OBJECTIVE

To study a role of vitamin D and other indicators of calcium-phosphorus metabolism as possible predictors of Parkinson’s disease (PD).

MATERIAL AND METHODS

The main group consisted of 138 patients with PD, the control group included 79 patients without PD. Serum levels of 25-hydroxyvitamin D (25[OH]D) were determined by chemo-luminescence immunoassay. Additionally, the following biochemical markers were evaluated: parathyroid hormone, calcitonin, thyroid-stimulating hormone, thyroxine, alkaline phosphatase, inorganic phosphorus, total calcium, ionized calcium, total protein. In addition, densitometry of the spine (1—4 lumbar vertebrae), proximal femurs, and the middle third of the radius was performed. The relationship between the level of vitamin D in blood serum and clinical data was evaluated using correlation analysis.

RESULTS

Regression analysis revealed a statistically significant contribution of the levels of parathyroid hormone, vitamin D, alkaline phosphatase and the T-value of the bone density of the neck of the right hip (T-score NRH) to the probability of PD. In the main group, bone mineral density was significantly different between the groups (p=0.028). Also, there was a high incidence of osteopenia (64%) and osteoporosis (73%). Based on the obtained regression equation, the probability of having PD is p=1/(1+exp^{2.673–0.007x–0.052y–0.037z–0.012k}), where «x» is the parathyroid hormone level, «y» is T-score NRH, «z» is the vitamin D level, «k» is the activity of alkaline phosphatase, exp is the exponent.

CONCLUSION

Vitamin D levels, alkaline phosphatase activity, and T-score NRH have a statistically significant effect on the likelihood of developing PD. With a decrease in the above indicators relative to normal values, the likelihood of having PD increases.