Is Cardiorespiratory Fitness Level Linked to Heart Failure and Heart Attack Hospitalization?

Cardiovascular disease includes all diseases affecting the heart and blood vessels, and has been the leading cause of death for U.S. men and women for the past century.

Two major types of cardiovascular disease are heart failure and coronary heart disease. Heart failure is a condition that is typically characterized by a gradual decline in the heart’s ability to pump and fill properly. Heart failure is the leading cause of hospitalization in the U.S. for individuals ages 65 and older, and accounts for approximately 10% of all cardiovascular disease deaths. There are currently just over 6 million Americans who are living with heart failure. Coronary heart disease is a condition where one or more arteries within the heart is significantly blocked with fatty plaque. Rupture of this plaque often causes blood clot formation at the site of rupture, which then leads to heart attack. There are approximately 800,000 heart attacks annually in the U.S., with approximately 15% resulting in death.  

Several studies have shown convincingly that higher levels of cardiorespiratory fitness (CRF) are associated with decreased risk of death from cardiovascular disease. However, less is known regarding CRF and non-fatal cardiovascular disease events. To this end, researchers from The University of Texas Southwestern Medical Center and The Cooper Institute combined to publish a study in Circulation: Heart Failure. A total of 20,642 healthy men and women with an average age of 49 years underwent a comprehensive baseline exam at The Cooper Clinic between 1970 and 2009. The exam included included a maximal treadmill exercise test to measure CRF. Participants were placed in categories of low, moderate, or high CRF based on their age, sex, and treadmill test performance. During the  follow-up period which utilized Medicare data, there were 1,051 hospitalizations for heart failure and 832 hospitalizations for heart attack. In Figure 1 below, the risk for heart failure hospitalization across fitness levels is shown for men and women separately.

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In Figure 1 above, we see that compared to low fit men, those who were moderately or highly fit were 40% and 69% less likely, respectively, to be hospitalized for heart failure. For moderately or high fit women, the corresponding numbers were 47% and 62%, respectively.

In Figure 2 below, the risk for heart attack hospitalization across fitness levels is shown for men and women separately.

In Figure 2 above, we see that compared to low fit men, those who were moderately or highly fit were 26% and 44% less likely, respectively, to be hospitalized for heart attack. For moderately or high fit women, the corresponding numbers were 27% and 38%, respectively.

To our knowledge, this was the first study to examine the association of cardiorespiratory fitness with heart failure and heart attack hospitalization.

Compared to those who were low fit, men and women with moderate or high levels of fitness were significantly less likely to be hospitalized with heart failure or heart attack during the follow-up period. It is important to note that several factors that might have ‘muddied the waters’ were taken into account during the data analysis phase of the study. These factors included age, smoking, body mass index, resting blood pressure, blood cholesterol level, and length of follow-up.

Benjamin Franklin is credited with the saying “An ounce of prevention is worth a pound of cure.” Here is what you can do to reduce your risk of developing and/or dying prematurely from heart failure and coronary heart disease.

• Get a thorough annual physical exam after the age of 40 and follow the recommendations from your primary health care provider.
• Obtain a measurement or an estimate of your cardiorespiratory fitness level.
• Monitor and control your blood pressure if you have hypertension.
• Monitor and control your blood glucose level if you have prediabetes or diabetes.
• Monitor and control your blood cholesterol and blood triglyceride levels.
• Avoid obesity. Lose weight if you are overweight.
• Avoid tobacco in all forms.
• Avoid excessive alcohol intake. Completely avoid alcohol if you have a health condition that is made worse by alcohol
• Avoid sedentary lifestyle. Strive to attain at least a moderate level of cardiorespiratory fitness compared to others of your same age and sex.
• If you have sleep apnea, use a CPAP or APAP machine every night.
• Consume a heart-healthy diet such as the DASH or Mediterranean Diet.
• Learn the signs and symptoms of heart failure and heart attack by visiting www.heart.org

Reference

Berry, J., et al. (2013). Physical fitness and risk for heart failure and coronary artery disease. Circulation: Heart Failure. 6(4):627-634.

American Heart Association (www.heart.org)

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