Risk of osteoporotic fractures in multiple sclerosis patients in southwest Finland
Multiple sclerosis (MS) is a leading cause of non‐traumatic neurological disability in young adults. The health economic and individual burden of the chronic lifelong disease is further increased by the associated comorbidities. Patients with MS are at increased risk of fractures due to low bone mineral density (BMD) and risk of falls. Osteoporosis and osteopenia are more common than in the general population.1 Even patients with newly diagnosed MS or CIS (clinically isolated syndrome) have been shown to have lower BMD than healthy controls,5 which suggests that there are common etiological factors for both MS and osteoporosis. The effects of vitamin D on bone metabolism are well known,6 and there is also a growing body of evidence that vitamin D deficiency is a risk factor for MS.7 Smoking is another common risk factor for both MS and osteoporosis.8 MS itself further increases the risk of osteoporosis. Level of disability seems to be a major contributor to the pathogenesis of osteoporosis in patients with MS.2 Increased risk of epilepsy 12 and the consequent use of anticonvulsants decrease bone mineral density.13 The effect of high‐dose corticosteroids used during relapses on BMD in patients with MS is less clear 2 MS.
Several studies have shown that patients with MS fall frequently and over 50% of patients report at least one fall over last 3–6 months.15 Increased risk of falls in patients with MS is due to impairment in gait, balance, coordination, and cognition and in cerebellar, sensory, and pyramidal functions.15
Increased risk of osteoporotic fractures in patients with MS compared with the general population has been reported previously from Denmark, the Netherlands, and UK.22 In Finland, the prevalence of MS is high and shows relatively large regional variation,26 while recent prevalence in southwestern Finland is unknown. In our country, vitamin D deficiency is common both among patients with MS and the general population.29 A previous study from northern Finland suggested a high frequency of fractures in early stage of MS.30 The purpose of this study was to assess the prevalence of MS and the risk of osteoporotic fractures among Finnish patients with MS compared with age‐ and gender‐matched controls from a large hospital district in southwest Finland.