More Clinical Events Occur in COVID-19 Pneumonia vs Other Viral Pneumonias

SARS-CoV-2 viral pneumonia (PNA) may be associated with a higher incidence of clinical events than H3N2/H1N1 viral PNA, and race/ethnicity does not affect PNA inpatient mortality outcomes, according to study findings published in Heart & Lung.

Viral PNA, a serious complication of SARS-CoV-2, places patients at increased risk of coagulation abnormalities leading to thrombotic events, multi-organ failure, and death.

Investigators sought to compare thrombotic and clinical trends, death rates, and patient characteristics in SARS-CoV-2 PNA vs H3N2/H1N1 PNA.

The investigators conducted a single-center, retrospective, nonrandomized cohort study using electronic medical records of 257 adult patients (54% women; 46% Hispanic, 44% non-Hispanic Black) with primary diagnosis of SARS-CoV-2 PNA (mean [SD] age, 58 [15] years) or other viral (H3N2/H1N1) PNA (mean age, 63 [17] years). Participants were patients admitted to the University of Illinois Hospital and Health Sciences System (UIHHSS), an urban medical center with primarily Hispanic and Black non-Hispanic population, from October 2017 through August 2020. The SARS-CoV-2 cohort included 199 patients from the first wave of COVID-19 patients, and the viral PNA cohort included 58 patients with H1N1 or H3N2 PNA from 3 influenza seasons.

All participants had a primary diagnosis of viral PNA based on ICD-10 codes and positive molecular pathology results indicating SARS-CoV-2, H1N1, or H3N2 infection. The primary study endpoint was the composite incident rates of thrombotic complications (including deep vein thrombosis, ischemic stroke, arterial thromboembolism-myocardial infarction, venous thromboembolism-pulmonary embolism), major bleeding, renal replacement therapy, mechanical ventilation, infection, intensive care unit (ICU) admission, and death. Secondary outcomes were risk of mortality according to age, COVID-19 status, gender, race/ethnicity, obesity status, and anticoagulation compliance level, as assessed through multivariable logistic regression analyses.

Investigators found patients in the SARS-CoV-2 PNA cohort vs H3N2/H1N1 PNA cohort experienced similar hospital lengths of stay, but spent more days in the ICU (median 10 days vs 4 days, respectively; P =.056). Both the SARS-CoV-2 PNA and H3N2/H1N1 PNA cohorts were in high compliance with pharmacologic (89% vs 83%, respectively) and mechanical (91% vs 90%, respectively) thromboprophylaxis regimens.

By race/ethnicity, patients in the SARS-CoV-2 PNA cohort were 53% Hispanic, 39% non-Hispanic Black, and 6% White, whereas patients in the H3N2/H1N1 PNA cohort were 24% Hispanic, 60% non-Hispanic Black, and 10% White. With respect to comorbidities, patients in the SARS-CoV-2 PNA cohort included 55% who were obese and 19% who were morbidly obese; 58% with hypertension; and 40% with diabetes. Patients in the H3N2/H1N1 PNA cohort included 36% who were obese and 12% who were morbidly obese; 60% with hypertension; and 45% with diabetes.  

Investigators found no significant between-group difference in the composite primary endpoint. However, there were some notable between-group differences affecting the secondary study’s endpoints: (1) only patients in the ICU with SARS-CoV-2 PNA experienced thrombotic events (3%); (2) the SARS-CoV-2 PNA group vs H3N2/H1N1 PNA group had significantly higher incidence of mortality (15.6% vs 3.4%; P =.048) and renal replacement therapy (8.5% vs 0.0%; P =.016); and (3) longer durations of mechanical therapy were required by the SARS-CoV-2 PNA group. Adjusted odds ratios (aORs) showed a significant association between the risk of in-hospital mortality with age (aOR, 1.07), presence of SARS-CoV-2 (aOR, 11.37), and ICU admission (aOR, 41.95). The investigators found no significant association between ethnicity or race with risk of in-hospital mortality.

Study limitations include underpowered sample size; a relatively short study period; the fact that there have been widespread vaccinations since the study was concluded; the potential for inconsistent definition of race/ethnicity; and lack of resources and staff required to confirm thrombotic event diagnoses, which likely contributed to the observed low rates of thrombotic complications.

“SARS-CoV-2 PNA may lead to higher incidence of clinical events than those observed in H3N2/H1N1 viral pneumonia,” noted investigators, adding that results also indicated “that race/ethnicity does not drive mortality outcomes,” and that the incidence of thrombotic events was low and all occurred in the SARS-CoV-2 PNA group.

Disclosure: One study author declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.

This article originally appeared on Pulmonology Advisor