Objective: C-reactive protein (CRP) is closely associated with obesity and cardiovascular disease in both diabetic and nondiabetic populations. In the short term, commonly prescribed antidiabetic agents have different effects on CRP; however, the long-term effects of those agents are unknown.
Research design and methods: In A Diabetes Outcome Progression Trial (ADOPT), we examined the long-term effects of rosiglitazone, glyburide, and metformin on CRP and the relationship among CRP, weight, and glycemic variables in 904 subjects over 4 years.
Results: Baseline CRP was significantly correlated with homeostasis model assessment of insulin resistance (HOMA-IR), A1C, BMI, waist circumference, and waist-to-hip ratio. CRP reduction was greater in the rosiglitazone group by -47.6% relative to glyburide and by -30.5% relative to metformin at 48 months. Mean weight gain from baseline (at 48 months) was 5.6 kg with rosiglitazone, 1.8 kg with glyburide, and -2.8 kg with metformin. The change in CRP from baseline to 12 months was correlated positively with change in BMI in glyburide (r = 0.18) and metformin (r = 0.20) groups but not in the rosiglitazone (r = -0.05, NS) group. However, there was no longer a significant correlation between change in CRP and change in HOMA-IR, A1C, or waist-to-hip ratio in any of the three treatment groups.
Conclusions: Rosiglitazone treatment was associated with durable reductions in CRP independent of changes in insulin sensitivity, A1C, and weight gain. CRP in the glyburide and metformin groups was positively associated with changes in weight, but this was not the case with rosiglitazone.
Trial registration: ClinicalTrials.gov NCT00279045.