MONDAY, June 9 (HealthDay News) -- The medication rosiglitazone may slow the progression of eye disease in diabetes patients, according to new research from the Jules Stein Eye Institute at the University of California, Los Angeles.

Specifically, researchers found that patients who took the drug were less likely to develop proliferative diabetic retinopathy or to experience reductions in visual acuity (sharpness). But they are not recommending the drug's use until further studies are done.

In proliferative diabetic retinopathy, existing blood vessels in the retina are blocked or damaged, resulting in the formation of new, tiny blood vessels. The condition is one of the leading causes of severe vision loss among working-age Americans, and there are few effective therapies to slow its progression.

In this study, researchers compared 124 diabetes patients who took rosiglitazone and 158 diabetes patients who didn't take the drug or a similar medication. At the start of the study, 14 eyes of the people in the rosiglitazone group (6.4 percent) and 24 eyes of people in the control group (9.3 percent) had severe non-proliferative diabetic retinopathy, an earlier stage of proliferative diabetic retinopathy.

Of the patients with severe non-proliferative diabetic retinopathy, 7.7 percent of those in the rosiglitazone group and 29.2 percent of those in the control group progressed to proliferative diabetic retinopathy within one year. After three years, 19.2 percent of the rosiglitazone group and 47.4 percent of the control group had progressed to proliferative diabetic retinopathy. That works out to a 59.5 percent reduced risk for those taking the drug.

The study also found that 0.5 percent of the rosiglitazone group and 14.5 percent of the control group experienced a loss of visual acuity of at least three lines on the vision chart during an average of 2.8 years of follow-up.

The study is published in the June issue of the journal Archives of Ophthalmology.

Rosiglitazone may delay progression of retinopathy by reducing formation of new blood vessels, the researchers said.

"However, because this study does not rigorously prove that rosiglitazone either reduces the incidence of proliferative diabetic retinopathy or prevents loss of visual acuity, and because there may be adverse effects from therapy, rosiglitazone treatment of patients with diabetes specifically to reduce these ophthalmic complications is not advocated at this time," they wrote.

Rosiglitazone can cause such adverse effects as fluid build-up, abnormal liver function test, and worsening of congestive heart failure.

"Determination of the full efficacy and clinical role of rosiglitazone in the treatment of proliferative diabetic retinopathy and other angiogenic conditions awaits confirmation of risks and benefits and possibly large-scale definitive studies," the researchers concluded.

More information

The National Eye Institute has more about diabetic retinopathy.

TUESDAY, June 10 (HealthDay News) -- New research shows that black patients with diabetes tend to fare worse than white patients do, even if they see the same doctor.

In other words, the gap can't be explained by saying particular doctors tend to give substandard care. Racial disparities in diabetes care appear to be more the result of systemic issues, according to a study in the June 9 issue of the Archives of Internal Medicine.

"It wasn't so much that black patients weren't receiving care from lower-quality providers," said study author Dr. Thomas D. Sequist, a primary-care physician at Harvard Vanguard Medical Associates. "Amongst all providers, black patients received lower quality care, even if white patients went to the same doctors."

"There have been some other studies that have shown just as much as who you are predicts what kind of care you get [race, income, gender], where you get care oftentimes is just as important or more important," Sequist continued.

Sequist and his co-authors wanted to see how far down the health-care system chain disparities went. Did it extend only to the hospital level, with some hospitals caring mostly for black patients providing lower quality care? Did the breakdown occur with individual physicians? Or was the problem even broader in scope?

This study looked at 90 primary-care physicians, each caring for at least five black and at least five white adult patients with type 2 diabetes. The physicians and patients were located at 13 different outpatient sites. In all, the study involved 4,556 white adults and 2,258 black adults being cared for at Harvard Vanguard Medical Associates.

White patients were more likely to achieve control of several key indicators of diabetes control: 47 percent of whites had control of hemoglobin A1c levels (an over-time measure of blood sugar levels) versus only 39 percent of blacks; 57 percent of whites had LDL ("bad") cholesterol levels in check, compared with 45 percent of blacks; and 30 percent of whites had their blood pressure in normal zones compared with 24 percent of blacks.

Socio-demographic factors, such as patient income and insurance explained some of the difference, in the order of about 20 percent to 30 percent, Sequist said. In other words, certain types of patients tended to cluster within certain providers.

Other diseases and conditions such as obesity or heart disease explained virtually none of the difference.

"Then you're still left with this big chunk of difference, and the question is why," Sequist said.

As it turned out, medication prescription rates tended to be lower among blacks, which might account for some of the discrepancy.

But the study was unable to explain why that might be. "We get all our data from charts and electronic medical records, so we don't have details about what discussions might have happened between physicians and patients that might have led to that lower rate," Sequist said. "Was counseling less effective among African-Americans? Were there differences in their ability to afford these medications and, if so, did the case provider decide not to order them? We don't have those types of differences."

"It's difficult to elucidate what exactly is the cause," pointed out Dr. Joel Zonszein, director of the clinical diabetes center at Montefiore Medical Center and Albert Einstein College of Medicine in New York City. "It's important to be aware of these disparities, and the issue will be to find out how to reduce them."

Sequist was also the lead author on a May 2008 study in the Journal of General Internal Medicine that found that 88 percent of primary-care clinicians agree that racial disparities in health care are a problem, but only 40 percent felt the disparities existed in their own patient populations.

