Occupational noise exposure and asymmetric hearing loss: Results from the HUNT population study in Norway

• Published in: American journal of industrial medicine 2020-06, Vol.63 (6), p.535-542
• Main Authors: Aarhus, Lisa, Engdahl, Bo
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Aged; Aged, 80 and over; asymmetric hearing loss; Asymmetry; Audiometry; Audiometry, Pure-Tone - statistics & numerical data; Auditory Threshold; Confidence intervals; Cross-Sectional Studies; Diabetes mellitus; Ear; Ears & hearing; Female; Frequency ranges; Geriatrics; Hearing; Hearing loss; Hearing Loss, Noise-Induced - epidemiology; Hearing Loss, Noise-Induced - etiology; Hearing protection; Humans; Male; Men; Middle Aged; Noise; Noise levels; Noise, Occupational - adverse effects; Noise, Occupational - statistics & numerical data; Norway - epidemiology; Occupational Diseases - epidemiology; Occupational Diseases - etiology; Occupational exposure; Occupational Exposure - adverse effects; Occupational Exposure - statistics & numerical data; occupational medicine; occupational noise exposure; Odds Ratio; Population; Population studies; Population-based studies; population‐based study; Prevalence; Regression Analysis; Regression models; Statistical analysis; Trauma; Young Adult
• ISSN: 0271-3586; 1097-0274
• DOI: 10.1002/ajim.23105

Background A large population study with adequate data on confounders is required to determine whether asymmetric hearing loss (AHL) is associated with occupational noise exposure. Methods We performed a cross‐sectional population study in Norway (the Health Investigation in Nord‐Trøndelag: HUNT) with 24 183 participants, using pure‐tone audiometry and questionnaires. AHL was defined as a difference in hearing threshold between the right and left ears of greater than or equal to 15 dB for the pure‐tone average of 0.5 to 2 or 3 to 6 kHz. Results The mean age of the participants was 53 years (range, 19‐99); 53% were women. The prevalence of AHL in this general Norwegian population was 6% for the 0.5 to 2 kHz range and 15% for 3 to 6 kHz. In unadjusted regression models, subjects reporting prolonged occupational noise exposure to high‐level noise sources (N = 1652) had a higher risk of AHL at 3 to 6 kHz than those reporting no prior exposure (odds ratio [OR], 1.98; 95% confidence interval [CI], 1.75‐2.25). After adjustment for age and sex, OR was 1.08; (95% CI, 0.95‐1.24). After additional adjustment for head trauma, ear infections, blasting or shooting (all associated with AHL), smoking, and diabetes, OR was 1.00 (95% CI, 0.87‐1.16). No association between occupational noise and right‐ear hearing threshold advantage (left‐right ear difference) was observed after adjustment for confounders. Conclusion Our study suggests that AHL is relatively common in the general population, especially at the high‐frequency range in men and elderly subjects. Our study showed no relation between occupational noise exposure and AHL after confounder adjustment.