Q: I feel fine, but how do I really know if my heart is healthy?
A: The amount of work the heart performs is mind-boggling. From birth until death, the heart beats nearly 3 billion times. Each heartbeat generates enough force to circulate blood through tens of thousands of miles of vessels. The amount of blood that passes through an average adult heart in a week could fill a backyard swimming pool.
When things go wrong with this vital organ, the outcome is often fatal. Cardiovascular disease claims 18 million lives – nearly one-third of all deaths – across the globe each year.
The good news is there are things we can do to keep our hearts healthy and working well.
Much of what we have learned about how to prevent heart disease comes from a study started in a small town in Massachusetts shortly after World War II. At the start of the Framingham Heart Study, researchers monitored approximately 5,000 healthy, mostly White patients between the ages of 30 and 59.
Framingham identified key risk factors for heart disease – family history, smoking, diabetes, high cholesterol and hypertension.
A 12-year study of 20,000 Swedish men showed that almost 4 out of 5 heart attacks could be prevented through Framingham-inspired lifestyle changes, such as a healthy diet, moderate alcohol consumption, no smoking, increased physical activity, and maintaining a normal body weight. Men who adopted all 5 changes were 86 percent less likely to have a heart attack than those who did not.
But as important as the Framingham Heart Study has been in advancing our understanding of heart disease, it does not tell the whole story. For example, Framingham risk models do not seem to apply equally to non-White ethnic groups. South Asians, for instance, have a very high prevalence of heart disease, even when they have 0 or only 1 Framingham risk factor. There may be novel risk factors in this and other populations.
Other ways to monitor your heart health include:
Lipoprotein(a): Lipoprotein(a) is a cholesterol-carrying molecule. A high serum concentration of lipoprotein(a), which can be measured on a standard blood test, is associated with more than double the normal risk of developing coronary artery disease or stroke. Other novel risk markers may include smaller and denser cholesterol particles that are more prone to causing arterial hardening.
C-reactive protein or CRP: This blood test looks for elevated levels of C-reactive protein, which go up with inflammation.
Coronary calcium scan: This CT scan can assess the degree of coronary calcium, a marker of arterial hardening. In this noninvasive test, X-ray-opaque dye is injected into a vein so any coronary grit can be visualized. An elevated calcium “score” is predictive of cardiac events, such as heart attacks, irrespective of other cardiac risk factors. The lower the score, the better. A calcium score of 0 means there is no evidence of heart disease, and a score from 1 to 10 suggests minimal evidence of disease. A score of 100 or more is associated with elevated risk of heart attack.
Patients can talk to their doctors about these tests. Patients with an elevated score on any of these tests may be prescribed a drug called a statin, which can lower cholesterol, reduce inflammation and has been shown to lower risk for heart attack or stroke.
Though some cardiologists advocate for a treadmill stress test to proactively evaluate risk, such tests typically only detect coronary blockages greater than 70 percent, which are unlikely to be present in patients who don’t have chest pains.
Other cardiovascular risk factors are in the “psychosocial” domain. A massive amount of epidemiological data associates heart disease with chronic emotional disorder.
For example, individuals in unhappy marriages are at a much higher risk for heart disease than those in more joyous unions. The risk of heart attack and death increases dramatically in the year following a broken romance.
Recent research has focused on the association of “negative affectivity” traits, such as depression, anxiety, and anger, with heart disease. The strongest evidence has emerged for depression, which seems to be an independent risk factor for coronary artery disease and increases the risk of poor outcomes, including death, after a heart attack.
How does depression affect heart health? Possible mechanisms include elevating blood pressure, causing vascular inflammation, and increasing blood clotting. Unhealthy behaviors associated with depression, such as physical inactivity, smoking, and failure to take medications or adhere to medical advice, also probably play a role.
It has been easier to focus on blood pressure and cholesterol as cardiovascular risk factors, in part because those factors are so much easier to reduce than emotional and social disruption. But we must keep psychosocial factors front and center in how we think about heart problems, too. It is increasingly clear that heart disease is inextricably linked to the state of our neighborhoods, jobs, families and minds.
So, if you want a healthy heart, exercise, eat right and don’t smoke. If you have elevated risk of heart disease, talk to your doctor about getting a coronary CT scan.
But also take good care of your interpersonal relationships and mental health. Pursuits such as yoga and meditation may be beneficial in this regard. Remember that your mind-set, your coping strategies and your capacity to transcend distress are also a matter of life and death.
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Sandeep Jauhar is a cardiologist at Northwell Health in New York and the author of “Heart: A History.” His new book, “My Father’s Brain: Life in the Shadow of Alzheimer’s,” will be released in April.