Objective: To determine the prevalence of psychological disorders and addiction problems amongst homeless people in Utrecht, the Netherlands.
Design: Descriptive cross-sectional study.
Method: In 1998, the Trimbos Institute in Utrecht held 150 interviews with adult homeless people by means of a random sample taken from six centres for the homeless. The following screening instruments were used to determine the prevalence of a depressive episode, schizophrenia and other non-affective psychotic disorders, an antisocial personality disorder and an alcohol or drugs dependency/abuse problem: the depression screener from Schrijvers et al., the schizophrenia section from the Composite International Diagnostic Interview (CIDI) a modified questionnaire from Schrijvers, related to the DSM-III-R, about aggressive behaviour and the Addiction severity index, European variant, version III. By means of comparative research, optimum threshold values for the presence of the aforementioned disorders were determined with respect to extensive diagnostic interviews that were taken to be the gold standard.
Results: In the homeless population studied (n = 150 (response: 68%); 138 men and 12 women) 32% had a more narrowly defined form of depression, 15% a schizophrenic disorder (DSM-III-R-codes 295.00-295.70) and 52% an antisocial personality disorder. In the case of depression and schizophrenia it concerned a 6-month prevalence and in the case of antisocial personality disorders it concerned the lifetime prevalence. The lifetime prevalence of alcohol dependence or abuse was 59% in the population studied (n = 131) and the monthly prevalence was 22%. The lifetime prevalence of drug dependence or misuse was established to be 76% and the monthly prevalence 54%. The prevalences were high in comparison with international figures. A so-called double diagnosis was identified for 27% of the homeless population.
Conclusion: Homeless people in Utrecht suffer from a poor mental health.