title: Occupational noise exposure, social class, and risk of ischemic heart disease and all-cause mortality--a 16-year follow-up in the Copenhagen Male Study.
abstract: OBJECTIVE
  Long-term exposure to occupational noise may be associated with an increased risk of ischemic         heart disease (IHD) and all-cause mortality. However, the issue remains unsettled. Only a small number of longitudinal         studies have been carried out, and control for potential confounders including a strong correlate of noise exposure         namely social class may have been insufficient.
  
  
  METHODS
  We carried out a 16-year follow-up of 2998 men aged         53-75 years without overt cardiovascular disease.
  
  
  RESULTS
  Overall, 197 men (6.6%) died due to IHD and 1192         (39.8%) from all-causes. Of the 2998 men, 1008 (33.6%) reported exposure to occupational noise for ≥5 years [mean         25.4, standard deviation (SD) 12.5 years]; among these men, 47.3% reported hearing impairment versus only 24.8% among         unexposed men (63.0%). Referencing unexposed men, the hazard ratio (HR) for IHD mortality was 0.97 [95% confidence         interval (95% CI) 0.71-1.33], and the HR for all-cause mortality was 1.01 (95% CI 0.89-1.15) when adjusting         for potential confounders: age, hearing impairment, blood pressure, diabetes, fasting serum triglycerides and         high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, glucosuria, cancer, body mass index,         alcohol, tobacco, leisure-time physical activity, and social class. Stratified analyses of high and low social classes         confirmed the overall results.
  
  
  CONCLUSIONS
  Cumulative occupational exposure to noise was strongly associated with         hearing impairment, but not with death from either IHD or all-cause mortality in a long-term follow-up adjusting for         established cardiovascular risk factors including low social class.
authors: Copenhagen Male Study, Epidemiologic Research Unit, Copenhagen University Hospital, Bispebjerg, Denmark. PSUA0001@bbh.regionh.dk
authors: Poul
authors: P
authors: Suadicani
authors: Hans Ole
authors: HO
authors: Hein
authors: Finn
authors: F
authors: Gyntelberg
mesh_terms: D000368:Aged; D003718:Denmark / Q000453:epidemiology; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009026:Mortality; D017202:Myocardial Ischemia / Q000453:epidemiology* / Q000209:etiology; D009622:Noise / Q000009:adverse effects*; D016273:Occupational Exposure; D012923:Social Class