[Effect of noise on blood pressure in workers of a Venezuelan oil company].

Occupational noise has been related to cardiovascular events, although epidemiologically, there is not a clear explanation. To determine the development of arterial hypertension in workers exposed to a noise level higher than 85 dB (A) and to relate it with the working place, labor antiquity and the use of auditive protection, a case-control study was done in a Venezuelan oil company. Fifty working men, that fulfilled the inclusion and exclusion criteria, were included in each group. The information was obtained from the occupational clinical history, based on international guidelines, to evaluate the parameters of the study, The intensity of environmental noise was obtained according to recommended Venezuelan "Norma COVENIN 1565-95". The mean age of cases and controls were 39 +/- 0.06 and 44 +/- 0.44 years old respectively; the labor seniority was similar in both groups; 22 an 48% of cases and controls respectively had a family history of arterial hypertension (p<0.05), without a high significant prevalence in both groups. In both groups we observed overweight. In 92% of cases and 80% of controls there were normal levels of glucose (p<0.01); 68 and 84% of cases and controls, respectively, presented alterations of the lipid levels (p<0.05). The measurements of environmental noise registered levels that exceeded 85 dB (A), being the mean 87.78 +/- 1.10 dB (A); 94% of the cases used hearing protective equipment and 60% of them presented arterial hypertension and 80% of those that did not used it, showed arterial hypertension. There was not a significant relationship among the auditive loss induced by occupational noise, its intensity and labor seniority with the prevalence of arterial hypertension. We cannot conclude that occupational noise is a decisive factor in the development of arterial hypertension in noise exposed workers.