University of Michigan 412 Maynard St. Ann Arbor, MI 48109-1399 December 1, 1998 (2)
Contact: Amy Reyes Phone: (734) 647-4411, [email protected]
Protect your aging heart: U-M researcher addresses changes in the heart as it ages.
ANN ARBOR---To stave off heart disease, one should understand how the heart changes as it ages, because heart disease doesn't occur suddenly. It's a progression that occurs over time and is influenced by gradual changes that weaken the heart.
These changes begin early in life with arterial stiffening in the teen years. By age 20, your maximum heart rate begins to slow by one beat a year and by age 30, you begin to produce less of a protein that regulates how long each beat lasts, which means your heart must work harder on each beat to keep up its normal output.
"Aging itself is not a disease and it is not unhealthy to age, but it does place some limitations on the heart. Those limitations cannot be reversed, but they can be attenuated. You can't make an old heart look like a young heart, but you can make an old heart look younger," said Marvin O. Boluyt, assistant research scientist with the University of Michigan Division of Kinesiology. Boluyt is co-author of "Cardiovascular Aging in Health," a chapter in the newly published book "Advances in Organ Biology," edited by E. Edward Bittar.
Published by JAI Press of Stamford, Conn., "Advances in Organ Biology" is a collection of chapters by scientists specializing in heart failure. The book focuses on new advances that have been made in defining one aspect of heart disease: the changing metabolism.
Boluyt and co-author Dr. Edward G. Lakatta, chief of the Laboratory of Cardiovascular Science at the Gerontology Research Center in Baltimore, examine the normal changes the heart goes through in the aging process. The changes---such as reduced protein levels that slow the heartbeat---aren't threatening by themselves.
However, coupled with a history of illness and a sedentary lifestyle, these changes in the heart could throw a healthy, but stressed, heart into turmoil.
There are primarily two ways your heart changes with age: everyday wear and tear (such as by disease and hormonal changes), and changes that occur naturally (such as the change in protein that regulates the heart beat).
Lifestyle changes and medication are the most effective means in prevention of heart disease, while gene therapy is beginning to show promise for some types of heart disease, Boluyt said.
"Exercise and a healthy lifestyle don't prevent all of the age-related changes, but they do reverse or prevent some of the changes that occur, such as reversing the decrease of a key protein level (exercise can boost the levels of a key protein called SR calcium ATPase). That's been shown very clearly in studies done on rats," he said.
Increased levels of SR calcium ATPase can increase the reserve capacity of the heart, which decreases with age. The larger the reserve capacity of the heart, the better it is at dealing with a sudden insult. Thus, exercise not only reduces the chances of having a heart attack, it also can increase the chances of surviving a heart attack, Boluyt said.
"Regular exercise can delay or partially reverse some of these changes in the heart and improve the reserve capacity while reducing the risk of heart disease. Exercise can keep you and your heart younger. It won't ever be as young as it once was, but it'll keep you healthier," he said.
Heart disease is a mix of many diseases that take a toll on the heart as it ages, but especially after age 60 when the chances of developing heart disease and heart failure steadily rise. Even without a history of heart disease or high blood pressure, the chances of developing heart disease later in life increase with age.
"Even if you take away all of the diseases, the heart still changes with age. Those changes are not necessarily bad. Those changes by themselves would not impair the heart, but they reduce the reserve capacity of the heart so that it is less able to deal with a heart attack," Boluyt said.
# # # # # #
RSS