Persistent Asthma Linked to Increased Risk for Heart Rhythm Disorder

People with persistent asthma could be at 1.5 times higher risk of developing a heart rhythm disorder called atrial fibrillation than those without asthma, new research shows.

The study used data collected on 6,615 people in six areas around the country who were followed for nearly 13 years. When the study started, none of the participants had heart disease. Researchers concluded that the 150 participants with persistent asthma – those who required medication daily to control their condition – were more likely to be diagnosed with AFib than those without asthma.

Inflammation is a risk factor for both asthma and AFib, and the study found people with persistent asthma had the highest levels of inflammation. But the research also suggests there may be more than inflammation connecting asthma to an irregular heartbeat.

“We initially suspected that the link between asthma and atrial fibrillation may be explained by high levels of common inflammation markers in the blood at the baseline of the study,” said study author Dr. Matthew Tattersall, an assistant professor of cardiovascular medicine at the University of Wisconsin in Madison. “These inflammation markers are higher in asthmatics and independently predict atrial fibrillation.”

But when he and his colleagues adjusted for those inflammation blood markers, the relationship between asthma and AFib did not significantly change, Tattersall said. That led them to believe “there may be specific unique patterns of inflammation not identified or even other non-inflammatory pathways that may be driving an increased risk.”

Previous studies done in other countries also have found a link between asthma and AFib. One study in Norway, with 54,567 adults, found having asthma was associated with a 38% increased risk of AFib.

The new study is the first in the U.S., according to study authors, and the first to include a racially diverse group of people; 27% of participants were African American, 12% Chinese and 22% Hispanic. The research was published Tuesday in the American Heart Association journal Circulation: Arrhythmia and Electrophysiology.

At least 5.2 million Americans are living with atrial fibrillation. The condition is marked by a quivering or irregular heartbeat called an arrhythmia. It can cause heart failure and other heart-related complications, as well as blood clots. If a clot leaves the heart and travels to the brain, it can cause a stroke.

People with untreated AFib are nearly five times more likely to have a stroke than those who do not have this heart problem.

Over 25 million Americans have asthma, a chronic disease caused by inflammation in the bronchial tubes, or airways, in the lungs. People with persistent asthma are prescribed daily controller medications to keep their airways from tightening up and prevent coughing, wheezing, shortness of breath or chest tightness.

Patients and doctors need to know about the association between asthma and AFib, said Dr. Marc Miller, a cardiac electrophysiologist and an assistant professor of cardiology at Icahn School of Medicine at Mount Sinai in New York City. But he cautioned the study doesn’t show asthma is causing AFib.

“The theory is they both have a common origin – systemic inflammation,” said Miller, who was not involved with the study. “But we don’t know if that is the reason asthma patients get atrial fibrillation or if it’s the therapies being used to treat the asthma that are inducing the atrial fibrillation.”

Tattersall said the connection between the two conditions suggests doctors should be talking to their asthma patients about the importance of heart-healthy behaviors, such as exercise, maintaining a healthy weight and eating a heart-healthy, low-sodium diet.

“Being aware there is this association means we need to help patients focus on these primary prevention things we know we should be doing but that are often the hardest things to do,” Tattersall said. “But they can help with asthma and they can also reduce risk for atrial fibrillation.”

Source: American Heart Association


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Cutting Out Alcohol May Reduce Atrial Fibrillation Episodes

Gene Emery wrote . . . . . . . . .

For people with atrial fibrillation, abstinence from alcohol may make the heart beat better.

Eliminating most alcohol consumption dramatically cuts the number of episodes of the potentially-deadly heart rhythm disturbance among moderate and heavy drinkers, according to results of a six-month Australian study of 140 volunteers published in The New England Journal of Medicine.

While atrial fibrillation (AF), or Afib, reappeared in 73% of the people who averaged 13 drinks per week, the rate dropped to 53% among patients in the abstinence group – who weren’t supposed to drink at all but, on average, consumed two drinks weekly.

In addition, among the people trying to abstain, it took longer for their next episode of Afib to occur.

“What this study shows is the potential impact of alcohol reduction or abstinence in people with symptomatic heart rhythm problems,” co-author Dr. Peter Kistler of The Alfred Hospital in Melbourne told Reuters Health by phone. People with Afib symptoms who have 10 drinks per week should be advised to abstain or reduce their alcohol use, he said.

“Alcohol is not only a marker of increased risk of AF (as shown before, based on observational studies), but it seems to be also a real risk factor for AF, because if we ‘treat’ (in this case stop taking alcohol), we have a significant reduction in both the AF burden and the recurrence of AF,” Dr. Renato Lopes, a professor of medicine at Duke University Medical Center in Durham, North Carolina, who wasn’t involved in the study, said in an email.

