Kidney Disease May Boost Risk of Abnormal Heartbeat

Dennis Thompson wrote . . . . . . .

People with failing kidneys are at increased risk of developing a life-threatening abnormal heart rhythm, a new report suggests.

Chronic kidney disease can as much as double a patient’s risk of atrial fibrillation, a quivering or irregular heartbeat that can lead to stroke or heart failure, said lead researcher Dr. Nisha Bansal. She is an associate professor of nephrology at the University of Washington’s Kidney Research Institute, in Seattle.

The risk of atrial fibrillation increases as kidney function declines, Bansal said.

“We saw the worse your kidney function, the greater your risk of developing atrial fibrillation. Even mild changes in kidney function were strongly linked to atrial fibrillation,” Bansal noted.

The study included data gathered from three separate research projects focused on heart health in the United States. The three projects created a combined pool of almost 17,000 patients with follow-up periods averaging between 8.5 years and 12.5 years. None of the participants had atrial fibrillation when first recruited.

Each project checked participants’ kidney function when they first joined the study, using one or two different lab tests. One was a blood test that evaluated how well the kidneys were removing toxins from the bloodstream. The other was a urine test that assessed whether the kidneys were properly filtering out a specific protein.

People with worse kidney function at the start of the study were more likely to have atrial fibrillation by the end, the researchers found. Those who did worse on the blood test were twice as likely to develop an abnormal heart rhythm, while those who did worse on the urine test were 76 percent more likely.

While the association doesn’t prove a cause-and-effect relationship, the link remained even after the researchers took into account other risk factors for atrial fibrillation, such as diabetes, tobacco use and a history of heart problems.

“We found that kidney function was independent of all other risk factors,” Bansal said.

Research has not yet been conducted to explain the association between kidney function and atrial fibrillation, Bansal noted, but there are a number of possible explanations.

A poorly functioning kidney can alter blood levels of a number of nutrients needed to maintain proper heart function, such as potassium, vitamin D, calcium and phosphorus, Bansal said.

The kidneys also are responsible for maintaining a steady volume of blood in your body, removing excess fluid by way of urination.

“If your kidney function is impaired, your blood volume increases,” Bansal said. “That increased stress on your heart causes it to stretch and can also trigger this abnormal heart rhythm.”

Dr. Kevin Chan, a nephrologist with Massachusetts General Hospital in Boston, noted that it’s also possible toxins that haven’t been filtered from the blood — thanks to a bad kidney — might have some as-yet-unknown effect on heart function.

Based on this report, doctors treating patients with kidney disease should keep an eye out for potential heart problems, said Chan, who was not involved with the new study.

“Physicians should be cognizant of this relationship so they are attuned to recognizing atrial fibrillation when they see their chronic kidney disease patients,” Chan said.

Doctors can reduce a person’s risk of stroke from atrial fibrillation by putting them on blood thinners, he added. Atrial fibrillation patients also can be fitted with a pacemaker, or undergo a procedure to restore proper heart rhythm.

People with kidney disease could help themselves by adopting a heart-healthy lifestyle, Bansal suggested, for example, eating right, exercising and quitting smoking.

“A heart-healthy lifestyle does improve your risk of all kinds of cardiovascular disease, as well as kidney disease, so I would recommend that,” Bansal advised.

The report was published online in the Clinical Journal of the American Society of Nephrology.

Source: HealthDay

Aspirin Safe for Heart Failure Patients, Study Finds

Amy Norton wrote . . . . . .

Some research has raised concerns about the safety of aspirin for heart failure patients. But a new study appears to offer some reassurance.

The study, of over 2,300 patients, found that those on daily aspirin were not at heightened risk of being hospitalized for, or dying from, heart failure.

That has been a concern because, in theory, aspirin could interfere with the benefits of certain heart failure drugs, explained Dr. Shunichi Homma, the senior researcher on the study.

Plus, two past studies have linked aspirin use to an increased risk of heart failure complications.

But the new study, which compared aspirin to warfarin, a blood thinner, was larger and longer-term — following patients in 168 centers in 11 countries over 10 years.

