Length of occupational noise exposure and blood pressure.

A cross-sectional study was performed in the Paris area, with a total of 7901 subjects; 432 of them were exposed to occupational noise greater than or equal to 85 dBA. Noise was measured by the worksite physicians, and length of exposure was collected through interview. The subjects exposed to noise were mainly workers, their body mass index was higher and their job characteristics different from the other subjects, assembly line, shift-work and job under time pressure being more frequent. Blood pressure (BP) was higher among the exposed subjects; this was no longer the case after adjustment for age, body mass index and alcohol intake. Taking length of exposure into account, BP and the prevalence of hypertension increased for durations greater than or equal to 25 years. This relationship was still significant after adjustment for age, body mass index and alcohol intake. These results suggest that a long occupational noise exposure is a risk factor for high blood pressure.