Afib occurs when the upper chambers of the heart beat erratically. It is the most common heart rhythm problem and a leading cause of stroke. In some people, it comes and goes. Symptoms include weakness, shortness of breath and palpitations.

Doctors try to treat it by controlling blood pressure and other factors, but the new study “presents a compelling argument for alcohol abstinence as part of the successful management of atrial fibrillation,” writes Dr. Anne Gillis of the University of Calgary in an editorial accompanying the study. “Nevertheless, the sobering reality is that for many persons with atrial fibrillation, total abstinence from alcohol may be a difficult goal to achieve.”

In fact, the researchers were originally planning to follow patients for 12 months, but they couldn’t find enough volunteers willing to abstain from alcohol for that long.

The findings are not completely surprising. Population-based research had suggested that every drink (12 ounces of beer, 5 ounces of wine or a 1.5 ounce of distilled spirits) increases the risk of atrial fibrillation by 8%. The new randomized trial was designed to be a definitive test.

The Kistler team found it typically took 120 days for Afib to reappear in the non-drinking group versus 87 days in the group that wasn’t instructed to reduce alcohol consumption.

At the six-month mark, the hearts of the drinkers spent 1.2% of the time in Afib versus 0.5% of the time among volunteers assigned to abstinence.

Two thirds of the volunteers were taking antiarrhythmic drugs. The group allowed to continue to drink reduced their alcohol consumption a bit anyway. In the abstinence group, 61% were able to cut out alcohol completely but one quarter of the volunteers couldn’t get their weekly consumption below two drinks per week.

“Those who completely abstained had more benefit or a greater reduction in atrial fibrillation compared to those who reduced their intake but continued to drink,” Kistler noted. “If we had had complete abstinence, I think the difference would have been even greater.”

The non-drinkers also lost an average of 8 pounds more than the drinkers and saw a significant drop in blood pressure.

Doctors often advise patients that having a drink a day can be good for the heart, but that should not apply to Afib patients, Kistler said. Even in patients with heart disease, the new results “still suggest that they reduce their alcohol intake substantially.”

Source: Reuters

Medications Used to Treat Atrial Fibrillation May Raise Risk of Falls and Fall-Related Injuries

For older adults, fainting and falls are serious health concerns. They can lead to injury, hospitalization, and other severe consequences. Having certain chronic conditions, as well as taking certain medications, can raise your risk of experiencing falls and fall-related injuries.

One condition that contributes to fainting and falls is atrial fibrillation. Atrial fibrillation occurs when the upper (atrial) part of your heart contracts rapidly and irregularly (fibrillates). Atrial fibrillation may be continuous or occasional and is the most common irregular heart rhythm in older adults. It occurs in three to five percent of people over age 65.

To prevent atrial fibrillation symptoms, health professionals may treat patients with medications to control their heart rate or rhythm. However, these medications can potentially raise the risk for falls and fainting, though the connection hasn’t studied significantly in the past.

To learn more, researchers in Denmark designed a study to learn more about the potential risk for falls and fainting among older adults taking medication for atrial fibrillation. Their study was published in the Journal of the American Geriatrics Society.

Using Danish health data, the researchers identified patients who were between the ages of 65 and 100 when they were first diagnosed with atrial fibrillation. The researchers examined the records of 100,935 atrial fibrillation patients 65 years or older who filled prescriptions for heart rhythm medications.

The researchers examined the medication the patients took to control their heart rhythms. Prescriptions were for beta-blockers, certain calcium channel blockers (diltiazem, verapamil), and digoxin. Other medications included amiodarone, flecainide, and propafenone.

Then the researchers looked for those patients who had emergency department visits or hospital admissions for fainting, fall-related injuries, or both. Fall-related injuries were defined as fractures of the thigh, elbow, forearm, wrist, shoulder or upper arm, pelvis, and skull, as well as major and minor head injuries.

The researchers followed the patients for about two and a half years. During the follow-up period:

  • 17,132 (17 percent) had a fall-related injury
  • 5,745 (5.7 percent) had a fainting episode
  • 21,093 (20.9 percent) had either a fall-related or fainting-related injury

There were 40,447 deaths without a fall-related injury or fainting episode, which accounted for 40.1 percent of study participants.

The researchers reported that the medication amiodarone was significantly associated with increased risk, whether it was prescribed alone or with other heart rhythm drugs. The medication digoxin was slightly associated with fall-related injuries.

The researchers also learned that people were at higher risk for an injury within the first 90 days of treatment, and especially within the first 14 days of treatment.

“Our findings add evidence that, for older patients with atrial fibrillation, treatment with amiodarone is associated with a higher risk of fall-related injuries and fainting,” said the researchers. Additionally, the amiodarone connection was strongest within the first two weeks of the treatment but still present after long-term treatment.

