Lowering of testosterone levels, by medications or surgery (Androgen Deprivation Therapy or ADT), is commonly used in the treatment of prostate cancer. The adverse effects of low testosterone include decreased sex drive, impotence, decreased lean body mass and muscle strength, increased fat mass, decreased quality of life and osteoporosis.~An increase in body fat and decrease in lean body mass may contribute to a decrease in the body's ability to use insulin effectively, leading to insulin resistance and diabetes. Low testosterone levels are also associated with elevated total cholesterol, LDL-cholesterol and triglycerides.~Two groups of non-diabetic men will be studied:~Men with known history of prostate cancer who were treated with surgery and/or radiation therapy and are now in remission and not receiving androgen deprivation therapy (non-ADT group).~Men with newly diagnosed or known history of prostate cancer who are being advised by their physicians to begin androgen deprivation therapy (ADT group).~The non-ADT group and half of the ADT group will be observed for the development of insulin resistance/diabetes. The other half of the ADT group will receive a diabetes medication called Pioglitazone (Actos) to evaluate any beneficial effects of this medication in the prevention of metabolic dysfunction.~The study will consist of a screening visit and 6 additional study visits throughout one year. Procedures during this study include blood draws, MRI, CT, DEXA scan, insulin clamp procedures, oral glucose tolerance tests, carotid IMT, pulse wave velocity, neuropsychological testing, physical exams and an optional muscle biopsy.
The purpose of this study is to examine the link between low testosterone and insulin resistance/diabetes in men undergoing androgen deprivation therapy for prostate cancer. The study will also evaluate other cardiovascular risk factors in these men.