All Diabetics Should Take Statins, Say Experts

The European Association for the Study of Diabetes (EASD) has recommended that all people suffering from diabetes should be taking statins, as research showed that the evidence for their effectiveness in reducing cardiovascular risk in diabetics, and even people without diabetes, is incontrovertible.

Professor John Betteridge, of University College London Medical School, pointed out at the EASD annual meeting in September 2010 that all people with diabetes should be taking statins to reduce their chances of having a heart attack or stroke, although he also warned that they should avoid any drug interactions with other medications being taken.

Betteridge has analysed a number of studies into the use of statins, such as the CollaborativeAtoRvastatin Diabetes Study (CARDS), funded by Diabetes UK, the Department of Health and Pfizer, which examined their benefits in people with type 2 diabetes who did not already have evidence ofcardiovascular disease .

In the CARDS study, atorvastatin 10mg/day was shown to reduce major cardiovascular events by 37 per cent and strokes by 48 per cent, reinforcing guidelines issued by the Joint British Society (JBS) regarding targets for low-density lipoprotein cholesterol in this high-risk group.

Betteridge argues that statins are safe if taken appropriately and drug interactions avoided, as they can lead to serious side effects, especially when patients are on a variety of drug treatments. Statins should also not be used by pregnant women at least six weeks before conception.

He realises that statins don’t always get a good press, and that many diabetics will be wary of this advice, but he points out that the evidence shows them to be highly effective in preventing major vascular events in patients with diabetes.

However, the idea of taking statins to offset the effects of junk food has been criticised by diabetes experts. New research had recommended that fast food outlets should give out free statin pills as a way of combating the impact of unhealthy food, as they can reduce the levels of bad cholesterol in the blood, which is why they are normally prescribed to decrease the risk of cardiovascular disease.

There are now worries that using statins could encourage people to lead unhealthier lives, eat more fast food and therefore increase the risk of developing type 2 diabets. Although studies have found that a single, cheap statin pill could offset the increased risk to the heart caused by the fat in a cheeseburger and a small milkshake, there are concerns that it is both irresponsible and dangerous to promote their use as a quick fix to counteract the effects of an unhealthy diet.

Zoe Harrison, Care Advisor at the charity Diabetes UK, said Statins can reduce the risk of cardiovascular disease by lowering the bad cholesterol in our blood which can be raised due to a high-fat diet. However, they don't prevent all the side effects that result from an excessive intake of fatty food.

Statins also have some serious side effects - such as damage to the liver, pancreas and muscles – which is why they should always be prescribed by your doctor who can then closely monitor how you are responding to the medication.

Here's an overview of Diabetes and Statins
Diabetes and statins have a complex relationship and are the focus of intense patient and healthcare debate. Statins are cholesterol-lowering drugs.

Statins are used in diabetes care due to the knowledge that people with diabetes face a greater likelihood of heart attack and stroke.

When used alongside good blood glucose control and other medication, the case for statins argues that they cut cholesterol levels and lower the risk of a cardiovascular event.

Type 2 diabetes in particular is certainly a disease of the circulatory system, and this argument has some weight.

How can I lower my risk of cardiovascular problems without taking statins?
There are many ways to lower your risk of stroke and cholesterol levels. These include stopping smoking and controlling your blood pressure. Diet and exercise can help to lower raised blood pressure, and a healthy lifestyle can cut cholesterol levels. However, some doctors prescribe statins to help reduce cholesterol levels.

What do statins do for people with diabetes?
Statins slow the action of the liver in manufacturing cholesterol, causing blood cholesterol levels to fall.

Do statins work for people with diabetes?
Statins definitely lower cholesterol, and major studies have shown that the risk of heart attack and stroke plummets amongst people with diabetes taking statins. Results indicate that statins can prevent cardiovascular disease by reducing heart attack and stroke risks.

