The risk of fracture in incident multiple sclerosis patients: the Danish National Health Registers.

BACKGROUND

Patients with multiple sclerosis (MS) may be at increased risk of fractures owing to osteoporosis and falling.

OBJECTIVE

To evaluate the risk of fracture in incident MS patients drawn from a dedicated MS registry compared with population-based controls.

METHODS

We conducted a population-based cohort study (1996-2007) utilising the Danish National Health Registers that were linked to the Danish MS Registry and the Danish MS Treatment Registry. Incident MS patients (2963 cases) were 1:6 matched by year of birth, gender, calendar time and region to persons without MS (controls). Cox proportional hazards models and logistic regression were used to estimate the risk of fracture in MS. Time-dependent adjustments were made for age, history of diseases and drug use.

RESULTS

Compared with controls, patients with MS had no overall increased risk of fracture (adjusted hazard ratio (adj. HR): 1.0, 95% CI: 0.9-1.2). However, the risk of femur/hip fracture (adj. HR: 1.9, 95% CI: 1.1-3.4) was significantly increased compared to controls. As compared with unexposed patients, MS patients who had been exposed to a short course of methylprednisolone in the prior year had no significantly increased risk of osteoporotic fracture (adj. HR: 1.2, 95% CI: 0.5-2.9). Disabled MS patients with Expanded Disability Status Scale [EDSS] scores between 6 and 10, had a 2.6-fold increased risk of osteoporotic fracture (adjusted odds ratio (adj. OR): 2.6, 95% CI: 1.0-6.6) compared to patients with an EDSS score between 0 and 3.

CONCLUSION

Patients with MS had a higher risk of femur/hip fracture than controls. Disability status is probably more important than glucocorticoid use in the aetiology of MS and osteoporotic fracture.