Your doctor may have asked you to measure your blood pressure at home. Measuring your blood pressure helps you and your doctor determine if treatments or medications are working. Frequent testing can also help keep blood pressure under better control. Here are some tips to make sure your at-home readings are as accurate as possible.

Create A Routine

Try to test your blood pressure at the same time every day. For example, 3 hours after you’ve gotten up, 1 - 2 hours after your morning blood pressure medications, and 2 hours after your cup of coffee. Factors like time of day, caffeine level, stress, physical activity, and how long it’s been since you took your medications can all change the number on the cuff. Creating a routine reduces the chance of variation from those factors.

Follow Best Practices

Along with your routine, be sure to follow these best practices for getting a good reading:

1. Avoid smoking, exercising, or drinking caffeinated or alcoholic beverages for at least 30 minutes before measuring.

2. Sit down and relax for at least 5 minutes before testing.

3. Sit still in a chair with your feet flat on the floor and your back straight and supported. Rest your arm on a flat surface at heart level.

4. Use the cuff properly. Place the bottom of the cuff above the bend of your elbow, and be sure to have the cuff oriented the right way. For example, some cuffs have a small symbol that should be placed on the inside of your arm, with the tube pointing down. Each cuff will have specific guidelines on where and how to place the cuff properly. Here’s detailed guidelines for the Withings BPM Connect and the BodyTrace Cuff.

5. Take at least 2 readings 1 minute apart at the times specified in your plan. For example, 2 readings before morning meds, and 2 readings before dinner. If you have a Bluetooth enabled blood pressure cuff, connect it to Brook so your readings are automatically logged. See instructions for connecting devices to Brook here.

Variation is Normal

You may notice that the blood pressure reading at the doctor is often very different from the one you get at home. There’s a number of factors at play here, including how the blood pressure machine works. If it’s much higher at the office, you may be experiencing something called “white coat syndrome,” which just means you’re a little more nervous in the clinic than you are at home. Feeling nervous or stressed can increase blood pressure.

Most at-home blood pressure cuffs, like the Withings BPM Connect and the BodyTrace BP Cuff, are clinically tested for validity. All health data measuring devices have an allowable margin of error, but are tested to make sure the margin is small enough to pass medical device clearance.

Reasons Blood Pressure Fluctuates

There are many reasons why a blood pressure reading changes. First and foremost, blood pressure varies quite a lot during our day. It’s not like our weight that stays relatively the same all day - your blood pressure is constantly adjusting to match your needs. For example, your blood pressure when you are relaxed and laying down is going to be very different than if you jumped out of bed and climbed a flight of stairs. Even though those two moments might have been 30 seconds apart, your blood pressure will be very different. 

All the factors mentioned in this article affect blood pressure, and therefore blood pressure readings. That’s why it’s so important to be consistent with the environment you test in. 

If you get a reading that seems too high or low, check to make sure you are using the “best practices” listed above, relax for 5 minutes, and test again.

If your blood pressure remains much higher or lower than usual after checking multiple times, please contact your doctor.