Fig. 5

Subgroup and sensitivity analyses of ARG abundance in healthcare workers and health controls. A Subgroup analysis of ARG abundance compared healthcare workers (HW) and healthy population (HP) across different variables. Regression coefficients (β), 95% confidence intervals (CI), and p-values are displayed. Significant interaction effects are observed for age (p for interaction = 0.01) and BMI (p for interaction = 0.02), with higher age and BMI > 24 being associated with increased ARG abundance among healthcare workers compared to health controls. B Sensitivity analysis compared the abundance of ARG between healthcare workers from the Henan (HN) and Zhejiang (ZJ) provinces and health controls. Both Henan and Zhejiang healthcare workers exhibit significantly higher ARG abundance compared to health controls (fold change = 1.20, 95% CI: 1.16–1.46, p < 0.001 and fold change = 1.12, 95% CI: 1.07–1.30, p = 0.001, respectively, adjusted by age, gender, and BMI). C Sensitivity analysis compared ARG abundance between different medical professions and health controls. Nursing assistants have the highest ARG abundance (fold change = 1.33, 95% CI: 1.29–1.76, p < 0.001), followed by physicians (fold change = 1.18, 95% CI: 1.09–1.47, p = 0.002) and nurses (fold change = 1.08, 95% CI: 1.01–1.23, p = 0.03). BMI, age, and gender have been adjusted as covariates