This is an excellent question. A recent meta-analysis (Nissen SE, Wolski K. NEJM 2007; 356[24]:2457-71) suggested that rosiglitazone, a drug used to treat type 2 diabetes, was associated with an increased risk of heart disease. Specifically, in the 42 relevant studies, 86 patients on this medication had a myocardial infarction in the period under study vs 72 in the control group, with 39 deaths vs 22 in controls. The clinical significance of this finding remains unclear. So it would be prudent to avoid the use of rosiglitazone in individuals with a pre-existing history of heart disease or with significant risk factors. If your patients are well controlled on this agent and have no major risk factors for heart disease beyond diabetes mellitus, however, I would continue therapy, albeit after discussion as to the controversy. Please note that many of the alternatives to rosiglitazone may have different adverse effects or diminished efficacy.