Approche épidémiologique du trouble délirant, à propos de 66 cas

Abstract

In theory, delusional disorder (according to the DSM-IV criteria) is considered to be rare. Its prevalence is close to 0.03%. In practice, this disorder seems to be encountered more frequently than assumed. However, it does not seem to be properly diagnosed at the beginning and this may lead to dramatic consequences. The aim of our study was to make an epidemiological approach to delusional disorder and to find clinical items that could guide to earlier diagnoses. This consisted in a comparative survey of the cases met in a psychiatric service in the Sfax Teaching Hospital in Tunisia. We carried out a retrospective epidemiological study of 66 delusional disorder cases according to DSM-IV criteria. We compared them to a group of 130 patients with other psychiatric disorders. The statistical analysis involved three types of study. First we elaborated a descriptive study of delusional disorder patients. Second, a comparative single variable analysis to pinpoint delusional disorder related items. And finally we made a multiple variable analysis using a logistic regression to identify the most discriminating items of the disease. The delusional disorder group was composed of 53 males and 13 females. For most patients, the educational level was low and the professional situation was poor. The main themes were: persecution (47%) and jealousy (21.2%). The rate of paranoiac personality was 90.9% and that of those who had committed forensic acts was 42.4%. The main initial diagnoses were minor depressive disorder for 40.9% and schizophrenia for 24.2% of cases. The average delay to establish the correct diagnosis was about five years after the first psychiatric examination. According to the single variable analysis, the items statistically related to delusional disorder were: age at the moment of the last diagnosis, marital status (single; divorced), professional qualification, somatic complaints, reported psychosocial stress, no cure requests, the initially prescribed treatment (more often anti-depressant and tranquillizer, and less often neuroleptic), irregular follow-up, dissatisfaction with the outcome under the initial treatment, no compliance with treatment, forensic acts committed ( P < 0.001 for each item), instinctive-affective complaints ( P < 0.01) and the instruction level (higher level) ( P < 0.05). There were no statistical differences concerning sex, residence area (urban or rural), regularity of professional activity and socioeconomic level. The multiple variable analysis revealed that, regardless of the other variables, patients with delusional disorder were distinguished from those of the other group by not asking for care and by expressing dissatisfaction with the outcome of the initial treatment ( P < 0.001 for the two items). These two items could be useful to orientate an early diagnosis of delusional disorder within a given socio-cultural environment, namely in cases of the frequently encountered minor depressive disorder.