Hostname: page-component-7c8c6479df-r7xzm Total loading time: 0 Render date: 2024-03-28T19:12:12.378Z Has data issue: false hasContentIssue false

Genetic and environmental influences on dimensional representations of DSM-IV cluster C personality disorders: a population-based multivariate twin study

Published online by Cambridge University Press:  30 November 2006

TED REICHBORN-KJENNERUD
Affiliation:
Division of Mental Health, Norwegian Institute of Public Health, Oslo, Norway Institute of Psychiatry, University of Oslo, Oslo, Norway
NIKOLAI CZAJKOWSKI
Affiliation:
Division of Mental Health, Norwegian Institute of Public Health, Oslo, Norway
MICHAEL C. NEALE
Affiliation:
The Virginia Institute for Psychiatric and Behavioral Genetics and Departments of Psychiatry and Human Genetics, Medical College of Virginia/Virginia Commonwealth University, Richmond, VA, USA
RAGNHILD E. ØRSTAVIK
Affiliation:
Division of Mental Health, Norwegian Institute of Public Health, Oslo, Norway
SVENN TORGERSEN
Affiliation:
Institute of Psychology, University of Oslo, Oslo, Norway
KRISTIAN TAMBS
Affiliation:
Division of Mental Health, Norwegian Institute of Public Health, Oslo, Norway
ESPEN RØYSAMB
Affiliation:
Division of Mental Health, Norwegian Institute of Public Health, Oslo, Norway Institute of Psychology, University of Oslo, Oslo, Norway
JENNIFER R. HARRIS
Affiliation:
Division of Mental Health, Norwegian Institute of Public Health, Oslo, Norway
KENNETH S. KENDLER
Affiliation:
The Virginia Institute for Psychiatric and Behavioral Genetics and Departments of Psychiatry and Human Genetics, Medical College of Virginia/Virginia Commonwealth University, Richmond, VA, USA

Abstract

Background. The DSM-IV cluster C Axis II disorders include avoidant (AVPD), dependent (DEPD) and obsessive-compulsive (OCPD) personality disorders. We aimed to estimate the genetic and environmental influences on dimensional representations of these disorders and examine the validity of the cluster C construct by determining to what extent common familial factors influence the individual PDs.

Method. PDs were assessed using the Structured Interview for DSM-IV Personality (SIDP-IV) in a sample of 1386 young adult twin pairs from the Norwegian Institute of Public Health Twin Panel (NIPHTP). A single-factor independent pathway multivariate model was applied to the number of endorsed criteria for the three cluster C disorders, using the statistical modeling program Mx.

Results. The best-fitting model included genetic and unique environmental factors only, and equated parameters for males and females. Heritability ranged from 27% to 35%. The proportion of genetic variance explained by a common factor was 83, 48 and 15% respectively for AVPD, DEPD and OCPD. Common genetic and environmental factors accounted for 54% and 64% respectively of the variance in AVPD and DEPD but only 11% of the variance in OCPD.

Conclusion. Cluster C PDs are moderately heritable. No evidence was found for shared environmental or sex effects. Common genetic and individual environmental factors account for a substantial proportion of the variance in AVPD and DEPD. However, OCPD appears to be largely etiologically distinct from the other two PDs. The results do not support the validity of the DSM-IV cluster C construct in its present form.

Type
Original Article
Copyright
2006 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)