Abstract from the Belgian study:
BACKGROUND: It is not yet clear whether chronic fatigue syndrome (CFS) is associated with elevated levels of personality disorders.
PURPOSE: This study aims to determine the prevalence of DSM-IV axis II personality disorders among patients with CFS.
METHODS: We examined the prevalence of personality disorders in a sample of 92 female CFS patients and in two well-matched control groups, i.e., normal community individuals (N=92) and psychiatric patients (N=92). Participants completed the assessment of DSM-IV personality disorders questionnaire (ADP-IV), which yields a categorical and dimensional evaluation of personality disorder features.
RESULTS: The prevalence of personality disorders in CFS patients (16.3 %) was significantly lower than in psychiatric patients (58.7 %) and was similar to that in the community sample (16.3 %). Similar results were found for dimensional and pseudodimensional scores, except for the Depressive (DE) and Obsessive-Compulsive Personality Disorder (O-C) subscales. Patients with CFS had significantly higher levels of DE features compared to normal controls and similar dimensional scores on the O-C scale compared to psychiatric controls.
CONCLUSIONS: Although the CFS sample was characterized by depressive and obsessive-compulsive personality features, this study provides no evidence for the assumption that these patients generally show a higher prevalence of axis II pathology. Given the conflicting findings in this area, future studies using multiple measures to assess personality disorders in CFS are needed to substantiate these findings.