What are the side effects of statins?
Statins are usually well-tolerated by people with diabetes. Side effects can include:

• Headaches

• Affect on liver function

• Stomach problems such as abdominal pain, constipation, flatulence, diarrhoea and vomiting

• Rashes

• Disorder of the muscles (myopathy)

Shouldn’t all people with diabetes therefore take statins?

Statins are the subject of current and ongoing healthcare debate when it comes to diabetes patients. Further research is in progress to make the wider use of statins in diabetes care more clear.

Often, people under 40 may not benefit from taking a statin.

A statin is also just one part of diabetes care and shouldn’t be used instead of good diet, exercise, smoking and excess drinking avoidance.

Source: diabetes.co.uk

Link Between Diabetes and Greater Damage From Strokes Revealed

One reason why people with diabetes can suffer more damage during strokes has been discovered by US scientists. The study on rats, published in Nature Medicine, found a protein which increased bleeding when blood sugar levels are high.

Elevated sugar levels have been linked to at least one in ten strokes. There are two main types, 80% are caused by blood clots in the brain (ischemic stroke) and 20% when blood vessels bleed into the brain (hemorrhagic stroke).

More than half of people with hemorrhagic strokes have high levels of sugar in the blood. The hemorrhages also seem to be more severe, forming over a larger area of the brain, causing more damage and increasing the risk of death.

Linking sugar and stroke

Scientists at the Joslin Diabetes Centre injected blood into the brains of rats with and without diabetes. The bleeding was ten times greater in those with diabetes than in healthy rats.

The group then studied the impact of a protein, plasma kallikrein, which had already been linked to sight problems in diabetics. The researchers found that a combination of high blood sugar and plasma kallikrein resulted in increased bleeding. They believe plasma kallikrein slows clotting when there is lots of sugar in the blood, although the exact mechanism remains unclear.

Dr Edward Feener, who led the study, said: "Given the prevalence of strokes and the damage they inflict, these findings are exciting because they suggest the possibility that rapid control of blood sugar levels may provide an opportunity to reduce intracerebral hemorrhage, which is a clinical situation that has very limited treatment options. This work could have broad implications since about half of patients with acute hemorrhagic stroke have hyperglycemia, whether or not that have pre-existing diabetes."

Dr Sharlin Ahmed, research liaison officer at The Stroke Association, said: "Diabetes is known to increase a person's risk of stroke, and research has shown that strokes caused by a bleed in the brain are more severe in people with diabetes as a result of poorly controlled blood sugar levels. Controlling glucose levels is vital if you have diabetes. This research not only provides further evidence that glucose control can reduce your risk of stroke, but it also suggests that it could reduce the severity of a stroke caused by a bleed in the brain. However, it is very early days and much more research needs to be carried out before human trials are undertaken."

Dr Iain Frame, director of research at Diabetes UK, said: "This early research has made an interesting discovery into how high blood glucose levels interact with certain chemicals in the blood, and with the damage caused by stroke. As the authors admit, however, there are limitations in the animal model they used so their results do not reflect what happens to the human brain when it hemorrhages. Much more research is needed to test how we might be able to use this knowledge to limit this stroke damage and that will prove to be the big test as to whether this study will lead to any benefits for people with high glucose levels who have a stroke."

Courtesy bbc.co.uk

Effectiveness Of Statins Is Called Into Question

As the world's most-prescribed class of medications, statins indisputably qualify for the commercial distinction of "blockbuster." At the zenith of their profitability, these medications raked in $26.2 billion a year for their manufacturers.

But in recent months the drugs' touted medical reputation has come under tough scrutiny.

Statins were initially approved by the US Food and Drug Administration for the prevention of repeat heart attacks and strokes in patients with high cholesterol who had already had a heart attack. And used for that purpose — called "secondary prevention" — the drugs are powerful and effective medications, driving down patients' risk of another heart attack or stroke by lowering their levels of LDL (or "bad") cholesterol.

