Comparative evaluation of biphasic insulin with metformin and triple oral hypoglycemic agents (OHA) in type 2 diabetes patients

Introduction: The prevalence of secondary failure to oral hypoglycemic agents among type 2 diabetes mellitus (T2DM) patients ranges from 30 to 60%. The alternative approaches to overcome this issue are either switching to triple oral hypoglycemic agents (OHA) or intensifying the regimen by adding insulin. Objective: To compare the glycemic control achieved with biphasic insulin plus metformin and triple OHA in T2DM patients who were not adequately controlled with two OHA regimen. Methods: A qualitative prospective study was conducted at Asir diabetes center, Abha, KSA. Poorly controlled T2DM patients with two OHA for at least 1 year with glycated hemoglobin (HbA1c) >7.0% were included. Subjects were divided into group I (a third OHA was added to the existing two OHA regimen) and group II (switched over to Biphasic insulin and metformin). At baseline and 3-month intervals, level of HbA1C, Fasting Plasma Glucose (FPG), Postprandial Plasma Glucose (PPG), Blood Pressure (BP), lipid profile and hypoglycemic episodes were obtained and evaluated for one year. Results: 41.1% of patients were in group I and 58.9% were in group II. At the end of the study, there was a significant reduction in HbA1c in group II subjects comparing to group I (8.18 ± 1.32 vs 8.79 ± 1.81, p = 0.0238). FPG and PPG were improved also in group II. The mean body weight increased from baseline in group II is +4.48 kg and decreased from baseline in group I (−0.46 kg). 11.3% from group I and 23.7% from group II reported hypoglycaemic incidences. Conclusion: Biphasic insulin and metformin regimen could be an appropriate therapeutic option for achieving good glycemic control compared with triple OHA in patients with two OHA failure. Keywords: Glycaemic control, Type 2 diabetes, Biphasic insulin, Metformin, Oralhypoglycemic agents