Catastrophizing misinterpretations predict somatoform-related symptoms and new onsets of somatoform disorders.

BACKGROUND Somatoform disorders are characterized by multiple recurring symptoms that resemble physical illnesses but defy medical explanation. Psychological models suggest that catastrophizing misinterpretations of harmless physical symptoms play a key role. However, the question of whether such biases predict somatoform-related symptoms and the onset of somatoform disorders has not been adressed. Hence, the aim of the present study was to further advance our understanding of the role of catastrophizing misinterpretations in somatoform disorders. METHODS In the present study, we used data from the Dresden Predictor Study (N=1538), in which an epidemiologic sample of young German women was tested at two time points approximately 17 months apart. Each participant completed a diagnostic interview, an interpretation questionnaire for somatoform and hypochondriacal symptoms, and three measures of such symptomatology: somatization subscale of the Symptom Checklist-90-Revised (SCL-90-R), Whiteley Index (WI), Body Sensations Questionnaire (BSQ). RESULTS At follow-up, 33 women were diagnosed with new onsets of lifetime somatoform disorder. Results showed that catastrophizing misinterpretations assessed at baseline were predictive of somatoform-related symptoms at follow-up, i.e., symptoms assessed with the WI and BSQ. Moreover, catastrophizing misinterpretations were predictive of new onsets of somatoform disorders, even after controlling for general threat-related misinterpretations and indices of somatoform symptoms (i.e., SCL-90-R and BSQ). CONCLUSIONS This is the first prospective, longitudinal study to demonstrate that catastrophizing misinterpretations have incremental validity as predictors of future somatoform-related symptomatology and somatoform disorders.