Written by Marcia J. Egles, MD. Parkinson’s disease patients given 1200 IU vitamin D per day showed 17% less neurological deterioration than non supplemented patients.

A recent clinical trial from Japan demonstrates that vitamin D supplementation may be especially beneficial to patients with Parkinson’s disease (1). Parkinson’s  disease is a movement disorder which affects  nerve cells in the brain. The symptoms of Parkinson’s disease include tremors, muscle rigidity, and problems with walking, speech and cognition. Parkinson’s disease symptoms are chronic and become progressively worse over time. Drugs such as Levophed (l-dopamine) have been valuable in controlling the symptoms, but the disease is not reversible or curable (2).

The study’s researchers had published a previous study (3) identifying one genetic group of Parkinson’s disease patients who experience a milder form of the disease. These persons possess a gene called FokI CC  which codes for the vitamin D receptor VDR. The VDR is found throughout the body and is particularly expressed  within part of the brain affected by Parkinson’s disease. In this previous study, both higher serum 25-hydroxyvitamin D level and the FokI CC genotype were associated with milder Parkinson’s disease.

The new study, a small, randomized and controlled clinical trial, examined the effect of Vitamin D supplementation on persons with Parkinson’s disease. For a twelve month trial, 114 Parkinson disease patients, ages 45-85 years, were randomly assigned to daily take either a placebo or 1200 IU of vitamin D3. Only patients who were not previously receiving vitamin D supplements were allowed into the study. At baseline in both groups, 48% were considered vitamin D deficient ( less than 20 ng 25(OH)D/ml) and 22% vitamin D sufficient ( greater than 30 ng 25(OH)D/ml). The populations of VDR genetic varieties were similar between the two groups.

At baseline, the two groups had similar overall characteristics. Both groups had persons with similar burden of disease requiring similar degrees of medications. During and after the 12 months of vitamin D supplementation, the patients were monitored for changes in their levels of function. After the 12 months,those who took the vitamin D supplements had serum 25 (OH)D concentrations in the normal range (41.7 +/- 12.6 ng/ml after 12 months )  whereas vitamin D levels remained unchanged (21.4 ng/ml) and insufficient in the placebo group.

Compared with placebo, vitamin D3 significantly prevented deterioration of neurological state as measured by the Hoehn and Yahr staging system (HY) and by the United Parkinson’s Disease Rating Scale (UPDRS).

Sixteen of 55 patients (29%) in the vitamin D treatment group had no neurological deterioration on the HY scale compared with 7 of 57 (12.3%) patients in the control group. In the activities of daily living part of the UPDRS, 59 % of the treatment group did not worsen compared with 38% of the placebo group ( P= 0.03). No adverse effects of vitamin D supplementation were observed.

The researchers noted that other studies done in older adults have documented improvements in muscle strength and balance with vitamin D supplementation (4). Thus it cannot be distinguished whether vitamin D might delay the progression of Parkinson’s disease or whether it nonspecifically improves strength and balance.

When the data was considered in view of the patients’ vitamin D receptor (VDR) genotype classification, those with  the aforementioned FokI CC (34% of the patients), showed no benefit with vitamin D supplementation. The patients who demonstrated the stabilization of symptoms were patients with FokI TT or FoKI CT  genotypes (66% of the patients).

An editorial published in the same journal as the Japanese study, emphasized the importance of this study to Parkinson’s disease patients. It noted that this study’s results strongly suggest that low vitamin D status accelerates Parkinson’s disease progression. The Japanese study is the first of its type and needs another study to confirm the findings. The editorial noted that ,” Even if optimal vitamin D status delays Parkinson’s disease progression by a small degree, this treatment is cheap, simple to access ( eg, across the counter), relatively safe, and publicly acceptable.” (5).

Source: Suzuki, Masahiko, et al. “Randomized, double-blind, placebo-controlled trial of vitamin D supplementation in Parkinson disease.” The American journal of clinical nutrition 97.5 (2013): 1004-1013.

© 2013 American Society for Nutrition

Posted December 6, 2013.

Marcia Egles, MD, graduated from Vanderbilt University School of Medicine in 1986. She completed her residency in Internal Medicine at St. Louis University Hospital. Dr. Egles is certified in Internal Medicine and is a member of the American College of Physicians. She resides in Avon, IN with her husband and two sons.

References:

  1. Suzuki, M et al. Randomized, double-blind, placebo-controlled trial of vitamin D supplementation in Parkinson disease.  Am J Clin Nutr 2013; 97:1004-13.
  2. James, Lucy Elizabeth and Ayodeji A. Asuni ,  Parkinson’s Disease and the “Sunshine Vitamin”. J Alzheimers Dis Parkinsonism vol. 3, issue 2, 1000120.  2013.  ( An ‘open access ‘ review article.)
  3. Suzuki M, et al.  25-hydroxyvitamin D, vitamin D receptor gene polymorphisms, and severity of PD.  Mov Disord 2012: 27: 264-71.
  4. Muir SW, et al.  Effect of vitamin D supplementation on muscle strength, gait and balance in older adults; a systematic review and meta-analysis.  J Am Ger Soc 2011: 59: 2291-300.
  5. Xiaoying Cui, et al Low vitamin D concentration exacerbates adult brain dysfunction. Mov Disord 2012: 27.