Risk Factors and Mortality for Atypical Presentation of COVID-19 Infection in Hospitalized Patients - Lessons From the Early Pandemic.

Objective: To assess the clinical epidemiology and outcomes of patients hospitalized with COVID-19 who did not experience fever and cough during the early pandemic.

Methods: Retrospective cohort of all patients admitted during March 13, 2020 through May 13, 2020 with laboratory-confirmed COVID-19 to 3 tertiary-care hospitals. Patient-level data (demographic, clinical manifestations, comorbid illnesses, inpatient treatment) were analyzed. The main outcome variable was atypical presentation, defined as any hospitalized patient with COVID-19 infection who did not experience both fever and cough. We identified risk factors for atypical presentation on univariate and multivariate analyses and assessed 30-day mortality differences via survival analysis.

Results: Of 163 patients in the study, 39 (24%) were atypical. On univariate analysis, atypical cases were significantly more likely to be older, reside in a long-term-care facility (LTCF), and have underlying diabetes mellitus, stroke, or cardiac disease; present without dyspnea or myalgia, have lower C-reactive proteins (CRP) and higher beta-natriuretic peptides. They were less likely to receive intensive care unit care or specific COVID-19 treatments ( < .05). The incidence of acute respiratory failure was not significantly different between the groups. On logistic regression, atypical cases were significantly more likely to be LTCF residents (  = 0.003) and have a lower average CRP (  = 0.01). Atypical cases had significantly higher 30-day mortality (hazard ratio 3.4 [95% CI, 1.6 - 7.2],   = 0.002).

Conclusion: During the first pandemic surge, COVID-19 patients without inflammatory signs and symptoms were more likely to be LTCF residents and had higher mortality. Timely recognition of these atypical presentations may have prevented spread and improved clinical outcomes.