Bone metabolism and vitamin D status in patients with multiple sclerosis

Vitamin D (VD), an important factor for bone health immobilization and immune regulation, has been shown to have low serum concentration in multiple sclerosis (MS) patients. Those patients have also multiple fracture risk factors, including progressive immobilization and long-term glucocorticoids treatment. The aim of the study was to analyze bone health (osteopenia or osteoporosis prevalence) and VD serum concentration in MS patients as well as the influence of disease activity and treatment on bone health.

The study involved 72 MS patients: 52 women and 20 men. Mean age was 40.3±10.5 yrs, mean EDSS (Expanded Disability Status Scale) 3.3±1.9. Bone health was analyzed using standard densitometry in the lumbar spine and femoral neck. Serum levels of VD, calcium, phosphate and parathormone were assessed. We compared two groups of patients with multiple sclerosis: relapsing - remitting MS (RRMS) and progressive relapsing MS (PRMS).

Densitometry revealed osteopenia in twenty-six (36.1%) patients and osteoporosis in eleven (15.3%), no bone fractures were presented. Sixty-eight MS patients (94.4%) had lower VD serum level if compared to population referential values. Thirteen patients (18.1%) had severe VD deficiency. Densitometry parameter (T-score of the lumbar spine) worsened with EDSS increase (r=-0.43, P=0.001). There was a statistically significant negative correlation between VD concentration and EDSS score (r=-0.31; P=0.009).

Our study indicates that patients with MS have high incidence of osteopenia and osteoporosis and vitamin D deficiency. Bone health disturbances studied by densitometry are related to the disability caused by MS.