[Study on hearing impairment at high frequency among the flight cadets].

OBJECTIVE

To study the incidence of hearing loss at high frequency and the related influence factors among the flight cadets.

METHOD: Using multi-stage sampling method, 312 flight cadets were randomly selected from grade 2011,2012,2013. The level of binaural hearing threshold at 4 kHz, 6 kHz, 8 kHz were measured by hearing-assistant evaluative apparatus. Whether or not have hearing loss was chosen as dependent variable. Territory, smoking, dietary habit, previous history of tinnitus, the noise exposure time, the vestibular function and the psychological quality were chosen as independent vailables. T test, ANOVA and accumulative logistic regression were performed to analyze the factors influence on hearing impairment by software SPSS 18.0.

RESULT: The morbidity of hearing impairment among flight cadets was 18.9%. Results from single factor analysis showed that the levels of hearing thresholds at 4 kHz, 6 kHz frequency had statistically significant differences between smoking group and non-smoking group (P < 0.05). The levels of hearing thresholds at 4 kHz frequency had statistically significant differences between spicy diet group and not spicy diet group (P < 0.05). The levels of hearing thresholds at 4 kHz, 6 kHz, 8 kHz frequency had statistically significant differences among different strong noise exposure groups (P < 0.05), and that at a same frequency hearing loss increased when noise exposing increased. The levels of hearing thresholds at 4 kHz, 6 kHz frequency had statistically significant difference among different vestibular function groups (P < 0.05). Results of accumulative logistics regression showed that smoking and strong noise exposure were risk factors causing hearing impairment at 4 kHz frequency, and excellent vestibular function seemed to be a preventive factor. Smoking and strong noise exposure were also risk factors causing hearing impairment at 6 kHz frequency.

CONCLUSION

Hearing impairment appears higher morbidity among flight cadets, and it has statistical correlation with smoking, strong noise exposure and vestibular function.