Malnutrition is a common complication in patients on dialysis

and is strongly associated with poor prognosis. Effective

therapy could substantially improve morbidity and mortality,

but neither enteral nor parenteral supplementation provide

long-term benefit because of the strong appetite suppression

seen in such patients. We performed a double-blinded

randomized crossover study of a week-long treatment with

daily subcutaneous ghrelin, a gut hormone that regulates

hunger through the hypothalamus, in a group of 12

malnourished dialysis patients. Ghrelin administration

increased ghrelin levels in circulation, modestly reduced

blood pressure for up to 2 h, and immediately and

significantly increased appetite, with an increase in energy

intake noted at the first study meal. Persistence of this effect

throughout the week was confirmed with food diaries and

final study meals. Energy expenditure, measured with freeliving

pulse and motion monitors, was unchanged by ghrelin.

Our study shows that daily treatment with ghrelin achieves a

sustained positive change in energy balance in malnourished

dialysis patients. Direct manipulation of appetite with ghrelin

or its analogs represents an attractive and promising

therapeutic strategy for this difficult clinical problem.