Get the most out of home blood pressure monitoring

Checking blood pressure at home is an important part of managing high blood pressure (hypertension).

The American Heart Association (AHA) and other organizations recommend that people with high blood pressure monitor their blood pressure at home. Regularly checking blood pressure at home helps your care providers determine if treatment is working.

Home blood pressure monitors are available widely and without a prescription. But it's important to know how to find a good home blood pressure monitor and to use it correctly.

Why do I need to monitor my blood pressure at home?

Monitoring your blood pressure at home can:

• Help with early diagnosis. Self-monitoring can help your health care provider diagnose high blood pressure earlier than if you have only occasional blood pressure readings in a medical office. Home monitoring is especially important for people with elevated blood pressure or another condition that could contribute to high blood pressure, such as diabetes or kidney problems.
• Help track your treatment. The only way to know whether your lifestyle changes or medications are working is to check your blood pressure regularly. Monitoring blood pressure changes at home can help you and your care provider make decisions about treatment, such as adjusting dosages or changing medications.
• Encourage better control. Self-monitoring can give you a stronger sense of control over your health. Self-monitoring might help you feel more motivated to control your blood pressure with improved diet, physical activity and proper medication use.
• Cut your health care costs. Self-monitoring might help cut down on medical visits.
• Check if your blood pressure differs outside a medical office. Some people have spikes in blood pressure due to nervousness during a medical visit (white coat hypertension). Other people whose blood pressure is OK at a clinic have higher blood pressure elsewhere (masked hypertension). Monitoring blood pressure at home can help determine if you have true high blood pressure.

Not everyone can track blood pressure at home. For those with irregular heartbeats, home blood pressure monitors might not give an accurate reading.

Types of home monitors

Most pharmacies, medical supply stores and some websites sell home blood pressure monitors. Experts recommend an automatic or electronic device. Your health care provider can help you pick the monitor that's best for you.

Blood pressure monitors generally have the same basic parts:

• Inflatable cuff. The cuff's inner layer fills with air and squeezes the arm. The cuff's outer layer has a fastener to hold the cuff in place. The device calculates heart rate and blood flow by measuring the changes in the motion of the artery as the blood flows through while the cuff deflates.
• Gauge for readouts. Some blood pressure monitors can take several readings and report the averages.

Digital monitors that are fitted on the upper arm are generally the most accurate.

Some people with very large arms may not have access to a well-fitting upper arm cuff at home. If so, measuring blood pressure at the wrist or lower arm may be OK if used as directed and checked against measurements taken in your provider's office. For the most reliable blood pressure measurement, the American Heart Association recommends using a monitor with a cuff that goes around your upper arm, when available.

For people who can't check blood pressure at home, many pharmacies and stores have public blood pressure devices. The accuracy of these devices may vary.

Features to consider

When choosing a blood pressure monitor, consider:

• Cuff size. Having a properly fitting cuff is important. Cuffs that fit poorly won't give accurate blood pressure measurements. Ask your health care provider what cuff size you need.
• Display. The display that shows blood pressure measurements should be clear and easy to read.
• Cost. Prices vary. Ask your health insurance provider if your policy covers the cost of a home blood pressure monitor.

Device accuracy

Once a year, check the accuracy of your monitor by bringing it to your provider's office and comparing your monitor's readings with those taken at the office.

Tips for accurate use

No matter what type of home blood pressure monitor you choose, proper use requires training and practice. Take the device to your health care provider to make sure the one you've chosen is the best fit for you. Learn to use the monitor correctly.

To help ensure accurate blood pressure monitoring at home:

• Check to be sure your device is correct. Before using a monitor, have your health care provider compare the readings from your monitor with the readings from the monitor in the medical office. Also have your provider watch you use the device to see if you're doing it properly. If you drop the device or damage it, have it checked before using it again.
• At the beginning, measure your blood pressure at least twice daily. Take it first in the morning before eating or taking any medications. Take it again in the evening. Each time you measure, take two or three readings to make sure your results are the same. Your health care provider might recommend taking your blood pressure at the same times each day.
• Don't measure your blood pressure right after you wake up. You can prepare for the day, but don't eat breakfast or take medications before measuring your blood pressure. If you exercise after waking, take your blood pressure before exercising.
• Avoid food, caffeine, tobacco and alcohol for 30 minutes before taking a reading. Also, empty your bladder first. A full bladder can increase blood pressure slightly.
• Sit quietly before and during monitoring. When you're ready to take your blood pressure, sit for five minutes in a comfortable position with your legs and ankles uncrossed. Your back should be supported against a chair. Try to be calm and not think about stressful things. Don't talk while taking your blood pressure.
• Make sure your arm is positioned properly. Always use the same arm when taking your blood pressure. Rest your arm, raised to the level of your heart, on a table, desk or chair arm. You might need to place a pillow or cushion under your arm to raise it high enough.
• Place the cuff on bare skin, not over clothing. A rolled-up sleeve that's tight around your arm can affect the reading. You may need to slip your arm out of the sleeve.
• Take a repeat reading. Wait 1 to 3 minutes after the first reading, and then take another. If your monitor doesn't keep track of blood pressure readings or heart rates, write them down.

Blood pressure varies throughout the day. Readings are often a little higher in the morning. Also, your blood pressure might be slightly lower at home than in a medical office.

Contact your health care provider if you have any unusual increases in your blood pressure or if your blood pressure stays higher than usual. Ask your provider at what reading you should call the medical office right away.

Tracking your blood pressure readings

Some people use a notebook to record their blood pressure readings.

If you have an electronic personal health record, you might choose to record your information using a computer or mobile device. This gives you the option of sharing your readings with your health care providers and family members. Some blood pressure monitors upload this data automatically.

Long-term benefits

If your blood pressure is well controlled, ask your health care provider how often you need to check it. You might be able to check it only once a day or less often. If you're just starting home monitoring or changing treatment, your provider might recommend checking blood pressure starting two weeks after treatment changes and a week before your next appointment.

Home blood pressure monitoring is not a substitute for medical visits. Home blood pressure monitors might not always be correct. Even if you get readings that are typical for you, don't stop or change your medications or your diet without talking to your care provider first. However, if continued home monitoring shows your blood pressure is under control, you might be able to make fewer medical visits.