The researchers concluded that being informed on the adverse risks of a given treatment is crucial to make shared decisions and provide quality patient care.

This summary is from “Rate- or Rhythm in Older Atrial Fibrillation Patients: Risk of Fall-related Injuries and Syncope.” It appears online ahead of print in the Journal of the American Geriatrics Society.

Source: Health In Aging


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Should You Get Pills or Surgery for Atrial Fibrillation?

Many older Americans have the worrisome and potentially dangerous irregular heartbeat known as atrial fibrillation, or “a-fib,” and they’re typically offered medicines or a surgery called ablation to correct it.

Which works best?

Two new trials may have the answer. Researchers say ablation and medicines perform similarly in protecting a-fib patients from stroke, death and other complications.

However, ablation may beat out drug therapy over the long term, reducing recurrences of a-fib and related hospitalizations for years to come, researchers say.

Patients who got ablation — where a catheter is used to tweak the heart muscle cells responsible for the arrhythmia — also seemed to have less shortness of breath, less fatigue and all-around better quality of life five years later, compared to those who got drug therapy alone.

The quality-of-life trial, “because of its size and duration, provides extraordinary new data regarding the patient’s perspective,” said Dr. Yves Rosenberg.

He was program officer for the study, and is also chief of the Atherothrombosis and Coronary Artery Disease Branch at the U.S. National Heart, Lung, and Blood Institute (NHLBI), which helped fund both trials.

A cardiologist who reviewed the findings said the data should reassure patients.

“I think the takeaway from this study is that catheter ablation is effective and safe for treating atrial fibrillation,” said Dr. Laurence Epstein, who directs electrophysiology at Northwell Health in Manhasset, N.Y.

“If you have atrial fibrillation and are symptomatic, ablation is a reasonable first-line option, as opposed to taking drugs,” he said.

Treatment pros and cons

According to the NHLBI, a-fib affects at least 2.7 million Americans and can lead to stroke, heart failure, and even mental impairment. Symptoms include rapid heart palpitations (“flip-flops” or skips); fatigue; shortness of breath, and difficulty doing physical activity.

“Since current drug therapies often have limited effectiveness in controlling atrial fibrillation, it is very important to understand whether ablation, an invasive procedure, yields better outcomes,” Dr. David Goff, director in the division of cardiovascular sciences at the NHLBI, said in an institute news release.

As Epstein explained, during ablation, “long catheters — wires with electrodes on them — are placed into the heart via the large veins in the groin. Radio waves are delivered from the catheter to the heart muscle, which causes heat and the controlled destruction of the muscle cells responsible for causing atrial fibrillation.”

Sometimes ablation is performed using tiny balloons that freeze the heart muscle to create the same effect.

Of course, no treatment is foolproof. “Depending on the patient the procedure can be as effective as 80-90 percent,” Epstein said, “but in others, at best, 50 percent.”

Many other patients get drug therapy alone to control the aberrant heart rhythm. But Epstein said outcomes are often “disappointing because the drugs do not work that well and that they can cause ‘pro-arrhythmia.’

“Pro-arrhythmia is when a drug used to treat an abnormal heart rhythm can actually cause a worse, more dangerous heart rhythm,” he explained.

Long-term benefits

To settle the meds-versus-ablation debate, the NHLBI helped conduct these two trials, which included more than 2,200 patients treated at 126 sites in the United States, Canada, Asia and Europe.

Half the patients had ablation and half were put on drug therapy, but could have ablation if their a-fib symptoms could not be controlled with medication — something known as “intent to treat.”

In the end, about 27 percent of the patients who started on drug therapy did end up undergoing ablation.

The median follow-up of patients in the trial was about four years.

“While data from the trial did not show that ablation was superior to drug therapy in reducing rates of deaths and strokes, it showed reduced recurrence of atrial fibrillation, as well as reductions in hospitalizations,” Rosenberg said in the news release.

The researchers noted that the overall rate of deaths and strokes was lower than expected. Also, about 9 percent of the patients assigned to receive ablation did not, in the end, undergo the procedure.

So, “when we examined the data according to the treatment actually received, the ablation group had significantly lower rates of death as well as the combination of death, disabling stroke, serious bleeding, or cardiac arrest compared with patients who only received drug therapy,” said study principal investigator Dr. Douglas Packer. He’s a cardiologist and professor of medicine at Mayo Clinic in Rochester, Minn.

The research team found that 12 months after the start of treatment, both groups of patients had at least some improvement in their quality of life. However, those in the ablation group had a larger decline in symptoms such as fatigue and shortness of breath, and their boost in quality of life lasted through five years of follow-up.

At the start of the study, 86 percent of patients in the ablation group and 84 percent on drug therapy reported atrial fibrillation symptoms during the previous month. By the end of the study, only 25 percent of patients in the ablation arm and 35 percent of those on drugs only reported symptoms.