“I think this should allay fears that there might be a detrimental effect of prescribing aspirin,” said Homma. He is deputy chief of cardiology at New York-Presbyterian/Columbia University Medical Center, in New York City.

Homma and his colleagues reported the findings in the July 31 online issue of JACC: Heart Failure.

Dr. Christopher O’Connor is a cardiologist and editor-in-chief of the journal.

He agreed that the findings are reassuring. Compared with the earlier, smaller studies, O’Connor said, “this one is probably closer to the truth.”

O’Connor said he thinks the results have “immediate implications” for heart failure care.

Close to 6 million Americans have heart failure, according to the U.S. Centers for Disease Control and Prevention.

It’s a chronic condition in which the heart muscle can no longer pump blood efficiently enough to meet the body’s needs. That causes symptoms such as fatigue, breathlessness and swelling in the limbs.

Often, heart failure is caused by damage to the heart muscle from a heart attack or coronary artery disease. And, in general, those patients should be on aspirin to limit the risk of a first-time or repeat heart attack, O’Connor said.

The trouble is, there have been concerns that aspirin could interfere with ACE inhibitors or angiotensin receptor blockers (ARBs) — two drug classes that are key in managing heart failure. Those drugs boost compounds called prostaglandins in the blood, whereas aspirin reduces them.

For the new study, Homma’s team analyzed data from a clinical trial in which heart failure patients were randomly assigned to take either aspirin or warfarin, which is used to prevent blood clots.

Patients in the aspirin group took 325 milligrams per day.

Over 10 years, just over 19 percent of aspirin patients were hospitalized for heart failure, or died of the disease. That compared with just under 23 percent of warfarin users, the findings showed.

Homma’s team also accounted for other factors, including patients’ age and heart disease severity. In the end, there was no statistical difference between the two groups in their risk of heart failure complications.

To O’Connor, the bottom line for heart failure patients is straightforward: “If you’re on aspirin for a guideline-recommended indication,” he said, “keep taking it.”

Of course, aspirin is not without risks. It can cause bleeding in the digestive tract, or even contribute to a hemorrhagic (bleeding) stroke.

So patients should never take aspirin on their own, without a doctor’s guidance, Homma said.

Dr. Susan Graham, a cardiologist who also worked on the study, made a broader point: Heart patients — and older adults, in general — are often taking many prescription drugs at any given time.

“That speaks to the importance of studying potential drug interactions,” said Graham, a professor of medicine at the University at Buffalo, in New York.

“We have to stay on our toes to make sure that we’re doing the right thing,” she said.

Homma and some of his colleagues on the study reported receiving research funding or fees from the pharmaceutical industry.

Source: HealthDay


Before Using Aspirin to Lower Your Risk of Heart Attack or Stroke, What You Should Know

Only a health care provider can determine whether regular use of aspirin will help to prevent a heart attack or stroke in your particular case. Aspirin can prevent these problems in some people but not in everyone, and it has important side effects. You should use daily aspirin therapy only after first talking to your health care provider, who can weigh the benefits and the risks.

Aspirin is often thought of as a harmless over-the-counter (OTC) drug that’s been relied on for years to treat pain and fever. Now you’re hearing that it can also lower your risk of a heart attack and some kinds of strokes. Aspirin may seem like a quick-and-easy way to decrease these risks, but it’s not as simple as you think.

What Studies Show

Since aspirin was discovered more than a century ago, it has played a major role in treating headaches, fevers, and minor aches and pains for millions of people. Now studies show that because aspirin thins the blood, it can also help to lower the chances of a heart attack or a stroke caused by a blood clot in the brain. But research has found it works only in certain people, specifically those who had a previous heart attack or stroke, or have disease of the blood vessels in the heart. It does not seem to work in people with healthier hearts and blood vessels.

Most health professionals agree that long-term aspirin use to prevent a heart attack or stroke in healthy people is unnecessary. If you are using aspirin to lower these risks and have not talked with a health professional about it, you may be putting your health at risk. You should ONLY use daily aspirin therapy under the guidance of a health care provider.

Not Without Risks

Aspirin has been known to help people living with some diseases of the heart and blood vessels. It can help prevent a heart attack or clot-related stroke by interfering with how the blood clots. But the same properties that make aspirin work as a blood thinner to stop it from clotting may also cause unwanted side effects, including bleeding into the brain or stomach.

