Association between four-limb blood pressure differences and arterial stiffness: a cross-sectional study

Objectives Although inter-arm blood pressure difference (IAD) and inter-ankle blood pressure difference (IAND) have been shown to be associated with cardiovascular disease, controversy remains. In this study, we investigated the prevalence of IAD and IAND as well as the correlation with arterial stiffness and systolic blood pressure in a large number of the Chinese population. Methods The four-limb blood pressure, IAD, IAND, brachial-ankle pulse wave velocity (baPWV) and ankle-brachial index (ABI) of 12,176 participants have been measured. Multivariate logistic regression analysis was used to analyze the relationship of the increase in IAD/IAND with arterial stiffness and blood pressure. Reporting adheres to the STROBE guidelines. Results In 12,176 participants, 1832 (15%) subjects had an IAD >= 10 mmHg, 663 (5%) had an IAD >= 15 mmHg, and 291 (2%) had an IAD >= 20 mmHg. Correspondingly, 4548 (37%) had an IAND >= 10 mmHg, 2706 (22%) had an IAND >= 15 mmHg, and 1706 (14%) had an IAND >= 20 mmHg. baPWV was significantly higher in those with an IAD >= 10 mmHg (1881 +/- 487 cm/s vs. 1943 +/- 508 cm/s, P = 0.036) and IAND >= 10 mmHg (1850 +/- 476 cm/s vs. 1955 +/- 509 cm/s, P = 0.000). Compared to others, those with IAD or IAND >= 10 mmHg had higher systolic blood pressure (SBP), higher prevalence of hypertension, larger male gender ratio, bigger body mass index, higher pulse rate and lower ABI (P < 0.001 for all). A significant association with baPWV was observed for IAND >= 10 mmHg (OR = 1.117; 95%CI: 1.039-1.201; P = 0.003) not for IAD >= 10 mmHg (OR = 0.771; 95%CI: 0.699-0.851; P = 0.000) in multivariate logistic regression analysis. Conclusions Limb blood pressure differences were closely related to arterial stiffness and systolic blood pressure, allowing for a more comprehensive assessment of cardiovascular risk.