title: A Reduction of HbA1c after 3 Months Predicts 2-year Responsiveness to Sitagliptin Treatment.
abstract: OBJECTIVE
  This retrospective study evaluated the long-term efficacy of sitagliptin and the factors contributing to its glucose-lowering effect.
  
  
  METHODS
  Six hundred and sixteen dipeptidyl peptidase-4 inhibitor-naïve outpatients with type 2 diabetes who began sitagliptin treatment between December 1, 2009 and December 31, 2011 were included in this study. The inclusion criteria were that the patient had regularly visited our hospital for a period of ≥700 days from the initiation of sitagliptin treatment and the measurement of hemoglobin A1c (HbA1c) had been performed at 0, 3, 6, 12, 18, and 24 months after the initiation of treatment. From the population of 616 patients, 447 and 169 had received sitagliptin for ≥700 and <700 days, respectively. The primary endpoint was ΔHbA1c at 24 months. The factors associated with the hypoglycemic effect of sitagliptin were also investigated.
  
  
  RESULTS
  Sitagliptin treatment significantly decreased the level of HbA1c, and the hypoglycemic effect was sustained for at least 2 years. The baseline HbA1c level, duration of diabetes, Δbody weight value, and ΔHbA1c value at 3 months were independently associated with the hypoglycemic effect of sitagliptin.
  
  
  CONCLUSIONS
  Sitagliptin has a long-term hypoglycemic effect in type 2 diabetes patients. A patient's ΔHbA1c at 3 months may be a predictor of their ΔHbA1c at 24 months.
authors.affiliation: Department of Internal Medicine, School of Medicine, Keio University, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nishimura
authors.forename: Shu
authors.initials: S
authors.lastname: Meguro
authors.forename: Risa
authors.initials: R
authors.lastname: Sekioka
authors.forename: Karin
authors.initials: K
authors.lastname: Tanaka
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Saisho
authors.forename: Junichiro
authors.initials: J
authors.lastname: Irie
authors.forename: Masami
authors.initials: M
authors.lastname: Tanaka
authors.forename: Toshihide
authors.initials: T
authors.lastname: Kawai
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Itoh
mesh_terms: D000328:Adult; D001835:Body Weight; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000188:drug therapy*; D005260:Female; D006442:Glycated Hemoglobin / Q000187:drug effects*; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D000068900:Sitagliptin Phosphate / Q000627:therapeutic use*; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D006442:Glycated Hemoglobin; D007004:Hypoglycemic Agents; D000068900:Sitagliptin Phosphate; C517652:hemoglobin A1c protein, human