Conversion disorder: a problematic diagnosis
- 1Section of Cognitive Neuropsychiatry, Department of Psychological Medicine, Institute of Psychiatry, London, UK
- 2Department of Clinical Neurosciences, Western General Hospital, Edinburgh, UK
- 3Department of Psychological Medicine, Institute of Psychiatry, King's College London, Weston Education Centre, London, UK
- Correspondence to Dr R A A Kanaan, Department of Psychological Medicine, Institute of Psychiatry, King's College London, Weston Education Centre, London SE5 9RJ, UK;
Contributors All authors participated in the conception and writing of this paper.
- Received 20 November 2009
- Revised 5 March 2010
- Accepted 15 April 2010
- Published Online First 29 October 2010
The diagnosis of conversion disorder is problematic. Since doctors have conceptually and practically differentiated the symptoms from neurological (‘organic’) disease it has been presumed to be a psychological disorder, but the psychological mechanism, and how this differs from feigning (conscious simulation), has remained elusive. Although misdiagnosis of neurological disease as conversion disorder is uncommon, it remains a concern for clinicians, particularly for psychiatrists who may be unaware of the positive ways in which neurologists can exclude organic disease. The diagnosis is anomalous in psychiatry in that current diagnostic systems require that feigning is excluded and that the symptoms can be explained psychologically. In practice, feigning is very difficult to either disprove or prove, and a psychological explanation cannot always be found. Studies of childhood and adult psychological precipitants have tended to support the relevance of stressful life events prior to symptom onset at the group level but they are not found in a substantial proportion of cases. These problems highlight serious theoretical and practical issues not just for the current diagnostic systems but for the concept of the disorder itself. Psychology, physiology and functional imaging techniques have been used in attempts to elucidate the neurobiology of conversion disorder and to differentiate it from feigning, but while intriguing results are emerging they can only be considered preliminary. Such work looks to a future that could refine our understanding of the disorder. However, until that time, the formal diagnostic requirement for associated psychological stressors and the exclusion of feigning are of limited clinical value. Simplified criteria are suggested which will also encourage cooperation between neurology and psychiatry in the management of these patients.
Funding RAAK was supported by the Wellcome Trust; TRJN was supported by the Medical Research Council.
Competing interests None.
Provenance and peer review Commissioned; externally peer reviewed.