Christian Haasen

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BACKGROUND The last decade of the twentieth century has seen an unprecedented increase in the number of reports in the psychiatric literature documenting increased rates of psychotic illness among migrants in a range of European countries. In countries where high rates of immigration have been long-standing such as Britain and the Netherlands, these(More)
The present study investigated whether schizophrenic, unipolar depressive, and obsessive-compulsive psychiatric patients show a distinguishable profile in tasks considered sensitive to frontal lobe functioning. Three psychiatric samples, each comprising 25 patients with little symptomatic overlap, were compared to 70 healthy controls. Participants completed(More)
BACKGROUND While infections due to hepatitis B virus (HBV) and hepatitis C virus (HCV) have been well-studied in injection drug users (IDUs), hepatitis A virus (HAV) infection and coinfection with multiple hepatitis viruses have received less attention. METHODS Hepatitis serology as well as sociodemographic and drug-related parameters were explored in(More)
An increase in the use of cocaine and crack in several parts of Europe has raised the question whether this trend is similar to that of the USA in the 1980s. However, research in the field of cocaine use in Europe has been only sporadic. Therefore, a European multi-centre and multi-modal project was designed to study specific aspects of cocaine and crack(More)
AIM The study investigates patterns of cocaine powder and crack cocaine use of different groups in nine European cities. DESIGN, SETTING, PARTICIPANTS Multi-centre cross-sectional study conducted in Barcelona, Budapest, Dublin, Hamburg, London, Paris, Rome, Vienna, and Zurich. Data were collected by structured face-to-face interviews. The sample comprises(More)
AIMS Trials in Switzerland, the Netherlands and Spain have found that heroin-assisted treatment (HAT) as maintenance treatment for opioid-dependent patients reduces illicit drug use. A German trial also found diamorphine treatment to be superior to methadone treatment. The present study describes the association between 2 years of heroin treatment and(More)
OBJECTIVE Studies on drug dependence show a high prevalence of comorbidity with additional mental disorders. Comorbidity patients also show more poly-substance use and other psychosocial problems. This study analyzed the importance of comorbidity for the long-term course of opiate dependence. METHOD 350 opiate-dependent patients were examined at yearly(More)
The severity of traumatization seems to correlate with a more severe course of post-traumatic stress disorder (PTSD) (and other post-traumatic disorders), while firm belief systems have been found to be a protective factor against post-traumatic disorders. This study sought to determine the role of belief systems in the outcome of psychotherapy for(More)
OBJECTIVE Inconsistent findings have been reported concerning the level of dissociative symptoms and their relationship with childhood trauma in alcohol-dependent patients. The present study aimed to further examine the level of dissociation and the trauma-dissociation relationship in a sample of alcohol-dependent patients, taking potential mediating(More)
Past studies examining the prevalence of psychiatric disorders among migrants have described a higher rate of schizophrenia, whereas the only major German study found a lower rate. Considering the changed composition of migrants today, a new assessment has become necessary. All admission records of migrants to a psychiatric clinic in 1993 and 1994 were(More)