BACKGROUND AND PURPOSE:

• Piroth et al. (Lancet Respiratory Medicine, 2020) compared patients hospitalized with COVID-19 vs those with influenza

METHODS:

• Retrospective cohort study
• Data sources
  • French national administrative database (PMSI)
  • Includes discharge summaries for all hospital admissions in France
• Participants
  • Patients hospitalized with COVID-19 from March 1 to April 30, 2020
  • Patients hospitalized with influenza from Dec 1, 2018, and Feb 28, 2019
• Study design
  • The authors compared risk factors, clinical characteristics, and outcomes between patients hospitalized with COVID-19 and influenza
  • Stratified by age group

RESULTS:

• Patient cohorts
  • COVID-19: 89,530 patients
  • Influenza: 45,819 patients
• Median age
  • COVID-19: 68 years (IQR 52 to 82)
  • Influenza: 71 years (IQR 34 to 84)

Risk Factors

• COVID-19 vs influenza patients were more likely  
  • To be obese or overweight
  • To have diabetes, hypertension, and dyslipidemia
• Influenza patients vs COVID-19 patients more frequently
  • Had heart failure, chronic respiratory disease, cirrhosis, and deficiency anemia

Clinical Characteristics

• COVID-19 vs influenza patients more frequently developed
  • Acute respiratory failure, pulmonary embolism, septic shock, or hemorrhagic stroke
• COVID-19 patients vs influenza patients less frequently developed
  • Myocardial infarction or atrial fibrillation

Outcomes

• In-hospital mortality was higher in patients with COVID-19 than in patients with influenza
  • COVID-19: 16.9%
  • Influenza: 5.8%
  • Relative risk of death from COVID-19 of 2.9 (95% CI, 2.8 to 3.0)
  • Age-standardized mortality ratio: 2.82
• The proportion of pediatric patients (<18 years) was smaller for COVID-19 than for influenza
  • COVID-19: 1.4%
  • Influenza: 19.5%
• Larger proportion of patients >5 years needed ICU support for COVID-19 than for influenza
  • COVID-19: 2.3%
  • Influenza: 0.9%
• For adolescents, the in-hospital mortality was 10x higher for COVID-19 than influenza
  • COVID-19: 1.1%
  • Influenza: 0.1%
• No difference seen between COVID-19 and influenza severity among patients living with HIV

CONCLUSION:

• Compared to influenza, COVID-19 is more likely to have respiratory pathogenicity and consequent higher mortality
  • COVID-19 in-hospital mortality was approximately 3X higher than for seasonal influenza
  • While COVID-19 patients did have significant rates of diabetes and obesity, patients with influenza were more likely to have significant comorbidities such as heart failure and COPD
  • Greater COVID-19 disease severity may be due to exaggerated immune response in COVID-19
• Caution advised regarding mortality rates in adolescent population due to small ‘n’
• The rate of COVID-19 hospitalizations in children is much lower than for influenza but associated with higher mortality

Learn More – Primary Sources:

Comparison of the characteristics, morbidity, and mortality of COVID-19 and seasonal influenza: a nationwide, population-based retrospective cohort study

Related ObG Topics:

How Do Clinical Characteristics of COVID-19 Infection Differ Between Symptomatic and Asymptomatic Patients?

Hyperinflammatory Shock in Children and COVID-19

CDC Weekly Update: Which Comorbidities are Associated with COVID-19 in the US?

Is Obesity an Independent Risk Factor for COVID-19 Related Mortality?