Hospitalised COVID-19 patients of the Mount Sinai Health System: a retrospective observational study using the electronic medical records

BMJ Open. 2020 Oct 26;10(10):e040441. doi: 10.1136/bmjopen-2020-040441.

Abstract

Objective: To assess association of clinical features on COVID-19 patient outcomes.

Design: Retrospective observational study using electronic medical record data.

Setting: Five member hospitals from the Mount Sinai Health System in New York City (NYC).

Participants: 28 336 patients tested for SARS-CoV-2 from 24 February 2020 to 15 April 2020, including 6158 laboratory-confirmed COVID-19 cases.

Main outcomes and measures: Positive test rates and in-hospital mortality were assessed for different racial groups. Among positive cases admitted to the hospital (N=3273), we estimated HR for both discharge and death across various explanatory variables, including patient demographics, hospital site and unit, smoking status, vital signs, lab results and comorbidities.

Results: Hispanics (29%) and African Americans (25%) had disproportionately high positive case rates relative to their representation in the overall NYC population (p<0.05); however, no differences in mortality rates were observed in hospitalised patients based on race. Outcomes differed significantly between hospitals (Gray's T=248.9; p<0.05), reflecting differences in average baseline age and underlying comorbidities. Significant risk factors for mortality included age (HR 1.05, 95% CI 1.04 to 1.06; p=1.15e-32), oxygen saturation (HR 0.985, 95% CI 0.982 to 0.988; p=1.57e-17), care in intensive care unit areas (HR 1.58, 95% CI 1.29 to 1.92; p=7.81e-6) and elevated creatinine (HR 1.75, 95% CI 1.47 to 2.10; p=7.48e-10), white cell count (HR 1.02, 95% CI 1.01 to 1.04; p=8.4e-3) and body mass index (BMI) (HR 1.02, 95% CI 1.00 to 1.03; p=1.09e-2). Deceased patients were more likely to have elevated markers of inflammation.

Conclusions: While race was associated with higher risk of infection, we did not find racial disparities in inpatient mortality suggesting that outcomes in a single tertiary care health system are comparable across races. In addition, we identified key clinical features associated with reduced mortality and discharge. These findings could help to identify which COVID-19 patients are at greatest risk of a severe infection response and predict survival.

Keywords: COVID-19; epidemiology; health informatics; infectious diseases.

Publication types

  • Observational Study

MeSH terms

  • Age Factors
  • Betacoronavirus / isolation & purification*
  • COVID-19
  • COVID-19 Testing
  • Clinical Laboratory Techniques / statistics & numerical data
  • Comorbidity
  • Coronavirus Infections* / diagnosis
  • Coronavirus Infections* / epidemiology
  • Coronavirus Infections* / therapy
  • Electronic Health Records / statistics & numerical data
  • Ethnicity
  • Female
  • Hospital Mortality
  • Hospitalization / statistics & numerical data*
  • Humans
  • Intensive Care Units / statistics & numerical data*
  • Male
  • Middle Aged
  • Mortality
  • New York City / epidemiology
  • Pandemics*
  • Pneumonia, Viral* / epidemiology
  • Pneumonia, Viral* / therapy
  • Retrospective Studies
  • Risk Factors
  • SARS-CoV-2