Kanwal Khalid, Amr Adel Ahmed Abd El-Aal, Michelle Felicia Lee
Although numerous studies have investigated the association between hypertension and coronavirus disease 2019 (COVID-19) severity, differences in study characteristics have limited the consistency and generalizability of the available evidence. This systematic review and meta-analysis systematically evaluated the association between hypertension and COVID-19 severity by synthesizing evidence from 30 studies involving 15,549 participants comparing the prevalence of hypertension in non-severe and severe COVID-19 patients. Pooled odds ratios (ORs) were calculated using a random-effects model. Heterogeneity was assessed using I² and τ² statistics, while subgroup analyses and meta-regression examined the effects of region, sample size, study quality, age, and gender. Publication bias was evaluated using funnel plots and Egger's test. Hypertension was more frequently observed in severe COVID-19 cases across the included studies with a pooled odds ratio (OR) of 2.73 (95% CI: 1.85-4.02, p < 0.00001), However, substantial heterogeneity was observed (I² = 88%), limiting the precision of the pooled estimate. Subgroup analysis showed that sample size, NOS scores, and age did not significantly explain heterogeneity, with gender composition also not significantly associated with effect size (β = 0.021, p = 0.38). Funnel plot analysis and Egger's test showed no significant publication bias. Overall, hypertension was associated with an increased likelihood of severe COVID-19, although the high level of heterogeneity suggests that the findings should be interpreted with caution. These findings contribute to the understanding of the association between hypertension and COVID-19 severity and may inform clinical risk stratification and public health decision-making.