Intensification of insulin therapy in patients with type 2 diabetes: a retrospective, non- interventional cohort study of patients treated with insulin glargine or biphasic human insulin in daily clinical practice

Background: The aim of this study is to compare the efficacy of intensification of insulin treatment with insulin glargine and biphasic human insulin in patients with type 2 diabetes on concomitant therapy with oral antidiabetic drugs (OAD) in daily clinical practice. Methods: A retrospective multicentre parallel two-arm study included 301 patients with type 2 diabetes already on treatment with biphasic human insulin twice daily (bd) in combination with OAD. Data were collected retrospectively from 142 patients who had been switched from biphasic human insulin to insulin glargine in a period of 6-12 months prior to their inclusion (active group) and compared to data collected retrospectively from 159 patients who continued treatment with biphasic human insulin bd for the same time period (control group). Our primary objective was to examine the efficacy of the two treatments, assessed as change in HbA1c. Secondary objectives were to examine for changes in fasting blood glucose (FBG), body weight, treatment with OAD or fast-acting insulin and safety, by assessing the frequency and severity of hypoglycaemic episodes. Results: At the end of the study there was a significant reduction in HbA1c in both arms. The least squares (LS) mean [(95% confidence intervals (CI)] reduction in HbA1c was -1.13 (-0.96 to -1.30)% in the active and -0.59 (-0.41to -0.77)% in the control group [LS mean treatment difference 0.53 (0.31-0.76)%, p < 0.001]. Similarly, fasting blood glucose declined significantly in both arms. The LS mean decline in FBG was -47.02 (-37.89 to -56.14) mg/dl in the active and -19.73 (-11.57 to -27.89) mg/dl in the control group [LS mean treatment difference 27.85 (15.74-39.95) mg/dl, p < 0.001]. No significant difference in hypoglycaemic episodes and in body weight was found. In the active group, more patients received rapid-acting pre-meal insulin and used insulin secretagogues drugs. Conclusions: Glargine alone or in combination with fast acting insulin is more effective in reducing glycaemia than biphasic human insulin alone or in combination with fast acting insulin in patients with type 2 diabetes without increase in hypoglycaemic episodes or body weight