Testosterone plus PDE-5 inhibitor improves ED in elderly men9/9/2005In healthy aging men with erectile dysfunction (ED), low dose testosterone therapy added to low-dose phosphodiesterase 5 (PDE-5) inhibitor therapy significantly improves erectile function and quality of life, according to research presented this week at ENDO 2005, the 87th annual meeting of The Endocrine Society. "Healthy aging men may develop erectile dysfunction and they are usually put on an oral PDE-5 inhibitor and they usually respond for a short period of time, but after that there often is total failure with no response at all," Dr Fredrick M. Ellyin explained.
"We believe this is the first study looking at this combination (of testosterone and PDE-5 inhibition) in aging healthy men with ED," the researcher from The Chicago Medical School in North Chicago, Illinois said. Dr Ellyin's team studied the clinical and biochemical effects of low-dose testosterone combined with low-dose PDE-5 inhibitor therapy in 12 otherwise healthy 65- to 85-year-old men with ED.
"The beauty of our study is that we gave 5 or 10 mg PDE-5 inhibitor instead of 25 or 50 milligrams as is usual," he explained. "For testosterone, we gave 25 milligrams every week or 50 milligrams every two weeks instead of 150 milligrams every two weeks, which is the therapeutic dose. With this novel regimen, more than 90% of men reported significant improvement in erectile function and this improvement lasted for more than two years," Dr Ellyin said. "These days," he added, "PDE-5 inhibitors are under a lot of scrutiny for side effects but in our study in two years we didn't see any side effects, probably because we are using such small doses."
Testosterone levels increased "mildly but significantly," the authors noted. There was no change in prostate size or prostate specific antigen (PSA) level. Total cholesterol and low-density lipoprotein cholesterol (LDL-C) fell significantly and there was no change in high-density lipoprotein cholesterol (HDL-C) or triglycerides.
This study confirms previous studies that low dose testosterone is a "relatively safe therapy as far as atherogenicity is concerned," the investigators note. Dr Ellyin plans to follow these patients for another full year to determine long-term efficacy and safety of this regimen and hopes to report three-year data next year at ENDO 2006.
