The more the worse: the grade of noise-induced hearing loss associates with the severity of tinnitus.

Tinnitus disturbs lives and negatively affects the quality of life of about 2% of the adult world population. Research has shown that the main cause of tinnitus is hearing loss. To analyze a possible association of the degree of hearing loss with the severity of tinnitus, we have performed a retrospective study using admission data on 531 patients suffering from chronic tinnitus. We have found that 83% of our tinnitus patients had a high frequency hearing loss corresponding to a noise-induced hearing loss (NIHL). There was a significant correlation between the mean hearing loss and the tinnitus loudness (p < 0.0001). Interestingly, patients suffering from decompensated chronic tinnitus had a greater degree of hearing loss than the patients with compensated form of tinnitus. In addition, we demonstrate that the degree of hearing loss positively correlates with the two subscales ("intrusiveness" and "auditory perceptional difficulties") of the Tinnitus Questionnaire. Our retrospective study provides indirect evidence supporting the hypothesis that the degree of noise-induced hearing loss influences the severity of tinnitus.