Background: Previous studies have suggested an association between alexithymia and obsessive-compulsive disorder (OCD). However, it is unclear to which extent alexithymic traits in OCD patients reflect familial deficits in cognitively processing and communicating feelings that are also present in their first-degree relatives. This study investigates the hypotheses of an elevated level of alexithymia in subjects with OCD and their first-degree relatives compared to controls and their first-degree relatives.
Methods: 82 cases with OCD and 169 first-degree relatives were compared to 76 controls and 144 first-degree relatives from a German family study on OCD (GENOS). All subjects completed the 20-item Toronto Alexithymia Scale (TAS-20). Direct or family informant interviews were carried out with the German version of the Schedule for Affective Disorders and Schizophrenia - lifetime version for anxiety disorders (DSM-IV).
Results: OCD was associated with significantly higher scores of alexithymia. However, first-degree relatives of OCD cases and of controls did not differ in TAS-20 scores. In linear regression analyses, the TAS-20 total score showed significant intrafamilial associations within the families of control subjects but not within families of OCD cases.
Conclusion: OCD is a severe mental disorder that is associated independently from other current comorbid axis I disorders with deficits in identifying and expressing feelings. However, alexithymia does not represent a familial risk factor for OCD.