Vitamin D deficiency is more common in individuals with Parkinson’s disease than in healthy adults of the same age or in patients with Alzheimer’s disease, says a study published in the October issue of Archives of Neurology.
Researcher Marian L. Evatt, M.D., M.S. (Emory University School of Medicine, Atlanta) and colleagues write that, “Vitamin D is important for maintaining many physiologic functions, and vitamin D deficiency is associated with increased risk of disease.” Further, risk factors for vitamin D insufficiency – such as advancing age, obesity, avoidance of sun exposure, residence in northerly latitudes, and darker skin – are commonly observed in patients with chronic neurodegenerative diseases like Parkinson’s and Alzheimer’s diseases.
To investigate the relationship between vitamin D levels and neurodegenerative diseases, Evatt and colleagues studied 100 patients with Parkinson’s disease, 97 Alzheimer’s disease patients, and 99 healthy individuals. Participants were matched for age, sex, race, genotype and geographic location.
The researchers found that, “Significantly more patients with Parkinson’s disease (55 percent) had insufficient vitamin D than did controls (36 percent) or patients with Alzheimer’s disease (41 percent).” Parkinson’s disease patients had an average of 31.9 nanograms per milliliter vitamin D concentration, and Alzheimer’s disease patients and healthy group individuals had concentrations of 34.8 and 37 nanograms per milliliter, respectively – significantly high concentrations of vitamin D than the Parkinson’s patients.
“These findings support the previously suggested need for further studies to assess what contribution a low 25(OH)D [a measure of blood vitamin D levels] concentration adds to the risk of developing Parkinson’s disease (vs. other neurodegenerative disorders) and to determine whether correction of vitamin D insufficiency and deficiency will improve motor or non-motor symptoms in Parkinson’s disease,” conclude Evatt and colleagues.
They add: “Finally, the finding of a high incidence of vitamin D deficiency in the Parkinson’s disease and other cohorts highlights the importance of routinely checking the level of 25(OH)D, particularly in elderly patients, since deficiency is strongly correlated with a higher incidence of osteoporosis, falls and hip fractures and has been associated with a higher incidence of several forms of cancer and autoimmune disorders.”
Prevalence of Vitamin D Insufficiency in Patients With Parkinson Disease and Alzheimer Disease
Marian L. Evatt; Mahlon R. DeLong; Natasha Khazai; Ami Rosen; Shirley Triche; Vin Tangpricha
Archives of Neurology(2008). 65(10):1348-1352.
Written by: Peter M Crosta