Then physicians came to believe statins could also reduce the risk of a first heart attack in people who have high LDL cholesterol but are nonetheless healthy. This use of statins — called "primary prevention" — has driven the growth in the market for statins over the last decade.

Today, a majority of people who use statins are doing so for primary prevention of heart attacks and strokes. It is this use of statins that has come under recent attack.

"There's a conspiracy of false hope," says Harvard Medical School's Dr. John Abramson, who has cowritten several critiques of statins' rise, including one published in June in the Archives of Internal Medicine. "The public wants an easy way to prevent heart disease, doctors want to reduce their patients' risk of heart disease and drug companies want to maximize the number of people taking their pills to boost their sales and profits."

Heart patients and their physicians are not the only ones to pin their hopes on statins. The drug companies that brought statins to the market have explored the medications' benefits in prevention or treatment of such conditions as Alzheimer's disease, rheumatoid arthritis, prostate and breast cancer, kidney disease, macular degeneration and diabetic neuropathy. Although clear proof that statins could forestall or treat any of these diseases might bring in millions of new, paying customers, results have largely been mixed, inconclusive or disappointing.

In an ideal world, debate over the clinical virtues or vices of a drug would be long settled by the time the medication saw a meteoric rise in use. But in a healthcare system that relies on commercial incentives to spur drug development, prescription medications are a product like any other.

The FDA assesses drugs' safety and effectiveness for specific use; but its judgments are based on preliminary data, most of it generated by a drug company seeking approval for its product. Once the agency approves a drug for marketing, the company that makes it will move quickly and aggressively to expand the universe of patients taking its product.

Sometimes, by the time the deliberate pace of medical research and debate suggests that a drug is not all it's been cracked up to be, it's already become a bestseller. Statins, say some who study the relationship between medicine and the drug industry, seem to fit that pattern.

Statins appear to drive down the risk of heart attack or stroke by lowering the levels of fatty deposits circulating in the bloodstream. Research suggests that the drugs dampen inflammatory processes that can prompt deposits of plaque to break away from blood vessel walls and cause sudden blockages of arteries leading to the heart or brain.

And yet, the relationship between cholesterol-lowering and heart disease is not perfectly understood, and the precise role of inflammation in heart disease is also uncertain.

Statins certainly decrease rates of heart attack in people who have clear signs of cardiovascular disease, but it's not so clear they work that way in people who are healthy. In spite of that uncertainty, statins' use for primary prevention has skyrocketed.

That's the issue in the latest round of debate, which spilled onto the pages of the Archives of Internal Medicine in late June: whether statins prevent, safely and at a reasonable cost, the development of cardiovascular disease in people who are still healthy but are considered to be at high risk of a heart attack or stroke.

In the first of three studies published in the Archives last month, medical researchers found that, contrary to widely held belief, statins do not drive down death rates among those who take them to prevent a first heart attack.

A second article cast significant doubt on the influential findings of a 2006 study, called JUPITER, that has driven the expansion of statins' use by healthy people with elevated blood levels of C-reactive protein, a measure of inflammation. A third article suggested potential ethical, clinical and financial conflicts of interest at work in the execution of the JUPITER study and concluded the widely hailed trial was "flawed" and raises "troubling questions concerning the role of commercial sponsors."

"Tens of billions of dollars of revenue for the sponsor over the patent life of the drug were at stake in the JUPITER trial, as well as potentially millions of dollars in royalties for the principal investigator," wrote Dr. Lee Green of the University of Michigan Medical School in an editorial accompanying the trio of studies. "Doubtless, both sponsor and investigative team believe they made their design decisions for the right reasons," Green added. "But social psychology research provides abundant evidence that we human beings both respond strongly to self-interest incentives and firmly believe that we do not."

Statins still have ardent admirers, including cardiologist Steven Nissen of the Cleveland Clinic in Ohio. For many patients on a clear collision course with heart disease but not there yet, he said, statins make a difference. And even though recent studies question whether statins reduce heart attack deaths, Nissen added, many patients' lives are clearly improved by pushing a heart attack further into the future.

