Prospective relationships between left ventricular mass, brachial and central blood pressures in participants from the UK Biobank.

Abstract

Background: Central SBP purports to aid hypertension management. This concept is founded on cross-sectional studies; however, findings are mixed and few report longitudinal relationships between changes in blood pressure (BP) and outcomes. This study aimed to determine associations of changes in brachial BP and central BP with changes in left ventricular mass index (LVMi), as an important hypertension-related clinical outcome.

Methods: Standard brachial BP and central BP (Vicorder, Skidmore Medical, UK; a type 1 device, using SBP/DBP calibration) were measured at the same time as cardiac MRI for LVMi among adults from the UK Biobank Cohort Study assessed prospectively at two time points (2014+ and 2019+). Analysis was by linear regression adjusted for demographic and clinical characteristics.

Results: Data were evaluable for 681 participants (aged 50.1 ± 7.1 years, 54% women) followed over 3.2 ± 1.6 years [mean ± standard deviation (SD)]. Cross-sectional analysis showed the association of brachial SBP with LVMi [β ± standard error (SE) 3.47 × 10-2 ± 6.39 × 10-3 g/m2.7/mmHg] and central SBP with LVMi (β ± SE = 3.52 × 10-2 ± 6.40 × 10-3 g/m2.7/mmHg) were comparable (P < 0.001 both). In longitudinal analysis, associations between the changes in BP and changes in LVMi were identical for both central and brachial SBP (β ± SE = 0.011 ± 0.003 g/m2.7/mmHg; P < 0.001 both). Findings were unchanged if participants were stratified by age, LVMi quartile, BP category or central BP phenotype.

Conclusion: Changes over time in standard brachial BP provide similar information to central BP on changes over time in LVMi. Whether these findings are generalizable must be further investigated in other cohorts and by other types of central BP devices.