Abstract
Thiazolidinediones have become a powerful tool for lowering insulin resistance. In many short-term clinical studies, many patients taking thiazolidinediones experience significant improvement in glycemic control and lipid profiles without any adverse effects. Health care providers should be aware that, in long-term follow-up, peripheral edema and congestive heart failure may occur in patients with multiple comorbidities more than 26 weeks after starting thiazolidinediones. This article reports two patients who developed congestive heart failure 6 to 12 months after starting rosiglitazone, in combination with insulin. The patients' glycemic control improved over the first 3 to 6 months of therapy. When edema and congestive heart failure occurred later, they recovered only after medical therapy (diuretics, afterload reduction) was titrated and the rosiglitazone was withdrawn.