POSITIVELY AWARE November/December 2011
IAS Conference updates from Rome
Conference Coverage
Gay couples at risk
Atlanta researchers found a high rate of HIV in gay male couples who thought both partners were HIV-negative.
“About 20%, or one in five couples, had a serodiscordant status, where one partner is negative and the other is positive,” reported lead researcher Dr. Patrick Sullivan during a late breaker presentation. In 3% [three couples], both partners were HIV-positive. Overall, one out of nine men in the study had a previously undiagnosed HIV infection.
Researchers from Atlanta’s Emory University were studying HIV testing and counseling in gay male couples as opposed to individuals. They reported looking at couples voluntary counseling and testing (CVCT), which they said has never been tested in gay men, though it is an effective intervention in South African heterosexual couples, shown to have decreased HIV transmission by 50%. All together, said Sullivan, “Couples testing and counseling reached a population of MSM [men who have sex with men] with much higher undiagnosed HIV prevalence than traditional CVCT.”
All of these men must have tested negative for HIV within the past year in order to be eligible for the study. The couples needed to have been together for at least three months; half of them were together for more than a year and half were a couple for less than 13 months. According to the team’s research abstract, “A couple’s testing service attracted men with a high frequency of undiagnosed HIV infection. Men in steady relationships may perceive less need for HIV testing, but according to our data, CVCT may be an important service to engage coupled men for HIV testing.”
The team noted that heterosexual couples in South Africa and gay male couples here share two similarities in the epidemic: there is high prevalence and committed partners are a significant driver of HIV infection. In addition, Sullivan noted that some HIV-positive people may be unlikely to disclose a positive status to partners. “In our own work, only about half of MSM report discussing their status or that of their partners before first having sex,” Sullivan said. In addition, he said, “Previous research has shown that most U.S. male couples have some agreement about whether outside partners are allowed and if so, under what conditions.”
The Emory researchers enrolled 97 couples (194 men). The majority, 77% (150 men) were black, 14% (27) were white, and 5% (9) were Latino, owing to the population served by AID Atlanta, an HIV service organization which helped the researchers enroll participants (good job, AID Atlanta). They pointed out that the results cannot be generalized to other couples. Couples in which men reported being coerced to test or having been subjected to violence were tested separately instead of together. According to the research abstract, “The necessity of exclusionary criteria should be evaluated before the service is routinely provided.” The findings are preliminary and the study continued to enroll participants.
The study results came on the heels of a Centers for Disease Control and Prevention (CDC) report on HIV testing for MSM. According to the June 3 issue of Morbidity and Mortality Weekly, in one survey of more than 7,000 men, of the 19% (1,330) of MSM who tested HIV-positive, 44% (585) were unaware of their infection. According to the report, the similar rate of infection found among MSM whether their behavior was considered high-risk or not suggests that more frequent testing of every three to six months “might be warranted among all sexually active MSM, regardless of their risk behaviors.” Currently, the recommendation is for high-risk MSM to test this often (those men with multiple or anonymous partners, methamphetamine use, who have sex in conjunction with illicit drugs, or whose partners meet these criteria).
As one caveat, both the Emory researchers and the CDC report noted that HIV testing and status may have been under- or over-reported. Interestingly, at a discussion of the news from IAS, doctors mentioned that they have patients who use HIV testing as a way to disclose their positive status to a new partner.
HIV protection for breastfed infants
Although breastfeeding by HIV-positive women is discouraged in resource-rich countries, it has been shown to protect infants from death in poorer countries. Without the protective elements in mother’s milk, these infants have a higher risk of dying from unsafe water and lack of health care or other sanitation. The question then becomes how to protect the child from becoming HIV-infected while breastfeeding.
Researchers pooled the results of five randomized studies using the HIV drug nevirapine to prevent transmission in breastfed infants. Overall, there was a 71% risk of getting HIV in infants given nevirapine. Some of the infants were given nevirapine along with zidovudine (AZT, brand name Retrovir). In the U.S., nevirapine is sold under the brand name Viramune.
