The influence of comorbidity on the severity of COVID-19 disease: systematic review and analysis

BackgroundA novel form of coronavirus disease (SARS-CoV-2) has spread rapidly across the world. What risk factors influence the severity of the disease is of considerable importance. AimThis research offers a systematic review and meta-analysis of the correlation between common clinical conditions and comorbidities and the severity of COVID-19. MethodologyTwo independent researchers searched Europe PMC, Google Scholar, and PubMed databases for articles related to influence comorbidities have on the progress of the disease. A search engine was also created to screen a further 59,000 articles in COVID-19 Open Research Dataset (CORD-19). Random-effects modeling was used to pool 95% confidence intervals (CIs) and odds ratios (ORs). The significance of all comorbidities and clinical conditions to the severity of the disease was evaluated by employing machine-learning techniques. Publication bias was assessed by using funnel-plots and Egger's test. Heterogeneity was tested using I2. ResultsThe meta-analysis incorporated 12 studies spanning 4,101 confirmed COVID-19 patients who were admitted to Chinese hospitals. The prevalence of the most commonly associated co-morbidities and their corresponding odds ratio for disease severity were as follows: coronary heart disease (OR 2.97 [CI: 1.99-4.45], p < 0.0001), cancer (OR 2.65 [CI: 1.12-6.29], p < 0.03), cardiovascular disease (OR 2.89 [CI: 1.90-4.40], p < 0.0001), COPD (OR 3.24 [CI: 1.66-6.32], p = 0.0), and kidney disease (OR 2.2.4 [CI: 1.01-4.99], p = 0.05) with low or moderate level of heterogeneity. The most frequently exhibited clinical symptoms were fever (OR 1.37 [CI: 1.01-1.86], p = 0.04), myalgia/fatigue (OR 1.31 [CI: 1.11-1.55], p = 0.0018), and dyspnea (OR 3.61, [CI: 2.57-5.06], p = <0.0001). No significant associations between disease severity and liver disease, smoking habits, and other clinical conditions, such as a cough, respiratory/ARDS, diarrhea or chest tightness/pain were found. The meta-analysis also revealed that the incubation period was positively associated with disease severity. ConclusionExisting comorbidities, including COPD, cardiovascular disease, and coronary heart disease, increase the severity of COVID-19. Some studies found a statistically significant association between comorbidities such as diabetes and hypertension and disease severity. However, these studies may be biased due to substantial heterogeneity.