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Gender matters in plasma transfusions

Tue, 23 Jan 2007 02:27:53 GMT
By LAURAN NEERGAARD, AP Medical Writer
WASHINGTON - The plasma transfused into victims of burns, car crashes and other serious conditions soon will come almost completely from men. Make no mistake: Women need to donate blood now more than ever as blood supplies become more precarious each year.
But blood banks are beginning to separate out women's plasma — the liquid part of blood — in an effort to fight a mysterious lung injury that has become the nation's leading risk from transfusions.

Ask about blood safety and most people think of HIV or other diseases that, thanks to strict testing, actually are incredibly rare in U.S. transfusions. Today the top threat is TRALI, or "transfusion-related acute lung injury," in which transfusions trigger reactions that fill patients' lungs with fluid, leaving them gasping for air.

There are no good counts, although TRALI is thought to strike a few hundred people a year and kill roughly 10 percent of them. It's a condition doctors don't always recognize since patients who need transfusions are seriously sick to begin with, but it's starting to gain attention.

"This is a bigger problem than we were aware of," says Dr. Richard Benjamin, chief medical officer of the American Red Cross. He began studying TRALI when cases reported to his agency almost doubled in two years.

No one knows exactly what causes TRALI. But certain immune cells carried by women who have been pregnant are emerging as a chief culprit, cells called antibodies that mothers-to-be produce in reaction to their fetus' foreign father cells.

The antibodies do no harm to mother, baby or the vast majority of people who encounter them in a transfusion. To get TRALI requires what Celso Bianco of America's Blood Centers calls "a horrible coincidence" in which the transfusion recipient has white blood cells that just happen to recognize and clash with the donor's antibodies.

When blood is donated, it is separated into its major parts — oxygen-carrying red blood cells that make up most transfusions, plus platelets and plasma. Those problem antibodies seem to cluster most in plasma. Indeed, Benjamin found 60 percent of TRALI fatalities reported to the Red Cross were linked to plasma transfusions.

That's good news, because it points to an easy way to reduce TRALI.

Only about a quarter of the plasma that blood banks collect is directly transfused. The rest is used to manufacture other lifesaving blood products, such as clotting factors for hemophiliacs or infection-fighting immune globulin. So three years ago, Britain began an experiment: reserving male-donated plasma for transfusions, and separating plasma donated by women for manufacture into those other drugs. TRALI cases plummeted, researchers reported at an international blood meeting last fall.

Now U.S. blood banks are following suit. The Red Cross, which provides about half of the nation's blood supply, already has shifted to about 95 percent male-donated plasma for transfusions in a few parts of the country and is expanding the policy nationwide this year. A number of independent blood banks, which provide the other half of the nation's blood, are making the switch, too.

Altogether, the change could prevent about 150 cases of TRALI a year, and 15 deaths, estimates Dr. Patricia Kopko, medical director of BloodSource, a California blood bank that made the male-donor shift on Jan. 1.

The switch won't mean all female-donor plasma goes to drug-making; supply problems mean a little still will be needed for direct transfusions.

Nor does it completely solve TRALI. "We're fixing the biggest problem first," says Benjamin.

Here's the puzzle: If these common antibodies were TRALI's only trigger, the lung ailment would be common, too. Instead it's rare, occurring about once per 5,000 units of transfused blood products.

Something has to "prime" the lungs to be susceptible, explains Dr. Christopher Silliman, a pediatric hematologist at the University of Colorado and Denver's Bonfils Blood Center. The patient's initial disease, or some other factor such as undergoing anesthesia, appears to make the lung's lining hyperactive. Only then can antibodies — or other substances that break down in blood products as they age — infiltrate the lung and hurt it.

Also, the implicated antibodies aren't just in plasma. Smaller concentrations are in blood-clotting platelets, which are in such short supply that blood banks could never use only those from men. Blood banks are hunting other solutions, such as ways to test which donors have high antibody levels.

Only because blood is so protected today from infections can scientists tackle TRALI — and they worry that the gender focus might deter women from giving blood at a time when every donor is critical. Demand for blood is rising annually, yet only 5 percent of Americans eligible to donate do so and each year brings periodic shortages.
Women should "not get the idea that they are not needed, because they are vitally needed," Kopko stresses. "We transfuse a whole lot more red blood cells than plasma."
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EDITOR'S NOTE — Lauran Neergaard covers health and medical issues for The Associated Press.

Antidepressants may raise bone risk

Tue, 23 Jan 2007 02:28:09 GMT
By LINDSEY TANNER, AP Medical Writer
CHICAGO - The most popular pills for depression might substantially raise the risk for bone breaks in older people, a drawback that should be considered when the drugs are prescribed, Canadian researchers say.
People aged 50 and older who took antidepressants, including Zoloft, Prozac and other top-sellers, faced double the risk of broken bones during five years of follow-up, compared with those who didn't use the drugs, the study found.

