Objective: The purpose of this study was to investigate regional differences in the standard mortality ratio (SMR) and risk factors (including dietary habits) for stroke across the three regions of Ehime Prefecture - Toyo (east), Chuyo (central), and Nanyo (south).
Participants and methods: We obtained medical records derived from 956,979 medical examinations carried out at JA Ehime Kouseiren Medical Examination Centers between April 1994 and March 2006. We analyzed data from 132,090 subjects (Toyo - 47,654, Chuyo - 38,435, Nanyo - 46,001) who underwent their first medical examination during this period. To analyze differences between the three regions, we first calculated the SMR for stroke based on data from the Basic Residential Registers and Health Statistics Bureau. Secondly, we calculated significant differences in body mass index, systolic blood pressure (SBP), diastolic blood pressure (DBP), blood glucose (Glu), and total cholesterol (T-CHO). Thirdly, we used the Chi-square test to calculate significant differences in the percentage of subjects who consumed the following foods on a daily basis: rice, bread, eggs, fish, meat, vegetables, dairy products, and fruit juice.
Results: Despite the fact that regional differences in the SMR for stroke have been decreasing, in both men and women in Nanyo, the mean values for SBP and DBP were significantly higher and the mean value for T-CHO was significantly lower than in Toyo and Chuyo. In Nanyo, the percentage of subjects who consumed rice and fish (men and women), meat (men), and juice (women) on a daily basis was higher than in Toyo and Chuyo.
Conclusion: In Nanyo, higher SMR for stroke may be related to high SBP and DBP and low T-CHO. As background to these results, it is also thought that regional differences in dietary habits may have an influence.
Keywords: diet; health indicators; lifestyle; living environment; standard mortality ratio of stroke.