Doc: It’s risk versus reward in ‘heart scan’ case
Dear Dr. Roach: I know so many people who have had a heart attack and open heart/bypass surgery due to blocked arteries. Isn’t there a test or scan we can have done every five years or so to check our arteries and be proactive about this before a heart attack happens? We have colonoscopies; why not a heart scan?
Dear G.T.: It’s an entirely reasonable question. However, before committing to a screening program, one has to ask whether the potential benefits outweigh the harms of the screening test. Then finally, one looks at the outcomes of people in a screening program compared with those who don’t get screening.
There are several candidates for a heart screening test. The most evidence is on either a test of heart function (such as a stress test) or a heart scan, which looks at the anatomy of the heart vessels (such as a CT or MRI scan). None of these is perfect. They can have a false-positive result, meaning they say you have heart blockages when you don’t. This can lead to unneeded medication and even procedures. The tests also may have a false-negative result, which means you might not get the treatment to prevent a heart attack or it might keep people from going to the ER when they have heart attack symptoms.
Since screening, by definition, is done in people with no symptoms, there must be a high degree of certainty that there is a net benefit before recommending it to the population. So far, the studies have shown no benefit in screening for coronary artery disease, and so I don’t recommend it in general.
However, for some people who are at high risk, such as those with a strong family history or multiple risk factors, it is reasonable to consider a screening test on an individual basis. It is also reasonable in high-risk individuals to treat them as though they have blockages in their arteries, with interventions as needed on their diet, exercise pattern, strategies for dealing with stress, aspirin, a statin medication and possibly a beta blocker. People at high risk should discuss these options with their doctor.
Dr. Roach writes: A reader sent me a 24-page booklet he received in the mail asking whether a “tiny pill could put your doctor out of business.” I’ve seldom seen such hyperbole, with promises to help all the organs of the body, curing baldness, eliminating irritable bowel and washing away “years of toxins” from the liver. It was a multivitamin and mineral supplement. While some people with a poor diet may benefit from multivitamins, studies have repeatedly shown that multivitamins do not improve lifespan or reduce disease risk. (There may be an exception in vitamin D, for which studies are ongoing. Many people have low vitamin D, and if associated with symptoms or with low bone density, vitamin D supplementation is clearly indicated.)
Apart from vitamin D in some, people with no symptoms do not need supplements, so long as they have a healthy diet. The liver and kidneys are sufficient to remove toxins. As always, something that seems too good to be true probably is.
Email questions to ToYourGoodHealth@med.cornell.edu.