The Relationship Among Bone Mineral Density, Bone Biomarkers and Vitamin D Levels in Patients with Parkinson's Disease.

BACKGROUND

Idiopathic Parkinson's disease (IPD) is the most common age-related neurodegenerative movement disorder. It causes a decrease and deceleration in movements. It may also lead to loss of bone mineral density, vi-tamin D deficiency, falls and fractures due to various factors. As indicated in our study, determining the prevalence of osteopenia and osteoporosis in IPD is important to determine complications.

METHODS

Thirty patients with IPD and 30 age-matched control subjects were included in the study. The bone mineral density (BMD) measurements of the participants were taken from the lumbar spine (L1-4) and double femur regions using the dual energy X-ray absorptiometry device. Serum 25 (OH) vitamin D, alkaline phosphatase, parathormone, osteocalcin, prolidase and urine hydroxyproline levels were measured.

RESULTS

The femur total BMD and serum 25 (OH) vitamin D levels were lower in the patients with IPD than in the control group (p > 0.05). The serum prolidase and urinary hydroxyproline levels were higher in the IPD group relative to the control group (p < 0.05). The frequency of osteoporosis and osteopenia was significantly higher in the IPD group than in the control group (p < 0.05).

CONCLUSIONS

Patients with Parkinson's disease tend to have lower vitamin D levels than those with a similar age without Parkinson's disease. Vitamin D levels are usually associated with BMD in people with Parkinson's disease, but administering vitamin D does not improve BMD. Cross-sectional studies suggest a correlation between vitamin D levels and the severity of symptoms of Parkinson's disease. Decreased exposure to sunlight due to immobilisation and reduced vitamin D intake by diet may lead to vitamin D deficiency and low BMD. There is a negative correlation among the duration of disease, disease severity, number of falls, parathormone level and serum vitamin D level in people with Parkinson's disease. Consequently, vitamin D levels may be low in Parkinson's disease patients. Therefore, patients with Parkinson's disease should be checked for vitamin D and osteoporosis by considering the risk of hip fracture, fall from a height and high risk of osteoporosis.