Behavior Genetics

, Volume 37, Issue 4, pp 547–558 | Cite as

Twin Pair Resemblance for Psychiatric Hospitalization in the Swedish Twin Registry: A 32-year Follow-up Study of 29,602 Twin Pairs

  • Carol A. Prescott
  • Jonathan W. Kuhn
  • Nancy L. Pedersen
Original Paper



Allgulander et al. (Allgulander C, Nowak J, Rice JP (1991) Acta Psychiatr Scand 83, 12) published twin pair analyses of psychiatric hospitalization for like-sex pairs from the Swedish Twin Registry born 1926–1958. As noted in a subsequent letter (Allgulander C, Nowak J, Rice JP (1992) Acta Psychiatr Scand 86, 421), several features of the original study resulted in under-ascertainment of cases and underestimated heritability, particularly for alcoholism. The present report updates the prior results by using 17 additional years of follow-up, including members of opposite-sex twin pairs, and addressing biases arising from cohort effects and from excluding pairs with unknown zygosity.


Registry records for 29,602 twin pairs born 1926–1958 were matched against national databases of psychiatric and medical hospitalizations from 1972–2000 to obtain ICD diagnostic codes. Zygosity was known for 10,903 opposite-sex pairs and 15,401 like-sex pairs who participated previously in research. Twin-pair resemblance and genetic and environmental variance proportions were estimated for hospitalization for alcoholism, affective disorders, psychosis, and (in females) anxiety disorders.


Hospitalization rates during the ascertainment window were: alcoholism: males = 3.67%, females = 0.94%; affective disorders: males = 1.99%, females = 2.75%; anxiety disorders: males = 0.46%, females = 0.74%; and psychotic disorders: males = 1.70%, females = 1.96%. Twins from like-sex pairs with unknown zygosity had significantly higher prevalences than those with known zygosity. Tetrachoric correlations and heritability estimates were affected by the method used to model unknown zygosity and cohort effects.


Inclusion of additional follow-up information, opposite-sex twin pairs, age-adjustment, and use of current ICD definitions yielded higher heritability estimates for alcoholism, anxiety disorders, and psychosis than previously published for this nationally-representative sample of twins from Sweden. The results show that relatively small selection biases can alter twin study results and underscore the importance of addressing under-ascertainment of cases in genetic research based on volunteers.


Alcoholism Depression Psychosis Anxiety Ascertainment 



The Swedish Twin Registry is supported by grants from the Swedish Scientific Council, the Swedish Ministry of Higher Education, and Astra Zeneca. The authors are grateful to Lisa Halberstadt for helpful comments and J. J. McArdle for statistical advice. Preparation of this manuscript was supported by grants R01-AA-11408 and K01-AA-00236 from the U.S. National Institutes of Health and an Independent Investigator award from the National Alliance for Research on Schizophrenia and Affective Disorders (to CAP). Rebecca Ortiz assisted with manuscript preparation.


