CHANGES IN STANDARD CUFF AND CENTRAL BLOOD PRESSURES ARE EQUALLY ASSOCIATED WITH CHANGES IN LEFT VENTRICULAR MASS: LONGITUDINAL ANALYSIS FROM THE UK BIOBANK COHORT STUDY

Background and objective.
Central blood pressure (BP) measurement purports to aid hypertension management. This concept is founded on cross-sectional studies, however, findings are mixed and none report longitudinal relationships between changes in BP and outcomes. This study aimed to determine associations of changes in cuff BP and central BP with changes in left ventricular mass index (LVMi), as an important hypertension-related clinical outcome.

Methods.
Standard cuff BP and central BP (Vicorder, Skidmore Medical, UK; SBP/DBP calibration of waveforms) were measured at the same time as cardiac magnetic resonance imaging for LVMi among a cohort of adults from the UK Biobank Cohort Study assessed at two time points (2014+ and 2019+). Linear regression adjusted for demographic and clinical characteristics were used to determine cross sectional associations and associations between changes in cuff BP and central BP with LVMi.

Results.
Data were evaluable for 681 participants (aged 50.1±7.1 years, 54% female) followed over 1161±582 days (mean ± SD). Cross-sectional analysis showed the association of cuff systolic BP with LVMi (β±SE 3.47x10-2±6.38x10-3 g/m2.7/mmHg) and central systolic BP with LVMi (β±SE=3.52x10-2±6.40x10-3 g/m2.7/mmHg) were comparable (p<0.001 both). In the longitudinal analysis, associations between the changes in BP and changes in LVMi were identical for both central and cuff systolic BP (β±SE=0.011±0.003 g/m2.7/mmHg; p<0.001 both).

Conclusion.
Changes over time in standard cuff BP provides similar information to central BP on risk for hypertension-related changes in LVMi. These findings are likely to be generalisable to central BP devices using SBP/DBP calibration.