Body Composition In Persons With Multiple Sclerosis Vs. Healthy Controls

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Multiple Sclerosis (MS) is an autoimmune disease that attacks the myelin sheath and impedes proper conduction of action potentials through the central nervous system. As a result, persons with MS (PwMS) can experience symptoms of fatigue, muscular weakness, spasticity, and balance or gait issues. Such symptoms may reduce physical activity, negatively affecting body composition and predisposing PwMS to obesity, sarcopenia and osteoporosis. PURPOSE: The aim of the current study was to compare the body composition of PwMS and controls using DXA. METHODS: Six males and 13 females with relapsing-remitting MS and 19 Age/Sex/BMI matched healthy controls were recruited for this study. Extended disability status score (EDSS) in PwMS ranged 0 to 6 (x̄=3.1 ± 2.2). DXA scans were used to assess whole body and limb specific contents of fat, muscle and mineral content. Two-way ANOVAs (Group x Sex) with post hoc comparisons were run to assess differences across group and sex. RESULTS: Compared to male controls, MS males had a reduced whole body % lean mass (%LMWB) (60.9 ± 6.3% vs. 74.0 ± 11.0%, p=0.02), %LMARMS (66.7 ± 8.5 vs. 79.0 ± 8.6%, p=0.03), %LMLEGS (61.8 ± 6.2 vs. 75.2 ± 9.9%, p=0.02), % appendicular lean mass (aLM) (28.1 ± 5.1 vs. 35.3 ± 5.8%, p=0.03), and aLM/BMI (90.0 ± 21.10 vs. 115.8 ± 21.9, p=0.04) Similarly, the % body fat (%BF) was higher in MS males (36.7 ± 7.0%) compared to male controls (23.1 ± 11.7% and p=0.02). No between group differences were found for bone mineral content (p>0.05). When collapsed across sex, group differences disappeared in all measures except android fat mass, which was higher in PwMS (35.0 ± 16.0 kg) than controls (23.8 ± 16.3 kg, p=0.04). Interestingly, the Pearson’s r correlation between BMI and BF% was significant for the MS group (r=0.715, p<0.01) but not for the control group (r=0.347, p=0.15). EDSS scores in PwMS did not significantly correlate with any variables (p>0.05). CONCLUSIONS: Expected sex differences in body composition occurred regardless of group. MS males tended to have lower LM and higher %BF than controls, which was not seen in MS females. Significance in MS males may be explained by differences in sample size (n=6) or sex differences in MS symptom or disease progression. It is furthermore unclear to what extent individual differences in physical activity or medication may influence results.