The impact of gender and risk factors for hearing impairment on audiogram changes in military cadets during shooting exercises

Vanja Jovanović; Danilo Vojvodić; Dejan Jovanović; Sonja Marjanović

doi:10.2298/VSP250402051J

Vanja Jovanović Military Medical Academy, *Institute of Occupational Health, Belgrade, Serbia; †University of Defence, Faculty of Medicine of the Military Medical Academy, Belgrade, Serbia
Danilo Vojvodić Military Medical Academy, ‡Institute for Medical Research, Belgrade, Serbia; †University of Defence, Faculty of Medicine of the Military Medical Academy, Belgrade, Serbia
Dejan Jovanović Military Medical Academy, Institute of Radiology, Belgrade, Serbia
Sonja Marjanović University of Defence, Faculty of Medicine of the Military Medical Academy, Belgrade, Serbia

DOI: https://doi.org/10.2298/VSP250402051J

Keywords: audiometry;, hearing loss;, hearing loss, noise-induced;, military medicine;, risk factors;, sex factors.

Abstract

Background/Aim. Military personnel are frequently exposed to high levels of noise, where hearing loss can affect their combat performance. The aim of this study was to assess the impact of impulse noise produced by firearms during shooting exercises, analyze the effect of noise through pure-tone audiometry, and correlate it with sex differences and risk factors for hearing impairment. Methods. The study included 105 cadets, 75 men and 30 women, aged 19 to 25 years, who underwent regular firearm shooting as part of their military training. We observed the results of audiometric examinations conducted at three time points: 24 hrs before noise exposure, immediately after the noise exposure [shooting with a “Crvena Zastava” 99 pistol, i.e., CZ99], and 24 hrs after the shooting. Data on risk factors were obtained from a questionnaire with anamnestic data of the cadets. Results. Immediately after noise exposure, there was significant sensorineural hearing impairment at 2,000 Hz and 4,000 Hz, with complete recovery after 24 hrs. Our study revealed that male participants are more susceptible to this type of noise exposure compared to female participants. Additionally, we found that 22.9% of the respondents had risk factors for post-shooting hearing impairment, which included smoking, noise exposure within the last 7 days, field work within the past 72 hrs, and hereditary hearing loss in the family. Conclusion. Despite the regular use of hearing protection, hearing impairment after acute acoustic trauma caused by shooting in military personnel remains inevitable and is more pronounced in men than in women. Our results suggest that the presence of risk factors for hearing impairment contributes to an increase in the temporary threshold shift, i.e., a decrease in hearing.

References

Yong JS, Wang DY. Impact of noise on hearing in the military. Mil Med Res 2015; 2: 6.

Vidaković А. Occupational medicine, Part 2. Belgrade: Clinical Centre of Serbia, Institute of Occupational Health and Radio-logical Safety “Dr Dragomir Karajović”; 1997. pp 593. (Serbi-an)

Chen KH, Su SB, Chen KT. An overview of occupational noise-induced hearing loss among workers: epidemiology, pathogen-esis, and preventive measures. Environ Health Prev Med 2020; 2(1)5: 65.

Masterson EA, Bushnell PT, Themann CL, Morata TC. Hearing Impairment Among Noise-Exposed Workers - United States, 2003-2012. MMWR Morb Mortal Wkly Rep 2016; 65: 389–94.

Mrena R, Savolainen S, Pirvola U, Ylikoski J. Characteristics of acute acoustical trauma in the Finnish Defence Forces. Int J Audiol 2004; 43(3): 177–81.

Natarajan N, Batts S, Stankovic KM. Noise-induced hearing loss. J Clin Med 2023; 12(6): 2347. Erratum in: J Clin Med 2024; 13(4): 944.

Themann CL, Masterson EA. Occupational noise exposure: A review of its effects, epidemiology, and impact with recom-mendations for reducing its burden. J Acoust Soc Am 2019; 146(5): 3879.

Vidaković А. Occupational medicine, Part 1. Belgrade: Clinical Centre of Serbia, Institute of Occupational Health and Radio-logical Safety “Dr. Dragomir Karajović”; 1996; p. 242. (Serbi-an)

Guida HL, Diniz TH, Kinoshita SK. Acoustic and psychoacous-tic analysis of the noise produced by the police force firearms. Braz J Otorhinolaryngol 2011; 77(2): 163–70.

Oishi N, Schacht J. Emerging treatments for noise-induced hearing loss. Expert Opinion Emerg Drugs 2011; 16(2): 235–45.

Gerhardt KJ, Rodriguez GP, Hepler EL, Moul ML. Ear canal volume and variability in the patterns of temporary threshold shifts. Ear Hear 1987; 8(6): 316–21.

Humes LE, Joellenbeck LM, Durch J. Noise and military service implications for hearing loss and tinnitus. Washington, DC: National Academies Press; 2005. p. 320.

Hertzano R, Lipford EL, Depireux D. Noise: acoustic trauma to the inner ear. Otolaryngol Clin North Am 2020; 53(4): 531–42.

Ryan AF, Kujawa SG, Hammill T, Le Prell C, Kil J. Temporary and Permanent Noise-induced Threshold Shifts: A Review of Basic and Clinical Observations. Otol Neurotol 2016; 37(8): e271–5.

Slepecky N. Overview of mechanical damage to the inner ear: noise as a tool to probe cochlear function. Hear Res 1986; 22: 307–21.

Clark WW, Bohne BA. Effects of noise on hearing. JAMA 1999; 281(17): 1658–9.

