Are alexithymia, depression, and anxiety distinct constructs in affective disorders?

Objective: the present study was undertaken to gain a better insight into the relationship between alexithymia, anxiety, and depression. Two hypotheses were tested: (1) whether a depressive or anxiety disorder is associated with an elevation of one or more dimensions of alexithymia; and (2) whether alexithymia is an independent construct from depression and anxiety in patients with depressive or anxiety disorders.

Method: a total of 113 patients with depressive or anxiety disorders (DSM-IV) and 113 control subjects completed the 20-item version of the Toronto alexithymia scale (TAS-20) and the hospital anxiety and depression scale (HADS).

Results: the TAS-20 total score was higher in depressed and anxious patients than in controls. This finding mainly depended on an increased score for "difficulty identifying feelings"(DIF), and (only in depressed patients) on an increased score for "difficulty communicating feelings" (DCF). The factor analysis of the TAS-20 and HADS items showed that depression is a construct different from alexithymia, whereas some overlap exists between anxiety and DIF dimension.

Conclusion: our results suggest that in depressive and anxiety disorders, alexithymia and depression are separate constructs that may be closely related; in contrast, there are some overlaps between the DIF dimension and anxiety.