Introduction: Hearing loss is a major source of morbidity
in the Western world. Precipitating factors are numerous,
however noise exposure is the main cause of hearing
loss among young adults. According to the WHO, roughly
5.3% of the world’s population suffers from hearing loss,
and 50% (1.1 billion) of young adults (age 12-35), are at
risk of hearing loss due to noise exposure during leisure
activities. In recent years, there has been an increase in
the use of personal music players.
Objective: To examine if there has been an increase in
hearing thresholds in recent years.
Methods: A retrospective, cross-sectional study included
500 Navy recruits, ages 17-20, who underwent an
audiometry examination from 1985-1995 (n=124), 2000-
2005 (n=126) and 2010-2015 (n=250). We analyzed the
audiometric examination and socio-demographic data
collected by analyzing personal questionnaires. For each
period, we calculated the hearing threshold mean, the
prevalence of hearing loss by the threshold mean value,
according to NITS (Noise Induced Threshold Shift) criteria
for the worst ear. Hearing loss was categorized for right
and left ears, for low frequencies (0.5, 1, 2 kHz) and high
frequencies (3, 4, 6, 8 kHz) and the hearing loss values
were defined as a value of 15 dB and above. A socioeconomic
index was drawn from the Central Bureau of
Statistics and adapted by locality of residence.
Results: We found an increase in hearing threshold in
the second period (2000-2005). The differences between
periods and frequencies were significance (p<0.001). The
prevalence of NITS was 5.4% for all periods. In the second
period (2000-2005) the prevalence was twice as high as
the first period (1985-1995), though with no statistical
significance. The prevalence of increased hearing loss
(≥15dB) for high frequencies was 16.3% in the left ear
and 11.5% for low frequencies in the right ear, both in the
second period (2000-2005). The overall risk for hearing
loss was in the low frequency range (0.5, 1, 2 kHz), in the
left ear, in comparison between the second period (2000-
2005) and the first period (1985-1995). In addition, the
prevalence of worse ear for low frequency (0.5, 1, 2 kHz)
was 9% and for high frequency (3, 4, 6, 8 kHz) was 15.9%,
both of which were measured in the second period (2000-
2005), but this was not statistically significance. The sociodemographic
data showed that high socio-economic
status correlated to a higher risk for hearing loss.
Conclusions: We demonstrated that hearing loss began
earlier than 2007 (before the introduction of the iPhone)
in contradiction with our hypothesis that smartphones
had a negative impact on hearing. The increase in hearing
thresholds is continuous and may indicate a trend of
hearing loss beginning in young age. We believe that in
order to prevent hearing loss, there must be an increase
in education, awareness and prevention. Further research
is necessary to determine the precise origins and what
preventative measures might be effective.
Presenter:
Soly Elmakias-Sarusi
[email protected]