Developing and validating a diagnostic threshold for central blood pressure in assessing cardiovascular risks

AIMS: This study aimed to establish an outcome-derived threshold for central blood pressure (cBP) and evaluate its clinical utility in stratifying cardiovascular (CVD) risk. METHODS AND RESULTS: A retrospective cohort study of 34 289 adults without prior CVD was conducted using the UK Biobank dataset. The primary endpoint was a composite of cardiovascular mortality and non-fatal cardiovascular events. Diagnostic threshold for cBP was developed by bootstrap and approximation methods, based on the current brachial BP. Cox regression models were employed to evaluate the clinical utility of diagnostic thresholds for cBP in predicting in CVD. A diagnostic threshold of 135 mmHg for central systolic blood pressure (SBP) corresponded to the threshold of 140 mmHg for brachial SBP. Simultaneous assessment of brachial and central SBP configurated following categories: brachial and central normotension (49.84%), isolated brachial hypertension (2.23%), isolated central hypertension (3.65%) and concordant brachial and central hypertension (44.28%). Compared with concordant normotension, hazard ratios for cardiovascular events were 0.81 (0.45, 1.44) for isolated brachial hypertension, 1.70 (1.23, 2.35) for isolated central hypertension and 1.51 (1.30, 1.76) for concordant hypertension. The inclusion of cBP improved model fit and discrimination for predicting CVD beyond brachial BP alone. CONCLUSION: This study established a diagnostic threshold of 135 mmHg for central SBP. Individuals with central HT exhibited elevated risks of CVD, regardless of brachial HT status. Incorporating central BP enhanced the prediction of CVD risk beyond traditional BP measurement alone.