Low Levels of Vitamin D in Patients with Parkinson's Disease.
Parkinson's disease is a serious brain condition that results from nerve damage in certain regions of the brain that regulate the body's voluntary muscles. Also referred to as "PD," Parkinson's disease is a movement disorder that causes muscle rigidity, shaking, and slow difficult walking. PD usually strikes in mid to late adult life, although 30 percent of people with the disease experience symptoms before age 50. Another 40 percent develop the disease between ages 50 and 60. PD is a slowly progressive and incurable disease. The first sign of PD is often a slight tremor in one hand. This tremor is most visible when the individual with PD is standing or sitting still. The shaking is generally not noticeable when the hands are moving or doing something. However, tremor is absent in a small percentage of people with PD. Other classic symptoms include slow movements, "shuffling" while walking, muscle stiffness, stooped posture, and a blank facial expression. Before these symptoms begin, a person with oncoming PD may experience vague, aching pain in the limbs, neck, or back and decreased spinal flexibility. Other early and subtle symptoms include impaired handwriting ability and low speaking volume. As the disease progresses, cognitive function often suffers, and some patients develop dementia. In the later stages, people with PD often become depressed, which is certainly not difficult to understand.
Vitamin D is known as the "sunshine" vitamin because it is formed in the body by the action of the sun's ultraviolet rays on the skin. The fat-soluble vitamin is converted in the kidneys to the hormone calcitrol, which is actually the most active form of vitamin D. The effects of this hormone are targeted at the intestines and bones. Vitamin D is important for growth and development of bones and teeth in infants and children. Vitamin D has been used in the treatment of rickets, psoriasis, osteoporosis, Crohn's disease, and has been found to reduce the incidence of breast cancer and type 1 diabetes.
A new study from Emerson University School of Medicine found that a majority of patients with Parkinson's disease had insufficient levels of vitamin D. The study was designed to compare the prevalence of vitamin D deficiency in healthy controls to patients with PD. The results revealed that 55 percent of the PD patients had insufficient levels of vitamin D which was significantly higher than those with Alzheimer's disease (41 percent) or the healthy controls (36 percent). The researchers are unsure whether the low levels of vitamin D were a result of reduced sun exposure due to limited mobility or if vitamin D plays a role in the development and progression of Parkinson's disease. Further studies are being conducted to investigate whether vitamin D insufficiency is a cause or possibly a result of having PD.1
1 Evatt ML, Delong MR, Khazai N, et al. Prevalence of vitamin d insufficiency in patients with Parkinson disease and Alzheimer disease. Arch Neurol. Oct2008;65(10):1348-52.