title: Social disparities in heart disease risk and survivor bias among autoworkers: an examination based on survival models and g-estimation.
abstract: OBJECTIVE
  To examine gender and racial disparities in ischaemic heart disease (IHD) mortality related to metalworking fluid exposures and in the healthy worker survivor effect.
  
  
  METHODS
  A cohort of white and black men and women autoworkers in the USA was followed from 1941 to 1995 with quantitative exposure to respirable particulate matter from water-based metalworking fluids. Separate analyses used proportional hazards models and g-estimation.
  
  
  RESULTS
  The HR for IHD among black men was 3.29 (95% CI 1.49 to 7.31) in the highest category of cumulative synthetic fluid exposure. The HR for IHD among white women exposed to soluble fluid reached 2.44 (95% CI 0.96 to 6.22). However, no increased risk was observed among white men until we corrected for the healthy worker survivor effect. Results from g-estimation indicate that if white male cases exposed to soluble or synthetic fluid had been unexposed to that fluid type, then 1.59 and 1.20 years of life would have been saved on average, respectively.
  
  
  CONCLUSIONS
  We leveraged the strengths of two different analytic approaches to examine the IHD risks of metalworking fluids. All workers may have the same aetiological risk; however, black and female workers may experience more IHD from water-based metalworking fluid exposure because of a steeper exposure-response or weaker healthy worker survivor effect.
authors.affiliation: School of Public Health, Environmental Health Sciences, University of California, Berkeley, California, USA.
authors.forename: Sadie
authors.initials: S
authors.lastname: Costello
authors.affiliation: School of Public Health, Environmental Health Sciences, University of California, Berkeley, California, USA.
authors.forename: Sally
authors.initials: S
authors.lastname: Picciotto
authors.affiliation: Division of General Medical Disciplines, Stanford University School of Medicine, Stanford, California, USA.
authors.forename: David H
authors.initials: DH
authors.lastname: Rehkopf
authors.affiliation: School of Public Health, Environmental Health Sciences, University of California, Berkeley, California, USA.
authors.forename: Ellen A
authors.initials: EA
authors.lastname: Eisen
mesh_terms: D001741:Black or African American; D000368:Aged; D000395:Air Pollutants, Occupational / Q000009:adverse effects*; D001336:Automobiles; D015982:Bias; D005260:Female; D054624:Health Status Disparities; D015989:Healthy Worker Effect; D006801:Humans; D008297:Male; D066192:Manufacturing Industry; D008670:Metals; D008875:Middle Aged; D015233:Models, Statistical; D017202:Myocardial Ischemia / Q000401:mortality*; D009784:Occupational Diseases / Q000401:mortality*; D016273:Occupational Exposure / Q000009:adverse effects*; D009790:Occupations; D052638:Particulate Matter / Q000009:adverse effects; D012307:Risk Factors; D012737:Sex Factors; D015996:Survival Rate; D014481:United States / Q000453:epidemiology; D044465:White People
chemical_list: D000395:Air Pollutants, Occupational; D008670:Metals; D052638:Particulate Matter
keywords: G-Estimation; Health Disparities; Healthy Worker Survivor Effect; Heart Disease; Metalworking Fluid