Still, few of 5,008 people studied used the drugs and had fractures. While more rigorous research is needed to prove the link, the study provides the strongest evidence yet tying these drugs to fracture risks, said Dr. David Goltzman, an endocrinologist at McGill University in Montreal and one of the study authors. The study was part of ongoing osteoporosis research funded partly by the Canadian Institutes of Health Research and makers of osteoporosis drugs.

Antidepressants have been linked with low blood pressure and dizziness leading to falls, which can increase risks for broken bones, but the researchers said they found fracture risks independent of those factors.

Research in animals suggests that the pills might have a direct effect on bone cells, decreasing bone strength and size, Goltzman and colleagues said.

The results have important public health implications since millions of people worldwide use the drugs and because osteoporosis, a bone-thinning disease that can lead to broken bones, can be so debilitating for older adults, Goltzman said.

Still, the researchers said potential fracture risks should be balanced against the drugs' effectiveness at treating depression, which also can be debilitating.

Depression affects about 10 percent of U.S. adults, or nearly 30 million people, including about 7 million aged 65 and older. Depression in older adults is often missed and untreated.

"If patients need these drugs, they should not be advised against taking them because of the fracture risk. They should however be warned about the risks," Goltzman said.

The study appears in Monday's Archives of Internal Medicine.

Some previous studies found similar results but did not adequately consider other factors, the researchers said.

Dr. Gregory Asnis, director of an anxiety and depression clinic at Montefiore Medical Center in New York, said depression itself has been linked with low bone density, and it's possible the disease rather than the drugs could explain the findings. He said more rigorous research is needed.

The drugs in question are called SSRIs or selective serotonin reuptake inhibitors. These are generally the favored treatment for depression in many patients and their combined U.S. sales jumped 32 percent from 2000 to 2004, to more than $10.9 billion, the researchers said.

The study tracked 5,008 Canadians aged 50 and older for five years. They included 137 people who reported using SSRI antidepressants daily. In this smaller group, 18 people or 13.5 percent had bone fractures during the follow-up, compared with 317 people with fractures or 6.5 percent among the 4,871 who didn't take the pills.

Broken forearms, ankles, feet, hips and ribs were the most common fractures.

Amy Sousa, a spokeswoman for Prozac maker Eli Lilly and Co., said the drug's label lists osteoporosis as a potential but rare side effect. Still, she said the new study was too small to establish any proof that SSRIs might cause fractures.

Pfizer Inc., maker of Zoloft, issued a statement responding to the study and calling depression "a serious problem in the elderly that is under-diagnosed and under-treated."

"SSRIs are an important option for the treatment of depression in this population. As the authors note, the risks must be balanced against the benefits gained by the treatment of depression," Pfizer said.
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South Africa TB patients may be detained

Tue, 23 Jan 2007 02:28:46 GMT
By MARIA CHENG, AP Medical Writer
LONDON - Doctors have recommended forcibly detaining people in South Africa who refuse treatment for a drug-resistant form of tuberculosis, an extreme measure meant to keep the infected away from others to curb the spread of the disease, according to a paper published Monday in an international medical journal.
Since detecting extensively drug-resistant tuberculosis, also known as XDR-TB, in South Africa last year, health officials have called for increased measures to combat the strains, including better surveillance, diagnostics and drugs.

In their paper in the Public Library of Science Medicine journal, physicians Jerome Amir Singh, Ross Upshur and Nesri Padayatchi propose that XDR-TB patients who refuse treatment be involuntarily detained in hospitals or other health care facilities. Singh and Padayatchi are at the Centre for AIDS Programme of Research in South Africa, and Upshur is the director of the Joint Centre for Bioethics at the University of Toronto.

Ronnie Green-Thompson, an adviser to the South African Department of Health, said the idea had been discussed by health experts in South Africa and elsewhere, and was a possibility.

"Holding the patient against their will is not ideal but may have to be considered in the interest of the public," Green-Thompson said in a statement issued by the South African Department of Health. "Legal opinion and comment as well as ... the opinion of human rights groups is important.

In the 1990s, New York City health authorities authorized the forcible detention of people who rejected TB treatment, some for as long as two years, ultimately leading to a significant dip in cases. The detainees were held in Bellevue or Goldwater hospitals.

Last September, the World Health Organization announced there were 53 confirmed XDR-TB cases in South Africa, of which 52 were fatal. Most of the patients were also HIV positive. To date, more than 300 cases have been identified, and at least 30 more are picked up each month.

