title: The impact of the combination of income and education on the incidence of coronary heart disease in the prospective Reasons for Geographic and Racial Differences in Stroke (REGARDS) cohort study.
abstract: BACKGROUND
  We investigated the association between income-education groups and incident coronary heart disease (CHD) in a national prospective cohort study.
  
  
  METHODS
  The REasons for Geographic And Racial Differences in Stroke study recruited 30,239 black and white community-dwelling adults between 2003 and 2007 and collected participant-reported and in-home physiologic variables at baseline, with expert adjudicated CHD endpoints during follow-up. Mutually exclusive income-education groups were: low income (annual household income <$35,000)/low education (< high school), low income/high education, high income/low education, and high income/high education. Cox models estimated hazard ratios (HR) for incident CHD for each exposure group, examining differences by age group.
  
  
  RESULTS
  At baseline, 24,461 participants free of CHD experienced 809 incident CHD events through December 31, 2011 (median follow-up 6.0 years; interquartile range 4.5-7.3 years). Those with low income/low education had the highest incidence of CHD (10.1 [95% CI 8.4-12.1]/1000 person-years). After full adjustment, those with low income/low education had higher risk of incident CHD (HR 1.42 [95% CI: 1.14-1.76]) than those with high income/high education, but findings varied by age. Among those aged <65 years, compared with those reporting high income/high education, risk of incident CHD was significantly higher for those reporting low income/low education and low income/high education (adjusted HR 2.07 [95% CI 1.42-3.01] and 1.69 [95% CI 1.30-2.20], respectively). Those aged ≥ 65 years, risk of incident CHD was similar across income-education groups after full adjustment.
  
  
  CONCLUSIONS
  For younger individuals, low income, regardless of education, was associated with higher risk of CHD, but not observed for ≥ 65 years. Findings suggest that for younger participants, education attainment may not overcome the disadvantage conferred by low income in terms of CHD risk, whereas among those ≥ 65 years, the independent effects of income and education are less pronounced.
authors.affiliation: Department of Human Studies, School of Education, College of Arts and Sciences, University of Alabama at Birmingham, 901 13th Street South, Birmingham, AL, 35294-1250, USA. mwl3099@uab.edu.|Department of Medicine, School of Medicine, University of Alabama at Birmingham, 1720 2nd Ave South, Birmingham, AL, 35294-4410, USA. mwl3099@uab.edu.
authors.forename: Marquita W
authors.initials: MW
authors.lastname: Lewis
authors.affiliation: Department of Medicine, School of Medicine, University of Alabama at Birmingham, 1720 2nd Ave South, Birmingham, AL, 35294-4410, USA. khodneva@uab.edu.
authors.forename: Yulia
authors.initials: Y
authors.lastname: Khodneva
authors.affiliation: Department of Medicine, School of Medicine, University of Alabama at Birmingham, 1720 2nd Ave South, Birmingham, AL, 35294-4410, USA. nredmond@uabmc.edu.
authors.forename: Nicole
authors.initials: N
authors.lastname: Redmond
authors.affiliation: Department of Medicine, School of Medicine, University of Alabama at Birmingham, 1720 2nd Ave South, Birmingham, AL, 35294-4410, USA. rdurant@uabmc.edu.
authors.forename: Raegan W
authors.initials: RW
authors.lastname: Durant
authors.affiliation: Department of Biostatistics, School of Public Health, University of Alabama at Birmingham, 1665 University Boulevard, Birmingham, AL, 35294-0022, USA. sejudd@uab.edu.
authors.forename: Suzanne E
authors.initials: SE
authors.lastname: Judd
authors.affiliation: Department of Human Studies, School of Education, College of Arts and Sciences, University of Alabama at Birmingham, 901 13th Street South, Birmingham, AL, 35294-1250, USA. larrellw@uab.edu.
authors.forename: Larrell L
authors.initials: LL
authors.lastname: Wilkinson
authors.affiliation: Department of Epidemiology, School of Public Health, University of Alabama at Birmingham, 1665 University Boulevard, Birmingham, AL, 35294-0022, USA. vjhoward@uab.edu.
authors.forename: Virginia J
authors.initials: VJ
authors.lastname: Howard
authors.affiliation: Department of Medicine, School of Medicine, University of Alabama at Birmingham, 1720 2nd Ave South, Birmingham, AL, 35294-4410, USA. msafford@uabmc.edu.
authors.forename: Monika M
authors.initials: MM
authors.lastname: Safford
mesh_terms: D017677:Age Distribution; D000368:Aged; D044383:Black People; D003324:Coronary Artery Disease / Q000453:epidemiology* / Q000208:ethnology; D005260:Female; D006801:Humans; D015994:Incidence; D007182:Income; D008297:Male; D008875:Middle Aged; D011203:Poverty; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012306:Risk; D017678:Sex Distribution; D012959:Socioeconomic Factors; D044465:White People