Aspirin also can mix badly with prescription medicines and over-the-counter drugs. People already using a prescription medicine that thins the blood such as warfarin, dabigatran (Pradaxa) and rivaroxaban (Xarelto) should always talk to a health professional before using aspirin, even occasionally.

Discuss the use of all medicines, vitamins, and dietary supplements with your health professional before taking aspirin daily. He or she will decide if the benefits of taking daily aspirin outweigh the risks in your particular case and can provide medical knowledge and guidance to help prevent unwanted side effects.

Dose Matters

Whatever purpose you are using daily aspirin for, how much you take matters. It’s important to your health and safety that the dose you use and how often you take it is right for you. Your health professional can tell you the dosing and directions that will provide the greatest benefit with the least side effects.

Not all over-the-counter pain relievers contain aspirin. If your health care provider prescribes daily aspirin to lower the risk of a heart attack and clot-related stroke, read the labels carefully to make sure you have the right product. Some drugs combine aspirin with other pain relievers or other ingredients and should not be used for long-term aspirin therapy. If you have questions talk to a health professional.

Before you use aspirin to lower your risk of heart attack and stroke, talk to a health professional. It could save your life.

Source: U.S. Department of Health and Human Services


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Gaining A Few Pounds May Increase Long-term Heart Failure Risk

Gaining even a little weight over time may alter the structure and function of heart muscle, affecting long-term risk of heart failure, according to new research in Journal of the American Heart Association, the Open Access Journal of the American Heart Association/American Stroke Association.

Researchers followed 1,262 adults (average age 44, 57 percent women, 44 percent black, 36 percent obese) who were free from heart disease and other conditions that put them at high risk for heart disease for seven years. Participants had MRIs scans of their hearts and multiple body fat measurements at the start of the study and then seven years later.

Researchers found those who gained weight:

  • even as little as 5 percent, were more likely to have thickening and enlargement of the left ventricle, well-established indicators of future heart failure;
  • were more likely to exhibit subtle decreases in their hearts’ pumping ability; and
  • were more likely to exhibit changes in heart muscle appearance and function that persisted even after the researchers eliminated other factors that could affect heart muscle performance and appearance, including high blood pressure, diabetes, smoking and alcohol use.

Conversely, people who lost weight were more likely to exhibit decreases in heart muscle thickness.

Notably, how much a person weighed at the beginning of the study didn’t impact the changes, suggesting that even those of normal weight could experience adverse heart effects if they gain weight over time, researchers said.

“Any weight gain may lead to detrimental changes in the heart above and beyond the effects of baseline weight so that prevention should focus on weight loss or if meaningful weight loss cannot be achieved – the focus should be on weight stability,” said Ian Neeland, M.D., study senior author and a cardiologist and assistant professor of medicine at University of Texas Southwestern Medical Center in Dallas, Texas. “Counseling to maintain weight stability, even in the absence of weight loss, may be an important preventive strategy among high-risk individuals.”

The researchers caution that their study was relatively small and their findings do not mean that every person with weight gain will necessarily develop heart failure. The results do suggest that changes in weight may affect heart muscle in ways that can change the organ’s function.

Further research is needed to determine whether aggressive weight management could, reverse the changes, Neeland said.

Source : American Heart Association


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Artificial Sweeteners Linked to Risk of Weight Gain, Heart Disease and other Health Issues

Artificial sweeteners may be associated with long-term weight gain and increased risk of obesity, diabetes, high blood pressure and heart disease, according to a new study published in CMAJ (Canadian Medical Association Journal).

Consumption of artificial sweeteners, such as aspartame, sucralose and stevia, is widespread and increasing. Emerging data indicate that artificial, or nonnutritive, sweeteners may have negative effects on metabolism, gut bacteria and appetite, although the evidence is conflicting.

To better understand whether consuming artificial sweeteners is associated with negative long-term effects on weight and heart disease, researchers from the University of Manitoba’s George & Fay Yee Centre for Healthcare Innovation conducted a systematic review of 37 studies that followed over 400,000 people for an average of 10 years. Only 7 of these studies were randomized controlled trials (the gold standard in clinical research), involving 1003 people followed for 6 months on average.

