The geographical mobility of severely mentally ill residents in London.
BACKGROUND: There is currently great concern over the demands on psychiatric services in metropolitan areas in most developed countries, and this is exemplified in capital cities. These greater demands were not anticipated by those planning psychiatric services and the consequences have led to insufficient beds in many areas. We investigated the geographical mobility (the number of changes of address in the past 2 years) of patients presenting to services in greater London, to determine whether this might be a possible factor in the increased demand. METHOD: The geographical mobility of the severely mentally ill was determined by taking a random sample of all psychiatric admissions to hospitals serving residents in the London area over the calendar year of 1994 (n = 156) and an equivalent sample of patients in an established community mental health team (n = 74) in one area (Paddington). The extent of geographical movement was determined for the 2 years prior to interview. RESULTS: Greater geographical movement in the in-patient group was found for those living in inner London compared with outer London and for patients admitted to hospitals outside their catchment area. Twenty-eight percent of the in-patient sample had changed address in the year before admission (including 13% more than once) and 39% had changed address in the 2 years prior to admission. By contrast, the patients seen by the community psychiatric team were less than half as likely to have changed address over the previous year as the in-patients, and none of the community team's patients had changed address more than once over the previous year. The geographically mobile patients had significantly longer periods in hospital than geographically stable patients. CONCLUSION: Geographical mobility of psychiatric patients in London is high and is particularly marked for those presenting for in-patient treatment. These findings suggest that greater mobility could be one of the most important reasons for the higher than expected demands on psychiatric services and the difficulties in maintaining contact with patients in London in general and inner London in particular. More attention should be paid to geographical mobility as a predictor of psychiatric service use, and it is recommended that it is recorded regularly in information systems.