Inter-arm blood pressure difference and mortality: a cohort study in an asymptomatic primary care population at elevated cardiovascular risk

Abstract

ConclusionSystolic IADs in blood pressure are associated with increased risk of cardiovascular events, including mortality, in a large cohort of people free of pre-existing vascular disease.

Interarm blood pressure difference: Magnitude and prevalence in healthy adults

“…[8] However, a meta-analysis on the prevalence of IAD has shown a very variable proportion of subjects (1.4-38%) with IAD more than 10 mmHg. [7,[23][24][25][26][27] Various pathological causes have been considered as leading to an increase in interarm BP differences such as atherosclerosis, vasculitis, fibromuscular hyperplasia, connective tissue, and thoracic outlet compression. [10][11][12][13][14][15] In the absence of anatomic obstruction, interarm differences in SBP were thought to be related to some intrinsic property of the cardiovascular system.…”

Blood pressure measurement: a call to arms

“…6 Handedness neither predicts nor determines IAD but atrial fibrillation can impede assessment. 2 A confirmed, significant IAD in blood pressure could be stored prominently on the electronic health record using, for instance, the Read code 'Unequal blood pressure in arms' (246k) both to inform clinical management and to enable later searches, audit, and research.…”

“…Even IADs of <10 mmHg, which are, unsurprisingly, even more common, could impair follow-up of lifestyle and medication changes, which individually have an impact on blood pressure in the range of 3-15 mmHg. 2 Some groups of patients should be excluded from the routine measurement of IAD. These include patients with dialysis fistulae who are specifically advised to stop anyone taking a BP in the affected arm.…”

“…1,2 Interestingly, the work of Sheppard and colleagues suggests that variation across consecutive blood pressure measurements during a single clinic visit is neither random nor meaningless. They show that a large decrease in blood pressure across multiple readings is predictive of the white-coat effect (lower out-of-office pressure), whereas an increase in pressure is likely to indicate the converse, so-called masked hypertension (higher out-of-office pressure).…”

“…A single sequential pair of measurements can rule out an IAD of ≥10 mmHg with a high negative predictive value but yields high prevalences of IADs, with potential confounding by BP variability. 1,2 Therefore, an apparent IAD should be confirmed by repeated sequential measures or, better still, by repeated simultaneous measures.…”