Illness perception in functional neurological disorder: low illness coherence and personal control.

Introduction: Illness perception refers to patients' subjective representations and appraisals of somatic and mental symptoms. These are relevant for self-management and outcome. In clinical practice, patients with functional neurological disorder (FND) often encounter a fragmented biomedical attitude, which leaves them without clear concepts. In this context, illness perception is relevant.

Methods: Illness perception was assessed in FND patients and compared with samples of psychosomatic patients (PSM) as well as poststroke patients (STR). The three samples (FND, n=87; PSM, n=97 and STR, n=92) were almost all in inpatient treatment or rehabilitation. Illness perception was assessed with the revised German version of the Illness Perception Questionnaire (IPQ-R). For assessments of correlations, depressive symptoms were tested with the Patient Health Questionnaire-9, dissociative and functional neurological symptoms by the German adaption of the Dissociative Experiences Scale and biopsychosocial complexity by the INTERMED Self-Assessment questionnaire.

Results: Apart from the chronicity subscale, all dimensions of the IPQ-R differed between groups. FND patients perceived lower illness coherence and personal control than both other groups and attributed their illness more to chance than to behavioural risk factors. PSM patients had the strongest emotional representations. There were only few correlations with dissociative scores and biopsychosocial complexity.

Conclusion: Illness perception is an important issue in patients with FND with particular emphasis on low illness coherence and personal control. Missing associations with biopsychosocial complexity suggest that subjective illness perception is an important complementary but separate issue, which likely influences therapeutic alliance and self-management in FND. Future studies should assess its influences on outcome.

Trial Registration Number: DRKS00024685; German Clinical Trials Register; www.drks.de.