title: Insulin analogs and glycosylated hemoglobin target of less than 7% in type 2 diabetes: a systematic review of randomized trials.
abstract: BACKGROUND
  We conducted a systematic review of randomized controlled trials (RCTs) that evaluated the effectiveness of insulin regimens with insulin analogs to reach the glycosylated hemoglobin (HbA1c) target of <7% in patients with type 2 diabetes.
  
  
  METHODS
  RCTs involving insulin regimens (basal, prandial, biphasic, and basal-bolus) with insulin analogs in type 2 diabetes were identified through electronic searches [MEDLINE, EMBASE, Cumulative Index to Nursing and Allied Health Literature (CINAHL), and The Cochrane Library] through September, 2010. We included any study arm of RCTs if they were at least 12 weeks in duration and reported HbA1c as an outcome.
  
  
  RESULTS
  We identified 55 RCTs, with 96 arms and 33,244 patients, that reported the HbA1c target, and 32 RCTs, with 32 arms and 5,559 patients, that did not report the target. The missing targets were calculated with an algorithm that explained 88% of variability between studies. Overall, the proportion of patients at target (HbA1c <7%) was 37.2% [95% confidence interval (CI), 31.5-43.1%] with basal insulin, 35.3% (28.9-42.1%) with biphasic insulin, 37.5% (27.7-47.9%) with prandial insulin, and 51.2% (41.4-61.1%) for basal-bolus insulin, with high heterogeneity (I(2) >80% for all).
  
  
  CONCLUSIONS
  The HbA1c target <7% can be achieved in a proportion of patients ranging from 35% to 51%, depending on the particular insulin regimen. At least one half of patients with type 2 diabetes receiving insulin analogs do not reach the HbA1c target.
authors.affiliation: Department of Geriatrics and Metabolic Diseases, Second University of Naples, Piazza L. Miraglia, Naples, Italy.
authors.forename: Katherine
authors.initials: K
authors.lastname: Esposito
authors.forename: Maria Ida
authors.initials: MI
authors.lastname: Maiorino
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Bellastella
authors.forename: Paolo
authors.initials: P
authors.lastname: Chiodini
authors.forename: Dario
authors.initials: D
authors.lastname: Giugliano
mesh_terms: D000465:Algorithms; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000188:drug therapy* / Q000453:epidemiology; D006442:Glycated Hemoglobin / Q000032:analysis / Q000378:metabolism*; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use; D007328:Insulin / Q000031:analogs & derivatives* / Q000627:therapeutic use*; D016032:Randomized Controlled Trials as Topic / Q000706:statistics & numerical data; D016896:Treatment Outcome
chemical_list: D006442:Glycated Hemoglobin; D007004:Hypoglycemic Agents; D007328:Insulin; C517652:hemoglobin A1c protein, human