Secondhand smoke and sensorineural hearing loss in adolescents.

OBJECTIVE To investigate the hypothesis that second-hand smoke (SHS) exposure is associated with sensorineural hearing loss (SNHL) in adolescents. DESIGN A complex, multistage, stratified geographic area design for collecting representative data from the noninstitutionalized US population. PARTICIPANTS Cross-sectional data from National Health and Nutrition Examination Survey (2005-2006) were available for 1533 participants 12 to 19 years of age who underwent audiometric testing, had serum cotinine levels available, and were not actively smoking. MAIN OUTCOME MEASURES 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). RESULTS 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. CONCLUSIONS 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.