Development and validation of an Occupational Hazards Index (OHI) and its association with hypertension-diabetes comorbidity in steel workers: a prospective cohort study
摘要
Steelworkers are exposed to complex occupational hazards; however, evidence regarding the joint effects of these hazards on hypertension-diabetes comorbidity (HDC) remains limited due to the absence of a comprehensive exposure assessment tool.
MethodsA prospective cohort study was conducted using data from the “Health Effect Cohort of Occupational Populations in the Beijing-Tianjin-Hebei Region”. A total of 5310 steelworkers without HDC at baseline (2017) were followed up until 2024. The Occupational Hazards Index (OHI) was constructed by integrating measured levels of 22 physical and chemical hazards (e.g., high temperature, noise, dust, carbon monoxide [CO], metals) using the Euclidean norm model, which is based on hazard quotients (measured concentration/Occupational Exposure Limit [OEL]). HDC was defined as the co-occurrence of hypertension and type 2 diabetes. Cox proportional hazards models were employed to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between the OHI (analyzed both as a continuous variable and categorized into high/low risk groups based on a restricted cubic spline-derived cut-off value of 102.75) and HDC risk, with adjustment for potential confounders.
ResultsDuring a median follow-up period of 72 months, 595 incident cases of HDC were identified, with a cumulative incidence of 11.2%. The OHI showed a right-skewed distribution (median: 102.76; interquartile range [IQR]: 79.38-132.38). A significant non-linear dose-response relationship was observed between OHI and HDC risk (P for overall association < 0.001, P for non-linearity < 0.001). After full adjustment for demographic characteristics, family history of chronic diseases, lifestyle factors, anthropometric measurements, and occupational factors, each one-unit increase in the OHI was associated with a 0.3% higher risk of HDC (HR = 1.003; 95% CI: 1.001–1.005). Workers in the high-risk OHI group (≥ 102.75) had a 30.8% higher risk of HDC compared to those in the low-risk group (HR = 1.308, 95% CI: 1.108–1.543). Stratified analyses suggested that the association might be more pronounced in males, individuals aged 40–49, current smokers, and those with unhealthy lifestyles (e.g., poor diet, obesity).
ConclusionWe developed a novel Occupational Hazards Index (OHI) that effectively quantifies combined occupational exposure. Our prospective findings indicate that higher OHI scores are significantly associated with an elevated risk of HDC among steel workers, highlighting the importance of comprehensive occupational hazard assessment for the primary prevention of this comorbidity.