Blood Pressure Archive

Yes, but only under very unusual circumstances. Unless you have a rare inherited heart condition, consider these examples as curiosities rather than cause for concern.

If you take a statin, you've probably noticed the bright yellow sticker on the back of the prescription bottle warning you to avoid grapefruit and grapefruit juice. This tangy citrus fruit contains compounds that interfere with enzymes that break down various medications, including statins. This can boost blood levels of the drug, which could increase the risk of side effects.

It turns out that grapefruit also contains a substance called naringenin that can cause subtle changes in the heart's carefully choreographed timing. It does this by slightly prolonging what's known as the QT interval (see "What is long QT syndrome?"). To be clear, this phenomenon only happened in some volunteers after they drank about four cups of grapefruit juice. But a handful of other substances can have a similar effect, as described in an article about these so-called arrhythmogenic foods in the July 2020 issue of Trends in Cardiovascular Medicine.

Many provide links to published research about these heart -protecting drugs. Others mention personal beliefs about statins, some of which are inaccurate.

Statins are among the most frequently prescribed medications in the United States. These cholesterol-lowering drugs help reduce the risk of heart attacks and strokes, especially for people who've already had one of those life-threatening events. But many people stop taking their statins or don't take them as prescribed, a phenomenon doctors refer to as nonadherence.

Hoping to gain some insight into this trend, researchers analyzed 11,852 posts that mentioned statins on Twitter over a five-year period. About a quarter of Americans use Twitter, which is one of the most popular social media platforms. Although many of the tweets featured ads or financial market information, nearly half were related to health issues associated with statins. Of these, more than a third provided resource information, such as a link to a published study. About 20% included personal beliefs or attitudes about statins, which proved to be quite polarized. Some people described statins as lifesaving, while others referred to them as poisonous or deadly, according to the researchers, whose study was published June 25, 2020, in JAMA Network Open.

More than 10 million adults in the US have hypothyroidism — when the thyroid gland fails to produce enough thyroid hormone to meet the body’s needs — but the vast majority of these cases are considered mild. Whether or not to treat mild hypothyroidism is an ongoing debate. There is a possible link between mild hypothyroidism and coronary artery disease, but researchers found that treating it in older people did not provide any benefit.

News briefs

Here's a finding worth toasting if you're partial to a tipple: a study published online June 29, 2020, by JAMA Network Open linked low-to-moderate alcohol drinking in middle age with better cognitive (thinking) skills in older age. Researchers analyzed the health data of about 20,000 adults (average age 61) who took part in cognitive screenings every few years during a nine-year period and reported how much alcohol they drank each week. Men who had fewer than 15 drinks per week, and women who had fewer than eight drinks per week, were considered moderate drinkers. And they're the ones who appeared to have better word recall and vocabulary over time, and slower rates of cognitive decline, compared with people who never drank. The study is observational and doesn't prove that drinking alcohol protects the brain. In fact, the subject is debated: some studies have suggested that moderate alcohol drinking is associated with better cardiovascular health compared with heavy alcohol intake, but other studies have found that drinking any amount of alcohol increases the risk for high blood pressure and stroke. The takeaway: if you're going to raise a glass, do so only in moderation.

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Ask the doctor

Q. My husband is reluctant to get tested for sleep apnea. But I'm pretty sure that he has it, and I'm concerned because I've heard that it can contribute to heart disease. How are these two conditions connected?

A. As you likely know already, people with sleep apnea may snore loudly and may also periodically gasp for breath throughout the night. These explosive snorts often wake up bed partners or roommates — although not necessarily the person with apnea.

From badminton to pickleball to tennis, hitting objects across a net can be a fun, effective way to get in shape.

Looking for an exercise that gets your heart pumping and strengthens muscles in your legs, arms, and core? Tennis and other racquet sports can serve up all those benefits and more. In fact, several long-running studies have linked racquet sports to a lower risk of cardiovascular disease and a longer life.

"Playing tennis is an amazing workout. And no matter how good you are, you can have fun doing it," says Joe DiVincenzo, a physical therapist at Harvard-affiliated Spaulding Rehabilitation Hospital and former competitive tennis player. In general, racquet sports engage muscles throughout your upper and lower body, which challenges your heart. During a match, you do frequent, short bursts of high-intensity activity interspersed with less vigorous movements — a perfect example of interval training. Also known as HIIT (high-intensity interval training), this workout strategy seems to be a good way to boost cardiovascular fitness.

In the journals

Lowering high blood pressure with medication is good for the brain as well as the heart, suggests a study published online May 19, 2020, by JAMA.

Scientists reviewed 14 trials involving more than 96,000 people who had their high blood pressure monitored without medication vs. those who took one or more blood pressure drugs, such as beta blockers, ACE inhibitors, and angiotensin-receptor blockers. Almost 58% were men, and the average age was 69. The people were tested for dementia or cognitive impairment (trouble learning a new task, concentrating, or making decisions) before taking medication. They were tested again an average of four years later.

High blood pressure can damage the brain in several ways. Treating this common problem can protect your mind as well as your heart.

High blood pressure seldom causes any symptoms. But over time, the excessive force and friction of blood pushing against the inner walls of the arteries can damage blood vessels throughout the body. And while the biggest threat may be to your heart, your brain can also suffer.

Even slightly elevated blood pressure in middle age has been linked to a 30% higher risk of dementia two decades later. But taking blood pressure drugs may help people avoid that risk, according to a study in the May 19, 2020, issue of JAMA.

Researchers are beginning to better understand if, when, and how to address this condition, which is linked to a newly recognized type of stroke.

In the womb, all fetuses have a foramen ovale (Latin for "oval hole") between the heart's right and left upper chambers (atria). This opening allows blood to take a shortcut within the heart rather than following a longer path through the lungs, which cannot work until they are exposed to air. After birth, when a newborn baby takes his or her first breath, the foramen ovale begins to close. Most of the time, it seals completely within a few months.

But in about a quarter of people, that doesn't happen. This anatomical variation is called a patent foramen ovale (patent means open) or PFO. Most people never know they have it, because a PFO doesn't cause any signs or symptoms. For the most part, the condition is harmless.

Studies of drugs, diets, and devices all come with their own unique set of challenges.

The best way to know if a new medical treatment truly works is with a randomized controlled trial — the "gold standard" of research studies, also known simply as a clinical trial. Volunteers are randomly assigned to receive either the new treatment or the comparison, which may be a placebo (an inactive therapy) or a treatment that's already available.

As the nation's top cause of death, cardiovascular disease has been at the leading edge of evidence generation, says Dr. Robert Yeh, director of the Smith Center for Outcomes Research in Cardiology at Harvard-affiliated Beth Israel Deaconess Medical Center. "We probably have more evidence for cardiovascular treatments than for any other field of medicine," he says. Among the studies with the greatest impact were the clinical trials that heralded new therapies to treat heart attacks. These include clot-dissolving drugs in the 1980s, followed in the 1990s by artery-opening angioplasty procedures, which remain the standard of care today. Stents, the tiny mesh tubes used in these procedures, have also been extensively studied in clinical trials (see "Testing devices: Different dilemmas").