Men with multiple sclerosis may experience improvements in cognitive function and a slowing of brain atrophy with testosterone therapy, according to research that will be presented at the American Academy of Neurology 58th Annual Meeting in San Diego, Calif., April 1 -  8, 2006.

While men are less susceptible to many autoimmune diseases, including MS, the reason is not known. In men, the age at onset of MS is generally later than in women, and coincides with a decline in testosterone levels. Testosterone may serve to protect the nerve cells that are damaged by the autoimmune attack on myelin that occurs in MS and maintaining cognitive function (the ability to think, reason, concentrate or remember).

Researchers from the University of California at Los Angeles recently conducted the first study of testosterone treatment in men with relapsing-remitting MS. Relapsing-remitting MS (RRMS) is characterized by relapses during which time new symptoms can appear and old ones resurface or worsen, followed by periods of remission, during which time the person fully or partially recovers from the relapse.

The 10 patients in the pilot study received daily treatment with 100 mg of testosterone gel applied to the skin for a period of one year. None of the men was currently taking immunomodulating drugs (drugs that control the immune system) for MS. Clinical assessments including cognitive measures and blood tests were obtained every three months, and magnetic resonance images were reviewed monthly.

Compared to the pretreatment period, significant improvements in performance on the Paced Auditory Serial Addition Task (PASAT) were detectable after 12 months of treatment with testosterone. The PASAT is a test of processing speed and working memory function. While the improvements were small with testosterone treatment (about four percent), in previous studies of other MS treatments PASAT performance continued to worsen with treatment, although at a slower rate. In addition, with testosterone treatment, there were trends for improvements in tests of spatial memory as well.

Blood tests demonstrated that the production of a growth factor (brain-derived neurotrophic factor) that helps promote nerve cell survival increased more than two-fold after testosterone supplementation. Also, the rate of brain atrophy slowed by 67 percent during the last nine months of testosterone treatment.

“We found that the testosterone treatment resulted in significant improvements in cognitive function, increases in neurotrophic factor production and a slowing of brain atrophy,” said study author Nancy Sicotte, MD, of the David Geffen School of Medicine at UCLA. “There was no change in the number or size of MS-related lesions as measured by MRI, although lesion activity was low in the group overall. Our study results in this small group of patients suggest that testosterone therapy may have neuroprotective effects in RRMS, but further study using a placebo-controlled, blinded design in larger groups of men with RRMS is needed to confirm these preliminary results.”

The study was supported by the National Multiple Sclerosis Society.

The American Academy of Neurology, an association of more than 19,000 neurologists and neuroscience professionals, is dedicated to improving patient care through education and research. A neurologist is a doctor with specialized training in diagnosing, treating and managing disorders of the brain and nervous system such as Alzheimer disease, epilepsy, multiple sclerosis, Parkinson disease, and stroke.

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