ Supplementation on Motor and Non-Motor Symptoms in Parkinson's Disease: A Single-Arm...

To evaluate the effects of three months of vitamin D₃ supplementation on vitamin D status, motor function, sleep quality, and depressive symptoms in patients with Parkinson's disease and vitamin D insufficiency.

In this open-label, single-arm pre - post interventional study, 49 patients with Parkinson's disease received oral vitamin D₃ supplementation (7500 IU/day) for three months. Serum 25(OH)D levels and clinical outcomes were assessed at baseline and post-intervention using the Unified Parkinson's Disease Rating Scale (UPDRS), Hoehn and Yahr stage, Pittsburgh Sleep Quality Index (PSQI), and Beck Depression Inventory (BDI).

Mean serum 25(OH)D levels increased significantly from 15.91 to 26.45 ng/mL (p < .001). UPDRS total and parts I - III scores improved significantly, while part IV showed no change. PSQI and BDI scores also decreased significantly. However, changes in 25(OH)D levels were not correlated with clinical outcomes, and subgroup analyses showed no differences according to post-intervention vitamin D status.

Vitamin D₃ supplementation improved biochemical and clinical measures in patients with Parkinson's disease and vitamin D insufficiency. However, the increase in vitamin D levels was not associated with clinical changes.

Assessment and correction of vitamin D insufficiency may be considered in Parkinson's disease, but potential clinical benefits should be interpreted cautiously until confirmed by randomized controlled trials.