Glycemic Characteristics and Clinical Outcomes of COVID-19 Patients Hospitalized in the United States

J Diabetes Sci Technol. 2020 Jul;14(4):813-821. doi: 10.1177/1932296820924469. Epub 2020 May 9.


Introduction: Diabetes has emerged as an important risk factor for severe illness and death from COVID-19. There is a paucity of information on glycemic control among hospitalized COVID-19 patients with diabetes and acute hyperglycemia.

Methods: This retrospective observational study of laboratory-confirmed COVID-19 adults evaluated glycemic and clinical outcomes in patients with and without diabetes and/or acutely uncontrolled hyperglycemia hospitalized March 1 to April 6, 2020. Diabetes was defined as A1C ≥6.5%. Uncontrolled hyperglycemia was defined as ≥2 blood glucoses (BGs) > 180 mg/dL within any 24-hour period. Data were abstracted from Glytec's data warehouse.

Results: Among 1122 patients in 88 U.S. hospitals, 451 patients with diabetes and/or uncontrolled hyperglycemia spent 37.8% of patient days having a mean BG > 180 mg/dL. Among 570 patients who died or were discharged, the mortality rate was 28.8% in 184 diabetes and/or uncontrolled hyperglycemia patients, compared with 6.2% of 386 patients without diabetes or hyperglycemia (P < .001). Among the 184 patients with diabetes and/or hyperglycemia who died or were discharged, 40 of 96 uncontrolled hyperglycemia patients (41.7%) died compared with 13 of 88 patients with diabetes (14.8%, P < .001). Among 493 discharged survivors, median length of stay (LOS) was longer in 184 patients with diabetes and/or uncontrolled hyperglycemia compared with 386 patients without diabetes or hyperglycemia (5.7 vs 4.3 days, P < .001).

Conclusion: Among hospitalized patients with COVID-19, diabetes and/or uncontrolled hyperglycemia occurred frequently. These COVID-19 patients with diabetes and/or uncontrolled hyperglycemia had a longer LOS and markedly higher mortality than patients without diabetes or uncontrolled hyperglycemia. Patients with uncontrolled hyperglycemia had a particularly high mortality rate. We recommend health systems which ensure that inpatient hyperglycemia is safely and effectively treated.

Keywords: COVID-19; Glytec; diabetes; glucose; hospital; hyperglycemia; length of stay; mortality.

Publication types

  • Observational Study

MeSH terms

  • Aged
  • Betacoronavirus
  • Blood Glucose Self-Monitoring / methods
  • COVID-19
  • Comorbidity
  • Coronavirus Infections / complications*
  • Coronavirus Infections / epidemiology
  • Coronavirus Infections / therapy*
  • Data Collection
  • Female
  • Glycated Hemoglobin / analysis
  • Hospitalization
  • Humans
  • Hyperglycemia / complications
  • Hyperglycemia / epidemiology
  • Hyperglycemia / therapy*
  • Insulin Infusion Systems
  • Length of Stay
  • Male
  • Middle Aged
  • Pandemics
  • Patient Discharge
  • Pneumonia, Viral / complications*
  • Pneumonia, Viral / epidemiology
  • Pneumonia, Viral / therapy*
  • Respiratory Distress Syndrome / complications
  • Retrospective Studies
  • Risk Factors
  • SARS-CoV-2
  • Software
  • Treatment Outcome
  • United States / epidemiology


  • Glycated Hemoglobin A
  • hemoglobin A1c protein, human