The interarm blood pressure difference as predictor of cardiovascular events in patients with hypertension in primary care: cohort study

Abstract

Objectives of this study were to measure the prevalence of a difference in blood pressure (BP) between arms and determine whether a difference is associated with increased risk of cardiovascular events or death. A prospective cohort study of 247 patients with hypertension was undertaken in one rural general practice in England. The main outcome measures were mean difference in BP between arms and new episodes of myocardial infarction, cerebrovascular event, onset of angina or peripheral vascular disease or death. A total of 57/247 (23%) patients had a mean difference in systolic BP between arms of X10 mm Hg and 8/247 (3%) had a mean difference of X20 mm Hg. A total of 15/247 (6%) patients had a mean difference in diastolic BP between arms of X10 mm Hg. Survival analysis after 4.7 years (range 3.3-5.9) showed a shorter mean survival time without event or death for patients with a difference in systolic BP of X10 mm Hg compared with a difference of o10 mm Hg (3.7 (95% confidence interval, 3.2-4.2) versus 4.8 (4.6-5.1) years; Po0.001; hazard ratio 2.5 (1.5-4.2), P ¼ 0.001). Difference in systolic BP of X10 mm Hg between arms is common in this primary care population and is associated with a shorter survival time to death or new cardiovascular event. Detection of a difference between arms may identify hypertensive patients at increased risk of cardiovascular events. Such an approach would allow more effective targeting of resources in primary prevention strategies.

Association of Inter-arm Blood Pressure Difference with Atherosclerosis in Patients without Cardiovascular Diseases

“…But there were no reports about the quantitative correlation between the differences of simultaneously measured IABP and ABI or baPWV. In contrast with our results, some studies 2,15,19) showed that low ABI, ABI less than 0.9, or high baPWV was correlated with inter-arm SBP difference.…”

Difference in Blood Pressure between Arms of Normotensive Female Farmers in the Semi-arid Midlands of Kenya

“…Other studies have reported a prevalence of inter-arm differences in BP ranging from 12.0 to 18.4% for a systolic difference (sIAD) X20 mmHg and from 13.0 to 33.7% for a diastolic difference (dIAD) X10 mm Hg in various populations (8). In contrast, the systolic and diastolic BP differences were -1.18 mmHg and 0.72 mmHg for SBP and DBP, respectively in this rural Kenyan community population.…”

“…It was first recognised more than 100 years ago [8]. Hence, 13 out of 15 blood pressure guidelines recommend that BP should be measured on both arms during initial clinical evaluation [16,17] and the arm with the higher BP be used at subsequent visits, but there is little evidence that this is followed [18].…”

“…For more than 25 years, hypertension guidelines have recommended measuring BP in both arms, but acceptance among general practitioners is low [5]. Appreciation of the presence of an Inter Arm Differences (IAD) clearly is vital for the accurate diagnosis and consistent management of hypertension [8]. Suffice to say that the relationship between inter-arm systolic blood pressure difference and risk of future cardiovascular disease is uncertain [14].…”

“…Measurement of BP is the investigation most frequently undertaken in primary care settings and patients often have different BP measurements in their arms [8]. The presence of a difference between arm measurements has been implicated in a delayed diagnosis of hypertension.…”