[The mentally retarded in the local community--occurrence, causes, medical treatment and follow-up].

An epidemiological study of mentally retarded persons in a Norwegian municipality was carried out in order to collect data about prevalence, causes, medical treatment and follow-up. The number of mentally retarded was found to be twice the average for the country as a whole. The causes of mental retardation indicated that this was due to a low degree of urbanization--a stable population, larger families, more births at home and long distance from hospital. The survey revealed that medical care had been seriously neglected. Several patients had never been given a diagnosis, and the number of contacts with a doctor for any reason was far below the average for the rest of the local population. Several were found to have unknown impaired vision and hearing, and many were being inadequately treated for common diseases like migraine, myalgia, stomach pain, diarrhoea etc. The neglect was worse among those living at home than among those living in the institutions for the mentally retarded.