Ecological pattern of first admitted schizophrenics in two German cities over 25 years

Ecological studies on the distribution of rates of first-admitted schizophr enics were carried out in Mannheim in 1965 and from 1974 to 1980. As the ca tchment area of the ABC Schizophrenia Study comprises the cities of Mannhei m and Heidelberg, we were able to conduct a third ecological study for Mann heim and a first study for Heidelberg covering the years 1987 to 1989. High rates of schizophrenic residents are found in the inner districts of M annheim and Heidelberg. This concentration has been stable over a period of 25 years for Mannheim. Subdividing the districts of Mannheim and Heidelber g into zones, only in Heidelberg and only for the second cross-section in M annheim, the rates decreased constantly with increasing distance from the c entre. Summing up the districts of Mannheim and Heidelberg in homogenous ar eas on the basis of economical and socio-demographic properties, high rates of schizophrenics were found in homogenous areas with poor and unfavourabl e living conditions. In Mannheim and Heidelberg, homogenous areas with the highest rates of schizophrenics are characterised by highly unfavourable li ving conditions, a high percentage of young men, people living alone, stude nts, foreigners, people with a low level of education and a high immigratio n/emigration rate. The analysis on the individual level, i.e. in the biogra phy of schizophrenics shows that processes of social drift and/or nonstarte r take place long before first admission in the prodromal phase and the psy chotic prephase of beginning schizophrenia. Probably, these selective proce sses like downward drift or nonstarting processes, lead to the migration of schizophrenics into unfavourable areas or schizophrenic residents staying in poor areas, while healthy residents leave these districts. Selective pro cesses such as help seeking behaviour and access to the care system have no effect on the unequal distribution. In summary, a definite confirmation or refutation of one of the two causal hypotheses, 'social selection' vs. 'so cial causation', is not possible up to date, but the empirical results supp ort the selective hypothesis for schizophrenic disorders. (C) 1999 Publishe d by Elsevier Science Ltd. All rights reserved.