[PP.16.06] INTER-ARM BLOOD PRESSURE DIFFERENCE IN AN UNSELECTED HYPERTENSIVE POPULATION

Objective: Accurately measuring blood pressure in the office is many times challenging since a multitude of methodological issues have to be taken into account in the clinical setting where sequential measurement of blood pressure between arms, digit bias from physicians and rushing the required interval between measurements have produced in many cases faulty measurements. By using an automated machine with an integrated BP measuring protocol in the office we aimed to investigate the real prevalence of interarm difference (IAD) and investigate differences between hypertensive subjects with and without IAD. Design and method: We compared 82 consecutive patients of the hypertension outpatient clinic of a tertiary hospital (mean age = 59.7 ± 15.8 years, females n = 50). We used the Microlife Watch BP office afib which has a dual-cuff design for convenient, simultaneous measurements of IAD and an in-built protocol of waiting 1 minute before the measurements and also 1 min between measurements. This protocol cannot be violated by the physician. Anthropometric characteristics and patient history were recorded for all patients. We defined as clinically significant interarm difference of 10 mmHg. Results: The mean systolic blood pressure (SBP) IAD was 5.3 ± 4.9 and mean diastolic (DBP) IAD was 3.1 ± 2.5 mmHg. Fourteen patients (17.1%) had a clinically significant IAD of >10 mmHg. Interarm difference for pulse pressure (PP) was 5.5 ± 4.7 mmHg. Fourteen patients (17.1%) had PP difference >10 mmHg. There was no difference in the percentage of patients that higher BP in the left hand (53.7%) and on the right (46.3%) (chi square = 0.44, p = 0.5). Conclusions: Methodological issues hinder reliable BP measurements. Proper BP measurement produced a substantial number of patients with significant interarm difference. Differences in PP between arms should be investigated in terms of their clinical significance. Left and right arms showed similar percentages in dominance in regards to SBP.