The stakes of this debate are big and continuing to grow (see related story, " Pinning down the side effects of statins"). As many as three-quarters of patients currently taking statins haven't yet had a stroke or heart attack; they have diabetes or high LDL cholesterol, conditions widely thought to put them at high risk of having one.

Those patients largely joined the ranks of statin consumers after 2001, when the US National Heart, Blood and Lung Institute adopted guidelines on the treatment of patients with high cholesterol.

The guidelines, updated again in 2004, suggested that as many as 36 million Americans should take statins — essentially tripling overnight the potential American market for the drugs. Of the nine experts involved in drafting the cholesterol treatment guidelines, the National Institutes of Health later acknowledged that eight had substantial financial ties to statin makers — links that may have predisposed them to view evidence of statins' benefit in its most positive light.

Said Abramson, the author of "Overdosed America: The Broken Promise of American Medicine": The best way to drive down the risk of developing cardiovascular disease in the first place is to exercise regularly, not smoke, drink in moderation and eat a healthy Mediterranean-style diet. But, he added, "this message gets drowned out by the commercial interests" of pharmaceutical companies who stand to benefit from increased sales.

Courtesy: Melissa Healy/LA Times

Diabetes Diet Cuts Heart Attack Risk in Half

Thе're no harm in repeating this ad nauseum that even though incidence οf diabetes hаѕ doubled over thе past 10 years, many people remain unaware thаt thеу hаνе become victim tο thіѕ ѕіlеnt killer disease. Millions οf people аrе pre-diabetic, indicating a failing metabolism that wіll lead tο full diabetes, typically іn 6 months tο 2 years time.

Surprisingly, thе diagnosis οf diabetes doesn’t hаνе thе same impact οn patients аѕ οthеr potentially lethal diseases, due tο thе subtle manifestation οf symptoms before thе disease progresses fully. Bесаυѕе οf thіѕ, people аrе less lіkеlу tο take diabetes seriously, placing thеm аt high risk fοr heart disease аnd a host οf debilitating diabetic complications.

Diabetes Doubles thе Risk οf Heart Attack аnd Stroke

I will never tire of pointing out that innumerable studies have found thаt diabetes doubles thе risk οf developing life-threatening events such аѕ a heart attack οr stroke. Type II diabetes іѕ largely a disease caused bу poor lifestyle choices аnd іѕ perpetuated bу a diet οf processed junk foods that leads tο complete metabolic dysfunction.

But the good news is that diabetes саn bе controlled bу following a strict meal рlаn that drastically limits high carbohydrate foods аnd sugary drinks. Many people hаνе bееn аblе tο minimize аnd resolve blood sugar surges аnd neuropathic complications bу eliminating specific foods that сrеаtе metabolic imbalance, аnd сυt thеіr risk οf a heart attack іn half.

Carbs Count, Sο Count Thеm
Thе mοѕt іmрοrtаnt thing tο understand whеn working tο prevent οr treat type II diabetes іѕ thаt a low-fаt, high-carb diet іѕ based οn аn ancient understanding οf thе disease аnd wіll promote disease progression. Thе οnlу way tο take charge οf diabetes іѕ tο track аnd monitor еνеrу morsel οf food уου eat, аnd keep track οf thе carbohydrate count.

Carbs, regardless οf thе dietary source, cause blood sugar tο rise аnd insulin resistance tο develop. Once thіѕ metabolic imbalance bеgіnѕ, thе οnlу way tο keep іt οn track іѕ tο severely limit carbohydrate intake. Fats аnd protein hаνе a limited effect οn blood sugar аnd actually hеlр tο flatten blood sugar spikes.

