[Epidemiological study of schizophrenia on the Island of Tsushima in Nagasaki Prefecture].
The epidemiology of schizophrenia has been studied with regard to the incidence, prevalence, and morbid risk, and there have been comprehensive reviews. However, the incidence and prevalence have not been analyzed simultaneously in many studies. In the present study, which was performed on a remote island, the number of patients could be determined, and they could be followed up by the same observer. This permitted us to conduct comprehensive epidemiological research while providing local mental health care. The subjects were patients diagnosed with schizophrenia according to the DSM-III-R in Tsushima, Nagasaki Prefecture, between April 1, 1988 and March 31, 1996. The incidence of schizophrenia was 2.3 (2.5 in males, 2.1 in females) per 10,000 people of the population, and the age-adjusted incidence was 2.4. Its prevalence was 5.8 (6.1 in males, 5.7 in females) per 1,000 people of the population, and the age adjusted prevalence was 6.2. In both sexes, the number of patients and the prevalence increased annually. The morbid risk was 0.95% (1. 01% in males, 0.89% in females) by the direct method (calculated from the incidence) and 0.85% (0.90% in males, 0.81% in females) by the indirect method (calculated from the prevalence), showing similarity. These incidence, prevalence, and morbid risk results did not markedly differ from the values reported to date. It is important to establish preventive measures for schizophrenia on the basis of the basic data obtained in this study, and to serially evaluate changes in epidemiological parameters of schizophrenia after their application. Furthermore, by comparing these epidemiological findings with those of other mental disorders and other regions, methods are expected to be utilized comprehensively for local mental health care.
Hamada
Yoshito
Y
Sonoda Hospital.
Ohta
Yasuyuki
Y
Nakane
Yoshibumi
Y
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012559:Schizophrenia / Q000453:epidemiology*