Hisayama Study

Background/Questions

Shibanosuke Katsuki, professor in the Second Department of Internal medicine at Kyushu University, started the broad-based Hisayama community study in a cohort in 1961 that has continued for 44 years and is currently being followed up by Teruo Omae, Masatoshi Fujishima, and Mitsuo Iida. (The past and current head of the Division of Epidemiology are Kazuo Ueda and Yukata Kiyohara.) The main intent was initially description of the health and disease of the community. Hisayama is unique in having maintained traditional agricultural practices, resisted industrialization, and remained stable in population compared to towns in other regions. Hisayama has similar male to female ratios and age distributions to the national average.

When the research began, there was a general distrust of the medical profession of Japan, and many doubted the competency of doctors. During that era, the transport of stroke patients was prohibited in Japan, and it was 10 years before CT scanning was routinely used for the diagnosis of cerebrovascular disease. Therefore, research into the accuracy of diagnosis of cerebrovascular disease was an important priority.

Methods/Design

The unique method features of this study include high rates of medical examinations, autopsies in 80% or more than 1,800 cases, and follow-up of 99% of the cohort of people greater than age 40. The study has been passed down among four professors of internal medicine, four mayors and four (now three) local medical practices and involved close teamwork among the university, local offices, and local medical practices, as well as the trust of townspeople. There is no other epidemiological study of a community that has such a thorough postmortem database being used to investigate correlations with lifestyle-related diseases. The department of Pathology at Kyushu University made this unique contribution.

Results

Highlights from 40 years of the Hisayama study:

• The accuracy of diagnosing cerebrovascular disease, heart disease and malignancies was validated with postmortem findings, along with trends in disease profiles.
• A correction was made of the over-diagnosis of cerebral hemorrhage and under-diagnosis of brain infarction.
• The risk factors for cardiovascular disease and their change over time were established
• The distribution was reexamined of atherosclerosis in cerebral, and coronary arteries, and the aorta.
• Trends in lifestyle-related diseases were made in different geographic sites and over time.
• The prevalence and trends of various types of dementia were established.
• Age and gender differences in laboratory reference values were established.

(H. Ueshima)