Is alexithymia related to negative symptoms of schizophrenia? A preliminary longitudinal study

Background: Alexithymic features are close to anhedonia, blunted affect, and alogia that are also characteristics of the negative symptoms of schizophrenia. This study aimed to evaluate whether alexithymia is associated with negative symptoms and is related to the change of schizophrenic symptoms over time. Sampling and Methods: A consecutive sample of 29 schizophrenic outpatients was evaluated at baseline and at 3, 6, and 12 months during appropriate treatment. They completed the Positive and Negative Syndrome Scale, the Montgomery and Asberg Depression Rating Scale, the Global Assessment of Functioning Scale, and the 20-item Toronto Alexithymia Scale at any time points. Results: The psychiatric scale scores showed significant symptom improvement over time but were unrelated to the alexithymia score that was instead stable over time. Hierarchical regression showed that the 20-item Toronto Alexithymia Scale at baseline was the sole predictor of alexithymia at 12 months, after controlling for psychopathology and psychological functioning. Conclusions: Alexithymia was unrelated to negative symptoms, suggesting it is an independent and separate construct from schizophrenia. As expected, the negative symptoms were associated instead with illness-related aspects of depression and psychosocial functioning. Caution should be expressed in generalization mainly because this study is limited by the small sample size.