The trials did not show a consistent effect of artificial sweeteners on weight loss, and the longer observational studies showed a link between consumption of artificial sweeteners and relatively higher risks of weight gain and obesity, high blood pressure, diabetes, heart disease and other health issues.

“Despite the fact that millions of individuals routinely consume artificial sweeteners, relatively few patients have been included in clinical trials of these products,” said author Dr. Ryan Zarychanski, Assistant Professor, Rady Faculty of Health Sciences, University of Manitoba. “We found that data from clinical trials do not clearly support the intended benefits of artificial sweeteners for weight management.”

“Caution is warranted until the long-term health effects of artificial sweeteners are fully characterized,” said lead author Dr. Meghan Azad, Assistant Professor, Rady Faculty of Health Sciences, University of Manitoba. Her team at the Children’s Hospital Research Institute of Manitoba is undertaking a new study to understand how artificial sweetener consumption by pregnant women may influence weight gain, metabolism and gut bacteria in their infants.

“Given the widespread and increasing use of artificial sweeteners, and the current epidemic of obesity and related diseases, more research is needed to determine the long-term risks and benefits of these products,” said Azad.

Source: Science Daily

Long Working Hours Increases the Risk of Developing Atrial Fibrillation

People who work long hours have an increased risk of developing an irregular heart rhythm known as atrial fibrillation, according to a study of nearly 85,500 men and women published in the European Heart Journal today (Friday).

The study showed that, compared to people who worked a normal week of between 35-40 hours, those who worked 55 hours or more were approximately 40% more likely to develop atrial fibrillation during the following ten years. For every 1000 people in the study, an extra 5.2 cases of atrial fibrillation occurred among those working long hours during the ten-year follow-up.

Professor Mika Kivimaki, director of the Whitehall II Study, from the Department of Epidemiology at University College London (UK), who led the research, said: “These findings show that long working hours are associated with an increased risk of atrial fibrillation, the most common cardiac arrhythmia. This could be one of the mechanisms that explain the previously observed increased risk of stroke among those working long hours. Atrial fibrillation is known to contribute to the development of stroke, but also other adverse health outcomes, such as heart failure and stroke-related dementia.”

Prof Kivimaki and colleagues from the Individual-Participant-Data Meta-analysis in Working Populations (IPD-Work) Consortium analysed data from 85,494 men and women from the UK, Denmark, Sweden and Finland who took part in one of eight studies in these countries. They assessed the participants’ working hours when they joined the studies between 1991 and 2004. Working hours were classified as less than 35 hours a week, 35-40 hours, which was considered as the standard working hours of full-time workers, 41 to 48 hours, 49 to 54 hours, and 55 hours or more a week. None of the participants had atrial fibrillation at the start of the studies.

During the ten-year follow-up period, there were 1061 new cases of atrial fibrillation. This gave an incidence rate of 12.4 per 1000 people in the study, but among the 4,484 people working 55 hours or more, the incidence was 17.6 per 1000. “Those who worked long hours had a 1.4 times higher risk of developing atrial fibrillation, even after we had adjusted for factors that could affect the risk, such as age, sex, socioeconomic status, obesity, leisure time physical activity, smoking and risky alcohol use,” said Prof Kivimaki.

“Nine out of ten of the atrial fibrillation cases occurred in people who were free of pre-existing or concurrent cardiovascular disease. This suggests the increased risk is likely to reflect the effect of long working hours rather than the effect of any pre-existing or concurrent cardiovascular disease, but further research is needed to understand the mechanisms involved.

“A 40% increased extra risk is an important hazard for people who already have a high overall risk of cardiovascular disease due to other risk factors such as older age, male sex, diabetes, high blood pressure, high cholesterol, overweight, smoking and physical inactivity, or living with an established cardiovascular disease. For a healthy, young person, with few if any of these risk factors, the absolute increased risk of atrial fibrillation associated with long working hours is small.”

The study does have some limitations, including the fact that working hours were only assessed once at the beginning of the study and that the type of job (for instance, whether it involved working night shifts) was not recorded.

Source: European Society of Cardiology


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