Prevalence of Vitamin D Insufficiency in Patients With Parkinson Disease and Alzheimer Disease

Top Cited Papers
Open Access
Publisher Website
Google Scholar
Abstract
Vitamin D is important for maintaining many physiologic functions, and vitamin D deficiency is associated with increased risk of disease. Optimal balance, muscle strength, and innate immunity1-3 require adequate vitamin D levels; vitamin D deficiency is associated with increased risk for several types of cancer, as well as autoimmune and cardiovascular disorders.1,3-7 Vitamin D also regulates processes known to go awry in multiple sclerosis, Parkinson disease (PD), and other neurodegenerative disorders, including neurotrophin, inducible nitric oxide synthase, glutathione and monoamine synthesis, and apoptosis.8,9 The enzyme 25-hydroxyvitamin D-1α-hydroxylase (1α-OHase) converts the storage 25-hydroxyvitamin D (25[OH]D) form to the biologically active vitamin D form, 1,25-dihydroxyvitamin D. Both 1α-OHase and vitamin D receptors (VDRs) are expressed in many extrarenal tissues, including muscle and brain. Given the high prevalence rates of vitamin D deficiency in such varied populations as elderly patients, chronically ill patients, and healthy young adults1 and the widespread distribution of the VDRs and 1α-OHase in brain and muscle,10,11 optimal vitamin D status may be important for preventing or treating neurodegenerative disorders.