OBJECTIVES: Testosterone therapy for the treatment of hypogonadism in older men is controversial.  Previous studies on benefits have been inconclusive and there is the belief that the known potential for negative cardiac outcomes outweighs any benefit.  We used a sample of Medicare patients to test the time from diagnosis of hypogonadism to positive and negative events related to treating hypogonadism METHODS: Using a 5% random sample of Medicare LDS claims from 2011-2013 we selected a cohort of men diagnosed with hypogonadism who had no evidence of hypogonadism in a six month pre period.  These men were divided into those who received injectable testosterone therapy (case-T) and those who did not (control-NT).  For analysis three controls were selected for each case using Greedy matching on age, race, Charleson comorbidity index (CCI), presence of hypercholesteremia and hypertension.  Each cohort was followed for two years identifying outcomes including: gynecomastia, abnormal weight gain, stroke, myocardial infarction (MI), osteopenia, and osteoporosis.  Median time to event was calculated for each group.  Kaplan-Meyer curves with Wilcoxon tests were used to compare time to event for each disease. RESULTS: