A medication that stimulates normal growth hormone secretion could help stave off physical weakness or frailty in older patients, researchers report. As people age, declining levels of growth hormone may contribute to the loss of muscle mass, contributing to frailty. Given orally, an experimental oral drug known as MK-677 seems to restore growth hormone levels.
In a study, 65 healthy adults ages 60 to 81 received either MK-677 or a placebo once daily for 1 year. Then the participants who received placebo started taking the drug and those who received the drug during the first year were randomly assigned to continue receiving it or to receive placebo instead.
In participants receiving MK-677, growth hormone levels increased to those of healthy young adults, resulting in an increase in fat-free mass (most of which was muscle). Their appetites increased and body weight rose by 5.9 pounds (2.7 kg), compared with 1.8 pounds (0.8 kg) while taking placebo. Loss of muscle mass and decreased appetite are hallmarks of frailty. However, the treatment, which was generally "well tolerated," didn't improve participants' muscle strength or function.
Researchers recommend long-term studies with more participants to investigate clinical benefits and costs associated with the treatment.
Source: Nass R, Pezzoli SS, Oliveri MC, et al. Effects of an oral ghrelin mimetic on body composition and clinical outcomes in healthy older adults. Ann Intern Med. 2008;149(9): 601-611.