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The Clinical and Sociodemographic Profile of Persistent Delusional Disorder

to fulfill the diagnostic criteria of persistent DD of the ICD-10 (F22) also fulfilled DSM-IV criteria for DD. Of the 61 patients clinically diagnosed as having persistent DD, 43 fulfilled the above criteria after reevaluation by the independent investigators. Thirty-three of these 43 patients took part in follow-up investigations including the Structured Clinical Interview for DSM-IV (SCID) [4] . The number of patients with DD (43) represents 0.43% of all inpatients, 0.90% of those with non-organic psychotic and non-organic affective disorders (ICD-10: F2, F3), and 2.12% of all patients with non-organic psychotic disorders treated at our institution during the study period. Although males were slightly more frequently represented (n = 22, 51.2%), the numbers were not significantly different from the gender distribution in all inpatients during the study period (4,904 males out of 9,969 patients; 49.2%; p = 0.796). In 23.3% of the patients, mental disorders in first-degree relatives were reported. Psychotic or major affective disorders were found in 11.6%, with major affective disorders being represented with 9.3% (4 patients) and psychotic disorders with only 2.3% (1 patient). Additional instruments included a semi-structured interview already used in earlier studies [5] for the assessment of demographic, sociobiological and clinical features; a symptom list derived from the Brief Psychiatric Rating Scale [6] and the Delusional disorder (DD) as defined by DSM-IV and ICD-10 was introduced by George Winokur [1] and first implemented in the DSM-III-R. It is almost identical with the Kraepelinian concept of paranoia at the beginning of the 20th century [2] . In earlier research, authors used their own diagnostic criteria with varying demarcations to other forms of non-organic paranoid syndromes. A generalization of results is therefore problematic. But also after the publication of DSM-IV and ICD-10, research on DD has been scarce. Aiming to contribute to the discussions in the preparation of ICD-11 and DSM-V, we initiated the Halle Delusional Syndromes (HADES) Study, a cross-sectional and longitudinal investigation comparing a sample of DD patients with patients having other non-organic psychotic disorders [3] . This letter reports data on prevalence, demographics, and social and clinical features of the index sample with DD. We identified all consecutive cases with a clinical discharge diagnosis of DD (n = 61) treated as inpatients at the Department of Psychiatry, Psychotherapy and Psychosomatics, Martin Luther University Halle-Wittenberg, Germany, from 1994 to 2008 (total number of inpatients = 9,969). Diagnoses were reviewed independently by the authors on the basis of a checklist consisting of the ICD-10 research criteria for persistent DD and the DSM-IV criteria for DD. All subjects who were confirmed Received: November 23, 2010 Accepted after revision: August 22, 2011 Published online: March 22, 2012