Abstract
BackgroundParkinson’s Disease (PD) patients have lower niacin levels compared to their spouses. The main objective was to study low-dose daily niacin supplementation versus placebo on motor symptoms in Parkinson’s disease subjects.MethodsA randomized, placebo-controlled, double-blind, single-center clinical trial in Parkinson’s disease patients was performed in Augusta, GA, between September 2016 to September 2019. Randomized participants were 47 PD patients who received either low-dose niacin (N = 21 ) or placebo (N = 26) for the first six months (mean age 68.4 SD, 8.7; mean duration of disease 5.8 SD 4.9; H&Y scores between 0.5 to 4; 64% subjects were Veterans). The Veterans Affairs Pharmacy generated the randomized sequence. After the double-blind phase, all participants received open-label niacin for the next six months. All patients were evaluated at baseline, six months, and one year of treatment. The main outcome measure was the Unified Parkinson’s Disease Rating Scale III (UPDRS III) scores. Secondary outcome measures were depression, sleep quality, mental flexibility and cognition, and physical fatigue.Results39 subjects were analyzed with low-dose niacin (N = 18) and placebo (N = 21) for the completion of the first six months (randomized, double-blind), and 31 subjects were analyzed for the completion of the next six months (open-label) with low-dose niacin (N = 14) and placebo (N = 17). Niacin treatment was not tolerated by two subjects. The baseline mean UPDRS III score was 21.3 ± 15.8 for the niacin group and 22.4 ± 11.8 for placebo. The change with six months of placebo was 0.05 [95% CI, -2.4 to 2.32], and niacin was 1.06 [95% CI, -3.68 to 1.57]. From six to twelve months, the average UPDRS III score decreased for the placebo group by 4.58 [95% CI, -0.85 to 8.30] and the niacin group by 4.63 [95% CI, 1.42 to 7.83]. Eight subjects withdrew from the study before the 6-month time point and eight more before the one-year time point due to voluntary discontinuation, flushing, or inability to continue (SARS-CoV-2 shut-down).ConclusionLow-dose niacin supplementation may be helpful as an adjunct therapy in improving motor function in PD.Trial registrationClinicaltrials.gov, NCT03462680. Registered 12 March 2018- Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT03462680?term=gpr109A&draw=2&rank=1