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Is Your Blood Pressure Accurate?
Studying for a blood pressure test may actually help you ensure more accurate readings—and possibly save you money on medication and insurance.
“Think of having your blood pressure taken as a science experiment,” says Daniel Sullivan, M.D., an internist at the Cleveland Clinic. For the result to be valid, you need to use the same criteria each time, he says. If not, the results could vary—sometimes wildly. For instance, blood pressure readings may be different in the morning than they are at the end of the day. If you take cold medicine before your blood pressure is checked, the results might indicate a problem. Even shifting your posture can alter your results.
“Blood pressure is one of many criteria used to determine premiums, along with gender, height, age, weight, and whether you smoke,” says Alison Moy, M.D., medical director, Liberty Life Assurance Company of Boston, a member of Liberty Mutual Group. “In terms of blood pressure ranges, we follow clinical definitions of hypertensive and pre-hypertensive to determine rates.”
While each insurance company uses its own criteria to decide rates, higher blood pressure means higher prices. Those rates could be based on a misreading.
For accurate readings, Sullivan suggests keeping this checklist in mind when having your blood pressure checked.
•Pull up a chair. A common mistake is having your blood pressure taken while you sit on an exam table with your legs dangling. This could raise blood pressure by 10 points. Instead, sit in a chair.
•Sit up straight. Don’t slouch. Your back should rest against the chair back.
•Keep your feet on the floor with your legs apart and relaxed. Don’t cross your legs at either the knees or ankles.
•Check arm positioning. Allow the person taking your pressure to support your arm. The arm cuff should be at the same level as your heart.
Time and place
•Schedule your readings for the afternoon. Blood pressure tends to be higher in the morning.
•Take it at home, too. In a doctor’s office, you may feel anxious, which can elevate blood pressure. Several inexpensive monitors allow you to check your pressure at home, where you’re more relaxed.
•Make sure the cuff is sized correctly. If the cuff is too small, it can make your pressure look elevated, causing a difference of up to 15 points in the reading. If the Velcro starts to pop off, the cuff may be too small.
•Confirm zero calibration. Before your blood pressure is taken, ask if the monitor has been calibrated to zero, a procedure often neglected.