Does tinnitus, hearing asymmetry, or hearing loss predispose to occupational injury risk?

Abstract

Objective: To determine the relative contributions of tinnitus, asymmetrical hearing loss, low frequency hearing loss (pure tone average of 0.5, 1, 2, 3 kHz; PTA.₅₁₂₃), or high frequency hearing loss (pure tone average of 4, 6 kHz; PTA₄₆), to acute injury risk among a cohort of production and maintenance workers at six aluminum manufacturing plants, adjusting for ambient noise exposure and other recognized predictors of injury risk. Design: Retrospective analysis. Study sample: The study considered 9920 workers employed during 2003 to 2008. The cohort consisted of 8818 workers (89%) whose complete records were available. Results: Adjusting for noise exposure and other recognized injury predictors, a 25% increased acute injury risk was observed among workers with a history of tinnitus in conjunction with high-frequency hearing loss (PTA₄₆). Low frequency hearing loss may be associated with minor, yet less serious, injury risk. We did not find evidence that asymmetry contributes to injury risk. Conclusion: These results provide evidence that tinnitus, combined with high-frequency hearing loss, may pose an important safety threat to workers, especially those who work in high-noise exposed environments. These at risk workers may require careful examination of their communication and hearing protection needs.

Key Words::

• Tinnitus
• hearing asymmetry
• hearing loss
• workplace health and safety

Acknowledgements

This research was funded by grants from the National Institute on Aging (Disease, Disability and Death in an Aging Workforce, NIH/NIA, 1 R01 AG026291-06), National Institute for Occupational Safety and Health, (Assessing hearing conservation effectiveness, 1 R01 OH010132-01), and a contract with Alcoa Inc.

Note

Data sharing

As an alternative to providing a de-identified data set to the public domain, we allow access for the purpose of re-analyses or appropriate “follow-on” analyses by any qualified investigator willing to sign a contractual covenant with the host institution, limiting use of data to a specific agreed upon purpose and observing the same restrictions as are limited in our contract with Alcoa, such as 60-day manuscript review for compliance purposes.

Declaration of interest: Cantley, Galusha, Tessier-Sherman, Slade, and Cullen receive a portion of their compensation at Yale and Stanford through a long-standing contractual agreement with Alcoa Inc. Dixon-Ernst was employed by Alcoa Inc. during the time this work was conducted.