Incidence of severe nocturnal hypoglycemia in patients with type 1 diabetes treated with insulin lispro or regular human insulin in addition to basal insulin glargine

Abstract Background and aims Once-daily (OD) basal insulin glargine (GLA) can be used as part of a multiple daily injection regimen in patients with type 1 diabetes mellitus. This randomized, multicenter study compared GLA+prandial regular human insulin (RHI) with GLA+prandial insulin lispro (LIS) in reducing the incidence of severe nocturnal hypoglycemia at endpoint. In addition, the effects on glycemic control of both treatments were investigated. Methods and results Patients (489) previously on neutral protamine Hagedorn (NPH) insulin or GLAR plus RHI/LIS were switched to, or continued on GLA (target fasting blood glucose [FBG]=5.0–6.7mmol/L [90–120mg/dL]) for 8 weeks (qualification phase) prior to randomization; patients continued with their previous bolus insulin. Patients ( n =395) were then randomized to LIS ( n =193) or RHI ( n =202) and treated for 16 weeks. The proportion of patients experiencing severe nocturnal hypoglycemia at the end of the study was 1.55% ( n =3) in the RHI group and 1.11% ( n =2) in the LIS group ( p =0.938 between groups); the mean difference was 0.44% (95% CI: −1.77, 2.21), suggesting non-inferiority of RHI versus LIS. At the end of the study, both treatments did not differ with respect to glycemic control, as measured by hemoglobin A 1c and FBG. Conclusion These results suggest that GLA+LIS and GLA+RHI treatments were associated with a similar and low rate of severe nocturnal hypoglycemia. Further studies with greater patient sizes are necessary to verify the findings from the current study.