SUMMARY A stroke registry was established in Shibata City, Nilgata Prefecture, Japan (population 75,000) in 1976. WHO recommendations for criteria were followed. This paper reports stroke incidence for die initial 3 years of the registry: 1976 dirough 1978. All liring padents were examined clinically by a staff physician. Only patients with a diagnosis of first stroke were included in die study. Sensitivity of the referral system was estimated at 85 + %, comparable to that in American studies.Arerage annual incidence per 1,000 in residents ^20 years was 2.61 for all strokes (3.42 for males; 1.88 for females), 0.20 for subarachnoid hemorrhage, 0.61 for cerebral hemorrhage, 1.51 for cerebral infarctionrates similar to those reported 10-20 years previously for the United States.The male-female ratio STROKE has been the leading cause of death in Japan since 1951.1 -* According to international comparisons, Japan has the highest mortality rate from stroke of any developed country.'"* Because mortality rates can be affected by factors such as access to medical care and survival, incidence is a more reliable measure of frequency. There have been few reports, however, on the incidence of stroke in Japan. Incidence rates would be helpful for studying the natural history of the disease and for developing appropriate health care facilities. To meet this need, a stroke registry was developed in Shibata, Niigata Prefecture, Japan, beginning in 1976. This paper presents data from the stroke registry during the initial 3-year period and compares the incidence rate in Shibata with incidence rates recorded from other areas of Japan and from the United States.
Methods
Study PopulationShibata was selected as the city in which to develop a registry because Niigata Prefecture has one of the highest age-adjusted death rates from stroke in Japan." The city of Shibata covers an area of 434 square kilometers and is located in the northern part of the prefecture ( fig. 1). Shibata includes a central From the Department of Public Health, Osaka City University Medical School, 1-4-54 Asahi-Machi Abeno-Ku, Osaka 545, Japan (Drs. Tanaka, Ueda, Yamashita, Owada, Messers Date, Baba, Hayashi, and Shoji). Niigata-Ken Medical Association, Niigata, 961 Japan (Dr. K-I Baba). Shibata-Shi, Toyosaka-Shi, KitaKambara-Gun Medical Association, Shibata, 957 Japan (Dr. Shibuya). The Department of Public Health, City of Shibata, Shibata, 957 Japan (Dr. Kon). Division of Epidemiology, School of Public Health, University of California, Los Angeles, CA 90024 (Dr. Detels).Reprints: Dr. Tanaka, Dept. Public Health, Osaka City University Medical School, 1-4-54 Asahi-Machi Abcno-ku, Osaka, 545 Japan.