OSHA. Occupational Safety and Health Administration 1910.95. - Occupational noise exposure [Internet]. Washing-ton, DC: OSHA; 2025 [accessed 2025 May 28]. Available from: https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.95

Morita S, Nakamary Y, Nakazawa D, Suzuki M, Hoshino K, Fu-kuda A, et al. The Diagnostic and Clinical Utility of Myelop-eroxidase-DNA Complex as a Biomarker in Otitis Media With Antineutrophil Cytoplasmic Antibody-associated Vasculitis. Otol Neurotol 2019; 40(2): e99–106.

Jovanović V, Marjanović S, Perić A, Jovanović D, Radojičić Z, Djukić M, et al. Cytokine changes in nasal secretions after acute acoustic trauma. J Med Biochem 2025; 44(3): 576–86.

Ylikoski ME, Ylikoski JS. Hearing loss and handicap of profes-sional soldiers exposed to gunfire. Scand J Work Environ Health 1994; 20(2): 93–100.

Sommerfeldt JM, Jermihov AP, Erbele ID, Chen BS. Sudden Hearing Loss in the Active Duty Population: An Epidemio-logical Study. Mil Med 2024; 189(Suppl 3): 76–82.

Cruickshanks KJ, Wiley TL, Tweed TS, Klein BE, Klein R, Mares-Perlman JA, et al. Prevalence of hearing loss in older adults in Beaver Dam, Wisconsin. Am J Epidemiol 1988; 148(9): 879–86.

Cheslock M, De Jesus O. Presbycusis [updated 2023 Aug 23; cited 2025 May 28]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025. Available from: https://www.ncbi.nlm.nih.gov/books/NBK559220/

Harris KC, Ahlstrom JB, Dias JW, Kerouac LB, McClaskey CM, Judy R, et al. Neural Presbyacusis in Humans Inferred from Age-Related Differences in Auditory Nerve Function and Structure. J Neurosci 2021; 41(50): 10293–304.

Villavisanis DF, Berson ER, Lauer AM, Cosetti MK, Schrode KM. Sex-based Differences in Hearing Loss: Perspectives From Non-clinical Research to Clinical Outcomess. Otol Neurotol 2020; 41(3): 290–8.

Etchell A, Adhikari A, Weinberg LS, Choo AL, Garnett EO, Chow HM, et al. A systematic literature review of sex differ-ences in childhood language and brain development. Neuro-psychologia 2018; 114: 19–31.

Gur C, Gur RE. Complementarity of sex differences in brain and behavior: from laterality to multimodal neuroimaging. J Neurosci Res 2017; 95(1–2): 189–99.

Solianik R, Brazaitis M, Skurvydas A. Sex-related differences in attention and memory. Medicina (Kaunas) 2016; 52(6): 372–7.

Gogokhia N, Japaridze N, Tizabi Y, Pataraya L, Zhvania MG. Gender differences in anxiety response to high-intensity white noise in rats. Neurosci Lett 2021; 742: 135543.

Lauer AM, Schrode KM. Sex bias in basic and preclinical noise-induced hearing loss research. Noise Health 2017; 19(90): 207–12.

Villavisanis DF, Schrode KM, Lauer AM. Sex bias in basic and preclinical age-related hearing loss research. Biol Sex Differ 2018; 9(1): 23.

Gruber CJ, Tschugguel W, Schneeberger C, Huber JC. Production and actions of estrogens. N Engl J Med 2002; 346(5): 340–52.

Delhez A, Lefebvre P, Péqueux C, Malgrange B, Delacroix L. Au-ditory function and dysfunction: estrogen makes a difference. Cell Mol Life Sci 2020; 77(4): 619–35.

Barakat R, Oakley O, Kim H, Jin J, Ko CJ. Extra-gonadal sites of estrogen biosynthesis and function. BMB Rep 2016; 49(9): 488–96.

Tremere LA, Burrows K, Jeong JK, Pinaud R. Organization of Es-trogen-Associated Circuits in the Mouse Primary Auditory Cortex. J Exp Neurosci 2011; 2011(5): 45–60.

Arnal JF, Lenfant F, Metivier R, Flouriot G, Henrion D, Adlanmerini M, et al. Membrane and nuclear estrogen receptor alpha actions: from tissue specifcity to medical implications. Physiol Rev 2017; 97(3): 1045–87.

Levin ER, Hammes SR. Nuclear receptors outside the nucleus: extranuclear signalling by steroid receptors. Nat Rev Mol Cell Biol 2016; 17(12): 783–97.

Stenberg AE, Wang H, Fish J 3rd, Schrott-Fischer A, Sahlin L, Hultcrantz M. Estrogen receptors in the normal adult and de-veloping human inner ear and in Turner's syndrome. Hear Res 2001; 157(1–2): 87–92.

Engdahl B, Tambs K, Borchgrevink HM, Hoffman HJ. Screened and unscreened hearing threshold levels for the adult popula-tion: results from the Nord-Trøndelag Hearing Loss Study. Int J Audiol 2005; 44(4): 213–30.

Liberman MC, Epstein MJ, Cleveland SS, Wang H, Maison SF. Toward a differential diagnosis of hidden hearing loss in hu-mans. PLoS One 2016; 11(9): e0162726.

Chung DY, Mason K, Gannon RP, Willson GN. The ear effect as a function of age and hearing loss. J Acoust Soc Am 1983; 73(4): 1277– 82.

Lin BM, Wang M, Stankovic KM, Eavey R, McKenna MJ, Curhan GC, et al. Cigarette Smoking, Smoking Cessation and Risk of Hearing Loss in Women. Am J Med 2020; 133(10): 1180–6.

Rocha RL, Atherino CC, Frota SM. High-frequency audiometry in normal hearing military firemen exposed to noise. Braz J Otorhinolaryngol 2010; 76(6): 687–94.

Chen XM, Xue XM, Yu N, Guo WW, Yuan SL, Jiang QQ, et al. The Role of Genetic Variants in the Susceptibility of Noise-Induced Hearin