title: Association between hypoglycemia and inpatient mortality and length of hospital stay in hospitalized, insulin-treated patients.
abstract: OBJECTIVE
  To assess the impact of hypoglycemia on clinical outcomes among hospitalized, insulin-treated patients.
  
  
  METHODS
  In a retrospective study, hospitalizations in 2005-2007 were identified from a US inpatient electronic medical records database. All encounters for insulin-treated patients with valid blood glucose measurement were included, except for those with a length of stay <24 hours or >30 days. In an encounter-based analysis, associations between hypoglycemic (glucose ≤70 mg/dL) or severe hypoglycemic (glucose ≤50 mg/dL) episodes and inpatient mortality, ischemic events, neurologic complications, and length of stay were evaluated.
  
  
  RESULTS
  Among 107,312 admissions, hypoglycemia occurred in 21,561 (20%) and severe hypoglycemia in 7539 (7%). Inpatient mortality occurred in 6.5% of hospitalizations with hypoglycemia and 3.8% of those without (p < 0.001). Inpatient mortality occurred in 7.6% of hospitalizations with a severe hypoglycemic event. Ischemic events (8.1 vs. 8.0%) and neurologic complications (3.8 vs. 3.7%) were similar in hospitalizations with and without a hypoglycemic event, respectively. In multivariate logistic regression analyses adjusting for age, gender, and selected comorbidities, hypoglycemia was associated with a significant increase in inpatient mortality risk (adjusted odds ratio (OR) = 1.66 [95% CI: 1.55, 1.78]). Similar results were observed with severe hypoglycemia (adjusted OR = 1.44 [1.38, 1.52]). Length of stay was increased in hospitalizations with hypoglycemia (median [interquartile range]: 8.2 days [4.9, 13.9] vs. 5.2 days [3.1, 8.3]; p < 0.0001).
  
  
  CONCLUSIONS
  Due to the nature of the data source, some data of interest were not available, including insulin dose and dose regimen, outpatient medical histories (including diabetes history), pre-hospitalization medications, and cause of death.
  
  
  CONCLUSIONS
  Hypoglycemia was common among hospitalized patients receiving insulin and, while a direct causal relationship cannot be assumed, was associated with an increased risk of inpatient mortality and increased length of hospital stay. Hypoglycemia is an undesirable event and efforts to minimize in-hospital hypoglycemic events are warranted across the spectrum of hospitalized patients.
authors.affiliation: Merck Sharp & Dohme Corp., Whitehouse Station, NJ, USA. kimberly.brodovicz@merck.com
authors.forename: Kimberly G
authors.initials: KG
authors.lastname: Brodovicz
authors.forename: Vinay
authors.initials: V
authors.lastname: Mehta
authors.forename: Qiaoyi
authors.initials: Q
authors.lastname: Zhang
authors.forename: Changgeng
authors.initials: C
authors.lastname: Zhao
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Davies
authors.forename: Jieling
authors.initials: J
authors.lastname: Chen
authors.forename: Larry
authors.initials: L
authors.lastname: Radican
authors.forename: Samuel S
authors.initials: SS
authors.lastname: Engel
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D016001:Confidence Intervals; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D007003:Hypoglycemia / Q000150:complications / Q000401:mortality*; D007004:Hypoglycemic Agents / Q000627:therapeutic use*; D007328:Insulin / Q000627:therapeutic use*; D007902:Length of Stay; D016015:Logistic Models; D008297:Male; D008485:Medical Audit; D008875:Middle Aged; D016017:Odds Ratio; D012189:Retrospective Studies; D012720:Severity of Illness Index; D014481:United States
chemical_list: D007004:Hypoglycemic Agents; D007328:Insulin