Abstract:  The objective of this study was to assess the association between  patients' epidemiological characteristics and comorbidities with  SARS-CoV-2 infection severity and related mortality risk. An umbrella  systematic review, including a meta-analysis examining the association between patients' underlying conditions and severity (defined as need  for hospitalization) and mortality of COVID-19, was performed. Studies  were included if they reported pooled risk estimates of at least three  underlying determinants for hospitalization, critical disease (ICU  admission, mechanical ventilation), and hospital mortality in patients  diagnosed with SARS-CoV-2 infection. Evidence was summarized as pooled  odds ratios (pOR) for disease outcomes with 95% confidence intervals  (95% CI). Sixteen systematic reviews investigating the possible  associations of comorbidities with severity or death from COVID-19  disease were included. Hospitalization was associated with age >  60 years (pOR 3.50; 95% CI 2.97-4.36), smoking habit (pOR 3.50; 95% CI  2.97-4.36), and chronic pulmonary disease (pOR 2.94; 95% CI 2.14-4.04).  Chronic pulmonary disease (pOR 2.82; 95% CI 1.92-4.14), cerebrovascular  disease (pOR 2.74; 95% CI 1.59-4.74), and cardiovascular disease (pOR  2.44; 95% CI 1.97-3.01) were likely to be associated with increased risk  of critical COVID-19. The highest risk of mortality was associated with  cardiovascular disease (pOR 3.59; 95% CI 2.83-4.56), cerebrovascular  disease (pOR 3.11; 95% CI 2.35-4.11), and chronic renal disease (pOR  3.02; 95% CI 2.61-3.49). In conclusion, this umbrella systematic review  provides a comprehensive summary of meta-analyses examining the impact  of patients' characteristics on COVID-19 outcomes. Elderly patients and  those cardiovascular, cerebrovascular, and chronic renal disease should  be prioritized for pre-exposure and post-exposure prophylaxis and early  treatment.

Keywords: COVID-19; SARS-CoV-2; comorbidities; meta-analysis; mortality; predictors; severe disease.