  1. Allgulander C, Nowak J, Rice JP (1991) Psychopathology and treatment of 30,334 twins in Sweden: II. Heritability estimates of psychiatric diagnosis and treatment in 12,884 twin pairs. Acta Psychiatr Scand 83:12–15PubMedGoogle Scholar
  2. Allgulander C, Nowak J, Rice JP (1992) Psychopathology and treatment of 30,334 twins in Sweden (Letter). Acta Psychiatr Scand 86:421–422PubMedGoogle Scholar
  3. Bohman M, Sigvardsson S, Cloninger CR (1981) Maternal inheritance of alcohol abuse. Cross-fostering analysis of adopted women. Arch Gen Psychiatry 38:965–969PubMedGoogle Scholar
  4. Cardno AG, Gottesman II (2000) Twin studies of schizophrenia from bow-and-arrow concordances to star wars Mx and functional genomics. Am J Med Genet 97:12–17PubMedCrossRefGoogle Scholar
  5. Cloninger CR, Bohman M, Sigvardsson S (1981) Inheritance of alcohol abuse. Cross-fostering analysis of adopted men. Arch Gen Psychiatry 38:861–868PubMedGoogle Scholar
  6. Eley TC, Collier D, McGuffin P (2002) Anxiety and eating disorders. In: McGuffin P, Owen MJ, Gottesman II (eds) Psychiatric genetics and genomics. Oxford University Press, London, pp 303–340Google Scholar
  7. Falconer DS (1965) The inheritance of liability to certain diseases, estimated from the incidence among relatives. Ann Hum Genet 29:51–76Google Scholar
  8. Foley DL, Neale MC, Kendler KS (1998) Reliability of a lifetime history of major depression: implications for heritability and comorbidity. Psychol Med 28:857–870PubMedCrossRefGoogle Scholar
  9. Heath AC, Nyholt DR, Neuman R, Madden PA, Bucholz KK, Todd RD, Nelson EC, Montgomery GW, Martin NG (2003) Zygosity diagnosis in the absence of genotypic data: an approach using latent class analysis. Twin Res 6:22–26PubMedCrossRefGoogle Scholar
  10. Jones I, Kent L, Craddock N (2002) Genetic of affective disorders. In: McGuffin P, Owen MJ, Gottesman II (eds) Psychiatric genetics and genomics. Oxford University Press, London, pp 211–245Google Scholar
  11. Kaij L (1960) Alcoholism in twins. Almqvist and Wiksell, StockholmGoogle Scholar
  12. Kendler KS, Holm NV (1985) Differential enrollment in twin registries: its effect on prevalence and concordance rates and estimates of genetic parameters. Acta Genetica Medica et Gemellologia 34:125–140Google Scholar
  13. Kendler KS, Pedersen NC, Neale MC, Mathe AA (1995) A pilot Swedish twin study of affective illness including hospital- and population-ascertained subsamples: results of model fitting. Behav Genet 25:217–232PubMedCrossRefGoogle Scholar
  14. Kendler KS, Prescott CA, Neale MC, Pedersen NL (1997) Temperance board registration for alcohol abuse in a national sample of Swedish male twins, born 1902 to 1949. Arch Gen Psychiatry 54:178–184PubMedGoogle Scholar
  15. Kessler RC, McGonagle KA, Zhao S, Nelson CB, Hughes M, Eshleman S, Wittchen H-U, Kendler KS (1994) Lifetime and 12-month prevalence of DSM-III-R psychiatric disorders in the United States: results from the National Comorbidity Survey. Arch Gen Psychiatry 51:8–10PubMedGoogle Scholar
  16. Lichtenstein P, deFaire U, Floderus B, Svartengren M, Svedberg P, Pedersen NL (2002) The Swedish twin registry: a unique resource for clinical, epidemiological and genetic studies. J Intern Med 252:184–205PubMedCrossRefGoogle Scholar
  17. Maes HH, Neale MC, Kendler KS, Hewitt JK, Silberg JL, Foley DL, Meyer JM, Rutter M, Simonoff E, Pickles A, Eaves LJ (1998) Assortative mating for major psychiatric diagnoses in two population-based samples. Psychol Med 28:1389–1401PubMedCrossRefGoogle Scholar
  18. McGuffin P, Katz R, Watkins S, Rutherford J (1996) A hospital based twin register of the heritability of DSM-IV unipolar depression. Arch Gen Psychiatry 53:129–136PubMedGoogle Scholar
