Testosterone Treatment in Multiple Sclerosis: a Pilot Study

Objective: To study the effect of testosterone supplementation on men with multiple sclerosis (MS).

Design, Setting, And Participants: Men are less susceptible to many autoimmune diseases, including MS. Possible causes for this include sex hormones and/or sex chromosome effects. Testosterone treatment ameliorates experimental allergic encephalomyelitis, an animal model of MS, but the effect of testosterone supplementation on men with MS is not known. Therefore, 10 men with relapsing-remitting MS were studied using a crossover design whereby each patient served as his own control. There was a 6-month pretreatment period followed by a 12-month period of daily treatment with 10 g of the gel containing 100 mg of testosterone.

Main Outcome Measures: Clinical measures of disability and cognition (the Multiple Sclerosis Functional Composite and the 7/24 Spatial Recall Test) and monthly magnetic resonance imaging measures of enhancing lesion activity and whole brain volumes.

Results: One year of treatment with testosterone gel was associated with improvement in cognitive performance (P = .008) and a slowing of brain atrophy (P <.001). There was no significant effect of testosterone treatment on gadolinium-enhancing lesion numbers (P = .31) or volumes (P = .94). Lean body mass (muscle mass) was increased (P = .02).

Conclusion: These exploratory findings suggest that testosterone treatment is safe and well tolerated and has potential neuroprotective effects in men with relapsing-remitting MS.