Rapid-Acting Insulin Analogues Versus Regular Human Insulin: A Meta-Analysis of Effects on Glycemic Control in Patients with Diabetes

Introduction The aim of this meta-analysis was to investigate the impact of rapid-acting insulin analogues (RAIAs) and regular human insulin (RHI) on glycemic control, including long- and short-term glycemic variability as measured by glycated haemoglobin (HbA1c) and pre- and postprandial glucose (PPG). Methods PubMed was searched for studies published between 1999 and 29 June 2016. Randomised controlled trials of patients with diabetes that assessed the effects of RAIAs or RHI on glycemic control, focusing on preprandial glucose, PPG and HbA1c, were included. Only studies that reported both means and standard deviations for those outcomes were analysed; from these data, weighted mean differences and 95% confidence intervals were generated to yield overall point estimates. The primary outcomes of the meta-analysis were the mean differences between RAIAs and RHI at the end of the study in PPG, preprandial glucose, and HbA1c. Results Twenty-seven studies (n = 7452) were included. The difference in PPG between RAIA- and RHI-treated patients was significant-in favour of RAIAs-in patients with type 1 diabetes (T1D) [- 22.2 mg/dL; 95% confidence interval (CI) - 27.4, - 17.0 mg/dL; P < 0.0001] but not in those with type 2 diabetes (T2D). For preprandial glucose, there was a non-significant trend favouring RHIs in T1D; no data were available for patients with T2D. In patients with T1D, the between-group difference in end-of-treatment (EOT) HbA1c favoured RAIAs (- 0.13%; 95% CI - 0.18, - 0.08%; P < 0.0001), but was not significant in patients with T2D. The main study limitations were the small number and heterogeneity of the included studies. Conclusions These results demonstrate that RAIAs are more effective at reducing PPG and improving HbA1c than RHIs in T1D. More data are required to assess the effect of these agents on glucose control in T2D. Plain Language Summary Plain language summary available for this article.