NEW YORK (Reuters Health) – In a small pilot study of frail older women with unexplained weight loss, infusion of the appetite-stimulating hormone ghrelin led to improvement in appetite and growth hormone (GH) levels and was well tolerated.
The study findings were presented at The Endocrine Society’s annual meeting in Washington, D.C., which closed over the weekend.
The study, conducted at the University of Pennsylvania School of Medicine in Philadelphia, involved five women aged 70 or older with unintentional weight loss of greater than 5 percent, and who met at least two other criteria for frailty, and five healthy control women. The women were of similar age (approximately 80 years old) and BMI (26.2 vs 24.5).
In the double-blind, crossover trial, each woman was randomly assigned to receive two 180-minute infusions, one week apart, of ghrelin or placebo (saline). Ghrelin was given by graded infusion (2.5, 5, and 10 pmol/kg/min for 60 minutes each). A standardized meal was consumed after each infusion and intake was quantified.
Overall, women consumed 51% more calories after the ghrelin infusion than the placebo infusion, “due to increased carbohydrate (p = 0.005) and protein (p = 0.04) intake, but not fat (p = 0.38),” Dr. Anne Cappola and colleagues report in a meeting abstract.
In addition, growth hormone levels were higher at every time point during the ghrelin infusion compared to the placebo infusion (p < 0.01), as were total and active ghrelin levels (p < 0.01). “The only adverse event noted was a transient sensation of warmth in four women during the ghrelin infusion,” the authors note. Differences in ghrelin's effects between the frail and healthy women were not statistically significant. “Our study,” Dr. Cappola noted in a statement from the meeting, “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.” Based on their pilot study, the researchers say “future studies should examine the potential therapeutic role of ghrelin mimetic agents in this population.”