Age-dependent association of central blood pressure with cardiovascular outcomes: a cohort study involving 34 289 participants using the UK biobank

UK Biobank remains a useful large-scale, open access data source, which this paper exploits for central blood pressure (cBP), estimated by the validated Vicorder arm-cuff device. Note that cBP parameters were estimated from brachial S/DBP waveforms "self-calibrated to brachial SBP/DBP by applying a validated brachial-to-aortic transfer function." Here validation, or evaluation, still allows considerable variation in cBPs compared with simultaneous pressures recorded invasively, averaging −4 ± SD 7.4 mmHg. Using brachial S/DBP for calibration underestimates intra-arterial 'real cBP' by some 6mmHg (see their [17]), whereas mean BP performs better. The 'transfer function' may or may not help, as discussed in Jim Sharman's Artery Society paper [1]. We do not use the 'real' BP clinically, only brachial. So, what does this paper add? Although both central and brachial BPs predict outcomes, the claim is that cBP here performs better than routine brachial BP in predicting events only in those aged <65 years, after adjusting for a variety of standard risk factors and appropriate statistical analysis. Yet, the overall cSBP prediction, only moderate for <65 s anyway with an hazard ratio of 1.13 per 10 mmHg in SBP change, is only 1% better than with brachial and borderline significant – trivial. Differences for using central versus peripheral pulse pressure as predictors were marginally greater by some 4% than for the central-brachial SBP effect. However, tests for improved discriminative ability between either cSBP or cPP were not significant. In summary, until the vagaries of estimating central BP based on inevitable current brachial BP calibration are eliminated – and these methods are emerging [2,3] – to this commentator, central BP offers little of value over the hugely 'validated' brachial BP. Using arterial function measured as aortic pulse wave velocity is quite another and more valuable a matter – not available in UK Biobank. ACKNOWLEDGEMENTS Conflicts of interest Prof. Cruickshank was President of the Artery Society 2026–2018.