title: Diabetes Affects Length of Stay and Hospital Costs for Elderly Patients with Pneumonia: An Analysis of a Hospital Administrative Database.
abstract: OBJECTIVE
  The present study investigated the association of having diabetes with length of stay and hospital costs for elderly patients with pneumonia who were admitted to an acute-care hospital in Japan.
  
  
  METHODS
  Based on the inpatient administrative claims database of an acute-care hospital in central Tokyo between 2010 and 2013, 753 patients aged ≥ 65 years who were admitted to the hospital presenting with pneumonia and discharged alive were analyzed. The association was analyzed using a negative binomial model, having adjusted for age, sex, body mass index, dyspnea grade, functional evaluation of feeding, use of mechanical ventilation, and use of renal replacement therapy. A log-linear regression model adjusted for the same variables was used in the analysis of hospital costs.
  
  
  RESULTS
  Of the 753 patients (mean age, 82.5 years; men, 58.2%), 225 patients had diabetes. The negative binomial regression revealed that those with diabetes had a 1.19 times longer length of stay (95% CI = 1.06-1.33) compared to those without. The log-linear regression revealed that hospital costs were 1.14 times higher (95% CI = 1.04-1.25) in patients with diabetes.
  
  
  CONCLUSIONS
  The presence of diabetes significantly correlated with longer length of stay and higher hospital costs for elderly patients with pneumonia.
authors.affiliation: Division of General Internal Medicine, Department of Internal Medicine, Tokai University Hachioji Hospital, 1838 Ishikawa-machi, Hachioji, Tokyo 192-0032, Japan. kabeya@tsc.u-tokai.ac.jp.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Kabeya
authors.forename: Akira
authors.initials: A
authors.lastname: Shimada
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Tsukada
authors.forename: Yoshihito
authors.initials: Y
authors.lastname: Atsumi
authors.forename: Megumu
authors.initials: M
authors.lastname: Higaki
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D016208:Databases, Factual; D048909:Diabetes Complications / Q000191:economics*; D005260:Female; D006739:Hospital Administration; D017721:Hospital Costs / Q000706:statistics & numerical data*; D006801:Humans; D007902:Length of Stay / Q000706:statistics & numerical data*; D016014:Linear Models; D008297:Male; D011014:Pneumonia / Q000191:economics*