Target Less Thаn 100 Grams οf Carbohydrates Each Day
Many people eat more thаn 100 grams οf carbohydrates each meal, causing wild swings іn post meal blood sugars whісh hаνе bееn shown tο lead tο metabolic dysfunction, diabetes аnd serious complications. Limit carbs frοm аll sources, including vegetables, tο nο more thаn 30 grams each meal. (Yου’ll need tο υѕе nutritional tracking software tο calculate carb counts.)

Weigh аnd measure everything аnd record іt before уου eat. Bе ассυrаtе, аѕ small deviations саn сrеаtе bіg blood sugar swings. Yου’ll find thаt tο hit уουr target carbs fοr each meal, thеrе’s nο room fοr junk foods, breads, pasta, sugared drinks, аnd even salad dressing whісh аrе pumped full οf sugar.

Mаkе fresh vegetables thе core οf each meal аnd compliment wіth solid protein аnd fаt sources frοm meats, nuts, seeds аnd legumes.

Check Blood Sugar Aftеr Each Meal

Thе οnlу trυе way tο know іf уου саn tolerate more carbs іѕ tο test уουr blood sugar wіth аn inexpensive meter. Check уουr reading 1 аnd 2 hours аftеr eating, аѕ thіѕ іѕ whеn thе highest blood sugar readings wіll bе recorded. Mаkе sure thаt уουr 1 hour reading іѕ nο higher thаn 140 mg/dl, аnd thе 2 hour reading іѕ below 120 mg/dl.

Readings above thеѕе levels indicate metabolic instability, аnd thе need tο lower уουr carbohydrate intake. Blood sugar readings above 140 mg/dl аrе associated a doubling οf risk οf heart attack аnd dаngеrουѕ complications frοm kidney disease, blindness аnd nerve dаmаgе. 

Monitor уουr blood sugar аftеr еνеrу meal, аnd soon уου’ll know exactly whісh foods cause thе lаrgеѕt swings аnd mυѕt bе avoided.

Diabetes cases wіll continue tο double еνеrу decade, jeopardizing thе lives οf millions, unless people аrе educated tο take control οf thеіr diet. Thе disease іѕ іn уουr control, аnd οnlу уου саn determine hοw іt progresses.

Many people hаνе shown thаt thеу саn prevent аnd even treat diabetes bу incorporating аn ultra-low carb diet аnd monitoring blood sugar levels carefully аftеr meals. Cυt уουr risk οf a heart attack аnd diabetic complications bу taking charge οf уουr diet аnd lifestyle.

Thank you Barry Lee

Recommended Blood Pressure Level Differs For Heart Patients With Diabetes

The best blood pressure range for patients with diabetes and heart disease appears to be slightly higher than what is recommended for healthy adults, according to a study. Blood pressure greater than 140 is still associated with a nearly 50 percent increase in cardiovascular risk in these patients.

In fact, the blood pressure range considered normal -- less than 120 systolic and less than 80 diastolic -- may actually be risky for those with a combined diagnosis of diabetes and coronary artery disease, report University of Florida researchers from the International Verapamil SR-Trandolapril study, known as INVEST.

According to Rhonda Cooper-DeHoff, Pharm D, an associate professor of pharmacy and medicine at UF, optimum systolic blood pressure levels should be between 130 and 140 for patients coping with the diabetes-heart disease combination.

Efforts to reduce systolic blood pressure to below 130 did not offer any additional benefit to patients with diabetes and coronary artery disease, compared with reduction of systolic blood pressure to between 130 and less than 140.

"Sustained blood pressure lower than 120 is considered optimal for healthy people," Cooper-DeHoff said. "But, our data show that for these patients with diabetes, the range may actually cause an increased risk for heart attack, stroke, and death."

As many as two out of three adults with diabetes have high blood pressure. Blood pressure greater than 140 is still associated with a nearly 50 percent increase in cardiovascular risk in these patients.

"While lowering blood pressure to less than 140 is very important, based on our data and data recently published by others, it is now clear that in patients with diabetes, it is not necessary, and may be harmful to lower blood pressure too much," Cooper-DeHoff said.

