Simple test for checking your heart health
With this new test we all can now easily how our heart is doing. Has your doctor ever checked your blood pressure in both arms? If not, you’re missing out on a valuable test of heart health. That’s the conclusion of Harvard instructor Ido Weinberg, MD, whose recent research shows that a more than 10-point difference in systolic blood pressure between arms can be a red flag for heart attack, stroke, and cardiovascular disease.
You’d expect that it wouldn’t matter which arm the nurse puts the cuff on – blood pressure is blood pressure, right? Not so fast. According to Weinberg’s study, published in the March issue of the American Journal of Medicine, about 10 percent of adults over 40 had interarm differences of more than 10 points – and this point spread was associated with an almost 40 percent increase in risk of heart attack, stroke, or other cardiovascular event.
While experts knew that very large differences in arm-to-arm blood pressure readings could suggest cardiovascular disease, this is the first research to link a relatively small difference of just 10 points with significantly increased risk. As part of Harvard/Massachusetts General Hospital’s Framingham Heart Study, the researchers followed 3390 healthy people age 40 and older (with no prior sign of heart disease), over a period of 13 years and found a 38% risk increase in those with a 10-point or greater arm-to-arm difference. (The average arm-to-arm or interarm difference, the researchers say, is less than 5 points.)
A previous study published in The Lancet in 2012 found that a 15-point arm-to-arm difference in systolic blood pressure doubled the risk of peripheral artery disease, or clogging of the arteries further away from the heart. Why is having a difference in blood pressure one one side of the body so significant? Because it suggests blockage or slowing of blood flow, most likely from artery-clogging plaque. The other potential cause, an aortic dissection or tear in the aorta, is even more serious. Concludes Weinberg: “This study supports the potential value of identifying the interarm systolic blood pressure difference as a simple clinical indicator of increased cardiovascular risk.”
Systolic blood pressure (the top number when your doctor tells you your BP is “X over X”) measures the pressure in your arteries as your blood flows through while your heart is beating. Diastolic, the second or lower number, measures blood pressure while the heart is resting between beats. You want your blood pressure under 120/80; above that is considered prehypertension and anything above 140/90 indicates hypertension and the need for intervention. According to the American Heart Association, systolic blood pressure is considered more important than diastolic as a measure of cardiovascular health because it shows how strongly and clearly your blood if flowing. If you’re like me, reading this study will make you want to run out and check your own arm-to-arm blood pressure ratio. If you have a home blood pressure monitor - a useful health tool for anyone whose BP is even slightly elevated – you can check both arms yourself right now. If not, you can get your blood pressure checked anytime at your local drug store, or ask the medical staff to repeat your blood pressure screening in both arms next time you see your doctor. Since 2005, the American Heart Association’s blood pressure screening guidelines have recommended taking blood pressure readings in both arms as a baseline reading. But I don’t know about you – I’ve never experienced that happening. So I’m certainly going to ask.
