Objective:To investigate the prevalence of pre-diabetes mellitus (PDM) and the impact of occupation-related factors on PDM, among workers from a steel company in Tangshan city, Hebei province.Methods:Clustering sampling method was used to select a steel company and to carry out occupational health-related physical checkup programs for eligible workers who had working in this company for longer than one year. The study began in February and ended up in June, 2017. Workers who were with FPG level as ≤6.9 mmol/L, and free from diabetes, were selected as the subjects for this study. Questionnaires were used and physical examinations and FPG testing conducted.Results:The total number of subjects in this study was 4 173, of which 2 648 appeared as pre-diabetic, with the prevalence rate as 63.4 %. Increase of the PDM prevalence was in parallel with the length of service, among the workers. The risk for the pre-diabetes in those who worked more than 8 hours per day was 1.696 times higher than those who worked less than or equal to 8 h/d (95 %CI:1.517-1.937). Compared with those workers without exposures to heat, noise or carbon monoxides, the proportion of pre-diabetes appeared higher in workers exposed to heat, noise or CO with OR=1.782 (95 %CI: 1.205-2.636), 1.815 (95 %CI: 1.209-2.794) and 1.653 (95 %CI: 1.158-2.361), respectively. Risks for those who were exposed to heat or noise were higher than those who were free from exposure to any occupational hazards ( OR=2.098, 95 %CI: 1.296-3.397). Prevalence rates of pre-diabetes in those who were exposed to heat, noise or CO, were higher than that those who were not. Conclusion:Working hours and exposures to heat, noise or CO appeared as influential factors on PDM.

Objective:To investigate the effect of occupational factor exposures on carotid atherosclerosis (CAS) in steel workers.Methods:A frequency matched case-control study was conducted by age and factory proportion. A total of 1 033 workers with carotid atherosclerosis diagnosed by ultrasonography examination from February to June 2017 were selected as case group, and 1 033 workers without carotid atherosclerosis indicated by physical examination at the same time were selected as control group. The basic information of the workers, such as diet pattern, lifestyle, serum biochemical index and occupation history, were collected. The effects of occupational hazards on carotid atherosclerosis were analyzed by univariate and multivariate logistic regression analyses. The combined effects of various occupational hazards on carotid atherosclerosis were evaluated by environmental risk score (ERS).Results:High temperature, noise, occupational stress and night shift days increased the risk of CAS. With the increase of cumulative high temperature and noise exposure, occupational stress and night shift days, the risk of CAS increased (trend text: χ2=37.53, P<0.01; χ2=16.98, P<0.01; χ2=13.93, P<0.01; χ2=5.59, P<0.05). After adjustment of covariates, compared with P 20 group, the risk of carotid artery in P 40, P 60, P 80 and P 100 groups were as follows: high temperature 1.61 (1.19-2.18), 1.69 (1.25-2.30), 1.84 (1.36-2.49), 2.43 (1.77-3.34); noise 1.70 (1.15-2.52), 1.68 (1.20-2.35), 1.80 (1.34-2.42), 2.23 (1.53-3.26); occupational stress 1.39 (1.04- 1.86), 1.41 (1.06-1.89), 1.45(1.09-1.95), 1.48 (1.10-1.98); night shift days 1.58 (1.08-2.33), 1.66 (1.12-2.47), 1.55 (1.04-2.31), 1.76 (1.17-2.64). The results of the environmental risk score showed that the risk of carotid atherosclerosis increased with the increase of ERS (ERS trend text χ2=51.61, P<0.01); RCS results showed that there was a linear relationship between ERS and CAS in steel workers( P<0.01). Linear dose-response relationship existed between ERS and CAS (nonlinear test P>0.05). Conclusions:High temperature, noise, occupational stress and night shift days were related to carotid atherosclerosis. Linear dose-response relationship existed between ERS and CAS in steel workers.

OBJECTIVE: To explore the effects of cumulative noise exposure(CNE) on the intima-media thickness(IMT) of carotid artery in steel workers. METHODS: A cluster random sampling method was used to select 1 437 noise exposed workers in a steel company as study subjects. The CNE was calculated according to the noise intensity of the workplace, and the occupational health check was carried out to construct the structural equation model of noise to IMT. RESULTS: The detection rate of carotid atherosclerosis(CAS) in these 1 437 subjects was 38.3%. The CAS detection rates of steel workers increased with the increasing CNE(P<0.01). The structural equation model had good fitting effect. Path analysis showed CNE can indirectly affect IMT through blood pressure, triglycerides, fasting blood glucose, homocysteine, high-density lipoprotein & apolipoprotein A, low-density lipoprotein & apolipoprotein B. The total effects were-0.375, 0.337, 0.248, 0.117, 0.056, 0.056 and 0.018 respectively. CONCLUSION: CNE can indirectly increase the IMT of steel workers by acting on the proximal cause.

OBJECTIVE: To explore the effect of occupational high temperature exposure on type 2 diabetes( T2 DM) in male steel workers. METHODS: A cluster random sampling method was used to select 684 male steel workers,who exposed to occupational high temperature in a steel enterprise in Tangshan City,as the high temperature group,and 1 153 male steel workers without occupational high temperature exposure as the control group. The high temperature level of workers in these two groups was measured. The cumulative exposure( CE) of high temperature was calculated,and occupational health exam was performed. The multivariate logistic regression analysis and restricted cubic splines were used to analyze the relationship between high temperature CE and T2 DM. RESULTS: The prevalence of T2 DM in high-temperature group was higher than that in the control group( 13. 0% vs 7. 9%,P < 0. 05). The multivariate logistic regression analysis results showed that the risk of T2 DM in the high temperature group was higher than that in the control group after adjusting for age,body mass index,smoking,drinking,physical exercise and parents with diabetes( P < 0. 05). The 95% confidence interval was 1. 65( 1. 17-2. 33). Restricted cubic spline analysis showed that the high temperature CE was correlated with the prevalence of T2 DM in workers( P < 0. 01) and showed a linear correlation( nonlinearity test,P > 0. 05). CONCLUSION: Occupational high temperature exposure is associated with the occurrence of T2 DM in male steel workers. The male steel workers with high temperature CE show high prevalence of T2 DM risk.