Clinical characteristics and durations of hospitalized patients with COVID-19 in Beijing: a retrospective cohort study

Zhao, Wen; Yu, Shikai; Zha, Xiangyi; Wang, Ning; Pang, Qiumei; Li, Tongzeng; Li, Aixin

Background: COVID-19 is still becoming an increasing global threat to public health. More detailed and specific characteristics of COVID-19 are needed to better understand this disease. Additionally, durations of COVID-19, e.g., the average time from exposure to recovery, which is of great value in understanding this disease, has not been reported so far. Aims: To give the information on clinical characteristics and different durations of COVID-19 and to identify the potential risk factors for longer hospitalization duration. Methods: In this retrospective study, we enrolled 77 patients (mean age: 52 years; 44.2% males) with laboratory-confirmed COVID-19 admitted to Beijing YouAn Hospital during 21st Jan and 8th February 2020. Epidemiological, clinical and radiological data on admission were collected; complications and outcomes were followed up until 29th February 2020. The study endpoint was the discharge within two weeks. Cox proportional-hazards regression was performed to identify risk factors for longer hospitalization duration. Results: Of 77 patients, there are 34 (44.2%) males, 24 (31.2%) with comorbidities, 22 (28.6%) lymphopenia, 20 (26.0%) categorized as severe patients, and 28 (36.4%) occurred complications. By the end of follow-up, 64 (83.1%) patients were discharged home after being tested negative for SARS-CoV-2 infections, 8 remained in hospital and 5 died. 36 (46.8%) patients were discharged within 14 days and thus reached the study endpoint, including 34 (59.6%) of 57 non-severe patients and 2 (10%) of 20 severe patients. The overall cumulative probability of the endpoint was 48.3%. Hospital length of stay and duration of exposure to discharge for 64 discharged patients were 13 (10-16.5) and 23 (18-24.5) days, respectively. Multivariable stepwise Cox regression model showed bilateral pneumonia on CT scan, shorter time from the illness onset to admission, the severity of disease and lymphopenia were independently associated with longer hospitalized duration. Conclusions: COVID-19 has significantly shorter duration of disease and hospital length of stay than SARS. Bilateral pneumonia on CT scan, shorter period of illness onset to admission, lymphopenia, the severity of disease are the risk factors for longer hospitalization duration of COVID-19.