• Improvements in bone quality, muscle strength, cardiac function, cognition, sexual and overall well-being [ Time Frame: 1 year ] [ Designated as safety issue: No ]
• Urinary symptoms [ Time Frame: 1 year ] [ Designated as safety issue: Yes ]
• Glucose tolerance [ Time Frame: 1 year ] [ Designated as safety issue: No ]
• Blood lab values [ Time Frame: 1 year ] [ Designated as safety issue: Yes ]

• Improvements in bone quality, muscle strength, cardiac function, cognition, sexual and overall well-being
• Urinary symptoms
• Glucose tolerance
• Blood lab values

The purpose of this study is to determine if an aromatase inhibitor (a drug that inhibits the conversion of testosterone to estrogen) is as effective as testosterone replacement in improving muscle mass, muscle strength, sexual function, memory, and bone health.

Approximately 20% of men over the age of 70 have low testosterone levels. In some studies, testosterone replacement has resulted in improvement in bone mass, muscle strength, quality of life and memory function. In the body, testosterone is converted into estrogen. Hence, it is unclear whether these beneficial effects are due to testosterone or estrogen. Research has shown that inhibition of estrogen production in men results in an increase in testosterone levels.

In this study, patients will be assigned to one of three groups: one group will receive testosterone gel and a placebo tablet, one group will receive a 1mg Anastrozole tablet and a placebo gel, and one group will receive a placebo tablet and placebo gel. Each group will receive a daily dose of calcium with vitamin D. The study requires 6 visits over a 12-month period for testing and evaluation. Two of the 6 visits will require an overnight stay in the hospital so that an intravenous (IV) line can be placed in the arm to allow samples to be drawn throughout the night. Testing will include a cardiac stress test, a glucose tolerance test, bone and muscle tests, evaluation of memory function, etc. For the safety of the prostate, we will perform a prostate ultrasound at the start and end of the study and we will monitor urinary symptoms, prostate specific antigen (PSA) levels and the prostate exam throughout the study.

• Aging
• Hypogonadism
• Andropause

• Drug: Anastrozole
• Drug: Testosterone Gel
• Drug: Placebo tablet
• Drug: Placebo gel
• Dietary Supplement: Calcium Cardone 500mg with vitamin D 400 IU

• Experimental: 25 participants will receive testosterone gel (5 gm) plus placebo tablet daily for 12 months
• Experimental: 25 participants will receive anastrozole 1 mg tablet plus placebo gel daily for 12 months
• Placebo Comparator: 25 participants will receive a placebo tablet and placebo gel daily for 12 months

• Gray A, Feldman HA, McKinlay JB, Longcope C. Age, disease, and changing sex hormone levels in middle-aged men: results of the Massachusetts Male Aging Study. J Clin Endocrinol Metab. 1991 Nov;73(5):1016-25.
• Purifoy FE, Koopmans LH, Mayes DM. Age differences in serum androgen levels in normal adult males. Hum Biol. 1981 Dec;53(4):499-511. No abstract available.
• Vermeulen A. Clinical review 24: Androgens in the aging male. J Clin Endocrinol Metab. 1991 Aug;73(2):221-4. Review. No abstract available.
• Morley JE, Kaiser FE, Perry HM 3rd, Patrick P, Morley PM, Stauber PM, Vellas B, Baumgartner RN, Garry PJ. Longitudinal changes in testosterone, luteinizing hormone, and follicle-stimulating hormone in healthy older men. Metabolism. 1997 Apr;46(4):410-3.

Inclusion Criteria:

• Male
• 65 years of age or older
• Testosterone level less than 350 ng/dl (we will check this level at the screening visit)
• Able to complete an informed consent

Exclusion Criteria:

• History of Stroke
• History of Dementia
• History of Diabetes
• Blood Pressure at rest of > 155/90 mm Hg
• Chronic medical condition (i.e. heart failure, rheumatoid arthritis)
• On osteoporosis medications
• On steroids (prednisone, cortisone)
• History of gastric surgery
• History of any Cancer (except non-melanoma skin cancers)
• Drink more than 2 beers OR 1 glass of wine or cocktail daily
• Smoke any tobacco product
• Started a new medication within the past three months
• History of joint replacement