NutritionHormone May Help Combat Frailty In Older Women
Frail elderly women with unexplained weight loss may benefit from supplementation with the body"s appetite-stimulating hormone, ghrelin, or with similar agents, according to a new study. Results of the study, which was funded partially by the National Institutes of Health, were presented at The Endocrine Society"s 91st Annual Meeting in Washington, D.C.
Unexplained weight loss is a common problem in older adults. It can lead to the development of frailty, a debilitating syndrome of declines across multiple body systems.
Frail individuals have much higher rates of functional decline, hospitalization and death than healthier people their age, said study lead investigator Anne Cappola, MD, ScM, assistant professor of medicine at the University of Pennsylvania School of Medicine, Philadelphia.
"There are no good medical treatments for frailty or unintentional weight loss at this time," Cappola said.
The pilot study enrolled five women age 70 or older who had unintentional, unexplained weight loss of greater than 5 percent of their body weight in a year and who met at least two of the other standard criteria for frailty: self-reported exhaustion, weakness (grip strength), slow walking speed and low physical activity. The control group included five healthy women of similar age.
Each woman received two infusions into a vein, 1 week apart, of ghrelin or placebo (saline). The order was assigned randomly, and neither the women nor the person giving the infusion knew which one it was. During the 180-minute infusion, blood samples were taken to measure ghrelin levels in the body. Also measured was growth hormone response, because past studies showed an increase in growth hormone to ghrelin stimulation, and there could be benefit to raising growth hormone levels in this population, according to Cappola.
After the infusion, the women received a standardized meal, and the researchers quantified how much they ate.
Women in both groups ate 51 percent more calories after the ghrelin infusion than the placebo infusion, because of increased carbohydrate and protein intake, not fat, the authors reported. Blood levels of growth hormone and ghrelin were higher at every time point during the ghrelin infusion than during the placebo infusion. The only side effect of treatment was a transient sensation of warmth that four women experienced during the ghrelin infusion.
"Our study is the first to show an improvement in appetite and growth hormone levels after administration of the hormone ghrelin to frail older women with unexplained weight loss," Cappola said.
Future studies, she said, should examine the potential therapeutic role of ghrelin or similar agents (ghrelin mimetic agents) in this population. These agents are available only for research use now.
The University of Pennsylvania Institute on Aging also helped fund this study. Carrie Burns, MD, assistant professor of clinical medicine at the university, will present the study results.
Endocrine Society