Occupational noise and demographic factors in hearing.
The effects of age, sex, socioeconomic background and noise exposure on hearing were examined in a population sample. Subjects, aged between 17 and 80 years, were selected from the electoral register using a stratified random sampling technique based on age and reported hearing difficulty. Exposure to occupational, social and gunfire noises was estimated retrospectively from a structured interview. Analysis of the audiograms of 2,162 subjects free from any material conductive impairment led to a simple model requiring only first-order factors of age, occupational group (manual or non-manual) and occupational noise exposure, but with parameters different for the two sexes. These models accounted for up to 58% of the variance in hearing threshold level (HTL), depending on frequency. It was not possible to separate out gunfire noise exposure as a factor because of a confounding effect of age. For females there was no significant effect of noise exposure, possibly owing to small numbers of noise-exposed females. The dependence of HTL on age agreed well with published literature, particularly for males. For males, noise exposure was associated with a modest increase in HTL, mainly between 3 and 6 kHz. The model was consistent with reported HTLs for males with equivalent noise exposure.
Lutman
M E
ME
MRC Institute of Hearing Research, Nottingham.
Spencer
H S
HS
D000328:Adult; D000367:Age Factors; D000368:Aged; D001299:Audiometry; D001309:Auditory Threshold / Q000502:physiology; D005260:Female; D006317:Hearing Loss, Noise-Induced / Q000453:epidemiology*; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D009623:Noise, Occupational / Q000009:adverse effects*; D011304:Presbycusis / Q000453:epidemiology; D012494:Sampling Studies; D012737:Sex Factors; D012959:Socioeconomic Factors; D006113:United Kingdom / Q000453:epidemiology