Patients with type 2 diabetes inadequately controlled on premixed insulin: effect of initiating insulin glargine plus oral antidiabetic agents on glycaemic control in daily practice*

AIM: Premixed insulin regimens are commonly used for type 2 diabetes mellitus (T2DM) patients. However, there is limited information regarding next-step therapy options in cases where premixed insulin does not provide adequate glycaemic control. This 12-week observational study of everyday clinical practice evaluated the efficacy and safety of insulin glargine (glargine) plus oral antidiabetic drugs (OADs) in T2DM patients previously treated with premixed insulin. METHODS: Type 2 diabetes mellitus patients taking premixed insulin were identified from German clinics and were eligible to switch to glargine plus OADs at the physicians’ and patients’ discretion, as part of routine clinical practice. The study design and conduct was in accordance with German regulations. Fasting blood glucose (FBG), 2-h postprandial blood glucose (PPBG) and glycosylated haemoglobin (HbA(1c)) were measured at the start and after a 12-week observation period. RESULTS: A total of 5045 patients were followed-up and received glargine plus OADs. FBG [start to end-point: 9.9 ± 2.7 to 6.9 ± 1.5 mmol/l (178 ± 48 to 124 ± 26 mg/dl); p ≤ 0.001], 2-h PPBG [10.8 ± 2.8 to 7.8 ± 1.5 mmol/l (195 ± 50 to 140 ± 27 mg/dl)] and HbA(1c) (8.3 ± 1.2 to 7.2 ± 0.8%; p ≤ 0.001) improved significantly from start to end-point, respectively. A total of 48.9%, 38.4% and 73.9% of patients had FBG < 6.7 mmol/l (< 120 mg/dl), 2-h PPBG < 7.2 mmol/l (< 130 mg/dl) or HbA(1c) < 7.5%, respectively, after 12 weeks. Significant reductions in body weight were observed between the start and end of the observation period. A total of 71 adverse events were reported by 38 patients. Hypoglycaemia was the most common event (n = 16). CONCLUSIONS: This observational study shows that, in T2DM patients inadequately controlled with premixed insulin, switching therapy to glargine plus OADs is associated with significant improvements in FBG and HbA(1c), and is well tolerated in everyday clinical practice. Further intensification of insulin therapy, perhaps by adding one or more injections of prandial insulin, would help provide further improvements in glycaemic control in these patients.