This comment, made nearly four centuries ago, raises a provocative modern-day question: Do you know how old your arteries are?
It is a question gaining increasing attention as researchers look for more effective ways to communicate risk of cardiovascular disease to patients and to motivate them to make changes in their lives that can help prevent heart attacks, strokes and other serious heart-related problems later in life.
Several tools are available that enable doctors and patients to calculate vascular age. These suggest there can be a substantial difference between how old you are and how old your blood vessels are. For instance, the vascular age of a 35-year-old man who smokes and has diabetes, high blood pressure and abnormal cholesterol could be as high as 76 years old—more than double his chronological age, according to a recent study. The arteries of a 30-year-old woman with similar risk factors could be equivalent to those of an average woman who is more than 80 years old.
Such a calculation "gives a sense that your risk-factor burden is making you age faster than you think you are," says Donald Lloyd-Jones, a preventive cardiologist at Northwestern University, Chicago, who co-authored the recent study, which appeared in the journal Circulation last August. "The more you can make it concrete, the better you can impart information about risk."
The good news, doctors say, is that by taking steps to reduce risk factors and the damage they inflict on arteries, it is possible to turn back the clock on vascular age.
Rejuvenating Your Arteries
People's vascular age can be different than their chronological age. But lifestyle changes and medication can help bring them in line.
- A 42-year-old man who smokes and has total cholesterol of 180, good cholesterol (HDL) of 45 and systolic blood pressure of 125, has a vascular age of a 54-year-old. If he quits smoking, his vascular age could drop to 42, the same as his chronological age.
- A 52-year-old nonsmoking woman, who has total cholesterol of 220, HDL of 44 and systolic blood pressure of 135, has a vascular age of a 68-year-old. If the woman reduces her cholesterol below 200, her vascular age could drop to 59 years old.
With optimal cholesterol and blood pressure and no diabetes, the vascular age of a 74-year-old non-smoking man could be as low as 60, according to the report by Dr. Lloyd-Jones. A similarly healthy 74-year-old woman could have arteries as young as 53, or 21 years less than her chronological age.
The concept of vascular age underscores the crucial role blood vessels play in maintaining heart health. A single layer of cells called the endothelium lines the walls of every blood vessel in the body. Along with a layer of elastic tissue, the endothelium comprises what is called the intima.
Bryan Donohue, chief of cardiology at University of Pittsburgh Medical Center Shadyside, calls the intima "the governing intelligence" of vascular health. Knowledge it contains and communicates with the blood enables blood to course through the body without clotting, he says. It also helps to keep arteries flexible or compliant.
Over time, however, the effects of high blood pressure, cholesterol, blood sugar and tobacco smoke provide a toxic milieu that injures the endothelium. That causes an inflammatory response intended to heal the artery wall, but that in the face of continuous injury only makes things worse.
The progressive result is an accumulation of fatty deposits called plaque that can rupture or have their caps shear off, causing clots that lead to heart attacks. In addition, artery walls can stiffen, transforming compliant arteries into conduits like "Styrofoam tubes," Dr. Donohue says, that increase both blood pressure and the workload on the heart.
All of this explains in part why heart experts are concerned that the nation's obesity epidemic and the surge in diabetes rates threaten to unravel decades of progress against heart disease. Both high body mass, particularly belly fat that accounts for a person's bulging waist line, and diabetes have a pernicious effect on the health of adult blood vessels. In addition, recent research among children and adolescents at Cincinnati Children's Hospital and elsewhere has documented arterial stiffness and other heart-related structural abnormalities once thought to occur only in aging adults.
Even if your weight is under control, high cholesterol, high blood pressure, smoking, sedentary living and stress all are culprits that can accelerate vascular age. Over time, the steady beating of your heart—70 times a minute, or more than 100,000 heartbeats a day—exacts wear and tear on your vessels as well.
Dr. Lloyd-Jones's analysis of vascular age is based on an updated version of the Framingham Risk Score, a widely used instrument that uses a formula based on gender, age, cholesterol and blood pressure levels and smoking status to estimate a person's 10-year risk of a heart attack or heart-related death. The new version, published in Circulation in 2008, added stroke, heart failure and disease in the leg arteries to broaden the scope of the tool, as well as a point system that linked a relative 10-year risk to vascular age.
"People may have a low 10-year risk, but their 40-year risk is going to be large," says Ralph D'Agostino, a Framingham Heart Study investigator and mathematician at Boston University. Looking at vascular age can "let them know where they might be heading if they don't start paying attention."
Similar warnings can come from deriving vascular age from a CT scan that detects accumulation of calcium in the coronary arteries, or on an ultrasound test known as CIMT (for carotid intima media thickness) that measures the thickness of the inner lining of the carotid arteries in the neck.
Typically, results of these tests are expressed in percentiles and risk probabilities, which "human beings don't understand at all," says Dr. Lloyd-Jones. For instance, a Framingham score may indicate someone has a 7% chance, or low risk, of having a heart attack in the next 10 years. "If I say you are 45, but you have the risk of an otherwise healthy 67-year-old,' that somehow gets in our brain better" than a percentage risk, he says.
Dr. Lloyd-Jones cautions that there isn't evidence linking a calculation of artery age directly to what's actually going on inside a patients' vessels. But, he says, "We hope this is another way to get patients to pay attention to their lifestyle and adhere to medicines if they need them." Peter Tripoli is a case in point. A few weeks ago, the 50-year-old vice president of a software firm experienced shortness of breath and chest pain. Several tests didn't find any evidence of obstruction, but he went to Dr. Donohue's clinic in Washington, Pa., for a checkup with Linda Gordon, a nurse practitioner.
Mr. Tripoli, thick around the waist, acknowledged he had gained 40 pounds in the past three years. During the same time, his total cholesterol jumped to 249 from 192.
Mrs. Gordon took his blood pressure, which was 98/70, consistent with prior readings, he said, and well within healthy recommended levels of below 120/80. "If I don't get this blubber off me, it won't stay that way," he said. He said he just needed a little motivation. Mrs. Gordon punched Mr. Tripoli's risk-factor numbers and other data into a software program she developed called Intimal Health. Based on evidence from clinical studies, it prints out recommendations customized to each patient as a guide to healthy habits that can help rejuvenate their arteries. She asked him to come back in six weeks for a progress report, when adding a cholesterol-lowering statin would be considered.
"Everything we do—diet, exercise, the medications—they are geared toward improving the environment that the artery lives in," Mrs. Gordon told him.Using the traditional Framingham Risk Score, Mr. Tripoli's 10-year risk of a heart attack—bolstered by his favorable blood pressure reading—was a low 6%. While keeping vessels young is a focus of the clinic, Mrs. Gordon doesn't usually calculate a patient's vascular age. But in this case, she ran Mr. Tripoli's age, cholesterol numbers and blood pressure through the updated Framingham Heart risk score. The result: His arteries were equivalent to those of a 64-year-old man.
"That's striking," Mr. Tripoli said, indicating he was prepared to get it lower. "I'm one of those people who has a chance to avert a catastrophe."
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