The Relationship Between Tinnitus Annoyance and Work-Related Noise Exposure History in Older Adults With Sensorineural Hearing Loss.

Background: Exposure to noise at work is one of the major risk factors contributing to the onset of tinnitus. Rates of tinnitus has been shown to range from 35 to 77% among adults with noise-induced hearing loss. Not all who suffers from tinnitus are significantly bothered by it, but for those who experience a severe degree of tinnitus it can lead to depression, anxiety, and poorer quality of life. However, no single cure exists for the condition, and evidence is still lacking on the causes of the onset of tinnitus. Knowledge of factors associated with tinnitus annoyance are important for prevention and rehabilitation in audiological clinics. Thus, the aim of the current study was to investigate if tinnitus is more prevalent among older adults with a noise exposure history and whether older adults with previous work-related noise exposure suffer from a more severe tinnitus than those without an occupational noise exposure history.
Methods: The study was designed as a prospective observational cohort study and included 1176 older adults (≥ 60 years) with bilateral sensorineural hearing loss referred for hearing aid rehabilitation. A non-standardized health-related questionnaire that contained questions on demographic details a long with questions on previous occupational noise exposure to estimate their life-time noise exposure were distributed. A noise emission index was used to calculate their total equivalent noise exposure levels. The tinnitus handicap inventory (THI) questionnaire was used to assess tinnitus annoyance and sent to those answering yes to having experienced a ringing in their ears. All patients underwent a standard pure-tone and speech audiometry (n=1171 complete audiograms).
Results: Out of the 1176 included adults (mean age ± SD: 71.6 ± 6.8 years) 43% answered yes to suffer from tinnitus. Tinnitus was significantly more prevalent among occupationally noise-exposed older adults (X2(2, N=1175) = 43.7, p less than 0.001) with 54% of the noise-exposed reporting tinnitus compared to 35% in the non-exposed group. Regression analysis revealed that the reported THI score was not statistically significant higher among noise-exposed adults com-pared to the non-exposed adults with tinnitus when adjusting for age, sex, better-ear hearing thresholds and hearing aid experience (ꞵ: 3.1 [95%CI: -0.5; 6.7], p=0.09).
Conclusions: An occupational noise exposure history was associated with a higher prevalence of tinnitus in older adults with sensorineural hearing loss. However, the severity of tinnitus assessed with the THI questionnaire was not significantly related to noise exposure status. Other tinnitus questionnaires might be more sensitive to measure differences in tinnitus annoyance. More clinical attention should be given to older adults with a noise exposure history in hearing rehabilitation.