The Association between Presence of Comorbidities and COVID-19 Severity: A Systematic Review and Meta-Analysis

Aim: Several studies reported the accompaniment of severe COVID-19 with comorbidities. However, there is not a systematic evaluation of all aspects of this association. Therefore, this meta-analysis aimed to assess the association between all underlying comorbidities in COVID-19 infection severity. Methods: Electronic literature search was performed via scientific search engines. After the removal of duplicates and selection of articles of interest, 28 studies were included. A fixed-effects model was used; however, if heterogeneity was high ( I 2 > 50%) a random-effects model was applied to combine the data. Results: A total of 6,270 individuals were assessed (1,615 severe and 4,655 non-severe patients). The median age was 63 (95% confidence interval [CI]: 49–74) and 47 (95% CI: 19–63) years in the severe and non-severe groups, respectively. Moreover, about 41% of patients had comorbidities. Severity was higher in patients with a history of cerebrovascular disease: OR 4.85 (95% CI: 3.11–7.57). The odds of being in a severe group increase by 4.81 (95% CI: 3.43–6.74) for a history of cardiovascular disease (CVD). This was 4.19 (95% CI: 2.84–6.19) for chronic lung disease and 3.18, 95% CI: 2.09–4.82 for cancer. The odds ratios of diabetes and hypertension were 2.61 (95% CI: 2.02–3.3) and 2.37 (95% CI: 1.80–3.13), respectively. Conclusions: The presence of comorbidities is associated with severity of COVID-19 infection. The strongest association was observed for cerebrovascular disease, followed by CVD, chronic lung disease, cancer, diabetes, and hypertension.