Socioeconomic indicators and cardiovascular disease incidence among Japanese community residents: the Jichi Medical School Cohort Study.
BACKGROUND
There has been little research in inequalities in risk of cardiovascular disease incidence by social class in Asia.


OBJECTIVE
The purpose of this study was to examine the association between socioeconomic indicators and risk of stroke and coronary heart disease in Japan.


METHODS
Data from the Jichi Medical School Study, a population-based prospective cohort study of approximately 11,000 Japanese men and women, were used. The average follow-up period was 11.7 years. Age- and area-adjusted hazard ratios with 95% confidence intervals (CIs) for education level/occupation were calculated using Cox proportional hazard regression analysis.


RESULTS
Compared to those who completed education at age 14 or younger, the age and area-adjusted hazard ratios of intraparenchymal hemorrhage incidence for men who completed education at age 15-17 and at age 18 or older were 0.42 (95% CI, 0.21-0.84) and 0.34 (95% CI, 0.14-0.84), respectively. The age- and area-adjusted hazard ratios of intraparenchymal hemorrhage and subarachnoid hemorrhage incidence for female white-collar workers compared to female blue-collar workers were 0.28 (95% CI, 0.08-0.98) and 3.23 (95% CI, 1.29, 8.01), respectively. No associations were found between education level and risk of coronary heart disease among both men and women.


CONCLUSIONS
These results suggest the pattern of social inequalities in health in Japan might be different from that in Western countries.
Honjo
Kaori
K
Public Health, Department of Social and Environmental Medicine, Graduate School of Medicine, Osaka University, Suita, Osaka, Japan. khonjyo@pbhel.med.osaka-u.ac.jp
Tsutsumi
Akizumi
A
Kayaba
Kazunori
K
D000328:Adult; D000368:Aged; D002318:Cardiovascular Diseases / Q000453:epidemiology*; D015331:Cohort Studies; D003327:Coronary Disease / Q000453:epidemiology*; D004493:Education / Q000706:statistics & numerical data*; D004522:Educational Status; D005260:Female; D006801:Humans; D020300:Intracranial Hemorrhages / Q000453:epidemiology*; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012307:Risk Factors; D012737:Sex Factors; D012959:Socioeconomic Factors; D020521:Stroke / Q000453:epidemiology*