Carvedilol versus beta-1 blockers as anti-hypertensive drugs in type-2 diabetes mellitus and pre-diabetic patients with features of metabolic syndrome: a meta-analysis

Background: It is unclear and contradictory on to whether carvedilol is preferable over beta-1 blockers as add-on drug in hypertensive pre-diabetic and diabetic patients with metabolic syndrome. The objective of this study was to compare the effects of carvedilol versus beta-1 blockers on hemodynamic parameters, indicators of insulin resistance and plasma lipid levels in hypertensive diabetic and pre-diabetic patients with features of metabolic syndrome.Methods: Electronic database search in Pubmed, Cochrane library and EMBASE was conducted. Randomized or cross-over studies comparing effects of carvedilol against beta-1 blockers were included under analysis. Statistical analysis by inverse variance method and both random and fixed effect models was conducted by using RevMan 5.3.Results: Six studies were eligible and included in the analysis. There was minor but significant decrease in SBP (mean difference, MD = -1.38mm Hg, 95% CI = -2.09,-0.66) and HbA1C% (MD = -0.21%, 95% CI -0.41 to -0.02) by carvedilol in patients with type-2 DM.Conclusions: There is moderate quality of evidence to suggest that carvedilol has mild but significant SBP and HbA1C% lowering effect compared to beta-1 blockers in hypertensive patients with type-2 DM.