Risk factors for severe COVID-19 in middle-aged patients without comorbidities: a multicentre retrospective study

摘要

The incidence of comorbidities in different age groups for all 441 patients with COVID-19. Comorbidities were defined as having at least one of the followings before diagnosis of COVID-19: hypertension, diabetes, coronary heart disease, stroke, hyperlipemia, bronchiectasis, asthma, chronic lung disease, chronic kidney disease, chronic liver disease, cancer, hematologic disease, autoimmune disease and HIV infection