Chronic fatigue syndrome and DSM-IV personality disorders

Personality is an important factor in the research of the chronic fatigue syndrome (CFS). Although some studies report a high rate of personality disorders--around the 40% level--in samples of patients with CFS, the generalizability of these findings can be questioned. The present study evaluates the prevalence of Diagnostic and Statistical Manual for Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR) personality disorders in a sample of female CFS patients and in two control groups.

The ADP-IV questionnaire (Assessment of DSM Personality Disorders IV) was used to assess the DSM-IV-TR personality disorders at a dimensional and categorical level in a sample of 50 female CFS patients and in two matched control samples of Flemish civilians (n=50) and psychiatric patients (n=50).

The results indicate a striking lack of statistical significant differences between the CFS sample and the Flemish control group at the level of dimensional Trait scores, number of criteria, and prevalence rates of personality disorder diagnoses. Unsurprisingly, higher scores at these levels were obtained within the psychiatric sample. The prevalence of an Axis II disorder was 12% in the Flemish and CFS samples, whereas the psychiatric sample obtained a prevalence of 54%.

The prominent absence of any significant difference in personality disorder characteristics between the female Flemish general population and the CFS samples seems to suggest only a minor etiological role for personality pathology, as defined by the DSM-IV Axis II, within CFS.