Objective To examine the prevalence of hypertension and abnormal electrocardiogram (ECG) among the noise-exposed population in Songjiang District, Shanghai, and to analyze the influencing factors for hypertension and abnormal ECG.

Methods Occupational health examination data, encompassing basic demographic information, physical examinations, audiometric testing, blood pressure measurements, and ECG assessments, were collected from 20 165 noise-exposed workers across all manufacturing enterprise in Songjiang District in 2024. Hypertension and abnormal ECG findings were identified as indicators of health impairment. Categorical data were presented as frequencies and percentages (%). Univariate chi-square tests and multivariate logistic regression analyses were employed to identify factors associated with hypertension and abnormal ECG outcomes.

Results The detection rates of hypertension and abnormal ECG among noise-exposed workers in the manufacturing industry in Songjiang District were 22.78% and 13.06%, respectively. Across different enterprise scales, industry categories and economic types, micro-sized enterprises (26.90%, 25.29%), furniture manufacturing enterprises (31.01%, 31.28%) and domestic-funded enterprises (23.43%, 15.57%) had the highest detection rates of hypertension and abnormal ECG. The detection rates of hypertension and abnormal ECG were relatively high among male workers, those aged ≥60 years old and those with a Body Mass Index(BMI) ≥24.0 kg·m^-2. The detection rates of hypertension and abnormal ECG in workers exposed to noise combined with other hazards such as heat stress (27.47%, 16.87%) and benzene (22.22%, 23.46%) were higher than those exposed to noise alone (21.40%, 11.60%) (P<0.01). Compared to workers in the general equipment manufacturing industry, those in the automotive manufacturing industry had a higher risk of hypertension (OR=1.284, 95%CI: 1.098‒1.501), and those in the furniture manufacturing industry had a higher risk of abnormal ECG (OR=2.615, 95%CI: 2.014‒3.385). Micro and small enterprises, BMI ≥24.0 kg·m^-2 and advanced age had potential associations with hypertension and abnormal ECG. In addition, compared to the group exposed to noise alone, the group with noise and other physical hazards had a higher risk of hypertension (OR=1.146, 95%CI: 1.071‒1.288) and abnormal ECG (OR=1.179, 95%CI: 1.072‒1.297). Compared to the normal group, the risks of hypertension and abnormal ECG in workers with abnormal high-frequency hearing threshold for both ears increased by 21.5% (OR=1.215, 95%CI: 1.082‒1.364) and 21.0% (OR=1.210, 95%CI: 1.006‒1.410), respectively.

Conclusion Different types of employers (economic type, industry category, enterprise size) and individual characteristics of workers (gender, age, length of service, BMI, exposure to other physical hazards, and abnormal high-frequency hearing threshold in both ears) impacted the association between noise exposure and hypertension/ECG abnormalities. Employers should enhance the management of occupational noise. In addition to hearing impairment, attention should be paid to abnormal changes in blood pressure and ECG of workers, and corresponding intervention measures should be implemented to reduce the occurrence and development of cardiovascular diseases among workers exposed to noise.