Efficacy of Insulin Analogs in Achieving the Hemoglobin A(1c) Target of <7% in Type 2 Diabetes: Meta-analysis of randomized controlled trials

OBJECTIVE: Insulin analogs are increasingly used in patients with type 2 diabetes. We compared the effect of basal, biphasic, prandial, and basal-bolus insulin regimens with insulin analogs to reach the hemoglobin A(1c) (HbA(1c)) target of <7% in people with type 2 diabetes. RESEARCH DESIGN AND METHODS: We conducted an electronic search for randomized controlled trials (RCTs) involving insulin analogs. RCTs were included if they lasted at least 12 weeks, reported the proportion of diabetic patients reaching the HbA(1c) target of <7% (primary outcome), and the number of patients in any arm was >30. RESULTS: We found 16 RCTs, with 20 comparisons and 7,759 patients. A greater proportion of patients achieved the HbA(1c) goal of <7% with both biphasic (odds ratio 1.88 [95% CI 1.38–2.55]) and prandial (2.07 [1.16–3.69]) insulin compared with basal insulin; this was associated for biphasic insulin with greater hypoglycemia (event/patient/30 days, mean difference, 0.34 [range 0–0.69]) and weight gain in kg (1.0 kg [0.28–1.73]). Compared with biphasic insulin, the basal-bolus regimen was associated with a greater chance to reach the HbA(1c) goal (odds ratio 1.75 [95% CI 1.11–2.77]), with no greater hypoglycemia or weight gain. The effect of insulin analogs on long-term diabetes complications is still lacking. CONCLUSIONS: A greater proportion of type 2 diabetic patients can achieve the HbA(1c) goal <7% with biphasic or prandial insulin compared with basal insulin; in absolute terms, the basal-bolus regimen was best for the attainment of the HbA(1c) goal.