TUESDAY, Jan. 27, 2009 (HealthDay News) -- A drug designed to increase the body's production of growth hormone may help treat frailty in older adults, a new study shows.
Older adults have greatly reduced production of growth hormone, which regulates metabolism and helps build muscle mass. Age-related decreases in strength and physical agility can led to disability and loss of independence.
"By boosting the production of growth hormones, we may be able to slow this process and help people lead active lives longer," study first author Dr. Heidi K. White, an associate professor of medicine at Duke University Medical Center, said in a Duke news release.
The study included 395 women and men, aged 65 to 84, with mild physical function limitations. They were randomly selected to take either a placebo or one of four doses of the investigational drug capromorelin. All four doses of the drug increased growth hormone production, and the findings were sustained over one year of treatment.
The researchers also found that participants who took the drug showed a significant increase in lean body mass (1.4 kilograms vs. 0.3 kg for placebo) and improvements in two physical function tests -- tandem walking (heel to toe) and stair climbing. Fatigue, insomnia and small increases in fasting glucose and HbA1c scores were among the side effects noted among those who took the drug.
The findings were released online and were expected to be published in the April issue of The Journal of Clinical Endocrinology & Metabolism. The study was funded by Pfizer, which developed capromorelin.
While the results suggest that stimulating growth hormone production can increase the body's ability to develop lean muscle, the physical improvements seen in the study were relatively mild.
For example, the patients who took the drug showed a 7 percent increase in their ability to climb stairs. A previous study found that a home-based exercise program among a similar patient population achieved a 23 percent to 24 percent improvement in stair-climbing ability after 10 weeks.
"Following further investigation, capromorelin could be used in combination with exercise," White suggested.
The AGS Foundation for Health in Aging has more about physical activity.