The novel coronavirus (SARS-CoV-2, causing COVID-19) was originally isolated in Wuhan, China. This virus spread quickly throughout many countries in Asia and now Europe, Australia, North America, leading the World Health Organization to declare COVID-19 a pandemic. Given the rapid spread of cases, the authors sought to provide analysis of patients with COVID-19, their clinical characteristics, and severity of disease.
This was a retrospective review of Chinese medical records for laboratory-confirmed COVID-19 reported to the National Health Commission between December 11, 2019 to January 29, 2020. Electronic medical records were used to record various clinical data including exposure risk, signs and symptoms, laboratory findings, and radiologic findings. Several researchers performed chart abstraction and disagreements were made by a third reviewer. If radiologic findings were included, these were reviewed by respiratory medicine attending physicians who interpreted the findings. Incubation periods of less than 1 day were excluded. Fever was defined as an axillary temperature of 37.5 degrees Celsius or higher. Patients were categorized into severe or nonsevere based on the American Thoracic Society guidelines for community acquired pneumonia. The primary composite endpoint was admission to the intensive care unit (ICU), use of mechanical ventilation, or death. Secondary outcomes included death rates from symptom onset until each component of the composite end-point.
There were 7736 patients admitted at 552 sites during the study period and data were obtained on 1099 patients (14.2%). The majority were nonsevere disease (926, 84.3%). The median age was 47 years (IQR 35-58), 41.9% were female, and most were nonsmokers (85.4%). Any comorbidity was recorded in 23.7% of patients, with hypertension being the most common (15.0%). The majority of patients (72.3%) had recent contact with a Wuhan resident, although 25.9% had no reported exposure. The median incubation period was 4.0 days (IQR 2.0-7.0). Regarding symptoms, only 43.8% of patients had fever on presentation but 88.7% developed fever during hospitalization. Besides fever, the most common symptoms overall were cough (67.8%), fatigue (38.1%), sputum production (33.7%), and shortness of breath (18.7%). Chest radiograph findings were available for 274 patients, with the majority being abnormal (59.1%). Findings included bilateral patchy shadowing (36.5%), local patchy shadowing (28.1%), ground-glass opacity (20.1%), and interstitial abnormality (4.4%). Chest CT results were available on 975 patients. The majority (86.2%) were abnormal and consisted of ground-glass opacity (56.4%), bilateral patchy shadowing (51.8%), local patchy shadowing (41.9%), and interstitial abnormalities (14.7%). Laboratory testing was available on most, depending on the test, and showed a median white blood cell count of 4700/mm3 (IQR 3500-6000), elevated C-reactive protein (>10mg/L in 60.7%), and normal procalcitonin (<0.5ng/mL in 94.5%). Other notable laboratory abnormalities included elevated D-dimer (> 0.5mg/L in 46.4%) and elevated LDH (>250U/L in 41%). The most common complications were pneumonia (91.1%) followed by acute respiratory distress syndrome (3.4%) and most common treatments were intravenous antibiotics (58.0%), oxygen therapy (41.3%), and oseltamivir (35.8%). Systemic glucocorticoids and immune globulin were less common therapies, and mechanical ventilation was needed in only 6.1%. At the conclusion of the study, 15 (1.4%) of patients had died and 55 (5.0%) had been discharged fro the hospital. The majority of the remaining patients were still hospitalized. Regarding the composite endpoint, there were 67 patients (6.1%) with ICU admission, mechanical ventilation, or death, leading to a cumulative risk of 3.6%. This percentage increased if you were designated as severe disease; in this case 24.9% had the composite outcome, leading to a cumulative risk of 20.6%.
The authors concluded that presenting symptoms and workup can be variable, with many patients being afebrile and having normal radiologic studies. Several limitations were noted including missing data for many on incubation periods. Additionally the majority of the patients were still hospitalized at the end of the study and therefore outcomes could not be provided for those patients.
Comment: While this study provides helpful clinical information to assist emergency physicians in identifying potential COVID-19 patients, we must understand the limitations. Most significantly, this was only a very small portion of the overall sample size of confirmed COVID-19 patients. Additionally, be cautious in directly applying these results to patients in the United States as populations may differ.