title: High levels of sound pressure: acoustic reflex thresholds and auditory complaints of workers with noise exposure.
abstract: BACKGROUND
  The clinical evaluation of subjects with occupational noise exposure has been difficult due to the discrepancy between auditory complaints and auditory test results. This study aimed to evaluate the contralateral acoustic reflex thresholds of workers exposed to high levels of noise, and to compare these results to the subjects' auditory complaints.
  
  
  METHODS
  This clinical retrospective study evaluated 364 workers between 1998 and 2005; their contralateral acoustic reflexes were compared to auditory complaints, age, and noise exposure time by chi-squared, Fisher's, and Spearman's tests.
  
  
  RESULTS
  The workers' age ranged from 18 to 50 years (mean=39.6), and noise exposure time from one to 38 years (mean=17.3). We found that 15.1% (55) of the workers had bilateral hearing loss, 38.5% (140) had bilateral tinnitus, 52.8% (192) had abnormal sensitivity to loud sounds, and 47.2% (172) had speech recognition impairment. The variables hearing loss, speech recognition impairment, tinnitus, age group, and noise exposure time did not show relationship with acoustic reflex thresholds; however, all complaints demonstrated a statistically significant relationship with Metz recruitment at 3000 and 4000Hz bilaterally.
  
  
  CONCLUSIONS
  There was no significance relationship between auditory complaints and acoustic reflexes.
authors.affiliation: Medical Sciences School, Universidade Estadual de Campinas (UNICAMP), Campinas, SP, Brazil. Electronic address: alexandresmduarte@gmail.com.
authors.forename: Alexandre Scalli Mathias
authors.initials: AS
authors.lastname: Duarte
authors.affiliation: Medical Sciences School, Universidade Estadual de Campinas (UNICAMP), Campinas, SP, Brazil.
authors.forename: Ronny Tah Yen
authors.initials: RT
authors.lastname: Ng
authors.affiliation: Medical Sciences School, Universidade Estadual de Campinas (UNICAMP), Campinas, SP, Brazil.
authors.forename: Guilherme Machado
authors.initials: GM
authors.lastname: de Carvalho
authors.affiliation: Medical Sciences School, Universidade Estadual de Campinas (UNICAMP), Campinas, SP, Brazil.
authors.forename: Alexandre Caixeta
authors.initials: AC
authors.lastname: Guimarães
authors.affiliation: Medical Sciences School, Universidade Estadual de Campinas (UNICAMP), Campinas, SP, Brazil.
authors.forename: Laiza Araujo Mohana
authors.initials: LA
authors.lastname: Pinheiro
authors.affiliation: Medical Sciences School, Universidade Estadual de Campinas (UNICAMP), Campinas, SP, Brazil.
authors.forename: Everardo Andrade da
authors.initials: EA
authors.lastname: Costa
authors.affiliation: Medical Sciences School, Universidade Estadual de Campinas (UNICAMP), Campinas, SP, Brazil.
authors.forename: Reinaldo Jordão
authors.initials: RJ
authors.lastname: Gusmão
mesh_terms: D000328:Adult; D001309:Auditory Threshold / Q000502:physiology*; D005260:Female; D006317:Hearing Loss, Noise-Induced / Q000175:diagnosis* / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009623:Noise, Occupational / Q000009:adverse effects*; D016273:Occupational Exposure / Q000009:adverse effects*; D012022:Reflex, Acoustic / Q000502:physiology*; D012189:Retrospective Studies; D013997:Time Factors; D055815:Young Adult
keywords: Hearing loss, noise-induced; Noise, occupational; Perda auditiva provocada por ruído; Reflex, acoustic; Reflexo acústico; Ruído ocupacional