Sex Difference in Characteristics and Predictors of In-Hospital Mortality among Patients with COVID-19

Introduction: With a surge in the prevalence of coronavirus disease-2019 (COVID-19) in Beijing starting in October 2022, hospitalisation rates increased markedly. This study aimed to evaluate factors associated with in-hospital mortality in patients with COVID-19. Methods: Using data from hospitalised patients, sex-based differences in clinical characteristics, in-hospital management, and in-hospital mortality among patients diagnosed with COVID-19 were evaluated. Predictive factors associated with mortality in 1,091 patients admitted to the Beijing Anzhen Hospital (Beijing, China) for COVID-19 between October 2022 and January 2023 were also evaluated. Results: Data from 1,091 patients hospitalised with COVID-19 were included in the analysis. In-hospital mortality rates for male and female patients were 14.9% and 10.4%, respectively. Multifactorial logistic analysis indicated that lymphocyte percentage (LYM%) (odds ratio [OR] 0.863, 95% confidence interval [CI] 0.805-0.925; p < 0.001), uric acid (OR 1.004, 95% CI: 1.002-1.006; p = 0.001), and high-sensitivity C-reactive protein (OR 1.094, 95% CI: 1.012-1.183; p = 0.024) levels were independently associated with COVID-19-related in-hospital mortality. Among female patients, multifactorial analysis revealed that LYM% (OR 0.856, 95% CI: 0.796-0.920; p < 0.001), older age (OR 1.061, 95% CI: 1.020-1.103; p = 0.003), obesity (OR 2.590, 95% CI: 1.131-5.931; p = 0.024), and a high high-sensitivity troponin I level (OR 2.602, 95% CI: 1.157-5.853; p = 0.021) were risk factors for in-hospital mortality. Receiver operating characteristic (ROC) curve analysis, including area under the ROC curve, showed that the efficacy of LYM% in predicting in-hospital death was 0.800 (sensitivity, 63.2%; specificity, 83.2%) in male patients and 0.815 (sensitivity, 87.5%; specificity, 64.4%) in female patients. Conclusion: LYM% is a consistent predictor of in-hospital mortality for both sexes. Older age and markers of systemic inflammation, myocardial injury, and metabolic dysregulation are also associated with a high mortality risk. These findings may help identify patients who require closer monitoring and tailored interventions to improve outcomes.