Genetics and delusional disorder
ABSTRACT This article gives an overview of genetic research approaches and their application to delusional disorder. Most studies have been based on small samples and have had other methodological limitations, so it is not clear whether there is a genetic contribution to the aetiology of delusional disorder. It is unlikely that delusional disorder is strongly related genetically to affective disorder or schizophrenia, but more subtle relationships cannot be ruled out. The rarity of multiply affected families prohibits linkage studies and, to date, molecular genetic investigations have been mainly limited to small association studies of dopamine receptor polymorphisms. A range of considerably larger, epidemiologically rigorous studies is required, but the uncommonness and other features of the disorder put strong limitations on the prospects for ascertaining adequate samples. Copyright © 2006 John Wiley & Sons, Ltd.
- Advances in Psychiatric Treatment 01/2009; 15(1):40-48. DOI:10.1192/apt.bp.107.005421
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ABSTRACT: Neurocognitive accounts of delusion have traditionally highlighted perceptual misrepresentation, as the primary trigger in addition to other cognitive deficits that maintain the delusion. Here, a general neurocognitive model of delusional disorder (DSM-IV) is proposed, not so much based on perceptual or cognitive deficits after right hemisphere damage as on cognitive propensities, specifically excessive inferencing (especially jumping to conclusions) and excessive reference to the self, due to left hemisphere overactivity. The functional imaging, topographic EEG, and experimental imaging literatures on delusional disorder are reviewed, and 37 previously published cases of postunilateral lesion delusion (DSM-IV type, grandeur, persecution, jealousy, erotomania, or somatic), are reviewed and analysed multivariately. Functional imaging and EEG topography data were slightly more indicative of left hemisphere overactivity in delusional disorder. In addition, 73% of the postunilateral lesion cases (χ(2)=7.8, p=.005) of delusional disorder (DSM-IV type) had a right hemisphere lesion, whereas only 27% had a left hemisphere lesion. Left hemisphere release appears to be a more primary cause of delusional disorder than right hemisphere impairment, the latter merely entailing loss of inhibition of delusional beliefs. We propose that most patients with DSM-IV diagnoses of delusional disorder could be afflicted by excessive left hemisphere activity, but further research is necessary.Cognitive Neuropsychiatry 03/2010; 16(1):1-39. DOI:10.1080/13546800903442314 · 2.18 Impact Factor
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ABSTRACT: This article tries to give an answer to the question of whether International Classification of Diseases (ICD-10) persistent delusional disorder (PDD) or Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) delusional disorder (DD) is simply paranoid schizophrenia (PS). Because ICD-10 PDD and DSM-IV DD are identical, we use DD as a synonym. A prospective and longitudinal study compared all inpatients with DD treated at the Halle-Wittenberg university hospital during a 14-year period with a previously investigated selected cohort of patients with PS. Sociodemographic data, symptomatology, course, and outcome parameters were examined using standardized instruments. The duration of the follow-up period in patients with DD was 10.8 years and for the PS patients 12.9 years. Significant differences between DD and PS were found: DD patients are, in comparison to patients with PS, significantly older at onset. Less of their first-degree relatives have mental disorders. They less frequently come from a broken home situation. First-rank symptoms, relevant negative symptoms, and primary hallucinations did not occur in patients with DD. Patients with DD were less frequently hospitalized, and the duration of their hospitalization was shorter. Their outcome is much better regarding employment, early retirement due to the disorder, and psychopharmacological medication. They more often had stable heterosexual partnerships and were autarkic. They had lower scores in the Disability Assessment Scale and in Positive and Negative Syndrome Scale. The diagnosis of DD is very stable over time. The findings of this study support the assumption that DDs are a separate entity and only exceptionally can be a prodrome of schizophrenia.Schizophrenia Bulletin 11/2010; 38(3):561-8. DOI:10.1093/schbul/sbq125 · 8.61 Impact Factor