Markers of bone remodeling predict rate of bone loss in multiple sclerosis patients treated with low dose glucocorticoids

BACKGROUND: The aim of this study was to evaluate the clinical value of markers of bone remodeling in assessment of rate of bone loss in patients with multiple sclerosis (MS) long term treated with low dose glucocorticoids. METHODS: The study involved 70 patients with MS. Motor function of the patients was evaluated using the Kurtzke Expanded Disability Status Scale (KEDSS). Bone mineral density (BMD) was determined at the lumbar spine and proximal femur at baseline and after 1.8 +/- 0.8 years. Bone remodeling was assessed using circulating concentrations of type 1 collagen cross-linked C-telopeptide (beta CTX), aminoterminal propeptide of type I procollagen, and N-MID osteocalcin (OC). A control group of 140 age-matched healthy subjects was used to compare bone-turnover markers. RESULTS: The plasma CTX concentration was the most significant parameter of bone remodeling which correlated with the rate of bone loss and with the KEDSS. The rate of bone loss at the proximal femur was not significantly different between tertiles of plasma OC concentrations. CONCLUSION: In physically active patients with MS treated with low-dose GC, the bone-turnover markers were not different from controls. Patients having plasma CTX but markers of bone formation higher as compared to controls were confirmed 2 years later as bone losers.