Exploration of severe Covid-19 associated risk factor in China: meta-analysis of current evidence

Methods: We systemically and comprehensively retrieved the eligible study evaluating clinical difference between severe versus non-severe Covid-19. Main effect sizes were demography characteristics, comorbidities, signs and symptoms, laboratory findings as well as radiological features in chest CT. Results: 14 studies with a total of 2,566 individuals (771 in Severe group and 1,795 in Non-severe group) were eligible for this meta-analysis. It was demonstrated that older and male person was more susceptible to severe Covid-19. Patients with underlying comorbidity, such as hypertension, diabetes, heart disease and COPD were associated with significantly increased susceptibility of severe Covid-19. Patients with dyspnea were more likely to be severe illness. Depressed total lymphocytes were observed in this article. Meanwhile, although reticulation (30.8%), intrathoracic lymph node enlargement (56.4%) and pleural effusions (30.8%) were relatively rarely seen, meta-analysis revealed that patients with these presentations in chest CT were associated with increased risks of severe Covid-19. Conclusions: There are significant differences in clinical characteristic between the severe and non-severe Covid-19 patients. Many factors are related to the severity of the disease, which can help clinicians to differentiate severe patient from non-severe patient.