The purpose of the study is to examine whether DHEA replacement therapy is associated with beneficial changes in body composition (i.e., increases in lean mass and bone mass, and decreases in fat mass).

The central hypothesis of this study is that restoring circulating levels of the adrenal hormone dehydroepiandrosterone (DHEA) in older people with low levels to more youthful levels will be associated with beneficial changes in lean mass, fat mass and bone mass.

This will be a randomized, placebo-controlled, double-blinded study. Seventy-two men and 72 women, over 60 years old, who are healthy, will be randomized to receive either a replacement dose of DHEA or placebo for 1 year. The replacement dose of DHEA will bring circulating DHEA sulfate (DHEAS) levels into the range of normal in healthy 20-30 year-old women (approximately 8 micromoles per liter [μM] or 295 micrograms per deciliter [µg/dL]) and men (approximately 10 micromoles per liter [μM] or 368 micrograms per deciliter [µg/dL]).

Fat mass and fat-free body mass will be evaluated by dual energy x-ray absorptiometry (DXA), and intra-abdominal fat volume and thigh muscle area will be measured by computed tomography (CT). Bone mineral density (BMD) of the total body, lumbar spine, and proximal femur will be measured by DXA and biochemical markers of bone resorption and formation. Glucose tolerance and insulin response will be evaluated using an oral glucose tolerance test.

If this study confirms the results of a previous preliminary study, the current study is likely to impact future scientific study regarding the role of DHEA deficiency in the biology of aging and its role as a therapeutic agent for the prevention of sarcopenia.

Inclusion Criteria:

• Healthy women and men
• Age 60 or older
• Age-appropriate DHEAS levels, but 70% lower than normal DHEAS levels for a 25-year old

Exclusion Criteria:

• Contraindications to DHEA treatment (personal history of breast cancer or other estrogen-dependent neoplasms, acute liver disease, undiagnosed vaginal bleeding in women, history or evidence of prostate cancer or benign prostatic hyperplasia (BPH) in men)
• Angina
• Resting blood pressure over 180/95
• Chronic infections
• Hypothyroidism
• Depression
• Hormone therapy within the previous 6 months
• Insulin-dependent or poorly controlled diabetes
• Serum DHEAS level greater than 140 micrograms per deciliter (µg/dL)

Prohibited Medications:

• Hormone therapy other than stable regimen of thyroid replacement
• Oral glucocorticoids
• Insulin