Clinical epidemiological characteristics of Omicron variant BA.2 infection in patients with hypertension

Hypertension is the most frequent comorbidity in COVID-19 patients. However, the clinical manifestations and prognostic predictors for hypertensive patients infected with the Omicron variant remain controversial. In this study, we investigate the clinical epidemiological characteristics and prognostic risk factors of hypertensive patients infected with the SARS-CoV-2 Omicron BA.2 variant. We retrospectively collected and analyzed the demographic and clinical characteristics of 4173 Omicron variant BA.2 cases admitted to Shanghai Pudong Hospital from April to June 2022. Multivariable logistic regression was used to identify independent predictors of disease severity and fatal outcomes among COVID-19 patients with comorbid hypertension. Among the 4173 cases, 934 (22.38%) were diagnosed with hypertension. The majority of these patients (86.7%) presented as asymptomatic or mild cases, while 32 patients (3.4%) died. Multivariable analysis for clinical classification showed that COVID-19 vaccination (OR = 0.280, 95% CI:0.143–0.548) and higher lymphocyte count (OR = 0.608, 95% CI:0.411–0.898) were protective factors, whereas pulmonary infection (OR = 5.422, 95% CI:2.789–10.542) and elevated hs-CRP (OR = 1.006, 95% CI: 1.001–1.011) were independently associated with increased risk of moderate or severe disease (all P < 0.05). For mortality, chronic kidney failure (OR = 5.701, 95% CI: 1.638–19.842), theophylline treatment (OR = 5.063, 95% CI: 1.818–14.101), and elevated D-dimer (OR = 1.092, 95% CI: 1.002–1.190) were identified as independent risk factors, while higher lymphocyte proportion (OR = 0.920, 95% CI: 0.865–0.977) and higher albumin (OR = 0.865, 95% CI: 0.793–0.944) were protective factors (all P < 0.05). Notably, all 32 fatal cases were unvaccinated and 71.9% had more than one underlying disease. Although most hypertensive patients infected with Omicron BA.2 exhibit asymptomatic or mild symptoms, highly vulnerable subgroups—particularly those with chronic kidney failure, low lymphocyte proportion, hypoalbuminemia, and elevated inflammatory markers—face significantly elevated risks of severe illness and death. Therefore, continuous monitoring of systemic inflammatory markers (e.g., hs-CRP, D-dimer) and immune-nutritional indicators (e.g., lymphocyte count, albumin) in these vulnerable populations is essential to preempt sudden and fatal clinical deterioration. Not applicable.