title: Hypoglycemia, with or without insulin therapy, is associated with increased mortality among hospitalized patients.
abstract: OBJECTIVE
  Hypoglycemia is associated with increased mortality in hospitalized patients. We investigated the relationship between spontaneous hypoglycemia versus insulin-associated hypoglycemia and mortality in hospitalized patients.
  
  
  METHODS
  Data for this retrospective cohort study were obtained from electronic databases of patients admitted between 1 April 2008 and 30 November 2010. Patients with one or more blood glucose values ≤50 mg/dL on point-of-care glucose testing were considered hypoglycemic. Patients treated with insulin were assumed to have insulin-associated hypoglycemia. Age-, sex-, and race-matched patients with all blood glucose values >70 mg/dL were selected as controls. The Charlson comorbidity index (CCI) was used to control for severity of illness.
  
  
  RESULTS
  There were four groups: 1) noninsulin-treated hypoglycemia (NTH) (n = 135), 2) insulin-treated hypoglycemia (ITH) (n = 961), 3) noninsulin-treated control (NTC) (n = 1,058), and 4) insulin-treated control (ITC) (n = 736). Mortality was higher in the ITH group compared with the ITC group (20.3 vs. 4.5%, P < 0.0001), with a relatively higher CCI (1.8 vs. 1.5%, P < 0.0001), but much higher in the NTH group compared with the NTC group (34.5 vs. 1.1%, P < 0.0001), with much higher CCI (2.4 vs. 1.1%, P < 0.0001). Mortality was higher in the NTH group compared with the ITH group (P < 0.0001) but lower in the NTC group compared with the ITC group (P < 0.0001). After controlling for age, sex, CCI, and admission to the intensive care unit, insulin treatment was associated with a lower mortality among the hypoglycemic patients; hazard ratio of death in the ITH group relative to the NTH group was 0.34 (95% CI 0.25-0.47, P < 0.0001).
  
  
  CONCLUSIONS
  Insulin-associated and spontaneous hypoglycemia are associated with increased mortality among hospitalized patients.
authors.affiliation: Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA. rgarg@partners.org
authors.forename: Rajesh
authors.initials: R
authors.lastname: Garg
authors.forename: Shelley
authors.initials: S
authors.lastname: Hurwitz
authors.forename: Alexander
authors.initials: A
authors.lastname: Turchin
authors.forename: Apoorva
authors.initials: A
authors.lastname: Trivedi
mesh_terms: D005260:Female; D017052:Hospital Mortality; D006801:Humans; D007003:Hypoglycemia / Q000188:drug therapy / Q000401:mortality* / Q000503:physiopathology*; D007004:Hypoglycemic Agents / Q000627:therapeutic use*; D007328:Insulin / Q000627:therapeutic use*; D008297:Male; D012189:Retrospective Studies
chemical_list: D007004:Hypoglycemic Agents; D007328:Insulin