title: Otoacoustic Emissions in Smoking and Nonsmoking Young Adults.
abstract: OBJECTIVE
  The present study investigates the usefulness of transiently evoked otoacoustic emissions (TEOAEs) and distortion product OAEs (DPOAEs) in detecting small changes in the hearing of young smoking adults.
  
  
  METHODS
  Otoacoustic emissions were acquired from the ears of 48 young adults (age, 20 to 27 years). The dataset was divided into two groups, smoking (24 persons/48 ears) and nonsmoking (24 persons/48 ears). The level of smoking was relatively small in comparison to previous studies, an average of 3.8 years and 8.7 cigarettes per day. In each ear three OAE measurements were made: TEOAEs, DPOAEs, and spontaneous OAEs (SOAEs). Pure tone audiometry and tympanometry were also conducted. Audiometric thresholds did not differ significantly between the datasets. Half-octave-band values of OAE signal to noise ratios and response levels were used to assess statistical differences.
  
  
  RESULTS
  Averaged data initially revealed that differences between the two study groups occurred only for TEOAEs at 1 kHz. However when the datasets were divided into ears with and without SOAEs more differences became apparent, both for TEOAEs and DPOAEs. In ears that exhibited SOAEs, both smokers and nonsmokers, there were no statistically significant differences between evoked OAEs; however in all ears without SOAEs, evoked OAEs were higher in the ears of nonsmokers, by as much as 5 dB. These differences were most prominent in the 1-2 kHz range.
  
  
  CONCLUSIONS
  A general decrease in OAE levels was found in the group of smokers. However, in ears which exhibited SOAEs, there was no difference between the evoked OAEs of smokers and nonsmokers. We conclude that smoking had not yet measurably affected the ears of those with acute hearing (i.e., those who exhibit SOAEs). However, in ears without SOAEs, smokers exhibited smaller evoked OAE amplitudes than nonsmokers, even though their audiometric thresholds were within the norm.
authors.affiliation: Institute of Physiology and Pathology of Hearing, Warsaw, Poland. ; World Hearing Center, Kajetany, Poland.
authors.forename: W Wiktor
authors.initials: WW
authors.lastname: Jedrzejczak
authors.affiliation: Institute of Physiology and Pathology of Hearing, Warsaw, Poland. ; World Hearing Center, Kajetany, Poland. ; Institute of Sensory Organs, Kajetany, Poland.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Koziel
authors.affiliation: Institute of Physiology and Pathology of Hearing, Warsaw, Poland. ; World Hearing Center, Kajetany, Poland.
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Kochanek
authors.affiliation: Institute of Physiology and Pathology of Hearing, Warsaw, Poland. ; World Hearing Center, Kajetany, Poland.
authors.forename: Henryk
authors.initials: H
authors.lastname: Skarzynski
keywords: Audiometry, Pure Tone; Cochlea; Hearing; Otoacoustic Emissions, Spontaneous; Smoking