Effect of metformin and sulfonylurea on C-reactive protein level in well-controlled type 2 diabetics with metabolic syndrome

The objective of this study was to examine the effect of the antihyperglycemic agents metformin (insulin sensitizer) and glibenclamide (insulin secretory agent) on the serum level of C-reactive protein (CRP) in well-controlled type 2 diabetics with metabolic syndrome. The participants were diabetic patients being followed in the medical outpatient clinic of King Abdulaziz University Hospital. The inclusion criteria were type 2 diabetics with the metabolic syndrome, well-controlled blood glucose on metformin alone or glibenclamide alone, and exclusion of major medical illness. Patients were divided into two groups according to the antihyperglycemic agent used. CRP level was measured 4-wk apart and the mean was calculated. The following data were collected from the study groups: age, sex, body mass index (BMI), duration of diabetes, smoking history, presence of hypertension, hyperlipidemia, and mean CRP level. A total of 110 patients were studied, 65 using metformin and 45 using glibenclamide. CRP level was significantly lower in patients using metformin for blood glucose control compared with those using glibenclamide, 5.56 and 8.3 mg/L, respectively (p = 0.01). A significantly higher level was observed in hypertensive and hyperlipidemic patients compared with normotensive and normolipidemic, 5.3 vs 3.2 mg/L and 7.1 vs 4.3 mg/L, respectively (p = 0.02, 0.01). There was a statistically significant correlation between CRP and BMI (r = 0.37) and age (r = 0.36) (all p = 0.01). The data showed that metformin decreases the level of circulating CRP, a marker of inflammation, more than glibenclamide.