That means the solution needs to begin at home. Sequist is conducting a randomized trial to see if such measures as cultural-competence training, community tours so physicians will know more about disease management outside of the 20-minute office visit (for instance, exercise and diet options in the neighborhood), and performance feedbacks.

"From our organization's perspective, the solution meant that we had to implement programs that affected all of our doctors, not a program that identified 10 to 20 lower-performing physicians and do some sort of boot-camp, quality-improvement strategy," Sequist said. "Instead, we decided to try and increase awareness amongst all physicians, and try to provide tools to deliver better diabetes care to minority patients amongst all our physicians."

More information

The Agency for Healthcare Research and Quality has more on racial disparities in diabetes.

FRIDAY, June 6 (HealthDay News) -- Two studies looking at the benefits of aggressively lowering blood sugar in people with type 2 diabetes have come to significantly different conclusions: One study found a 21 percent reduced risk for kidney disease, while the other found a 22 percent increased risk of death.

However, the first study found no increased risk of death by aggressively lowering blood sugar levels. And diabetes experts noted that the increased death risk found in the second study probably owed to the fact that the participants were "high-risk patients" -- more than one-third had suffered a heart attack or stroke before the trial began and the remainder had major cardiovascular risk factors. So the findings wouldn't apply to most people with type 2 diabetes, they note.

Both studies were presented Friday at the American Diabetes Association's annual meeting in San Francisco, and will be published in the June 12 issue of the New England Journal of Medicine.

The goal of both studies was to lower blood sugar levels through the aggressive use of drug therapy. In the second study, the goal was to reach an A1C level of less than 6 percent in the intensive therapy group, while the standard group goal was between 7 percent and 7.9 percent. When the U.S.-government sponsored trial was terminated 18 months early in February, the median A1C was 6.4 percent in the intensive group, compared to 7.5 percent in the standard group. A1C is a measure of blood glucose over the previous two to three months.

In the first study, called ADVANCE (Action in Diabetes and Vascular Disease), researchers found that among those who underwent intensive blood sugar control, there was a 21 percent reduced risk of developing kidney disease.

"Intensive glucose control significantly reduces serious vascular complications in diabetes, primarily kidney disease," lead researcher Dr. Anushka Patel, director of the Cardiovascular Division at the George Institute for International Health in Sydney, Australia, said during a teleconference Friday.

"There were no clear effects on macrovascular complications such as heart attack or stroke," Patel said. "Most importantly, using the strategy we employed for intensive glucose control, there was no increased risk of death."

In the study, 11,140 high-risk patients with type 2 diabetes either underwent intensive blood sugar control or standard treatment. By the end of the trial, most of the patients in the intensive care group were on several drugs, including insulin.

The ADVANCE researchers did not find any effect on cardiovascular disease between the two groups. The study also didn't find any increased risk of death for either group, unlike the second trial.

"These findings confirm what we already know -- that microvascular complications, and particularly kidney disease, is less with people whose blood sugar is intensively controlled," said Dr. Spyros Mezitis, an endocrinologist at Lenox Hill Hospital in New York City.

"This trial reassures us that we should be intensively controlling the blood sugar of patients so that we avoid microvascular complications," Mezitis added.

In the second study, called ACCORD (Action to Control Cardiovascular Risk in Diabetes), researchers found a 22 percent increased risk of death among patients receiving intensive blood sugar control, compared with those receiving standard treatment.

"In people with type 2 diabetes who are at high risk for cardiovascular disease, a therapeutic strategy that targets a blood sugar level below current recommendations increases mortality," ACCORD researcher Dr. Hertzel C. Gerstein, a professor in the Department of Medicine at McMaster University in Hamilton, Ontario, Canada, said during the teleconference.

"The reasons that people died was varied and there was no one reason that people died, and there was no clear difference in the actual cause of death in the intensive or standard group," Gerstein said. "Many analyses have been done to try to see if a reason could be found to explain why there was this mortality finding. At this point in time, none of these analyses have identified any one reason."

In the study, 10,251 patients with type 2 diabetes received intensive blood sugar control or standard treatment. During the trial, there was a 35 percent higher rate of death from cardiovascular events among patients in the intensive treatment group. However, those in the intensive care group also had a 24 percent lower risk of having a nonfatal heart attack. There was no difference between the groups in the risk for nonfatal stroke or heart failure, the researchers found.

Despite the findings of the ACCORD trial, one diabetes expert doesn't think they apply to most people with type 2 diabetes.

"Early and aggressive blood glucose control remains the optimum treatment approach for people with type 2 diabetes," said Dr. James A. Underberg, a clinical assistant professor of medicine at New York University Medical School.

Underberg said the results of the trial reflected the patient population in the study -- people with heart problems -- and not the dangers of aggressively lowering blood sugar.

"Data showing that high-risk patients are at greater risk for heart disease are not surprising, and should be considered a non-event for the average patient," Underberg said. "It's important that we don't lose sight of the benefits of lowering blood sugar, including fewer long-term microvascular complications."

"As I've always told my patients with type 2 diabetes, it's important to achieve and maintain your blood sugar goals," he said. "ACCORD hasn't changed any of that. The trial was conducted in a select patient population, which is just not reflective of the majority of the millions of Americans with type 2 diabetes."

More information

To learn more about type 2 diabetes, visit the American Diabetes Association  .