Faster Resting Heart Risky Even for the Fit

Even fit men with higher resting heart rates may have a higher risk of early death, a new study finds. The study included nearly 2,800 men who were middle-aged when they joined a health study in 1970. Researchers kept track of them for 16 years. The new study focused on resting heart rate. That's how fast your heart beats when you are relaxed and sitting still. Men whose resting heart rate was at least 80 beats per minute died earlier, on average, than men with a heart rate of 65 beats per minute. This was true even for men who exercised regularly. Researchers also adjusted the numbers to account for age, health habits and other factors. A higher heart rate was still linked with earlier death. The risk of death increased 16% for each 10 beats per minute in the resting heart rate. The journal Heart published the study online. HealthDay News wrote about it April 16.

By Howard LeWine, M.D.
Harvard Medical School

What Is the Doctor's Reaction?

Most visits to the doctor include a check of your heart rate. It's such a simple measurement. The nurse or doctor feels your pulse near the wrist, counts the beats for 15 seconds and multiplies the number by 4. That measures the number of beats per minute.

Today in most doctors' offices, heart rate measurement has become even easier. It's now usually done electronically with a blood pressure machine or with a sensor clipped at the end of your finger.

Your heart rate changes from minute to minute. It depends on whether you are standing up or lying down, moving around or sitting still, stressed or relaxed. When you have been at rest for a bit, the heartbeat settles down to a stable clip. This is your resting heart rate.

Traditionally, doctors have been taught that a normal resting heart rate is 60 to 100 beats per minute. Ideally, before a reading in the doctor's exam room, you have had time to sit for a while and relax (as relaxed as you can be in a doctor's exam room). If your heart rate is higher than 100 or lower than 60, your doctor will take notice and may want an EKG. Anything in between doesn't get much attention. But maybe it should.

During the last few years, experts have begun to recognize that faster resting heart rates are linked to the development of heart disease and shorter lives. The leading theory has been that resting heart rates in the 60 to 70 range most often reflect better fitness. And with better fitness you are less likely to develop heart problems and more likely to live longer.

This study found that people with higher resting heart rates (80 beats per minute or higher) had a shorter life expectancy than those with rates around 65 beats per minute. Previous studies have had similar findings. But what's new is that in this study higher resting heart rates meant shorter life expectancy even in fit people.

So what else causes a higher resting heart rate besides not being fit? Genes play a role. Aging tends to speed up the heart rate. People who smoke or drink too much alcohol generally have higher resting heart rates. Stress, medicines and medical conditions also influence the heart rate. These are all important factors that can shorten life expectancy.

What Changes Can I Make Now?

You don't need to go to your doctor to check your heart rate. It's easy to do at home the same way the nurse or doctor does it in the office. And your reading at home, in a relaxed atmosphere, probably gives a more accurate picture of your heart health.

The best time to measure your resting heart rate is before you get out of bed. Find the pulse in your wrist or neck, count the number of beats in 15 seconds, and multiply by four.

If your heart rate is greater than 100 and you have any symptoms, give your doctor a call. Such symptoms might be fatigue, lightheadedness, shortness of breath and/or chest pain.

A heart rate under 60 is common and could be a sign of being very fit. For example, when the tennis star Bjorn Borg was in his prime, his resting heart rate was 35! Many medicines also lower heart rate, especially beta blockers and other heart and blood pressure drugs. But again, if you are not extremely fit and are having any symptoms plus a very low heart rate, contact your doctor.

If you are otherwise healthy but have a resting heart rate of 80 beats per minute or higher, discuss this with your doctor at your next visit. You and your doctor can review any factors that may increase your risk of heart disease. It's always good to look at ways to reduce your risk of the No. 1 killer in the United States.

But you don't need to wait for your doctor's appointment. You can start to lower your heart rate today. Here's what you can do:

• Exercise more. When you take a brisk walk, swim or bicycle, your heart beats faster during the activity and for a short time afterward. But exercising every day gradually slows the resting heart rate.
• Reduce stress. The relaxation response, meditation, tai chi and other stress-busting techniques can lower heart rate over time.

What Can I Expect Looking to the Future?

Along with body weight and waist size, your resting heart rate is another way you can easily assess your health at home. How important to your health is lowering your heart rate? We don't know the answer to that yet. But you can expect more studies on this important question in the future.