SUNDAY, Dec. 2 (HealthDay News) -- Avandia, a drug used by millions of diabetes patients, may contribute to bone loss, according to a new study conducted in mice.

Experts fear that, over the long term, Avandia (rosiglitazone) may speed osteoporosis, the thinning of the bones that can lead to dangerous and even fatal fractures.

The findings appear in the Dec. 2 online issue of Nature Medicine.

"Our study suggests that long-term rosiglitazone usage in the treatment of type II diabetes may cause osteoporosis due to both increased bone resorption and decreased bone formation," said study senior author Ron Evans, a professor at the Salk Institute for Biological Studies in La Jolla, Calif. "Because Avandia is effective in controlling glucose and restoring the body's sensitivity to insulin, we do not recommend that people stop their treatment. You must balance the benefits against the complications."

"Anyone who is already at risk for osteoporotic fractures should consider an alternative anti-diabetic drug," added Paul Brandt, an associate professor of neuroscience and experimental therapeutics at Texas A&M Health Science Center College of Medicine, in College Station. "There are many alternatives, " he said.

"It may [also] be possible to blunt some of Avandia's effects with anti-osteoporosis drugs such as bisphosphonates, raloxifene, vitamin D and calcium," Brandt added.

Earlier this year, Avandia and four other diabetes drugs from the same class were given a "black box" warning by the U.S. Food and Drug Administration. That warning advises users of an increased risk of heart failure while on the drug.

The black box message is the FDA's strongest label warning.

With an estimated 3.5 million or more U.S. patients taking Avandia, the public health impact from the point of view of both heart failure and bone degradation could be substantial, experts say.

Avandia affects a key cellular protein called the peroxisome proliferator-activated receptor (PPAR-gamma). In their study, the California team discovered that, in mice, activating this receptor also stimulates the production of osteoclasts, cells whose key function is to degrade bone.

Proper bone health is maintained by a balance between osteoclasts and osteoblasts, the cells that build bone up.

If either side is out of whack, so to speak, bones become thinner, more fragile and prone to fracture.

The current results are particularly disturbing in light of prior studies, the experts said.

"It was previously known that Avandia mediates bone loss by inhibiting bone formation," Evans explained. "Our work identified an additional mechanism, in which Avandia promotes bone resorption. These are the two parts of the checks-and-balance system that maintains bone in good shape. The drug weakens both sides of the balance mechanism, leading to an increased risk for osteoporosis."

"Previous research showed that Avandia reduced osteoblasts," Brandt added. "Combine the two, and you're going to get thinning of the bone."

More information

For more on diabetes drugs, visit the U.S. Food and Drug Administration.

THURSDAY, Nov. 15 (HealthDay News) -- Black children with diabetes face a death rate twice as high as that for white children, new U.S. government research shows.

While this racial disparity has been evident for more than two decades, the trend has been accelerating among children ages 1 to 19, according to the study in the Nov. 16 issue of the Morbidity and Mortality Weekly Report, published by the U.S. Centers for Disease Control and Prevention.

"Although the numbers are small, in absolute terms, these deaths are still preventable, which is why it is important to examine those disparities and work toward eliminating them," said CDC epidemiologist Dr. Laura L. Polakowski, who co-authored the report.

Looking at death certificates from 1979 to 2004, the researchers found that between 2003 and 2004, there were 89 deaths among U.S. children and teens from diabetes. During that time, the annual diabetes death rate for black children and teens was more than double that for white children.

From 2003 to 2004, the diabetes death rate per million for children and teens was 2.46 for blacks and 0.91 for whites, the report found.

In addition, the death rate among blacks has been increasing since 1998, while for whites it decreased significantly from 1979 to 1994, and then leveled off from 1994 to 2004, Polakowski's team found.

A complex interplay of factors seems to be driving the disparity, Polakowski said. "Possible explanations could be differences in access to or use of health-care services, or differences in quality of diseases education and care," she said.

Polakowski's group did not distinguish between juvenile diabetes, commonly called type 1 diabetes, and adult onset diabetes, often called type 2 diabetes. However, most diabetes deaths among children are caused by short-term complications from type 1 diabetes, Polakowski said. "We know we see these deaths with type 1 diabetes, we don't know if we see them with type 2 diabetes at this point," she said.

Many of these deaths are due to acute complications such as diabetic ketoacidosis, in which insulin levels are too low. If untreated, it leads to diabetic coma and eventually death, Polakowski said.

"These complications are readily recognizable in children and don't require a great deal of technology to treat them," Polakowski said. "The rate of death among black children can be lower, because there is a lower rate among white children," she said.

Type 1 diabetes is typically diagnosed in children and young adults and results when the body does not produce insulin, a hormone that converts blood sugar to energy for the body's cells. With type 2 diabetes -- the most common form of the disease -- either the body doesn't produce enough insulin or cells ignore the insulin, according to the American Diabetes Association. The obesity epidemic plaguing American children and adults is believed responsible for much of the explosion in type 2 diabetes cases.

One expert agrees that the pediatric deaths detailed in the new CDC report are preventable.

"I am not surprised that there would be a disparity," said Dr. Larry Deeb, past president for medicine and science at the American Diabetes Association. "That just reflects America -- doesn't it?"

All these deaths are from diabetic ketoacidosis, Deeb said. "That's what kills children with diabetes, and most of these deaths are preventable," he said.

Deeb thinks the racial disparity in diabetes deaths among children results from too many black children not having easy access to health care. With improved access and better diabetes education, "we can eliminate the disparity," he said.

More information

For more on diabetes, visit the American Diabetes Association  .

(HealthDay News) - Diabetics are prone to foot problems that can be serious enough to require amputation.

Good hygiene and regular inspection of the feet can help catch potential problems early.

Here are suggestions for diabetics on how to care for the feet and prevent injury, courtesy of the U.S. National Diabetes Information Clearinghouse:

• Thoroughly wash your feet each day in warm -- not hot -- water. Make sure you dry them completely after washing.
• Inspect your feet every day, looking for blisters, calluses, cuts, sores or any signs of redness.
• For dry skin, apply lotion -- but never between the toes.
• Gently file down corns and calluses with a pumice stone after washing your feet.
• Cut your toenails regularly, and file the edges with an emery board.
• Avoid walking barefoot, make sure shoes fit well, and always wear socks or stockings with shoes.