Bone microarchitecture and bone mineral density in multiple sclerosis

Multiple sclerosis (MS) patients are at increased risk of reduced bone mineral density (BMD) and fractures. The aetiology of bone loss in MS is unclear. Trabecular bone score (TBS) is a novel analytical tool that provides a measurement of the bone microarchitecture. Decreased TBS predicts increased fracture risk independently of BMD. To date, no studies have investigated TBS in MS patients.

To assess bone quality in MS patients by TBS and to evaluate potential risk factors that may affect BMD and TBS in patients with MS.

Two hundred sixty MS patients were included. TBS was calculated using TBS iNsight software (MediMaps^® ). Multivariable regression analyses were performed with information on smoking, alcohol, glucocorticoid (GC) treatment, sun exposure, physical activity, vitamin D and BMI.

Trabecular bone score was not significantly different from an age-matched reference population. Low TBS was associated with high age (P = .014) and smoking (P = .03). Smoking and physical inactivity were associated with low BMD in spine (P = .034, P = .032). GC treatment was not associated with TBS.

We could not find altered TBS values among MS patients, suggesting that BMD alone, and not the bone microarchitecture, is affected in MS. However, larger studies are needed to verify these findings and to establish the role of TBS in MS. As in the background population, physical activity and non-smoking habits are associated with better bone health in MS.