Hospitalised versus outpatient COVID-19 patients' background characteristics and comorbidities: A systematic review and meta-analysis.

This study aimed to systematically assess COVID-19 patient background characteristics and pre-existing comorbidities associated with hospitalisation status. The meta-analysis included cross-sectional, cohort, and case-series studies with information on hospitalisation versus outpatient status for COVID-19 patients, with background characteristics and pre-existing comorbidities. A total of 1,002,006 patients from 40 studies were identified. Significantly higher odds of hospitalisation were observed in Black individuals (OR = 1.33, 95% CI: 1.04-1.70), males (OR = 1.59, 95% CI: 1.43-1.76), and persons with current/past smoking (OR = 1.59, 95% CI: 1.34-1.88). Additionally, individuals with pre-existing comorbidities were more likely to be hospitalised [asthma (OR = 1.22, 95% CI: 1.02-1.45), COPD (OR = 3.68, 95% CI: 2.97-4.55), congestive heart failure (OR = 6.80, 95% CI: 4.97-9.31), coronary heart disease (OR = 4.40, 95% CI: 3.15-6.16), diabetes (OR = 3.90, 95% CI: 3.29-4.63), hypertension (OR = 3.89, 95% CI: 3.34-4.54), obesity (OR = 1.98, 95% CI: 1.59-2.46) and renal chronic disease (OR = 5.84, 95% CI: 4.51-7.56)]. High heterogeneity and low publication bias among all factors were found. Age was not included due to the large variability in the estimates reported. In this systematic review/meta-analysis for patients with COVID-19, Black patients, males, persons who smoke, and those with pre-existing comorbidities were more likely to be hospitalised than their counterparts. Findings provide evidence of populations with higher odds of hospitalisation for COVID-19.