Alcohol, tobacco and caffeine use: spouse similarity processes

Behav Genet. 2006 Mar;36(2):201-15. doi: 10.1007/s10519-005-9026-7. Epub 2006 Jan 26.


Spouse similarity research has been largely descriptive yet is of theoretical and empirical importance to understanding individual differences in substance use. The present study considers phenotypic assortment versus social homogamy processes for alcohol, tobacco, and caffeine consumption traits using an extended twin-spouse design. Whereas both assortment processes were supported for quantity of alcohol consumed, phenotypic assortment was supported for quantity of tobacco and caffeine consumed, and social homogamy for tobacco use status. Moderate heritable influences were found for all traits though no shared environmental influences were found beyond those due to social background influences, i.e. those pertaining to social homogamy. Swedish government policies in effect at the time of marriage selection may explain the presence of social homogamy for quantity of alcohol versus quantity of tobacco and caffeine consumed. Social homogamy may be more important for some substance use traits such as alcohol consumption and tobacco use status but not others.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Twin Study

MeSH terms

  • Adult
  • Aged
  • Alcohol Drinking / epidemiology
  • Alcohol Drinking / genetics*
  • Alcohol Drinking / psychology
  • Caffeine*
  • Cross-Sectional Studies
  • Diseases in Twins / epidemiology
  • Diseases in Twins / genetics
  • Diseases in Twins / psychology
  • Female
  • Humans
  • Male
  • Middle Aged
  • Models, Genetic
  • Phenotype
  • Smoking / epidemiology
  • Smoking / genetics*
  • Smoking / psychology
  • Social Environment
  • Spouses / psychology*
  • Spouses / statistics & numerical data
  • Statistics as Topic
  • Substance-Related Disorders / epidemiology
  • Substance-Related Disorders / genetics*
  • Substance-Related Disorders / psychology
  • Sweden


  • Caffeine