Suleyman G, Fadel R, Alsaadi A, Sueng LN, Ghandour A, Alkhatib A, Singh T, Parsons A, Miller J, Ramesh M, Brar I, and Alangaden G. Progression to Critical Illness and Death in Patients With Breakthrough Hospitalizations. Open Forum Infect Dis 2022; 9(7):ofac213.
Open Forum Infect Dis
Background: Characterization of disease progression and outcomes after coronavirus disease 2019 (COVID-19)-related hospitalization in vaccinated compared with unvaccinated individuals is limited.
Methods: This was a retrospective case-control study of symptomatic vaccinated (cases) and unvaccinated (controls) participants hospitalized for COVID-19 between December 30, 2020, and September 30, 2021, in Southeast Michigan. Hospitalized adult patients with lab-confirmed COVID-19 were identified through daily census report. Breakthrough infection was defined as detection of severe acute respiratory syndrome coronavirus 2 ≥14 days after completion of the primary vaccination series. The association between prior vaccination and critical COVID-19 illness (composite of intensive care unit [ICU] admission, invasive mechanical ventilation [IMV], 28-day mortality) was examined.
Results: Two hundred ten (39%) fully vaccinated and 325 (61%) unvaccinated patients were evaluated. Compared with controls, cases were older, had more comorbidities (4 [3-7] vs 2 [1-4]; P < .001), and were more likely to be immunocompromised. Cases had less severe symptoms compared with controls (2 [1-2] vs 2 [2-3]; P < .001) and were less likely to progress to critical COVID-19 illness (33.3% vs 45.5%; P < .001); 28-day mortality was significantly lower in cases (11.0% vs 24.9%; P < .001). Symptom severity (odds ratio [OR], 2.59; 95% CI, 1.61-4.16; P < .001) and modified Sequential Organ Failure Assessment score on presentation (OR, 1.74; 95% CI, 1.48-2.06; P < .001) were independently associated with development of critical COVID-19 illness. Prior vaccination (OR, 0.528; 95% CI, 0.307-0.910; P = .020) was protective.
Conclusions: COVID-19-vaccinated patients were less likely to develop critical COVID-19 illness and more likely to survive. Disease severity at presentation was a predictor of adverse outcomes regardless of vaccination status.