Abstract

Objective: Measure ghrelin and energy intake (EI) in the laboratory after pioglitazone treatment.

Research Design and Methods: Parallel 3-arm study with 51 obese diabetics randomized to either: 1) pioglitazone plus a portion-controlled diet (Pio+PC), 2) pioglitazone plus American Diabetes Association (ADA) dietary advice (Pio+ADA), or 3) metformin plus ADA advice (Met+ADA). EI and the suppressive response of a meal on ghrelin were measured at weeks 0 and 16. Mixed models tested if changes from week 0 to 16 differed by group.

Results: The Pio+ADA group had a significantly larger increase (p<.05) in EI (adjusted mean±SEM; 207±53 kcal) compared to the Pio+PC (50±46 kcal) and Met+ADA (52±49 kcal) groups. Change in restraint and disinhibition (variables associated with eating behavior) mediated weight change. Ghrelin suppression increased in the Pio+ADA group, which gained weight.

Conclusions: A portion-controlled diet attenuated the increase in EI after pioglitazone. Ghrelin responded to weight change, not pioglitazone exposure.