This site complies with the HONcode standard for trustworthy health information:
verify here.

Rewarding for
you and us
Defeat Diabetes Foundation

Defeat Diabetes
Foundation
150 153rd Ave,
Suite 300
Madeira Beach, FL 33708

Tighter Control Reduces Heart Disease Risk by 17%

Posted: Wednesday, June 03, 2009

The study found extra benefits for those who kept the A1c levels closer to the 4% to 5% mark that is common for healthy people. As well as the reduction in heart attacks, there was a 15% fall in heart disease when blood sugar levels were kept to 6.6% on average.

People with Type 2 diabetes tend to have a glucose level above average despite the medication they are given. Previous studies have been inconclusive, leaving diabetics and their doctors unsure as to whether maintaining lower blood sugar levels actually benefited the patients.

The Cambridge University study of 33,000 people found getting it closer to the level for healthy people could cut the risk of heart attacks by 17% but warns the steps the researchers recommend in The Lancet will not be appropriate for everyone.

For elderly and frail people with diabetes there is a risk that if their blood sugar levels are brought too low, they can become dizzy and light-headed and, in the worst cases, fall into a coma.

The Cambridge team decided to review five of the major research projects carried out into this issue because expert opinion remained divided over the benefits to tighter sugar control.

The current guidance in the US for the 25m with the disease is to keep blood sugar levels at about the 7% mark. But the study found extra benefits for those who kept the levels closer to the 4 to 5% mark that is common for healthy people. As well as the reduction in heart attacks, there was a 15% fall in heart disease when blood sugar levels were kept to 6.6% on average.

The researchers said the findings would mean that for every 200 people treated for five years, three lives would be saved from heart attacks.

The A1c was used to measure blood sugar concentrations. In healthy individuals A1c levels average between 4 and 5%, but they often exceed 6.5% in diabetics. The pooled data showed patients on standard treatment maintained an average A1c level of 7.5%. Those who underwent intensive treatment reduced their levels to 6.5%.

Among patients taking part in the trials there were 1,497 heart attacks; 2,318 cases of heart disease; and 1,227 strokes. Intensive treatment led to 17% fewer heart attacks and a 15% reduced risk of heart disease compared with standard treatment.

Dr. Kausik Ray, the lead researcher, said, "Previous studies have been inconclusive, leaving diabetics and their doctors unsure as to whether maintaining lower blood sugar levels actually benefited the patients…. Although additional research needs to be conducted, our findings provide insight into the importance of improving glucose levels. However, this has to be done through lifestyle changes as well as medication."

Ray said the meta-analysis shows the importance of large numbers when assessing risk and benefit. He suspects that these earlier studies, such as ADVANCE and VADT, were underpowered and didn't have sufficient follow-up to show an impact on cardiovascular events. The study also showed that glucose control is slightly less effective than blood-pressure and cholesterol reductions for preventing cardiovascular events and that clinicians should first target hypertension and elevated LDL cholesterol and then go after elevated A1c levels, he said.

"Diabetics, as we know, die mostly of vascular disease, and they die about seven years earlier than their nondiabetic counterparts, even though we've made strides in terms of improving outcomes with better blood-pressure control and the use of statins for LDL reduction," said Ray. "There is still residual risk, and this is a further method to reduce that residual risk. If you do all these things together, we know that this is beneficial."

In terms of adverse effects, patients treated with intensive glucose lowering gained more weight, 5.5 pounds, on average, and had almost twice as many severe hypoglycemic events, compared with conventional treatment.

For clinicians, Ray said, the study reinforces the recommendations of the American Diabetes Association, American Heart Association, and American College of Cardiology, which state that clinicians should aim to get A1c levels to less than 7.0%. Like these organizations, Ray stressed that treatment should be individualized, however, and agents that avoid weight gain and hypoglycemia should be used.

In his editorial, Mazzone echoed a similar sentiment, noting that the 7% target can be adjusted for patients with lower risks associated with hypoglycemia, such as younger patients with no CHD, and those with higher risks, such as elderly patients with heart disease. Like Ray, Mazzone noted that blood-pressure control and LDL-cholesterol reductions will provide greater benefit toward cardiovascular-disease risk, but it is "premature to conclude that glucose control has no part to play."

But Dr. Victoria King of Diabetes UK, warned tighter sugar control would not be appropriate for everyone and advises that people with diabetes should work towards keeping their blood glucose levels within the target ranges agreed with their healthcare team. "The present findings reinforce the need for diabetic patients to achieve and maintain better control of blood sugars long-term, as a means to reduce risk of heart disease."