Newsline

• HIV Linked to Increased Risk of Blood Clots
• Report on Global AIDS Offers Dire Prognosis
• HIV Toll Heavier on U.S. Blacks; New Cases on Rise in Disadvantaged
• Researchers Say New Viral Strains Adapting Quickly
• New Treatment Guidelines for HIV Patients Suggest Drug Treatment Can Be Delayed

HIV Linked to Increased Risk of Blood Clots

People with HIV who are younger than 50 may be at an increased risk of potentially fatal blood clotting, called venous thrombosis, suggests a study published in the May issue of AIDS Patient Care and STDs (2002;16:205-209). Although the scope of the problem needs to be examined further, the study alerts physicians who treat HIV patients to the risk of these blood clots, according to lead author Dr. Peter R. Smith of Long Island College Hospital in Brooklyn, New York.

Several years ago, if an HIV-positive person had shortness of breath and other signs of lung illness, Smith explained, a doctor would have considered the possibility that the person had pneumocystis carinii pneumonia or other common HIV-related infections. Based on the results of this study, it would be a good idea to consider a pulmonary embolism -- a blood clot in the lungs -- as the source of the respiratory symptoms, he said. Venous thromboembolism occurs when a blood clot or other blockage forms in the deep veins of the legs. If the clot breaks free and travels to the lungs, it may block an artery in the lungs, causing pulmonary embolism.

According to Smith, several case reports have suggested that there may be a relationship between HIV and an increased risk of venous thromboembolism. To test this connection, Smith and his colleagues reviewed the medical records of all patients with either HIV or venous thromboembolism who had been discharged from their hospital from July 1998 through June 1999. The study included 362 patients who were HIV-positive and 244 who had venous thromboembolism.

As a group, people with HIV were not more likely to have a blood clot. The rate of venous thromboembolism was 2.8 percent among HIV-positive patients and 1.8 percent among negative ones, a statistically insignificant difference. But when the analysis was limited to people younger than 50, HIV-positive individuals were significantly more likely to have deep-vein clots, the researchers report. In fact, 22 percent of patients younger than 50 who had venous thromboembolism were also HIV-positive.

That younger HIV patients were more likely to have deep-vein clots is surprising, note the authors, since in the general population such clots tend to occur more frequently among older people. And even though younger individuals who have deep-vein thrombosis are more likely to be women than men, among the HIV-positive patients younger than 50, men were more likely to have the clots, the report indicates.

The reasons for the apparent increase in clotting risk among some people with HIV are uncertain, the investigators add. "We don't claim that it is the definitive study on the issue," said Smith. Still, he said that if physicians who treat people with HIV encounter a patient who has unexplained respiratory symptoms, "they should look for the possibility" of venous thromboembolism. (Reuters Health, 05.29.02, Merritt McKinney)

Report on Global AIDS Offers Dire Prognosis

The global AIDS epidemic is larger and more far-reaching than epidemiologists believed possible a decade ago, and it is taking an increasingly unpredictable course. In Africa, AIDS has not yet reached its saturation point, though AIDS has infected up to a third of young adults in some cities. At the same time, several of the world's biggest countries -- China, India and Indonesia -- are on the brink of outbreaks that, if not addressed soon, could dwarf the current epidemic, which affects about 40 million people worldwide.

Those are among the conclusions of a huge report on the AIDS pandemic released by the UN. The 226-page document is a distillation of many dozens of studies conducted in recent years on the changing rates of HIV in dozens of countries, regions and population groups around the world. While much of it simply adds detail to the trends previously recognized, the report as a whole reaches a new and chilling conclusion: the AIDS pandemic is the most complicated one in history, with both the forces driving it and the forces capable of quelling it in flux.

While the report notes numerous pieces of good news -- prevention campaigns in Uganda and Thailand that have cut those countries' infection rates; the tenfold rise in the number of Africans getting antiretroviral drug therapy in the past two years -- the overall conclusions are alarming.

The authors predict that in the next 20 years, 68 million people will die of AIDS if current levels of prevention and treatment do not change. Last year, about 3 million people died of AIDS around the world. "Circulating in southern Africa ... has been the hope that the epidemic may have reached its 'natural limit,' beyond which it would not grow. It has been assumed that the very high prevalence rates in some countries have reached a plateau. Unfortunately, this appears not to be the case," the report said. The report is available at www.unaids.org. (Washington Post, 07.03.02, David Brown)

HIV Toll Heavier on U.S. Blacks; New Cases on Rise in Disadvantaged

The number of new HIV/AIDS cases in the United States appears to have stabilized during the last three years, but U.S. researchers said that the impact is growing among disadvantaged populations, notably African-Americans. African-American women and men account for 75 percent of cases involving heterosexual transmission, "a hugely disproportionate total," said Ronald O. Valdisseri, a senior AIDS official at the CDC. In all, heterosexual cases rose 10 percent over the past three years to a little more than a quarter of all cases.

