Response to Comment on: Boden et al. (2007) Combined Use of Rosiglitazone and Fenofibrate in Patients with Type 2 Diabetes: Prevention of Fluid Retention: Diabetes 56:248–255

We appreciated the comments by Dr. Stroup (1) who wonders whether the baseline (pretreatment) risk for edema might have been higher in the rosiglitazone-treated group as compared with the rosiglitazone plus fenofibrate–treated group. Specifically, he asks how many patients in each group had a history of congestive heart failure or may have been treated with medications known to cause edema such as dihydropyridine calcium channel blockers or were treated with insulin, which in combination with TZDs is known to increase the risk for edema. In response to Dr. Stroup's questions, none of the volunteers in either group had a history of congestive heart failure because this was an exclusion criterion. One of the five patients in the rosiglitazone group and one of the eight patients in the rosiglitazone plus fenofibrate group were treated with a dihydropyridine calcium channel blocker. Two patients in the rosiglitazone group and one patient in the rosiglitazone plus fenofibrate group received insulin. All five patients in the rosiglitazone group had an increase in body water, even though three of five did not receive insulin. In contrast, body water increased in only two of eight patients in the rosiglitazone plus fenofibrate group, while six patients lost body water (including the patient who was treated with insulin). Thus, we believe that it is unlikely that these findings can be explained by an increased baseline risk for edema in the rosiglitazone group, although a much larger trial will be needed to rule out this possibility and confirm our results.