To explore a combination of health-related psychobehavioral features as potential positive criteria for somatoform disorders (SFD). Currently, SFD can only be diagnosed in the absence of sufficient organic symptom explanation, resulting in low criterion validity and delay of appropriate therapy.
Cross sectionally, we studied various psychobehavioral characteristics of 197 inpatients with suspected allergies. At the beginning of the medical work-up, patients were interviewed and completed a set of self-rating questionnaires (Illness Perception Questionnaire-Revised, Whiteley Index-7, Cognitions About Body And Health Questionnaire, Scale for the Assessment of Illness Questionnaire, Health Attitude Survey, Reassurance Questionnaire, and Patient Health Questionnaire). Organic explicability of the presenting symptoms was assessed by allergists at the end of the work-up. Forty-eight patients with SFD were compared with 149 patients without SFD, and predictive models were set up. To control for effects of the work-up situation, we also investigated 47 patients with an established diagnosis of hymenoptera venom allergy.
In the work-up group, various self-reported psychobehavioral features discriminated patients with SFD from patients without SFD. In logistic regression analysis, self-reported dissatisfaction with medical care, disease conviction, reduced symptom controllability, and reduced body scanning independently predicted SFD. A predictive model based on these psychobehavioral characteristics had high sensitivity and specificity (area under the curve = 0.86, 95% Confidence Interval = 0.79–0.93; p < .001), which was comparable to the Patient Health Questionnaire-15, an established SFD screening tool assessing somatization.
Psychobehavioral characteristics in patients with SFD cannot solely be attributed to the uncertainty of a work-up situation. Their predictive value is comparable to that of the traditional measuring of symptom number and severity; hence, they should be considered as SFD positive criteria in Diagnostic and Statistic Manual of Mental Disorders, 5th Edition.
SFD = somatoform disorder; VIT = venom immunotherapy; DSM-IV = Diagnostic and Statistic Manual of Mental Disorders, 4th Edition; SCID = Structured Clinical Interview for DSM-IV; PHQ = Patient Health Questionnaire; GAD = general anxiety disorder; IPQ-R = Illness Perception Questionnaire-Revised; WI = Whiteley Index; CABAH = Cognitions About Body And Health Questionnaire; SAIB = Scale for the Assessment of Illness Questionnaire; HAS = Health Attitude Survey; RQ = Reassurance Questionnaire; TUM = Technische Universitaet Muenchen.
From the Departments of Psychosomatic Medicine and Psychotherapy (C.H., E.B., S.G., C.L., D.H.), Psychiatry and Psychotherapy (S.B.), Dermatology and Allergy (M.G., B.E., J.R.), GA2LEN (Global Allergy and Asthma European Network) Excellence Centre, Clinical Toxicology (F.E.), and the Department of Internal Medicine, Technische Universitaet Muenchen (TUM), Munich, Germany; Department of Psychosomatic Medicine and Psychotherapy (B.L.), Universitaetsklinikum Hamburg-Eppendorf and Klinikum Eilbek, Hamburg, Germany; Division of Environmental Dermatology and Allergy (J.R.), Helmholtz Center Munich for Environmental Health/TUM, Munich, Germany; and the Department of Psychosomatic Medicine and Psychotherapy (D.H.), Klinikum Harlaching, Munich, Germany.
Address correspondence and reprint requests to Constanze Hausteiner, Klinik und Poliklinik für Psychosomatische Medizin und Psychotherapie, Klinikum rechts der Isar der Technischen Universitaet Muenchen, Langerstraße 3, 81675 Muenchen, Germany. E-mail: firstname.lastname@example.org
The study has been funded by a grant from the Committee for Clinical Research (KKF) of the Medical Faculty, TUM. C.H., S.B., and M.G. received payment from this grant according to their contributions to the study. None of the authors has any potential conflicts of interest.
Received for publication September 9, 2008; revision received June 19, 2009.