A simple score for estimating the long-term risk of fracture in patients with multiple sclerosis

OBJECTIVE: To derive a simple score for estimating the long-term risk of osteoporotic and hip fracture in individual patients with MS.

METHODS: Using the UK General Practice Research Database linked to the National Hospital Registry (1997-2008), we identified patients with incident MS (n = 5,494). They were matched 1:6 by year of birth, sex, and practice with patients without MS (control subjects). Cox proportional hazards models were used to calculate the long-term risk of osteoporotic and hip fracture. We fitted the regression model with general and specific risk factors, and the final Cox model was converted into integer risk scores.

RESULTS: In comparison with the FRAX calculator, our risk score contains several new risk factors that have been linked with fracture, which include MS, use of antidepressants, use of anticonvulsants, history of falling, and history of fatigue. We estimated the 5- and 10-year risks of osteoporotic and hip fracture in relation to the risk score. The C-statistic was moderate (0.67) for the prediction of osteoporotic fracture and excellent (0.89) for the prediction of hip fracture.

CONCLUSION: This is the first clinical risk score for fracture risk estimation involving MS as a risk factor.