The New England

Journal of Medicine

Volume 323           			July 5, 1990              		Number 1

EFFECTS OF HUMAN GROWTH HORMONE IN MEN OVER 60 YEARS OLD
Daniel Rudman, M.D., Axel G. Feller, M.D., Hoskote S. Nagraj, M.D., Gregory A. Gergans, M.D., Pardee Y. Lalitha, M.D., Allen F. Goldberg, D.D.S., Robert A. Schlenker, Ph.D., Lester Cohn, M.D., Inge W. Rudman, B.S., and Dale E. Mattson, Ph.D.

Abstract Background. The declining activity of the growth hormone-insulin-like growth factor 1 (IGF-1) axis with advancing age may contribute to the decrease in lean body mass and the increase in mass of adipose tissue that occur with aging.

Methods. To test this hypothesis, we studied 21 healthy men from 61 to 81 years old who had plasma 1GF-1 concentrations of less than 350 U per liter during a six-month base-line period and a six-month treatment period that followed. During the treatment period, 12 men (group 1) received approximately 0.03 mg of biosynthetic human growth hormone per kilogram of body weight subcutaneously three times a week, and 9 men (group 2) received no treatment. Plasma 1GF-1 levels were measured monthly. At the end of each period, we measured lean body mass, the mass of adipose tissue, skin thickness (epidermis plus dermis), and bone density at nine skeletal sites.

Results. In group 1, the mean plasma 1GF-1 level rose into the youthful range of 500 to 1500 U per liter during treatment, whereas in group 2 it remained below 350 U per liter. The administration of human growth hormone for six months in group 1 was accompanied by an 8.8 percent increase in lean body mass, a 14.4 percent decrease in adipose-tissue mass, and a 1.6 percent increase in average lumbar vertebral bone density (Proximal femur. In group 2 there was no significant change in lean body mass, the mass of adipose tissue, skin thickness, or bone density during treatment.

Conclusions. Diminished secretion of growth hormone is responsible in part for the decrease of lean body mass, the expansion of adipose-tissue mass, and the thinning of the skin that occurs in old age. (New England Journal of Medicine, 1990; 323:1-6).