African-American men compose 40 percent of the infections among gay and bisexual men, according to figures from 25 states analyzed by the CDC. And in a separate study of high-risk populations in six major U.S. cities, 91 percent of HIV-infected African-Americans who are gay or bisexual did not know their status, compared with 60 percent among HIV-infected white males. Seventy percent of infected Hispanics also did not know. "That's a stunning number," Valdisseri said, adding that the problem was compounded with the finding that over half of them had not been using condoms.

The data were released at the start of the 14th International AIDS Conference in Barcelona, Spain. Peter Piot, director of the Joint UN Program on HIV/AIDS, who sat on a panel with Valdisseri, said that the new trends in the U.S. epidemic seemed to have similarities with patterns of the disease in Africa. A handful of U.S. researchers have found echoes of Africa's epidemic in poor and disenfranchised minority communities in the United States. Valdisseri, in an interview, resisted the African parallel, saying that the 25-state and six-city studies were not conclusive. But he said the increase in heterosexual transmission -- Africa's epidemic is almost completely passed through heterosexual relations -- and the disproportionate impact on African-Americans "is certainly a concern." (Boston Globe, 07.08.02, John Donnelly)

Researchers Say New Viral Strains Adapting Quickly

Mutant strains of HIV resistant to many of the newest drugs are turning up in larger numbers of newly infected gay men in San Francisco, according to a five-year study. The findings are based on a University of California-San Francisco study of genetic changes in HIV blood samples of patients known to be infected within one year of the test.

Findings of the study include:

• In 1996, only 2.5 percent of those tested for HIV were infected by a virus resistant to two different classes of drugs. That number rose to 13 percent by 2000. Resistance had developed quickly to the class of AIDS drugs called non-nucleoside reverse transcriptase inhibitors.

• The mutated viruses are being spread by patients currently under treatment, in whom the virus is evolving ways to sidestep medicines targeted against it.

Dr. Frederick Hecht, co-author of the study released early for the conference ("Time Trends in Primary HIV-1 Drug Resistance Among Recently Infected Persons," Journal of the American Medical Association, 2002; 288:169-180) said the research is important because patterns detected among the city's closely studied populations of HIV-infected men are early indicators of how the epidemic will evolve elsewhere.

It remains unclear, however, just how dangerous the trend may be. The number of patients initially infected by the drug-resistant strains remains small, and there is some evidence that mutant viruses are less lethal than their wild-type counterparts. Patients initially infected with the newer viral strains showed a higher level of disease-fighting white blood cells than those carrying the non-mutant virus. In theory, the mutant strains may be so battered by antiviral drugs that they are evolving into a less dangerous virus. Hecht cautioned, however, that the differences in blood cell counts were not large and further studies are needed to determine whether the new viruses are "less fit" to do damage. It can take 10 years for an untreated HIV infection to progress to AIDS. In the short term, a new infection by a mutant strain is more problematic to treat because patients with the new virus must start their treatment with drugs of last resort, the "salvage regimes" normally reserved for those who have failed prior treatments. (San Francisco Chronicle, 07.07.02, Sabin Russell)

New Treatment Guidelines for HIV Patients Suggest Drug Treatment Can Be Delayed

New treatment guidelines suggest symptom-free HIV patients can wait longer than previously recommended to begin taking AIDS drugs. The new guidelines appear in the July 10th issue of the Journal of the American Medical Association ("Antiretroviral Treatment for Adult HIV Infection in 2002: Updated Recommendations of the International AIDS Society-USA Panel," 2002; 288:222-235).

"The threshold for initiation of therapy has shifted to a later time in the course of HIV disease" because of increased awareness of the effectiveness of AIDS drugs and their toxic side effects, the International AIDS Society-USA panel, concluded.

The panel recommends starting drug treatment when levels of the disease-fighting CD4 count drops to between 200 and 350/cubic millimeter. The drugs may be beneficial in some patients with higher counts, but the risks in such patients generally outweigh the benefits, said the guidelines.

The International AIDS Society-USA, a nonprofit group that educates doctors involved in AIDS care, does not recommend which specific drugs should be used. But it says patients are more likely to stick with drugs taken twice daily than with those that must be taken more often.

"A few pills a day can control the virus as effectively as large handfuls did only a few years ago," said board chair Dr. Paul Volberding of the University of California-San Francisco. (Associated Press, 07.07.02, Lindsey Tanner)

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This article was provided by Body Positive. It is a part of the publication Body Positive.