title: The associations between unhealthy behaviours, mental stress, and low socio-economic status in an international comparison of representative samples from Thailand and England.
abstract: BACKGROUND
  Socioeconomic status is a recognised determinant of health status, and the association may be mediated by unhealthy behaviours and psychosocial adversities, which, in developed countries, both aggregate in low socioeconomic sectors of the population. We explored the hypothesis that unhealthy behavioural choices and psychological distress do not both aggregate in low socioeconomic status groups in developing countries.
  
  
  METHODS
  Our study is based on a cross-sectional comparison between national population samples of adults in England and Thailand. Psychological distress was assessed using the General Health Questionnaire (GHQ-12) or three anxiety-oriented items from the Kessler scale (K6). Socioeconomic status was assessed on the basis of occupational status. We computed a health-behaviour score using information about smoking, alcohol consumption, fruit and vegetable consumption, and physical activity.
  
  
  RESULTS
  The final sample comprised 40,679 participants. In both countries and in both genders separately, there was a positive association between poor health-behaviour and high psychological distress, and between high psychological distress and low socioeconomic status. In contrast, the association between low socioeconomic status and poor health-behaviour was positive in both English men and women, flat in Thai men, and was negative in Thai women (likelihood ratio test P <0.001).
  
  
  CONCLUSIONS
  The associations between socioeconomic status, behavioural choices, and psychological distress are different at the international level. Psychological distress may be consistently associated with low socioeconomic status, whereas poor health-behaviour is not. Future analyses will test whether psychological distress is a more consistent determinant of socioeconomic differences in health across countries.
authors.affiliation: Department of Epidemiology and Public Health, University College London, 1-19 Torrington Place, London WC1E 6BT, UK. a.lazzarino@ucl.ac.uk.
authors.forename: Antonio Ivan
authors.initials: AI
authors.lastname: Lazzarino
authors.forename: Vasoontara
authors.initials: V
authors.lastname: Yiengprugsawan
authors.forename: Sam-ang
authors.initials: SA
authors.lastname: Seubsman
authors.forename: Andrew
authors.initials: A
authors.lastname: Steptoe
authors.forename: Adrian C
authors.initials: AC
authors.lastname: Sleigh
mesh_terms: D000328:Adult; D000368:Aged; D000428:Alcohol Drinking / Q000523:psychology; D002755:Choice Behavior; D015331:Cohort Studies; D003431:Cross-Cultural Comparison; D003430:Cross-Sectional Studies; D004435:Eating / Q000523:psychology; D004739:England; D005260:Female; D005638:Fruit; D015438:Health Behavior; D054624:Health Status Disparities; D006306:Health Surveys; D006801:Humans; D008297:Male; D008875:Middle Aged; D009043:Motor Activity; D011569:Psychiatric Status Rating Scales; D012307:Risk Factors; D012907:Smoking / Q000523:psychology; D012923:Social Class; D013315:Stress, Psychological / Q000523:psychology*; D013785:Thailand; D014675:Vegetables