After myocardial infarction carvedilol improves insulin resistance compared to metoprolol

Both carvedilol and metoprolol have cardioprotective effects and decrease infarct size in myocardium. We compared effects of carvedilol and metoprolol on insulin resistance and serum lipid levels after myocardial infarction.

Fifty-nine patients aged between 30 and 70 and BMI = 25-30 kg/m2, who were diagnosed with myocardial infarction with ST segment elevation, were considered to be eligible for the study. Patients were randomly allocated to two different therapy protocols. Metoprolol 100 mg bid or carvedilol 25 mg bid was added to their standardized therapy regimen. Baseline to week 4 and 12, fasting blood glucose, serum lipid profile, BMI, C-peptide, insulin and homeostasis model assessment of insulin resistance (HOMA-IR) were measured.

After 12 weeks of metoprolol therapy HOMA-IR, insulin and C-peptide levels were significantly higher (p < 0.05 for all) and total cholesterol and triglyceride levels decreased significantly (p < 0.05 for all) compared to baseline. After 12 weeks of carvedilol therapy HOMA-IR, insulin and C-peptide (p < 0.05 for all), total cholesterol and triglyceride (p = 0.001 for all) decreased significantly compared to baseline. Carvedilol provided more decrease in total cholesterol and LDL levels than metoprolol (p = 0.043 and p = 0.021, respectively).

In patients after myocardial infarction, carvedilol added to background therapy improved insulin resistance and lipid profile.