Alexithymia and personality in patients with anxiety disorders and major depression: effects on treatment outcome

Objectives Alexithymia is frequently associated with major depression and anxiety disorders, and in the literature it is considered as a negative prognostic factor in the treatment of these disorders. Nevertheless, limited evidence is available about the effect of alexithymia on treatment outcome. In this study, we analyze the presence of alexithymia in patients with depressive or anxiety disorders. In addition, we investigate the effects of alexithymia considered as a single factor, and the interaction between alexithymia and socio-demographics and clinical variables (personality traits) as modulators of response to combined treatment. Materials and methods Eighteen outpatients with major depression or anxiety disorders underwent pharmacotherapy and individual psychodynamic psychotherapy. Subjects were assessed using the Hamilton Rating Scale for Depression (HAM-D), the Hamilton Rating Scale for Anxiety (HAM-A) and the Toronto Alexithymia Scale 20-item (TAS-20) at baseline and after eight weeks of treatment. Personality traits were assessed with the SCID II at baseline. Outcome was the change in scores of HAM-D and HAM-A from baseline to the eight weeks of treatment. Predictor was the TAS score. The statistical relationship between outcome and predictor was analyzed by linear regression. In the regression model, we included stratification factors (socio-demographics and clinical variables) as covariates if they had a significant statistic relationship with the main outcome and their interaction with the main outcome is included. Results After eight weeks of treatment, we observed an improvement of 78% on HAM-D and of 69% on HAM-A, while 55.5% of subjects were not alexithymic, 22.2% were borderline alexithymic and 5.5% were diagnosed as alexithymic. No significant effect resulted from the analysis of alexithymia as a modulator of response to anxiety or depressive symptoms. On the other hand, the combination of alexithymia with "older age" predicted worse outcome by the HAM-D (p = 0.02873). Moreover, we observed a negative correlation between "obsessivecompulsive personality traits" and improvement on HAM-D (p = 0.002314), and a positive correlation between alexithymia and obsessive-compulsive personality traits (p = 0.02629). Conclusions Alexithymia may interfere with response to treatment in subjects with depressive or anxiety disorders when combined with other socio-demographic and clinical variables. Further research is mandatory to confirm these results.