title: Psychosocial functioning and intelligence both partly explain socioeconomic inequalities in premature death. A population-based male cohort study.
abstract: OBJECTIVE
  The possible contributions of psychosocial functioning and intelligence differences to socioeconomic status (SES)-related inequalities in premature death were investigated. None of the previous studies focusing on inequalities in mortality has included measures of both psychosocial functioning and intelligence.
  
  
  METHODS
  The study was based on a cohort of 49 321 men born 1949-1951 from the general community in Sweden. Data on psychosocial functioning and intelligence from military conscription at ∼18 years of age were linked with register data on education, occupational class, and income at 35-39 years of age. Psychosocial functioning was rated by psychologists as a summary measure of differences in level of activity, power of initiative, independence, and emotional stability. Intelligence was measured through a multidimensional test. Causes of death between 40 and 57 years of age were followed in registers.
  
  
  RESULTS
  The estimated inequalities in all-cause mortality by education and occupational class were attenuated with 32% (95% confidence interval: 20-45%) and 41% (29-52%) after adjustments for individual psychological differences; both psychosocial functioning and intelligence contributed to account for the inequalities. The inequalities in cardiovascular and injury mortality were attenuated by as much as 51% (24-76%) and 52% (35-68%) after the same adjustments, and the inequalities in alcohol-related mortality were attenuated by up to 33% (8-59%). Less of the inequalities were accounted for when those were measured by level of income, with which intelligence had a weaker correlation. The small SES-related inequalities in cancer mortality were not attenuated by adjustment for intelligence.
  
  
  CONCLUSIONS
  Differences in psychosocial functioning and intelligence might both contribute to the explanation of observed SES-related inequalities in premature death, but the magnitude of their contributions likely varies with measure of socioeconomic status and cause of death. Both psychosocial functioning and intelligence should be considered in future studies.
authors.affiliation: Department of Public Health Sciences, Karolinska Institutet, Stockholm, Sweden ; Division of Psychology, Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Daniel
authors.initials: D
authors.lastname: Falkstedt
authors.affiliation: Division of Psychology, Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Kimmo
authors.initials: K
authors.lastname: Sorjonen
authors.affiliation: Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden ; Centre for Social Research on Alcohol and Drugs, Stockholm University, Stockholm, Sweden.
authors.forename: Tomas
authors.initials: T
authors.lastname: Hemmingsson
authors.affiliation: Centre for Cognitive Ageing and Cognitive Epidemiology, Department of Psychology, The University of Edinburgh, Edinburgh, United Kingdom.
authors.forename: Ian J
authors.initials: IJ
authors.lastname: Deary
authors.affiliation: Division of Psychology, Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Bo
authors.initials: B
authors.lastname: Melin
mesh_terms: D000328:Adult; D002423:Cause of Death; D015331:Cohort Studies; D054624:Health Status Disparities; D006801:Humans; D007182:Income; D007360:Intelligence; D008297:Male; D008875:Middle Aged; D061213:Mortality, Premature / Q000639:trends*; D011593:Psychology, Social; D012307:Risk Factors; D012959:Socioeconomic Factors; D013548:Sweden