Abstract WELBC03 was presented by Dr. Charles Van der Horst of the University of North Carolina, Chapel Hill. Longer duration of nevirapine use was associated with a greater reduction in risk of HIV infection. The data was taken from 5,396 mother-infant pairs in which the infant was HIV-negative at birth.
Two years ago, the World Health Organization (WHO) added the use of HIV medications to prevent mother-to-child transmission during breastfeeding, in the latest update of its treatment guidelines, based on the most current data at that time.
Does PrEP stop HIv in its tracks?
Last year, studies CAPRISA 004 and iPrEx found large decreases in the risk of HIV infection with the use of the HIV medication tenofovir, taken orally or topically (via skin). Such a strategy is called PrEP, for pre-exposure prophylaxis (prevention). At IAS, a poster presentation on the two studies suggested the possibility that tenofovir also may have stopped HIV infection while it was in progress.
In Poster MOLBPE035, CAPRISA and iPrEx researchers presented data on study participants who seroconverted to HIV. They went back to blood samples collected before these participants had been randomized in the study. Of the 20 individuals with acute pre-seroconversion HIV infection before randomization (out of 266 participants who had seroconverted), the majority (17) were in the study arms that had been given placebo instead of tenofovir. According to the poster, “Assignment to receive active topical or oral PrEP was associated with an 83% decrease in the detection of acute pre-seroconversion HIV infection at baseline: the reasons for the difference are unclear.”
Acute pre-seroconversion infection was defined as having HIV RNA detection through viral load testing along with two negative antibody rapid tests. Antibodies, the body’s response to pathogens such as HIV entering the body, take a while to develop.
According to the report, the efficacy data presented last year excluded these 20 individuals who were seroconverting before the studies began, and their data is “investigated in this report to understand how PrEP might affect the earliest stages of infection.”
Bone fractures
Certain drug side effects or medical conditions found in people with HIV are continuously receiving a lot of attention, and bone problems are among them. In an analysis from the U.S. Veterans Administration (VA), researchers once again found evidence that HIV treatment may have a negative effect on bones. One thing was clear, however: the risk of HIV therapy causing bone problems was minimal compared to traditional risk factors such as older age, diabetes, smoking, Caucasian race, and hepatitis C infection.
The researchers were especially interested in the cumulative effect of therapy on fractures—does the risk of fracture go up with a longer duration on HIV treatment? They were also particularly interested in the effect of Viread (tenofovir), which has been associated with loss of bone mineral density. Viread is also found in Truvada, Atripla, and Complera.
The VA looked at two time frames for this analysis—1988 to 1995 and 1996 to 2009, the era of HAART (highly active antiretroviral therapy). They looked at the medical records of 56,660 patients with HIV. Of these, 951 experienced a fracture of the wrist, hip, or first vertebra (in the spine) over the entire two time periods. Most of those fractures occurred in the HAART era, 572 cases in 32,439 patients.
The analysis looked at osteoporotic fractures (OF), those of bones that are weakened by osteopororsis. Of note, these fractures were inferred, not confirmed, using a record coding system that the VA has validated. Moreover, they point out that they did not actually look at bone mineral density (BMD) itself, which has been the primary concern in HIV. Decreased BMD, indicating osteoporosis, has been associated with HIV therapy and with the virus itself.
Over the entire time frame, the risk of fracture with exposure to antiretrovirals was statistically significant for Viread and boosted protease inhibitors (PIs). However, when factoring in other risk factors (such as hepatitis C) or other antivirals, that association went away. In the HAART era alone, the association with Viread use continued when looking at the drug by itself or in multivariate analysis with either traditional risk factors or traditional risk factors plus the use of other antivirals. All in all, there was a cumulative 12% to 16% greater risk of OF per year of Viread use.
Presenter Dr. Roger Bedimo of the University of Texas Southwestern Medical Center said, “The significant increase seen in the HAART era is not necessarily cause and effect.” The research team hypothesized that the cause of the increased risk of OF was aging made possible by longer survival with HAART.
The presentation was complex. See the slides and hear the audio here.