Comparative studies of diet-related factors and blood pressure among Chinese and Japanese: Results from the China-Japan Cooperative Research of the WHO-CARDIAC Study

We aimed to compare the differences in diet-related factors and their assoc iations with blood pressure (BP) between Chinese and Japanese. A total of 1 ,151 Chinese (MIF: 551/600) and 1,681 Japanese (782/899), aged 48-56 years, were studied using a multi-center cross sectional study design. This work was a constituent part of the World Health Organization(WHO) Cardiovascular Disease and Alimentary Comparison (CARDIAC) Study. Measurements included i n the present report were BP, body mass index (BMI), serum total cholestero l (TC), 24-h urinary sodium, potassium, calcium, magnesium, creatinine, 3-M ethylhistidine (3MH, a marker of animal protein intake) and taurine (a mark er of seafood intake) excretion levels. Results were as follows: (a) Japane se men had a significantly higher prevalence of hypertension than the Chine se (34.4% vs. 20.5%, p<0.01). After adjustment for age, Japanese men had a significantly higher mean systolic and diastolic BP(SBP, DBP), and Japanese women had a significantly higher DBP than the Chinese subjects overall (p< 0.01, respectively). (b) Japanese had significantly higher mean BMI, TC and sodium excretion, and lower mean magnesium excretion than Chinese (p<0.01) , (c) In the Japanese sample, multiple linear regression analyses (using a stepwise procedure) showed that SEP had a significant positive association with BMI and sodium excretion, and a significant negative association with magnesium excretion, while DBP had a significant positive association with BMI and a significant negative association with the 3MH to creatinine ratio (3MH/Cre), In the Chinese sample, both SEP and DBP showed a significant pos itive association with BMI and sodium, and a significant negative associati on with 3MH/Cre. In conclusion, Japanese had significantly higher mean BP t han Chinese. The differences in BP may have been partly attributable to dif ferences in various diet-related factors, particularly in BMI, sodium, magn esium-rich foods and animal protein intake, between the two populations.