In sensitivity analyses, the association between occupational noise exposure and the risk of hypertension persisted for both the high-exposure (adjusted RR=1.95, 95% CI: 1.16, 3.28) and the intermediate-exposure (adjusted RR=1.74, 95% CI: 1.08, 2.80) groups after the addition of the 2 variables of salt intake and family history of hypertension to model 3. Furthermore, an increasing exposure-response trend was found (adjusted RR=1.37, 95% CI: 1.07, 1.75) (P=0.014) in this sensitivity analysis. No significant differences were found among the 3 exposure groups with regard to salt intake (P=0.173) or family history of hypertension (P=0.656).