A German study has shown that the main cause of tinnitus is hearing loss.
To analyse a possible association of the degree of hearing loss with the severity of tinnitus, the researchers performed a retrospective study using admission data on 531 patients, 280 women and 251 men, suffering from chronic tinnitus.
83% of the 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.
The patients suffering from decompensated chronic tinnitus had a greater degree of hearing loss than the patients with compensated form of tinnitus. In addition, the degree of hearing loss positively correlated with the two subscales (â€œintrusivenessâ€ and â€œauditory perceptional difficultiesâ€) of the survey™s tinnitus questionnaire.
A chain reaction
The study provides indirect evidence supporting the hypothesis that the degree of noise-induced hearing loss influences the severity of tinnitus.
According to the researchers, the study demonstrates that the chain of events started by overexposure to noise not only induces the hearing loss but also tinnitus with its co-morbidities, finally resulting in a decreased quality of life. The degree of hearing impairment is reflected by the severity of tinnitus.