title: Frequency of hypoglycemia and its impact on length of stay, mortality, and short-term readmission in patients with diabetes hospitalized in internal medicine wards.
abstract: OBJECTIVE
  To evaluate whether hypoglycemia is associated with increases in length of stay (LOS), inpatient mortality, and readmission among patients with diabetes hospitalized in internal medicine wards.
  
  
  METHODS
  A retrospective cohort study was carried out using the Basic Minimum Data Set registry of the Spanish National Health System, which contains clinical and administrative information for every patient discharged from system hospitals. The analysis included patients discharged between January 2005 and December 2010 and had a primary (i.e., reason for the admission) or secondary diagnosis of diabetes and a secondary diagnosis of hypoglycemia. The associations between hypoglycemia and the study outcomes (mortality, readmission, and LOS) were evaluated using multivariate and multilinear regression models that included age, sex, and the Charlson index as covariates.
  
  
  RESULTS
  During the study period, 3,361,104 patients were admitted to internal medicine wards in the National Health System. Of these, 921,306 (27.4%) had diagnoses of diabetes, and among these patients, 46,408 (5%) had secondary hypoglycemia. A total of 4,754 (10.2%) patients with secondary hypoglycemia died during their hospital stays, compared with 83,508 (9.5%) patients without hypoglycemia. The multivariate/multilinear regression models demonstrated significant associations between the presence of secondary hypoglycemia and greater inpatient mortality (odds ratio [OR] 1.24, 95% confidence interval [CI] 1.20-1.28), a greater likelihood of readmission (OR 1.20, 95% CI 1.17-1.23), and an increased LOS (β 1.24, 95% CI 1.15-1.35).
  
  
  CONCLUSIONS
  Hypoglycemia in patients with diabetes hospitalized in internal medicine wards is associated with increases in the LOS, inpatient mortality, and early readmission.
authors.affiliation: Servicio de Medicina Interna, Hospital Universitario Fuenlabrada, Madrid, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: Zapatero
authors.affiliation: Servicio de Medicina Interna Hospital Regional Universitario Carlos Haya, Málaga, Spain.
authors.forename: Ricardo
authors.initials: R
authors.lastname: Gómez-Huelgas
authors.affiliation: Servicio de Endocrinología, Hospital Universitario Fuenlabrada, Madrid, Spain.
authors.forename: Noemi
authors.initials: N
authors.lastname: González
authors.affiliation: Servicio de Medicina Interna, Hospital Universitario Fuenlabrada, Madrid, Spain.
authors.forename: Jesús
authors.initials: J
authors.lastname: Canora
authors.affiliation: Servicio de Medicina Interna, Hospital Rey Juan Carlos, Móstoles.
authors.forename: Angel
authors.initials: A
authors.lastname: Asenjo
authors.affiliation: Servicio de Medicina Interna, Hospital Universitario Fuenlabrada, Madrid, Spain.
authors.forename: Juan
authors.initials: J
authors.lastname: Hinojosa
authors.affiliation: Servicio de Medicina Interna, Hospital Severo Ochoa, Leganés, Madrid, Spain.
authors.forename: Susana
authors.initials: S
authors.lastname: Plaza
authors.affiliation: Servicio de Medicina Interna, Hospital Clínico Universitario San Carlos, Madrid, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: Marco
authors.affiliation: Servicio de Medicina Interna, Hospital Rey Juan Carlos, Móstoles.
authors.forename: Raquel
authors.initials: R
authors.lastname: Barba