Original Article | July 2011
Secondhand Smoke and Sensorineural Hearing Loss in Adolescents FREE
Arch Otolaryngol Head Neck Surg. 2011;137(7):655-662. doi:10.1001/archoto.2011.109.
ABSTRACT
To investigate the hypothesis that second-hand smoke (SHS) exposure is associated with sensorineural hearing loss (SNHL) in adolescents.
A complex, multistage, stratified geographic area design for collecting representative data from the noninstitutionalized US population.
Cross-sectional data from National Health and Nutrition Examination Survey (2005-2006) were available for 1533 participants 12 to19 years of age who underwent audiometric testing, had serum cotinine levels available, and were not actively smoking.
SNHL was defined as an average pure-tone level greater than 15 dB for 0.5, 1, and 2 kHz (low frequency) and 3, 4, 6, and 8 kHz (high frequency).
Secondhand smoke exposure, as assessed by serum cotinine levels, was associated with elevated pure-tone hearing thresholds at 2, 3, and 4 kHz, a higher rate of unilateral low-frequency SNHL (11.8% vs 7.5%;P < .04), and a 1.83-fold increased risk of unilateral low-frequency SNHL in multivariate analyses (95% confidence interval, 1.08-3.41). The prevalence of SNHL was directly related to level of SHS exposure as reflected by serum cotinine levels. In addition, nearly 82% of adolescents with SNHL did not recognize hearing difficulties.
Secondhand smoke is associated with elevated pure-tone thresholds and an increased prevalence of low-frequency SNHL that is directly related to level of exposure, and most affected individuals are unaware of the hearing loss. Thus, adolescents exposed to SHS may need to be closely monitored for early hearing loss with periodic audiologic testing.
Secondhand smoke (SHS) exposure is a profound public health problem, with more than half of children in the United States exposed.1 While exposure rates may vary across regions, by socioeconomic status, race/ethnicity, and sex, its detrimental effects have been demonstrated across all demographic groups.Specifically, prenatal tobacco or childhood SHS exposure has been linked to low birth weight,2 sudden infant death syndrome,3- 5 upper and lower respiratory infections,6- 7 increased asthma severity,6 behavioral problems,8- 9 cognitive problems,10 and otitis media (OM).11 A variety of mechanisms have been proposed to explain the detrimental effects of SHS, including disruption of normal in utero development,12 alterations of the immune system,13 postnatal deterioration of body function, and altered hemodynamics.14
In the auditory system, SHS is a known risk factor for OM.11 Recurrent acute OM is more common in the nearly 60% of children exposed to SHS in the United States.11 While the exact mechanism remains unclear, the increased risk of OM may be through suppression or modulation of the immune system, enhancement of bacterial adherence factors, the consequence of exposure to toxins within SHS, and impairment of the respiratory mucociliary apparatus, leading to Eustachian tube dysfunction.15
Secondhand smoke may also have the potential to have an impact on auditory development, leading to sensorineural hearing loss (SNHL) because of its negative impact on in utero development of the fetus and low birth weight or may lead to decrease in hearing loss due to cochlear, vestibulocochlear nerve VIII damage, or brain damage secondary to childhood and adolescent exposure. To our knowledge, no previous study has examined the possible association between SHS and SNHL among children or adolescents. The present study examines risk factors for SNHL in different age, sex, race/ethnicity, and income or poverty groups among adolescents ages 12 to 19 years and investigates the independent association between SHS and SNHL in this nationally representative sample.
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