High prevalence of personality disorders among circadian rhythm sleep disorders (CRSD) patients.

The purpose of this study was to examine systematically our previous clinical impression regarding the prevalence of personality disorders in patients suffering from circadian rhythm sleep disorders (CRSD). We hypothesized that, in a group of patients suffering from CRSD, there would be a higher frequency of personality disorders than in a group of healthy controls. The experimental group consisted of CRSD patients diagnosed according to a clinical interview and actigraphic recordings. The control group consisted of healthy volunteers in whom CRSD had been ruled out by means of a self-administered questionnaire. Both groups were assessed for personality disorders using the MCMI, a diagnostic tool based on Millon's biopsychosocial theory of personality and the PRQ-R, a diagnostic tool based on the DMS-III-R. Both tests provided clear and significant support for the hypothesis that individuals suffering from CRSD are characterized to a greater extent by personality disorders than a control group. No specific characteristic pattern or profile of personality disorders was clearly detected. Correct early diagnosis and treatment of CRSD may improve afflicted individuals' adaptive capabilities and perhaps even prevent the development of a personality disorder. This suggests how important a greater awareness of CRSD on the part of the professional community may be.