Background: The United States and Japan have similar standards of living, healthcare systems, and industrializations but exhibit markedly divergent life expectancies both at birth and at later ages (50 or 65 years old). Arterial stiffness has been widely regarded as a barometer of biological or physiological aging and could provide insight into the inter-country differences.
Objectives: To determine whether the increases in arterial stiffness across the adult age range are greater in U.S. than Japanese adults.
Design: Cross-sectional analyses.
Setting: Laboratory-based study.
Participants: Healthy, nonsmoking Japanese (n = 400) and U.S. (n = 400) adults without cardiovascular and other chronic diseases.
Measurements: Indices of arterial stiffness, including carotid-femoral (cfPWV) and brachial-ankle pulse wave velocity (baPWV) were measured, along with a variety of ancillary measures. The recruitment method, measurement technique, and protocol were standardized and identical between U.S. and Japanese facilities.
Results: cfPWV and baPWV increased progressively with advancing age in all subgroups (stratified according to sex and country). The rates of age-related increases in arterial stiffness were not different between U.S. and Japanese men, but age-associated increases in cfPWV were significantly greater in U.S. than Japanese women, widening the intercountry differences at older age ranges.
Conclusion: Japanese women had smaller increases in central arterial stiffness with advancing age than U.S. women.
Keywords: aging; international; life expectancy; pulse wave velocity.
© 2015, Copyright the Authors Journal compilation © 2015, The American Geriatrics Society.