Global Associations of the Traditional Japanese Diet Score with Hypertension Prevalence and Systolic Blood Pressure from 2009 to 2019: A Cross-Sectional and Longitudinal Ecological Study.

Objective: Prevention and improvement of hypertension is one of the most important health issues worldwide. The traditional Japanese diet contributes to the prevention of some non-communicable diseases associated with hypertension. However, whether traditional Japanese dietary patterns are associated with hypertension prevalence and systolic blood pressure (SBP) worldwide remains unknown. In this study, we aimed to investigate whether the traditional Japanese diet score (TJDS) is associated with hypertension prevalence and SBP.

Methods: This cross-sectional and longitudinal ecological study from 2009 to 2019 included 141 countries with a population of at least 1 million. All data used for analysis were obtained from internationally available databases. The TJDS was calculated using country-specific supplies of five foods commonly eaten in the traditional Japanese diet (rice, fish, soybean, vegetables, and egg) and three less commonly eaten foods (wheat, milk, and red meat). Hypertension was defined by SBP ≥140 mmHg, diastolic blood pressure ≥90 mmHg, or use of antihypertensive medications. The mean SBP was >25 age-standardized data. A general linear model was used for the cross-sectional model in 2009, and a linear mixed model was used for the longitudinal analysis from 2009 to 2019. The covariates included gross domestic product, percentage of population aged >65 years, years of education, smoking rate, average body mass index, physical activity, and energy supply.

Results: The TJDS was negatively associated with hypertension prevalence (β ± standard error: -0.861 ± 0.202, p < 0.001) and SBP (β ± standard error: -0.364 ± 0.154, p < 0.05) in the cross-sectional analysis. The TJDS was significantly negatively associated with hypertension prevalence (β ± standard error: -0.845 ± 0.200, p < 0.001) and SBP (β ± standard error: -0.312 ± 0.149, p < 0.05) in the 10-year longitudinal analysis controlled for full covariables.

Conclusions: Traditional Japanese dietary patterns are associated with lower hypertension prevalence and SBP worldwide.