Hair Color and Hearing Loss: A Survey in a Group of Military Men

Document Type: Original

Authors

1 Department of otorhinolaryngology, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

2 Ear, Nose, Throat, Head and Neck surgery Research Center, Mashhad University of Medical Sciences, Mashhad, Iran

3 Audiologist, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

4 Department of otorhinolaryngology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran

Abstract

Introduction:
It has been shown that low levels of pigmentation increase susceptibility to noise-induced hearing loss in humans. For this reason, white populations develop more pronounced noise- induced hearing loss in comparison to black populations. Similarly, blue-eyed individuals exhibit greater temporary threshold shift than brown-eyed subjects; still, no strong correlation has been verified between the lightness of hair color and susceptibility to noise-induced hearing loss. This study was performed with the purpose of investigating a possible association between hair color and the degree of hearing loss due to firing noise. Study Design: Prospective observational study. Setting: A tertiary referral center with an accredited otorhinolaryngology-head & neck surgery department.
 
Materials and Methods:
A total of 57 military recruits were divided into two groups; light-colored (blond and light brown) and dark-colored hair (dark brown and black). The two groups were matched based on history of firing noise exposure (number of rounds; type of weapon) and the level of hearing loss at 2, 3, 4, 6 and 8 kHz sound frequencies was compared between them.
 
Results:
The results showed that the mean level of hearing loss of light-colored hair individuals
(20.5±17dB) was significantly greater than that of dark-haired subjects (13.5±11dB),
(P=0.023).
 
Conclusion:
The results indicate that hair color (blond versus black) can be used as an index for predicting susceptibility to noise-induced hearing loss in military environments. Therefore, based on the individual's hair color, upgraded hearing conservation programs are highly recommended.

Keywords