The day may be rapidly approaching when your primary healthcare provider will take your blood pressure from both arms simultaneously. That's according to a meta-analysis in this week's Lancet, also featured in our YouTube, taking a look at a number of studies that examined the difference in blood pressure between arms and its predictive value. Turns out this low tech assessment method may provide an idea of whether blood vessels are either occluded or narrowed, putting someone at risk for a host of cardiovascular events. As Rick points out in this week's podcast, a significant difference in these measurements suggests additional follow-up is needed.
A total of 20 studies were included for analysis in this paper. Studies that included measurement of blood pressure in both arms and also stenosis or narrowing of the subclavian artery, (the major blood vessel to the arm), peripheral vascular disease, cerebrovascular disease, cardiovascular disease, or mortality were included. The analysis concluded that a difference of 15 mm Hg or more between arms was associated with the presence of vascular disease and all-cause mortality. Even a 10mm Hg difference seemed to indicate the presence of peripheral vascular disease.
The authors and Rick agree that simultaneous measurement in both arms is the best method for obtaining these blood pressures, and that the devices must be calibrated properly. Additionally, the patient must be seated for a minimum of five minutes previous to any attempt to obtain a blood pressure measurement, and of course, taking more than one measurement is advantageous. Rick opines that this is rarely possible in a typical clinic setting and may hinder adoption of the practice, but since it isn't technically difficult to train health care providers other than physicians to obtain blood pressure measurements, it doesn't seem that onerous to me.
What I like about this study is it demonstrates a very low tech, low risk technique for identifying folks who may be at increased risk for vascular disease, cardiovascular events, and death. Since it is a low tech method it can be done almost anywhere worldwide where two, ideally the same type, blood pressure measuring devices are available. So in a country with the resources, a difference of 15mm Hg or more should prompt further evaluation and identification of the specific risk, as well as immediate strategies to reduce that risk, whether via blood pressure reduction, improvement of the cholesterol profile, perhaps through the use of statin medications, and implementation of lifestyle modifications, including exercise and smoking cessation. Even in countries without the resources to follow up suspicion with more rigorous assessment, adoption of risk reduction strategies is likely to be of benefit.
Other studies this week include a look at re-excision among women who've already had surgery in early stage breast cancer, in JAMA, good news regarding survival for children who've been badly burned in the Lancet, and a stage 3 study of a potential new medication for uterine fibroids for NEJM. Until next week, y'all live well.