Spatial concentration of the incidence of treated psychiatric disorders in Mannheim

The spatial concentration of the incidence of treated psychiatric disorders in Mannheim was determined in 2 ways. The first, the classical zone model according to Neller (1), distinguishes an inner, intermediate and outer zone. This concept was applied to data from an ecological study conducted by Häfner et al. (2) in 1965 and to those derived from the Cumulative Psychiatric Case Register for the years 1974-1980. For the second period of time we developed, in addition, a factor ecological concept. The 23 districts of Mannheim were divided into 5 areas that were as homogeneous as possible in terms of segregation and density. There was a marked increase in the concentration index for schizophrenia in the inner zone, as well as for neuroses and personality disorders between 1974-1980 as compared with 1965. There were strong concentrations in the inner zone during both periods of study for the diagnosis of alcoholism and drug addiction. Although in 1965 there was a visible concentration trend in the inner zone for affective psychoses, it had almost vanished between 1974-1980. Using the factor ecological classification we demonstrated that, with the exception of affective psychoses and neurotic depression, all diseases concentrate in the city areas that, besides being centrally located, are characterized by high population density, poor housing conditions, low social status of the residents and where foreign nationals were segregated in the 1970s.