title: Changes in antidiabetic prescription patterns and indicators of diabetic control among 200,000 patients over 13 years at a single institution in Japan.
abstract: BACKGROUND
  We examined the long-term changes in the management of diabetes at a single institution in Japan.
  
  
  METHODS
  Two repeated cross-sectional studies and a retrospective cohort study were conducted among patients who visited our institution between 2001 and 2013. We examined the changes in glycated hemoglobin (HbA1c) and glycated albumin levels, the prescription frequencies, and the daily doses of each antidiabetic agent among patients treated regularly for diabetes during the 13-year study period. The trends in control and treatment parameters were analyzed using Spearman's rank correlation coefficient.
  
  
  RESULTS
  In the first repeated cross-sectional studies, 200,298 patients had their glucose metabolism indicators measured, and diabetologists prescribed medications to 193, 445 patients. Of these, 170 patients were included in the retrospective cohort study. The patients' diabetic control tended to improve over the study period. The mean HbA1c level improved from 7.9 to 7.6% (from 63 to 60 mmol/mol) (rs = -0.11, p < 0.01) in the cross-sectional study, corresponding to a change from 8.2 to 7.7% (from 66 to 61 mmol/mol) (rs = -0.22, p < 0.01) in the retrospective study. The mean GA level improved from 22.7 to 20.7% (rs = -0.13, p < 0.01) in the cross-sectional study and from 23.5 to 21.5% (rs = -0.14, p < 0.01) in the retrospective study. Over the study period, prescription frequencies and daily doses of antidiabetic agents changed as treatment guidelines were altered.
  
  
  CONCLUSIONS
  The present study revealed a tendency toward long-term improvements in diabetic control, with changes in the prescription patterns consistent with research and guideline evidence.
authors.affiliation: Department of General Medicine, School of Medicine, Juntendo University, 3-1-1, Hongo, Bunkyo-ku, Tokyo 113-8421 Japan.
authors.forename: Kazutoshi
authors.initials: K
authors.lastname: Fujibayashi
authors.affiliation: Endocrinology and Metabolism Division, NTT Medical Center Tokyo, 5-9-22 Higashi-Gotanda, Shinagawa-ku, Tokyo 141-8625 Japan.
authors.forename: Michio
authors.initials: M
authors.lastname: Hayashi
authors.affiliation: Department of General Medicine, School of Medicine, Juntendo University, 3-1-1, Hongo, Bunkyo-ku, Tokyo 113-8421 Japan.
authors.forename: Hirohide
authors.initials: H
authors.lastname: Yokokawa
authors.affiliation: Department of General Medicine, School of Medicine, Juntendo University, 3-1-1, Hongo, Bunkyo-ku, Tokyo 113-8421 Japan.
authors.forename: Toshio
authors.initials: T
authors.lastname: Naito
keywords: Control; Drug therapy; History; Numerical data