Context: Treatment of adult growth hormone deficiency (AGHD) with daily injections of GH results in decreased adipose mass, increased lean body mass (LBM), increased bone mineral density, and improved quality of life.

Objective: To determine if a depot preparation of GH given every 14 days would lead to comparable decreases in trunk adipose tissue as daily GH.

Design: Open-label, randomized study comparing subjects receiving depot GH, daily GH or no therapy.

Setting: 23 university or local referral endocrine centers.

Patients or Other Participants: 135 adults with AGHD syndrome.

Intervention: Subjects randomized to receive depot GH (n = 51), daily GH (n = 53) or no treatment (n = 31) for 32 wks. The dose of GH was titrated so that IGF-I +2SD the age-adjusted normal range.

Main Outcome Measure: Trunk adipose tissue as measured by dual energy x-ray absorptiometry.

Results: The percentage of the trunk region that is fat increased by 0.4 in the no treatment group, but decreased by 3.2 (P = 0.001 vs. untreated) in the GH depot group and by 2.5 (P < 0.004 vs. untreated) in the daily GH group. Visceral adipose tissue area decreased by 9.1% in the GH depot group and by 6.8% in the daily GH group. LBM and HDL increased in both treatment groups. Side effect profiles were similar. Three subjects receiving GH experienced serious episodes of adrenal insufficiency.

Conclusions: GH diminishes trunk and visceral adipose tissue and increases LBM in AGHD. A depot form of GH which is administered every 14 days is as safe and effective as daily GH injections.