Low-dose niacin uptake over 12 months was associated with improvements in the UPDRS III motor score, as well as fatigue and mood in people with Parkinson disease.
As study authors explain, previous research has indicated that people with PD present with lower vitamin B3 levels compared with controls. “It may be related to carbidopa interaction, defective tryptophan metabolism, and stresses of night sleep disorder,” they added.
With vitamin B3 serving as the energy source for all cells by producing 2 compounds involved in metabolic actions throughout the body, called nicotinamide adenine dinucleotide (NAD+) and nicotinamide adenine dinucleotide phosphate (NADP+), some symptoms of PD were noted to be potentially exacerbated by its deficiency, including fatigue, sleep dysfunction, and mood changes.
Amid growing evidence suggesting that patients with PD require vitamin B3 supplementation, as opposed to solely consuming B3-rich food, researchers conducted a 12-month effectiveness trial to assess the effect of low-dose over-the-counter niacin enhancement, a B3 derivative, in patients with PD on symptom and biochemical outcomes.
To ensure that there were no adverse reactions, patients with idiopathic PD (N = 47; men, n = 32; mean [SD] age, 62  years) initially underwent 3-month double-blinded run-in dose-dependent supplementation, in which participants were randomized to placebo (n = 16) or once-daily slow-release niacin of 100mg (n = 15) or 250mg (n = 15).
Among the 46 patients who completed the 3-month test, those of the placebo and 100mg groups switched to the fixed-dose 250-mg slow-release regimen for 12 months, with participants who were already taking the 250mg dosage continuing to do so for 9 months to achieve the same 12 month effect of the other groups.
Participants were assessed for the primary outcome of the Unified Parkinson’s Disease Rating Scale (UPDRS) III (motor) score, with secondary outcomes of cognitive functioning and postural stability also examined.
Of the 46 patients assessed over 12 months, 42 completed the trial. In their findings, a decreased average (SD) score of 3.5 (6) points was observed after 12 months of daily niacin, indicating an improvement from 21.5 (12.9) to 17.7 (11.7) points (P = .0009).
Furthermore, several secondary outcome measures improved across the 12-month period:
Conversely, set shifting, as measured by the Trail Making-B test, worsened from 66 seconds to 96 seconds. Quality of night sleep also remained the same, although there was a trend observed in the decrease of awakening episode frequency, which researchers said is not clear whether it is a positive benefit of the vitamin.
“These results suggest that niacin enhancement has the potential to maintain or improve quality of life in PD and slow disease progression,” concluded the study authors.
Chong R, Wakade C, Seamon M, Giri B, Morgan J, Purohit S. Niacin enhancement for Parkinson’s disease: an effectiveness trial. Front Aging Neurosci. Published online June 17, 2021. doi:10.3389/fnagi.2021.667032