title: Assessing the impact of diabetes-related comorbidities and care on the hospitalization costs for patients with diabetes mellitus in Japan.
abstract: OBJECTIVE
  Because diabetes mellitus (DM) has been highlighted in several healthcare sectors, variations in the case mix of DM should be evaluated to promote effective disease management. Using a Japanese administrative database (2003), we investigated the impact of DM-related comorbidities and of their relevant care processes on healthcare costs incurred during hospitalization.
  
  
  METHODS
  Of 283,771 hospital admissions across 174 acute care hospitals, 27,853 patients with DM were analyzed. The following variables were analyzed according to age (<65 or ≥65 years), the presence of comorbidities, demographic characteristics, procedure-related complications, insulin use, surgical procedures (percutaneous minimally invasive intervention, hemodialysis, ventilation, and rehabilitation), length of stay (LOS), and total charge (TC; US$1=Y90). Multivariate analyses were applied to investigate the effects of DM-related complications and care processes associated with DM on TC.
  
  
  RESULTS
  The mortality and procedure-related complication rates were 2.1% and 2.7%, respectively. There were significant differences in the frequencies of comorbidities by age category. Among DM-related comorbidities, peripheral vascular disease had the greatest impact on increasing the LOS or TC. Minimally invasive procedures, hemodialysis, ventilation, and procedure-related complications were significant determinants of TC. Hemodialysis and invasive surgical procedures were independent predictors of procedure-related complications.
  
  
  CONCLUSIONS
  DM-related comorbidities and care process representative of the DM case mix were responsible for variations in healthcare costs during hospitalization.
authors.affiliation: Department of Health Services Management and Policy, Graduate School of Medical Sciences, Kyushu University, Maidashi, Higashi-ku Fukuoka, Japan.
authors.forename: Dulamsuren
authors.initials: D
authors.lastname: Lkhagva
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Kuwabara
authors.forename: Shinya
authors.initials: S
authors.lastname: Matsuda
authors.forename: Yan
authors.initials: Y
authors.lastname: Gao
authors.forename: Akira
authors.initials: A
authors.lastname: Babazono
mesh_terms: D000368:Aged; D048909:Diabetes Complications / Q000191:economics* / Q000601:surgery; D003920:Diabetes Mellitus / Q000191:economics; D005260:Female; D017048:Health Care Costs; D006760:Hospitalization / Q000191:economics*; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use; D007328:Insulin / Q000627:therapeutic use; D007564:Japan / Q000453:epidemiology; D007902:Length of Stay / Q000191:economics; D008297:Male; D008875:Middle Aged; D013514:Surgical Procedures, Operative / Q000191:economics
chemical_list: D007004:Hypoglycemic Agents; D007328:Insulin