In addition, the study for the first time reveals that this group of patients had an increased risk for death when their blood pressure was controlled to lower than 115 systolic -- the range recommended as normal by the American Heart Association.

The findings in the Journal of American Medical Association formalize a report Cooper-DeHoff made at the American College of Cardiology's 59th annual scientific session earlier this spring.

Heart disease or stroke is the top cause of death for people with diabetes, affecting more than 60 percent of patients, according to the AHA. High blood pressure, common in diabetes, doubles the risk of cardiovascular disease.

The INVEST study is the first to evaluate the effects of blood pressure-lowering in diabetic patients diagnosed with coronary artery disease. Researchers analyzed data collected from 6,400 patients from fall 1997 to spring 2003. The patients, who were 50 or older, were recruited from more than 850 sites in 14 countries.

The researchers further consulted the national death index for US-enrolled patients for an additional five years to compare death rates of patients based on their blood pressure category ranging from tightly controlled to non-controlled hypertension.

Journal of the American Medical Association, July 10, 2010

Diabetes Is Responsible For Many Heart Disease Deaths

Don't take diabetes lightly. More than one in 10 heart disease deaths may be attributable to diabetes. In fact, my friend Shiv Harsh, MD, says most heart specialists like him equate diabetes with onset of heart disease, as it were.

In a meta-analysis of more than 100 studies, diabetes was associated with a twofold increased risk of the disease and was estimated to be accountable for 11% of vascular deaths, according to Nadeem Sarwar, MD, of the University of Cambridge in England, and colleagues.

They reported their findings online in The Lancet and will present them during an oral session at the American Diabetes Association meeting.

“In this decade, about 10% of vascular deaths in populations in developed countries have been attributable to diabetes in adults, corresponding to an estimated 325,000 deaths per year in high-income countries alone,” Sarwar and colleagues wrote.

“This burden will increase if the incidence of diabetes continues to rise, even if rates of vascular disease continue to fall because of decreases in smoking, improvements in treatment, or other reasons,” they added.

There have been uncertainties about the magnitude of associations between heart disease risk and stroke, and diabetes and fasting glucose concentration.

So to quantify those associations for a wide range of circumstances, the researchers conducted a meta-analysis of individual risk factors in patients without vascular disease from studies in the Emerging Risk Factors Collaboration.

They included 698,782 patients in 102 prospective studies. The mean age was 52 and 43% were women, with the majority in Europe, North America, and Australia, and the remainder in Japan or the Caribbean.

A total of 7% of patients reported a history of diabetes at baseline.

Over the study periods, there were 52,765 nonfatal or fatal vascular outcomes.

The researchers found that patients with diabetes had around a twofold increased risk of heart disease, ischemic stroke, and other vascular deaths:

* Coronary heart disease: HR 2.0, 95% CI 1.83 to 2.19
* Ischemic stroke: HR 2.27, 95% CI 1.95 to 2.65
* Hemorrhagic stroke: HR 1.56, 95% CI 1.19 to 2.05
* Unclassified stroke: HR 1.84, 95% CI 1.59 to 2.13
* Other vascular deaths: HR 1.73, 95% CI 1.51 to 1.98

The researchers said that risk was about a third higher for fatal than nonfatal myocardial infarction, “perhaps suggestive of more severe forms of coronary lesions in people with diabetes than those without, differential response of the myocardium to ischemia, or possibly in part, differential coding of deaths from coronary heart disease.”

Risk of heart disease among diabetics was higher in women than in men, in patients ages 40 to 59 than those 70 and up, in nonsmokers than in smokers, and in those with below-average systolic blood pressure.

Risk of stroke was higher in women, the same younger age group, and in those with above average body mass index (BMI).

These findings, the researchers said, warrant further study.

Also, at an adult population-wide prevalence of 10%, diabetes was estimated to account for 11% of vascular deaths, they added.

Yet only moderate associations were found between impaired fasting glucose and risk of heart disease and stroke.

