Comparison of the Glycemic Effects of Rosiglitazone and Pioglitazone in Triple Oral Therapy in Type 2 Diabetes
- Michael T. Tran, MD,
- Maria D. Navar, FNP and
- Mayer B. Davidson, MD
- From the Clinical Center for Research Excellence, Charles R. Drew University, Los Angeles, California
- Address correspondence and reprint requests to Mayer B. Davidson, MD, Clinical Center for Research Excellence, Charles R. Drew University, 1731 East 120th St., Los Angeles, CA 90059. E-mail: madavids{at}cdrewu.edu
To date, there have been few comparison studies between rosiglitazone and pioglitazone (1,2) and none of the two thiazolidinediones (TZDs) as a third agent in triple oral therapy. In February 2003, pioglitazone replaced rosiglitazone as the TZD on the pharmacy formulary at our hospital. This gave us the opportunity to compare the effectiveness of rosiglitazone and pioglitazone added to type 2 diabetic patients already on maximum (tolerated) doses of metformin and a sulfonylurea agent whose HbA1c (A1C) levels did not meet the American Diabetes Association goal of <7.0%.
RESEARCH DESIGN AND METHODS
Our diabetes clinic treatment algorithm mandates starting small doses of either a sulfonylurea agent or metformin and increasing the dose every 2 weeks until either a fasting plasma glucose (FPG) concentration of <130 mg/dl is attained or a maximal (tolerated in the case of metformin) dose is reached. If the FPG concentration remains >130 mg/dl, the alternate drug is added and also increased every 2 weeks. When the FPG goal is achieved, further therapeutic decisions are based on A1C levels measured 2–3 months later. Only when both agents are maximized and either the FPG concentration 2 weeks after the last increase remains >130 mg/dl or an A1C level is ≥7.0% 2–3 months after the FPG goal is reached, or at any time thereafter, is a maximal dose of a TZD added. The maximal dose is used because it can take up to …
