Noisy workplaces linked with heart disease
MedWire News: Chronic exposure to occupational noise is associated with an increased prevalence of coronary heart disease (CHD), with the link being particularly strong in the under-50s, men, and smokers, study findings show.
Previous research into the health impact of occupational noise exposure has been inconsistent and limited by methodological issues. In this study, Wenqi Gan (University of British Columbia, Vancouver, Canada) re-examined the issue using nationally representative, cross-sectional data from the Third US National Health and Examination Survey.
Of 6307 participants, 1236 (21.1%) reported being currently exposed to loud noise at work and having been so for at least 3 months; of these, the accumulated exposure time was classified as "short" in 421 people, "medium" in 399, and "long" in 416.
The remaining 5071 participants said they had never been exposed to loud noise at work.
After adjusting for important variables, those exposed to occupational noise were more likely to have angina pectoris, CHD, and isolated diastolic hypertension than those without such exposure, with adjusted odds ratios of 2.91, 2.04, and 2.23, respectively.
Each of these associations showed a clear dose-response relationship, being strongest in those with long durations of exposure and weakest in those with short exposure.
Finally, subgroup analyses found that the associations between noise exposure and each of the three cardiovascular endpoints were particularly strong in participants aged <50 years, men, and current smokers.
Noise exposure showed no association with circulating levels of lipids or inflammatory markers, however, leaving the mechanism underlying the results unclear.
"This study suggests that excess noise exposure in the workplace is an important occupational health issue and deserves special attention," conclude Gan and co-authors in the journal Occupational and Environmental Medicine.
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By Joanna Lyford