In our daily life, we are exposed to a variety of sounds from conversations in the workplace, to music on the radio, or the hum of traffic during our commute. Typically, these sounds are at a safe level for our hearing health. However, repeated exposure to loud noises from heavy machinery or using headphones at a high volume can lead to noise-induced hearing loss.

The Centers for Disease Control estimates that 40 million Americans between the ages of 20 - 69 suffer from noise induced hearing loss. Men are 2 to 5 times more likely to experience hearing loss than women, but this may be a direct result of gender differences in occupational noise exposure, where men are more likely to work in noisy environments like the military, industry, farming, or aviation [1-3]. This does not exclude the possibility that sex could also impact noise-induced hearing loss on a biological level.

A recent study published in the journal Noise & Health found that a sex bias exists in basic and preclinical research which examines noise-induced hearing loss. The authors reviewed 210 studies on noise-induced hearing loss and found that of the 154 studies (73%) which reported the sex of the animal, the majority (61%) used only male animals. Looking across the 5-year study period, sex bias worsened over time with male-only studies increasing from 37% in 2011 to 56% in 2015.

The authors suggest that sex inclusion in noise-induced hearing loss research is essential to improving hearing health and highlight opportunities where sex as a biological variable can be considered.

To learn more about sex inclusion in biomedical research visit sexinclusion.northwestern.edu.

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References:
1. Lin et al., J Gerontol A Biol Sci Med Sci. 2011 May; 66A(5): 582–590.
2. Lie et al., Int Arch Occup Environ Health. 2016; 89: 351–372.
3. West et al.,  Ear Hear. 2016;37(2):194-205.
4. Lauer and Schrode. Noise Health. 2017;19(90):207-212.