New Hope for Diabetic Foot Ulcers

Human-cell derived wound care products promote healing even in severe cases

After nearly a decade of unsuccessful treatment for a chronic foot wound, Paul, a sixty-something patient with diabetes faced the strong possibility of amputation. As a last attempt to avoid amputation, the Oklahoman entered a clinical trial at a specialty wound care center in Oklahoma City. Within seven weeks of beginning the revolutionary treatment, the dime-sized hole in Paul's foot was completely healed.

Like Paul, the 18.2 million Americans with diabetes¹ are particularly vulnerable to the types of wounds that resist treatment. These wounds are costly, but often futile to treat. They greatly limit a patient's physical activity, regularly forcing their exit from the workforce. The longer the ulcer persists, the greater the possibility the patient will develop a serious infection that can lead to hospitalization and possible amputation.

In addition to the devastating effects these wounds have on patients, their lifestyles and their productivity, the direct and indirect economic costs of treating them is enormous. Costs for the care of ulcerated wounds in the United States have been estimated at $5,457 per year per wound care patient-amounting to a total national annual cost of $5 billion².

Despite the high cost of care, many patients with diabetes experience wounds that never heal, leading to the rapid increase in amputation rates in recent years. Dr. Douglas Sowell, the Oklahoma City podiatrist who treated Paul, says the number of amputations has grown from 50,000 in 1986 to 86,000 in 2000.

Dr. Sowell attributes the increase in amputations to the sharp rise in the number of patients with diabetes and the high rate of obesity, which leads to complications like foot ulcers. Total direct and indirect costs of lower extremity amputations have been estimated at greater than $1 billion³.

For millions of Americans facing chronic wounds and the health care system that cares for them, the groundbreaking treatment Paul received offers great promise. The process, which uses a human cell-based material to jump start the healing process, has been successful in even seemingly hopeless cases like Paul's. Equally important for patients and payers, this healing procedure can take weeks, rather than years, meaning patients can return to their lives, and payers are not faced with an open-ended and often fruitless treatment process.

Paul's Story
Suffering from diabetes for nearly 20 years, Paul faced a number of complications from the disease, including neuropathy-a profound numbness of the limbs that primarily affects the lower extremities.

This loss of feeling in the limbs, particularly the feet, contributes to the high rate of chronic wounds faced by those with diabetes. Callouses build up and often ulcerate-meaning the tissue erodes and can become infected-before the patient notices. By then, it is extremely difficult to treat the wounds effectively. An estimated 15 percent of patients with diabetes will develop a lower extremity ulcer during the course of their disease⁴.

Paul was one of those patients. About ten years after being diagnosed with diabetes, drainage and odor from the wound on his foot drew his attention for the first time-he never felt any pain associated with it. For the next eight to ten years, Paul received regular, conventional treatment in his doctor's office for the wound, but it failed to heal.

Revolutionary treatment
Wounds like Paul's are typically treated with some type of antibiotic ointment and dressed with gauze, often on a weekly basis, in a doctor's office. Usually, though, by the time a wound has been present for more than six weeks, it needs much more than frequent dressing changes and antibiotic ointment to heal completely.

The bodies of diabetic patients are so compromised in terms of blood flow that when there is a wound, it requires extraordinary measures to initiate healing. In such cases, the dermal layer-the layer of tissue below the surface skin-needs to be healthy and growing before the wound can heal completely.

Researchers and doctors understood this problem and developed a new medical technology that combines living, fast-growing human cells with a high-tech mesh to create a growth-promoting skin substitute. The cells are embedded in the mesh, where they multiply and develop many of the characteristics, including the growth factors and proteins, found in natural skin. When the mesh-which is ultimately absorbed by the body-is placed in the wound, the human cells within it activate and help both the deeper and surface layers of the patient's own skin to grow.

Clinical trials show that this treatment approach promotes healing of diabetic foot ulcers significantly faster than ulcers treated with conventional therapy alone. "It's another modality that allows us to heal wounds. It's a great addition to the arsenal of wound treatment options. Particularly for diabetic foot wounds, it's just outstanding," says Dr. Sowell.

Some human cell-derived products available for chronic wound care management the foreskin of newborns as the donor cells. The fast-growing cells in the donor skin multiply quickly, which means limited donors are needed to produce large amounts of the product. One manufacturer of a human-cell based skin substitute says one foreskin has the potential to produce six football fields of the product. The company is still using cells from foreskin donations made in 1997 in its manufacturing process.

The cells used in the production process are tested frequently throughout the process to insure the tissue is disease free. The mother of the donor and the donor skin is tested before it is used to make the product. The final product is also tested extensively before it is sent to physicians for use with patients. The mesh is shipped and stored in a frozen state, and used in patients for up to six months.

Quick healing is efficient healing
Cost comparison data is difficult to gather for wound care treatments. Wound severity, the presence or absence of infection, and the size of the wound vary greatly from patient to patient. In addition, patient compliance-adherence to limitations on bearing weight on the wound, for example-impact the outcome of any treatment.

However, says Dr. Sowell, when a patient is properly screened for appropriateness of treatment and works with the doctor to aid the healing process, the human-cell derived skin substitute can promote healing in weeks instead of many months or even years.

When patients undergo treatment for years at a time, says Dr. Sowell, the costs just keep adding up. "If you can get it all done very quickly-get them healed and get them on with their lives-that's how we demonstrate cost-effectiveness," he says.

As the incidence rate of diabetes continues to grow, efficient treatment will become increasingly important. Estimates suggest the national cost of diabetes could grow to $156 billion by 2010 (in 2002 dollars) and to $192 billion by 2020. Direct medical costs could increase from $92 billion in 2002 to $138 billion in 2020, while indirect costs from lost productivity could increase from $40 billion in 2002 to $54 billion in 2020⁵.

The actual future cost of diabetes is likely to be substantially higher than these projected amounts if the prevalence of diabetes continues to grow-especially for type 2 diabetes, which is correlated with the growing problem of obesity in the U.S.-even after controlling for changing demographic characteristics⁶.

The availability of advanced wound management technologies for non-healing chronic wounds could greatly reduce these costs in future years.

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¹ American Diabetes Association,