Comorbidities and the risk of severe or fatal outcomes associated with coronavirus disease 2019: A systematic review and meta-analysis

•Among patients with severe or fatal coronavirus disease 2019 (COVID-19), the most prevalent comorbidities were obesity and hypertension, followed by diabetes, cardiovascular disease, respiratory disease, cerebrovascular disease, malignancy, chronic kidney disease, and liver disease.•Comorbid respiratory disease was identified as the strongest risk factor for COVID-19 severity, followed by hypertension, cardiovascular disease, chronic kidney disease, cerebrovascular disease, malignancy, diabetes, and obesity.•Subgroup analyses were conducted according to severe clinical outcomes and country of residence in the study population.•Knowledge of these risk factors could help clinicians better identify and manage the high-risk populations.