Use of Thiazolidinediones and Risk of Heart Failure in People With Type 2 Diabetes: A Retrospective Cohort Study
Response to Karter et al.
- Thomas E. Delea, MBA1,
- John S. Edelsberg, MD, MPH1,
- May Hagiwara, PHD1,
- Gerry Oster, PHD1 and
- Lawrence S. Phillips, MD2
- 1Policy Analysis, Inc. (PAI), Brookline, Massachusetts
- 2Division of Endocrinology, School of Medicine, Emory University, Atlanta, Georgia
- Address correspondence to Thomas E. Delea, MBA, Policy Analysis, Inc. (PAI), 4 Davis Ct., Brookline, MA 02445. E-mail: tdelea{at}pai2.com
We thank Karter et al. (1) for their comments regarding our study (2). We agree that its principal weakness is the possibility of residual confounding, and we acknowledge this limitation in our article. We also agree that comparison of patients initiating thiazolidinediones (TZDs) with all those receiving other oral antidiabetic agents (new starters plus those on maintenance therapy) may have biased our findings against TZDs. On the other hand, the alternative of comparing patients initiating therapy with TZDs with those initiating other oral antidiabetic agents could have imparted a potentially more serious bias to the study because (as Karter et al. note) the former may be more likely to be initiated later in the course of the disease than the latter. Lacking data on the duration of diabetes, we chose an approach that we hoped would …
