Age- and sex-related reference values for central blood pressure parameters in middle-aged and older Japanese adults: the Wakayama study

Central blood pressure (BP) is more strongly associated with cardiovascular events than brachial BP. Few studies have described age-related changes in central BP in the general Japanese population. This study aimed to provide reference values for central BP parameters according to the age and sex, using data from 2964 participants aged 40–89 years (mean age: 60 years) who had no history of overt cardiovascular or chronic kidney disease and had not received antihypertensive, lipid-lowering, or hypoglycemic treatments. The central aortic pressure waveform was measured noninvasively by pulse wave analysis using the SphygmoCor XCEL operating system. Central systolic BP (cSBP), pulse pressure (cPP), and augmentation pressure (AP) exhibited a curvilinear relationship with age, with men having significantly higher cSBP but lower cPP and AP than women (cSBP: 132 mmHg vs. 123 mmHg, P < 0.001; cPP, 50 mmHg vs. 55 mmHg, P = 0.001; and AP: 24 mmHg vs. 32 mmHg, P = 0.002). Reference percentiles for cSBP, cPP, and AP were determined for each 5-year age group using the LMS method. Multiple regression analyses showed that age-standardized z-scores for cSBP, cPP, and AP were significantly associated with hypertension, dyslipidemia, diabetes mellitus, abdominal obesity, and heavy smoking, after adjusting for potential confounders. In conclusion, this study provides age- and sex-specific percentiles of central BP parameters in middle-aged and older Japanese adults. These reference values allow a more accurate interpretation of results and may be useful for diagnosis and management of hypertension in clinical practice and for risk stratification in population studies.