Simultaneous Compared With Sequential Blood Pressure Measurement Results in Smaller Inter‐Arm Blood Pressure Differences

Abstract

There are currently few recommendations on how to assess inter-arm blood pressure (BP) differences. The authors compared simultaneous with sequential measurement on mean BP, inter-arm BP differences, and within-visit reproducibility in 240 patients stratified according to age (<50 or ≥60 years) and BP (<140/90 mm Hg or ≥140/90 mm Hg). Three simultaneous and three sequential BP measurements were taken in each patient. Starting measurement type and starting arm for sequential measurements were randomized. Mean BP and inter-arm BP differences of the first pair and reproducibility of inter-arm BP differences of the first and second pair were compared between both methods. Mean systolic BP was 1.3AE7.5 mm Hg lower during sequential compared with simultaneous measurement (P<.01). However, the first sequential measurement was on average higher than the second, suggesting an order effect. Absolute systolic inter-arm BP differences were smaller on simultaneous (6.2AE6.7/3.3AE3.5 mm Hg) compared with sequential BP measurement (7.8AE7.3/4.6AE5.6 mm Hg, P<.01 for both). Within-visit reproducibility was identical (both r=0.60). Simultaneous measurement of BP at both arms reduces order effects and results in smaller inter-arm BP differences, thereby potentially reducing unnecessary referral and diagnostic procedures. J Clin Hypertens (Greenwich). 2013;15:839-844. ª2013 Wiley Periodicals, Inc.Inter-arm blood pressure (BP) differences have been established since the early 20s of the last century.1 The importance of assessing inter-arm BP differences is to prevent underestimation and undertreatment of hypertension because the arm with the highest BP should be taken as a reference. Therefore, guidelines on BP measurement recommend bilateral BP measurement at a patient's first visit.2,3 In addition, large inter-arm BP differences in systolic BP (SBP) may indicate the presence of atherosclerotic plaques and other vascular occlusive diseases and are associated with increased cardiovascular risk. 4,5 A recent meta-analysis of studies assessing the inter-arm BP differences showed that a SBP difference ≥15 mm Hg was associated with an increased risk of cardiovascular mortality.6 This is in line with another recent prospective study in hypertensive primary care patients, which showed that a BP difference of ≥10 mm Hg was an independent predictor of cardiovascular events and all-cause mortality after 10 years of follow-up.

Relationship between inter-arm blood pressure differences and future cardiovascular events in coronary artery disease

“…Consequently, in recent studies, IAD has been measured simultaneously with an automatic oscillometric device [30]; IADs in recent reports have differed widely from those cited in earlier reports. Therefore, it is preferable to measure blood pressure simultaneously in both arms to gain accurate IAD [19,20]. We therefore measured IAD simultaneously by using an ABI type of device in this study.…”

“…A recent study by Charmoy et al [6] showed that unilateral cuff inflation to measure blood pressure can increase the blood pressure values in the contralateral arm; thus, IADs ascertained by sequential measurement of bilateral brachial blood pressures may be greater than those obtained by simultaneous measurement of these blood pressures [19]. Because published meta-analyses employ different kinds of techniques (simultaneous technique or sequential technique) for measuring bilateral blood pressures [20,21], there are disproportionate rates of patients with IAD more than 10 mmHg in these metaanalyses.…”

Inter‐Arm Blood Pressure Differences May Be Important for Predicting Mortality

“…3 The impact of IAD during BP measurements has been a subject of extensive research in recent years. 4,5 There may be a relationship between IAD and increased risk of cardiovascular morbidity in older patients. 5 In the present study, the characteristics of vascular disease in the patients were not emphasized.…”

Association of simultaneously measured four-limb blood pressures with cardiovascular function: a cross-sectional study

“…Therefore, it is an important that four-limb blood pressure should be simultaneously measured to identify and manage the cardiovascular disease. However, most evidences on cardiovascular disease from these studies are obtained by either measuring single limb blood pressure or performing sequence measurement instead of simultaneous four limbs measurement [4–6]. Current technology has allowed to measure four-limb blood pressure simultaneously [7], which could generate accurate blood pressure differences between four limbs, provide a comprehensive evaluation of blood pressure and improve the accuracy of blood pressure for cardiovascular disease diagnosis [2, 4].…”