Occupation and 20-year hearing decline: findings from The HUNT Study.

Area of Science:

• Occupational Health
• Audiology
• Epidemiology

Background:

• Occupational noise exposure is a known risk factor for hearing loss.
• Previous research often used cross-sectional designs or small sample sizes.
• Longitudinal data on occupation-specific hearing decline is limited.

Purpose of the Study:

• To quantify 20-year hearing decline in different occupations.
• To compare hearing changes across various occupational groups.
• To identify occupations with significantly higher rates of hearing loss.

Main Methods:

• Utilized data from 4525 adults in two Norwegian health studies (HUNT2 and HUNT4).
• Employed linear regression models to assess 20-year hearing decline (3-6 kHz thresholds).
• Adjusted for age, sex, ear infections, smoking, and ear pathology, with clerks as the reference group.

Main Results:

• The average 20-year hearing decline was 11.3 dB.
• Workers in craft and related trades (3.9 dB increase) and building frame trades (3.4 dB increase) showed greater hearing decline.
• Higher noise exposure was reported in occupations with more significant hearing loss.

Conclusions:

• Building frame and craft workers experienced a larger long-term hearing decline.
• Observed differences between occupations were modest, suggesting effective preventive measures in Norway.
• Highlights the importance of continued occupational hearing conservation efforts.