Patients with the most severe symptoms at the start of the study had much greater improvement after ablation than those who initially had mild symptoms, the researchers added.

Dr. Satjit Bhusri is a cardiologist at Lenox Hill Hospital in New York City. Reviewing the new data, he said that the trials give doctors and patients valuable guidance.

First of all, he said, if your a-fib isn’t so bad that it harms your quality of life, perhaps controlling it with medicines alone might work. However, when quality of life is affected, a move to ablation therapy may be warranted, Bhusri said.

For his part, Epstein believes “we certainly need to continue to study these findings. As technology continues to advance, and ablation procedures become safer and more effective, ablation will most certainly become the treatment of choice.”

The papers were published in the Journal of the American Medical Association.

Source : HealthDay

Low-Carb Diet Tied to Common Heart Rhythm Disorder

Low-carb diets are all the rage, but can cutting carbohydrates spell trouble for your heart? People getting a low proportion of their daily calories from carbohydrates such as grains, fruits and starchy vegetables are significantly more likely to develop atrial fibrillation (AFib), the most common heart rhythm disorder, according to a study being presented at the American College of Cardiology’s 68th Annual Scientific Session.

The study, which analyzed the health records of nearly 14,000 people spanning more than two decades, is the first and largest to assess the relationship between carbohydrate intake and AFib. With AFib, a type of arrhythmia, the heart doesn’t always beat or keep pace the way it should, which can lead to palpitations, dizziness and fatigue. People with AFib are five times more likely to have a stroke than people without the condition. It can also lead to heart failure.

Restricting carbohydrates has become a popular weight loss strategy in recent years. While there are many different low-carbohydrate diets including the ketogenic, paleo and Atkins diets, most emphasize proteins while limiting intake of sugars, grains, legumes, fruits and starchy vegetables.

“The long-term effect of carbohydrate restriction is still controversial, especially with regard to its influence on cardiovascular disease,” said Xiaodong Zhuang, MD, PhD, a cardiologist at the hospital affiliated with Sun Yat-Sen University in Guangzhou, China, and the study’s lead author. “Considering the potential influence on arrhythmia, our study suggests this popular weight control method should be recommended cautiously.”

The findings complement previous studies, several of which have associated both low-carbohydrate and high-carbohydrate diets with an increased risk of death. However, while previous studies suggested the nature of the non-carbohydrate component of the diet influenced the overall pattern observed, the new study did not.

“Low carbohydrate diets were associated with increased risk of incident AFib regardless of the type of protein or fat used to replace the carbohydrate,” Zhuang said.

Researchers drew data from Atherosclerosis Risk in Communities (ARIC), a study overseen by the National Institutes of Health that ran from 1985-2016. Of the nearly 14,000 people who did not have AFib when they enrolled in the study, researchers identified nearly 1,900 participants who were subsequently diagnosed with AFib during an average of 22 years of follow-up.

Study participants were asked to report their daily intake of 66 different food items in a questionnaire. The researchers used this information along with the Harvard Nutrient Database to estimate each participant’s daily carbohydrate intake and the proportion of daily calories that came from carbohydrates. On average, carbohydrates comprised about half of calories consumed. The Dietary Guidelines for Americans recommend that carbohydrates make up 45 to 65 percent of total daily calorie intake.

Researchers then divided participants into three groups representing low, moderate and high carbohydrate intake, reflecting diets in which carbohydrates comprised less than 44.8 percent of daily calories, 44.8 to 52.4 percent of calories, and more than 52.4 percent of calories, respectively.

Participants reporting low carbohydrate intake were the most likely to develop AFib. These participants were 18 percent more likely to develop AFib than those with moderate carbohydrate intake and 16 percent more likely to develop AFib than those with high carbohydrate intake.

Several potential mechanisms could explain why restricting carbohydrates might lead to AFib, Zhuang said. One is that people eating a low-carbohydrate diet tend to eat fewer vegetables, fruits and grains—foods that are known to reduce inflammation. Without these foods people may experience more inflammation, which has been linked with AFib. Another possible explanation is that eating more protein and fat in lieu of carbohydrate-rich foods may lead to oxidative stress, which has also been associated with AFib. Finally, the effect could be related to an increased risk of other forms of cardiovascular disease.

Zhuang said that while the research shows an association, it cannot prove cause and effect. A randomized controlled trial would be needed to confirm the relationship between carbohydrate intake and AFib and assess the effect in a more ethnically diverse population. In addition, the study did not track participants with asymptomatic AFib or those who had AFib but were never admitted to a hospital, nor did it investigate different subtypes of AFib, so it is unknown whether patients were more likely to have occasional episodes of arrhythmia or persistent AFib. The study did not account for any changes in diet that participants may have experienced after completing the questionnaire.

Source: American College of Cardiology