Testosterone Replacement Therapy in Chronic Spinal Cord Injury

This study is 24 months in duration. Men who have consented to pre-screening serum testosterone draw and are found to have total testosterone levels averaging ≤ 11.3 nmol/l will start testosterone replacement therapy after a 6-month baseline period. Once treatment begins subjects will place a testosterone replacement patch (5 or 10 mg/day) on various sites of the body daily. Subjects will visit the lab after 2,6, 12, and 18 months of therapy for testing; however they will stop taking the patch at the 12 month visit. If needed, a steroid cream will be provided to the subjects should any skin irritations occur. If the patch causes persistent skin irritations, despite use of the steroid cream, then a testosterone gel may be used. Detailed instructions and precautions using the gel are outlined in the consent form and will be reviewed with the subject. Those men who have consented to pre-screening serum testosterone and are found to have normal levels of total testosterone (testosterone total ≥ 11.4 nmol/l) are eligible to participate as a control subject for the full 24-month period of the study. These subjects visit the lab at baseline (BL), 12 and 24 months for the same testing as those in the treatment group.