Though extensively drug-resistant tuberculosis exists worldwide, including in eastern Europe, Russia and the United States, Africa's high number of HIV/AIDS patients makes it particularly worrying. Not only does HIV/AIDS fuel the spread of tuberculosis, but infection with both HIV/AIDS and XDR-TB means an almost certain death. Weak African health systems lack the means to treat XDR-TB patients, for whom the only drugs that might work are much more expensive than regular TB drugs.

There are also social conditions in South Africa to foster the spread of XDR-TB, including a population of migrant laborers and an active tourism industry. In addition, South Africa routinely suspends social benefits to people when they are hospitalized, so many patients avoid treatment.

In their paper, the doctors recommend that XDR-TB patients be paid while being detained.

"This isn't a carte blanche to public health authorities to start locking people up," Upshur said. "If we ask individuals to forgo their rights, they need to be supported."

Some public health experts say South Africa and the international community haven't taken basic outbreak response steps, such as drafting an emergency plan, conducting a proper investigation and reinforcing surveillance. WHO and its partners have held a flurry of international meetings since XDR-TB in South Africa was identified, but little has changed for patients in Africa.

"The government hasn't yet done the most obvious things to shut down transmission," said Mark Harrington, executive director of the Treatment Action Group, a health advocacy group. "Starting to imprison patients is a step very far downstream from where we are now."

Green-Thompson, the South African Health Department adviser, said all measures were being considered and that early diagnosis and treatment were "of paramount importance."

Others worry that involuntarily detaining people would result in "driving patients underground," said Dr. Tido von Schoen-Angerer of Medecins Sans Frontieres, the international medical aid group.

Tuberculosis experts at the World Health Organization believe XDR-TB is as serious a threat to global health as either bird flu or SARS. But Dr. Mario Raviglione, director of WHO's Stop TB department, isn't certain involuntary confinement is warranted yet. Without proper patient data from South Africa, Raviglione says it is not known whether lack of compliance is a significant factor.

Still, he will not rule out the tactic.

"We can't put the public at risk of a disease that is almost incurable," Raviglione said.

AIDS group sues Pfizer over Viagra ads

Mon, 22 Jan 2007 22:32:30 GMT
By ANDREW BRIDGES, Associated Press Writer
WASHINGTON - An
The lawsuit, filed in Los Angeles by the AIDS Healthcare Foundation, calls Pfizer's ads for the impotence drug false and misleading. The suit echoes allegations made in an ad campaign announced by the group last month.

The nonprofit group alleges the marketing of Viagra has fostered an increase in the spread of sexually transmitted diseases. Studies have found the drug is used — illegally — in conjunction with crystal methamphetamine to form a party drug "cocktail."

While crystal meth can heighten sexual desire, it also can impair the ability to have an erection, said Michael Weinstein, president of the AIDS Healthcare Foundation. "In order to satisfy that heightened desire, you have to take Viagra," Weinstein told reporters.

Pfizer denied it promotes the recreational use of its blockbuster drug. In 2005, Pfizer had $860 million in U.S. Viagra sales, according to IMS Health Inc.

The suit, filed in Los Angeles Superior Court, seeks to halt the New York company from running ads like those that have promoted the drug's use on New Year's Eve and Super Bowl Sunday, said Tom Myers, the AIDS group's legal counsel. The ads, which included taglines like "Be this Sunday's MVP" encourage recreational use, the group alleges.

The suit also seeks to force Pfizer to undertake a public information campaign on the dangers of misusing and abusing the prescription drug. Furthermore, it seeks an unspecified amount to cover an increase in treatment costs borne by the nonprofit group, which runs free treatment clinics.

Pfizer said it and a company foundation already support AIDS prevention efforts, including a three-year, $6 million project undertaken in 2003 in nine southern states.

The advertisements in question featured younger-looking men than did earlier Viagra ads that used retired Sen. Bob Dole, then in his 70s, as a pitchman. Myers said the newer ads imply the drug is meant to enhance the sexual experience and not to treat a medical condition.

A Pfizer official warned against confusing age with the degree of impotence.

"The age of the personality that's always seen in promotional materials doesn't necessarily depict severity," said Dr. Ivan Levinson, senior medical director for Pfizer Urology and Sexual Health.

The AIDS Healthcare Foundation also wants the Food and Drug Administration to step up its oversight of Viagra ads.

An FDA spokeswoman declined to comment.

In 2004, the FDA warned Pfizer that some television ads for Viagra made it clear the drug was for sex, but failed to note it was to treat impotence. The ads also failed to provide information on its major side effects, according to the letter.

Filing of the suit came as Pfizer announced it would cut 10,000 jobs in seeking to trim its annual costs by $2 billion.
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