The purposes of the present study were to evaluate bone mineral density (BMD) and vitamin D status in Parkinson's disease (PD) and to identify the correlation of vitamin D with BMD and disease related parameters.

Fifty-two patients with PD and 39 controls were recruited in study. Hoehn and Yahr (HY) staging scale, parts II and III of the Unified Parkinson's Disease Rating Scale (UPDRS) were used to assess disease stage, daily living activities, and motor activity, respectively. BMD of lumbar spine and femoral neck were assessed by dual energy X-ray absorptiometry. Serum 25-hydroxyvitamin D (25OHD) levels were measured.

Seventeen patients (32.7%) were osteoporotic and 22 (42.3%) osteopenic. Female and male PD patients had significantly lower T scores and BMD values at femoral neck, whereas only female patients showed significant differences in T scores and BMD values at lumbar spine compared to controls. The mean 25OHD levels were significantly lower in PD patients compared with controls. 25OHD levels showed a positive correlation with T scores and BMD values of lumbar spine and femoral neck and a negative correlation with UPDRS part II, UPDRS part III, and HY stage. In partial correlation analysis performed to adjust disease duration, 25OHD levels were also correlated with lumbar and femoral neck BMD values, femoral neck T scores, but not with other studied parameters.

This study demonstrated that PD patients had lower 25OHD levels and decreased BMD values compared to controls and detected significant association of 25OHD levels with BMD values.