Comparison of efficacy and safety of two starting insulin regimens in non-Asian, Asian Indian, and East Asian patients with type 2 diabetes: a post hoc analysis of the PARADIGM study

OBJECTIVE The objective of this study was to explore the efficacy and safety of insulin lispro mix 25 (25% insulin lispro and 75% insulin lispro protamine suspension [LM25]) or insulin glargine plus insulin lispro (G+L) in insulin-naïve patients with type 2 diabetes from different racial/ethnic groups. METHODS Three subgroups from the PARADIGM study were analyzed post hoc: non-Asian (n=130), Asian Indian (n=106), and East Asian (n=89). RESULTS All subgroups recorded glycated hemoglobin (HbA1c) reductions: non-Asian (LM25, -2.07%; G+L, -2.05%), Asian Indian (LM25, -1.75%; G+L, -1.60%), and East Asian (LM25, -2.03%; G+L, -1.76%); end point HbA1c values were higher in Asian Indians and East Asians than in non-Asians. Fewer Asian Indians (LM25, 43.2%; G+L, 29.2%) and East Asians (LM25, 37.5%; G+L, 36.1%) reached HbA1c <7% versus non-Asians (LM25, 51.7%; G+L, 48.1%); differences were not significant (P=0.12 and P=0.06, respectively). The mean total daily insulin dose (U/kg) for non-Asians was 0.67 (LM25) and 0.61 (G+L), for Asian Indians was 0.91 (LM25) and 0.90 (G+L), and for East Asians was 0.53 (LM25) and 0.59 (G+L). The ratio of mealtime to total insulin dose in the G+L arm for non-Asians was 0.19±0.23, for Asian Indians was 0.33±0.25, and for East Asians was 0.34±0.27. Overall incidence (%) of hypoglycemia in non-Asians was 94.1 (LM25) and 91.8 (G+L), in Asian Indians was 90.4 (LM25) and 88.5 (G+L), and in East Asians was 69.8 (LM25) and 77.3 (G+L). CONCLUSION Asian Indians showed least improvement in glycemic HbA1c reduction despite greater insulin use. East Asians and non-Asians achieved similar HbA1c reduction in the LM25 arm with a lower rate of hypoglycemia. Asians required more mealtime insulin coverage than non-Asians. This study added important insight into the effect of ethnicity on insulin treatment outcomes in patients with type 2 diabetes.