Data from the Medical Registry of the Companhia Siderúrgica Nacional de Volta Redonda (Rio de Janeiro, Brazil) drawn from a sample of 426 working nem from nine occupational categories are analysed. The aim of this study was to asses the evolution of BP from admittance to last periodical examination. About 90% of the workers had 20 to 50 years at any of the measures. The mean interval between the measures was 13,5 years for those with at least 5 years in activity. It was not possible to reject homogeneity of means of systolic or diastolic annual increments among occupational groups. In relation to the observed variations, significant systolic increases occurs only in the category of clerks and storekeepers as well as in that of laboratory and quality control workers, with at least 5 years in activity. Regarding diastolic pressure, occupational groups wich undergo significant increases were those of clerks and storekeepers, machinery and specific occupations of production, eletro-mechanics of maintenance, building construction, transportation/communications and non-skilled workers. The shift from a status of normo tension to the one of high BP (systolic 140 or diastolic 90 mmHg) was also analysed. Only non-skilled workers had significant changes in status of systolic. The results for the diastolic matched the ones observed for the increases. It was noticeable the greatest increase of diastolic between the measures among building construction workers. Whereas managers and technical/scientifical personnel showed the smallest BP variations. Environmental factors linked with BP elevation like noise, heat, assembly line and others are present in this steel industry. The data points out a higher risk of PB elevation in particular occupational groups. These findings stress the recommendations of different oproaches by the mecical services in relation to this issue.