  19. Medlund P, Cederlof R, Floderus-Myrhed B, Friberg L, Sorensen SA (1976) A new Swedish twin registry containing environmental and medical base line data from about 14,000 same-sexed pairs born 1926–58. Acta Med Scand Suppl. 600, 1–111Google Scholar
  20. Merikangas KR, Mehta RL, Molnar BE, Walters EE, Swendsen JD, Aguilar-Gaziola S, Bijl R, Borges G, Caraveo-Anduaga JJ, DeWit DJ, Kolody B, Vega WA, Wittchen H-U, Kessler RC (1998) Comorbidity of substance use disorders with mood and anxiety disorders: results of the international consortium in psychiatric epidemiology. Addict Behav 23:893–907PubMedCrossRefGoogle Scholar
  21. Muthen LK, Muthen BO (2003) Mplus user’s guide. Version 3.0. Muthen & Muthen., Los Angeles, CAGoogle Scholar
  22. Neale MC (2003) A finite mixture distribution model for data collected from twins. Twin Res 6:235–239PubMedCrossRefGoogle Scholar
  23. Owen MJ, O’Donovan MC, Gottesman II (2002) Schizophrenia. In: McGuffin P, Owen MJ, Gottesman II (eds) Psychiatric genetics and genomics. Oxford University Press, London, pp 247–266Google Scholar
  24. Pedersen NL, Lichtenstein P, Svedberg P (2002) The Swedish twin registry in the third millenium. Twin Res 5:427–432PubMedCrossRefGoogle Scholar
  25. Prescott CA (2003) Alcoholism and drug addiction. Encyclopedia of the human genome. Nature Publishing Group, London. (
  26. Prescott CA (2004). Using the Mplus computer program to estimate models for continuous and categorical data from twins. Behav Genet 34:7–40CrossRefGoogle Scholar
  27. Prescott CA, Kendler KS (2000) Influence of ascertainment strategy on finding sex differences in genetic influences from twin studies of alcoholism. Neuropsychiatric Genetics 96:754–761PubMedCrossRefGoogle Scholar
  28. Reed T, Page WF, Viken RJ, Christian JC (1996) Genetic predisposition to organ-specific endpoints of alcoholism. Alcohol Clin Exp Res 20:1528–1533PubMedCrossRefGoogle Scholar
  29. Rose RJ, Kaprio J, Williams CJ, Viken R, Obremski K (1990) Social contact and sibling similarity: facts, issues, and red herrings. Behav Genet 20:763–778PubMedCrossRefGoogle Scholar
  30. Soldani F, Sullivan PF, Pedersen NL (2005) Mania in the Swedish twin registry: criterion validity and prevalence. Aust N Z J Psychiatry 39:235–243PubMedCrossRefGoogle Scholar
  31. Sullivan PF, Kendler KS, Neale MC (2003) Schizophrenia as a complex trait: evidence from a meta-analysis of twin studies. Arch Gen Psychiatry 60:1187–1192PubMedCrossRefGoogle Scholar
  32. Sullivan PF, Neale MC, Kendler KS (2000) Genetic epidemiology of major depression: review and meta analysis. Am J Psychiatry 157:1552–1562PubMedCrossRefGoogle Scholar
  33. True WR, Heath AC, Bucholz K, Slutske W, Romels JC, Scherrer JF, Lin N, Eisen SA, Goldberg J, Lyons M, Tsuang MT (1996) Models of treatment seeking for alcoholism: the role of genes and environment. Alcohol Clin Exp Res 20:1577–1581PubMedCrossRefGoogle Scholar
  34. World Health Organization (1960) International classification of diseases––seventh revision. World Health Organization, GenevaGoogle Scholar
  35. World Health Organization (1968) International classification of diseases, eighth revision. World Health Organization, GenevaGoogle Scholar
  36. World Health Organization (1978) International classification of diseases, ninth revision. World Health Organization, GenevaGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2007

Authors and Affiliations

  • Carol A. Prescott
    • 1
  • Jonathan W. Kuhn
    • 2
  • Nancy L. Pedersen
    • 3
  1. 1.Department of PsychologyUniversity of Southern CaliforniaLos AngelesUSA
  2. 2.First Health Services CorpGlen AllenUSA
  3. 3.Department of Medical Epidemiology and BiostatisticsKarolinska InstitutetStockholmSweden

Personalised recommendations