Background: The progression of coronavirus disease-2019 (COVID-19) is less well-studied in asymptomatic patients. The study aimed to understand the clinical characteristics of asymptomatic COVID-19 patients at the time of admission and follow-up their occurrence of symptoms during hospitalization.
Methods: Patients were divided into two groups—those with no symptoms until discharge (group A) and those who had symptoms that developed during hospitalization (group B). Baseline and clinical characteristics were retrospectively measured, and logistic regression analysis was performed to identify risk factors for deterioration during hospital stay.
Results: Overall, 223 patients were enrolled in the study, including 42 and 181 patients in groups A and B, respectively. Patients were older in group B than in group A. They developed cough as the most common symptom. Abnormal initial chest X-ray (CXR) and higher levels of C-reactive protein were frequently observed in group B than in group A. Moreover, 5 patients required mechanical support, including hi-flow nasal cannular and mechanical ventilation in group B. Five patients were transferred to tertiary hospitals owing to deterioration, and 4 patients succumbed to COVID-19. The risk factors for deterioration were age over 75 years, diabetes mellitus, and C-reactive protein > 1.
Conclusions: Even when the patients have no symptoms at admission, we recommend close monitoring of symptoms during hospital stay in patients who present with risk factors at the time of admission.