Fasting blood glucose concentration was non-linearly related to vascular risk, with no significant associations between 3.90 mmol/L and 5.59 mmol/L.

But risk of heart disease increased with increasing plasma glucose concentrations:

* 5.60 to 6.09 mmol/L: HR 1.11, 95% CI 1.04 to 1.18
* 6.10 to 6.99 mmol/L: HR 1.17, 95% CI 1.08 to 1.26

The researchers added that risk was “substantially higher” among those with concentrations of 7 mmol/L or higher.

The study was limited in that it may not be generalizable to patients in low- or middle-income countries. But that does not mean that the findings can be dismissed as a problem faced by diabetics in developed countries. In countries like India too evidence is emerging that diabetics face more risk of heart disease than non-diabetics.

In an accompanying commentary, Hertzel C. Gerstein, MD, of McMaster University in Hamilton, Ontario, said it remains unknown whether the spectrum of dysglycemia is causally related to cardiovascular outcomes.

Trials of glucose-lowering therapies have shown a modest reduction in myocardial infarction, but “the size of the effect strongly suggests that glucose is not the only player,” he wrote. Others could include fatty acid and lipoprotein metabolism, visceral fat deposition, hepatic function, and renin-angiotensin, among others.

“Any or all of these factors (and others) might promote cardiovascular disease through various known and unknown mechanisms,” Gerstein wrote. “Large, long-term clinical trials of insulin-replacement therapy, incretins, and other approaches targeting one or more of these abnormalities … are certain to shed more light on the link between dysglycemia and serious outcomes.”

 

Thank you Kristina Fiore/MedPage Today

Diabetes Increases Risk Of Abnormal Heart Rhythm

People with diabetes are at increased risk of a common type of abnormal heart rhythm known as atrial fibrillation, new research shows.

This risk gets worse the longer a person has been taking medications for diabetes, while poor blood sugar control also exacerbates risk, Dr Sascha Dublin of the Group Health Research Institute in Seattle and her colleagues found.

Atrial fibrillation is not in and of itself deadly, Dublin noted, but it does increase a person's risk of stroke and heart failure.

Studies examining the relationship between diabetes and atrial fibrillation have yielded mixed results, and often didn't take obesity into account. This is important, Dublin noted, because obesity increases both diabetes risk and atrial fibrillation risk. "We felt that the literature really was in a state of uncertainty," Dublin said.

In the current study, Dublin and her team looked at data from Group Health, a large health care delivery system, on 1,410 people diagnosed with atrial fibrillation and 2,203 people without the abnormal heart rhythm. Eighteen percent of the people with atrial fibrillation were taking medications for diabetes, compared to 14 percent of the controls. This translated into a 40 percent increased risk of atrial fibrillation for the treated diabetics.

And the more severe a person's diabetes was, the greater their risk of atrial fibrillation.

To gauge diabetes severity, the researchers used two measurements: average hemoglobin A1C levels, a standard indicator of blood sugar control over many years; and the amount of time a person had been on medicines for diabetes.

Atrial fibrillation risk rose as people's blood sugar control worsened, the researchers found. While the risk was only about 6 percent greater for people with A1C levels of 7 or less, indicating good long-term blood sugar control, risk was about 50 percent higher for people with A1C levels between 7 and 9, and nearly doubled for people with levels above 9.

Similarly, risk of the abnormal heart rhythm increased with diabetes duration; for every additional year a person had been taking diabetes medications, their risk of atrial fibrillation increased by 3 percent.

Doctors who treat diabetic patients should be aware of their increased atrial fibrillation risk, Dublin said. She pointed out that the condition can be treated effectively, for example with blood-thinning drugs to reduce stroke risk.

And for patients whose symptoms are interfering with their quality of life, for example making them short of breath with exertion, "we can make them feel a lot better by slowing their heart down with commonly used and safe drugs," she added.

SOURCE: Journal of General Internal Medicine, online April 20, 2010.