TUESDAY, Aug. 22 (HealthDay News) -- There's surprisingly little scientific evidence on how best to prevent pressure ulcers (bed sores), even though they're common among people with limited mobility and cost billions of dollars a year to treat, says a Canadian study in this week's issue of the Journal of the American Medical Association.

Researchers reviewed 59 studies on preventing bed sores. The studies were conducted over the past 30 years and involved nearly 14,000 patients. Still, considering the magnitude of the problem, that's a meager number of studies for such a long period of time, the researchers said.

"Pressure ulcers are common in a variety of settings and are associated with adverse health outcomes and high treatment costs," lead author Dr. Madhuri Reddy, a geriatrician and chronic wound specialist at Women's College Hospital in Toronto.

"We found that the majority of published studies which have examined interventions to prevent pressure ulcers have been inadequate in their design and have not generated robust scientific evidence from which to develop comprehensive and unequivocal best practice guidelines," Reddy said.

Pressure ulcers range from slight skin discoloration to open sores that go all the way to the bone and frequently develop in the tail-bone area, and the hips and heels. Pressure ulcers can prolong a patient's hospital stay and be complicated by pain and infection, which can even result in death.

Sixty percent of pressure ulcers develop in patients admitted to hospital and many of the affected patients are elderly and/or have diabetes or vascular disease. Pressure ulcers can develop within three to six hours in immobile patients.

An estimated 2.5 million pressure ulcers are treated each year in acute care facilities in the United States, at a cost of about $11 billion. Elderly people in long-term care are also at risk for pressure ulcers, particularly those who are immobile, incontinent, or have dementia.

"There seems to be a huge mismatch between the billions of dollars we're spending on treating this condition, including an incredible amount of nursing time, and the relatively little effort in determining best practices for prevention," senior author Dr. Paula Rochon, a geriatrician and senior scientist at Baycrest Geriatric Health Care System, said in a prepared statement.

More information

The American Academy of Family Physicians has more about pressure ulcers.