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.

Delirium-predisposing factors are closely associated with changes in the temporal profile of serum anticholinergic activity and thus neutralize the previously documented association between higher SAA levels and delirium. An independent relationship of SAA to delirium presence is highly questionable.