Age-related Risk Factors and Severity of SARS-CoV-2 Infection: a systematic review and meta-analysis


COVID-19 pandemic
Symptoms and Comorbidities
Systematic Review
Correlation Analysis


Objectives: We aimed to estimate the reported symptoms and comorbidities and assess the correlation between a series of symptoms and comorbidities and age of the patients’ positive in COVID-19.

Methods: We performed a systematic review and meta-analysis [PROSPERO registration: CRD42020182677]. Databases [PubMed, SCOPUS, EMBASE, WHO, Semantic Scholar, and COVID-19 Primer] were searched for clinical studies published from January to April 2020. The pooled prevalence of symptoms and comorbidities were identified using the random effect model, and the multivariable factor analysis was performed to show the correlation between a group of symptoms and comorbidities and age of the COVID-19 patients.

Results: Twenty-nine articles, with 4,884 COVID-19 patients were included in this study.  Altogether, we found 33 symptoms and 44 comorbidities where the most frequent 19 symptoms and 11 comorbidities were included in the meta-analysis. The fever [84%], cough/dry cough [61%], and fatigue/weakness [42%] were found more prevalent. On the other hand, acute respiratory distress syndrome, hypertension and diabetes were the most prevalent comorbid condition. The multivariable factor analysis showed positive association between a group of symptoms and comorbidities, and with the patients' age. The symptoms comprising fever, dyspnea/shortness of breath, nausea, vomiting, abdominal pain, dizziness, anorexia and pharyngalgia; and the comorbidities including diabetes, hypertension, coronary heart disease, COPD/lung disease and ARDS were positively correlated with the COVID-19 patient’s age.

Conclusion: As a unique effort, this study found a group of symptoms and comorbidities, correlated with age of the COVID-19 patients that may help to implement patient-centred interventions.


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