Researchers have long understood that thiazolidinediones (TZDs) improve the action of insulin while increasing total fat mass as well. After studying 39 upper-body obese, insulin-resistant, but non-diabetic men and postmenopausal women, researchers concluded that patients on pioglitazone (Actos) improved their insulin resistance level regardless of the rise in intra-abdominal fat that accompanied the therapy.
Half the patients in the study were randomly assigned to receive 30 mg daily of Actos, while the other half participated in a diet and exercise program that yielded an approximate 12-kg weight loss over 20 weeks.
In spite of the increase in total body fat, particularly in the lower body, the patients on Actos experienced an improvement in insulin sensitivity.
Diabetes Care, November 2003