Abstract
HIV Infection
Life Expectancy Rises in US and Canada
At present, a 20-year-old HIV-infected person on antiretroviral therapy (ART) living in North America can, in general, expect to live into his or her 70s; in other words, to have a life expectancy almost the same as non-HIV-infected young adult. Between 2000 and 2007, life expectancy among HIV-infected individuals 20 years of age or older in the United States and Canada who were on ART increased from 36.1 to 51.4 years, according to a new study. Differences between subpopulations in the study group drawn from the North American AIDS Cohort Collaboration on Research and Design (NA-ACCORD) were largely as anticipated, with lower life expectancy for non-whites, individuals with baseline CD4 counts less than 350 cells/mm3, and injection drug users. An unexpected finding was the higher life expectancy for men compared to women during the time period 2006–2007; life expectancy was comparable for the two sexes during the other time periods included in the study.
Source: Samji H, Cescon A, Hogg RS, et al. Closing the gap: increases in life expectancy among treated HIV-positive individual in the United States and Canada. PLoS One 2013;doi:10.1371/journal/pone/008135.
Initiating Drug Treatment on Diagnosis
In San Francisco, early intervention has taken on a new meaning with the start of a new program in which people diagnosed with HIV infection may begin treatment with antiretroviral drugs the same day of their diagnosis. As part of city health officials' goal of eradicating HIV among San Franciscans—and at an ambitious pace that includes reducing the rate of new infections by half over the next 3 years—this same-day intervention strategy aims to decrease viral loads in newly infected patients to improve their health and lower the risk that they will transmit the virus to others. At present, about 16,000 people in San Francisco are living with HIV, with just over 400 newly diagnosed cases adding to the disease burden each year—a figure down from 534 new infections in 2007. In the “treatment as prevention” concept being implemented in San Francisco, antiretroviral therapy is initiated before a weakening immune system signals progression towards the development of AIDS. Some groups would like to see this strategy used in HIV-negative men at risk to prevent infection.
Source: Allday E. S.F program pushes immediate HIV treatment. San Francisco Chronicle, 2013. Available at
Comparison of Rapid vs. Laboratory Testing
To determine how the choice of a test method—whether rapid point-of-care testing using blood or saliva samples, or laboratory-based testing—could affect detection and diagnosis of HIV infection, between 2003 and 2008, researchers used for analysis the results of more than 21,000 consecutive HIV tests performed using venous blood. For all of the samples, a determination of HIV status was based on an HIV antibody-plus-RNA test algorithm. For some of these samples, there were also linked oral fluid or finger-stick blood samples that were used for rapid HIV testing. The researchers compared the results from the screening antibody tests to those obtained using the antibody-plus-RNA algorithm. For samples that had negative or discrepant screening antibody results, they did retesting, including using newer tests. They concluded that while some rapid antibody tests are comparable to laboratory antibody tests for case detection when using blood samples, “oral fluid testing greatly reduces the ability to detect HIV.”
Pilcher et al. reported that “Among patients screened for HIV using oral fluid samples tested by the Oraquick Advance rapid test, only 86.6 percent (110/127) of HIV infections were detected, demonstrating a substantially lower sensitivity than any blood test. Of the six non-acute (i.e., blood antibody-positive) missed by oral fluid testing, all were detected by the Oraquick Advance device on the corresponding venous blood sample. Used on oral fluids, the Oraquick Advance test also had a slightly lower specificity than other tests, which resulted in a significantly lower positive predictive value (95.7 percent) for this oral fluid screening test than for any of the blood tests.”
The authors concluded that because the new rapid antigen-antibody “combo” immunoassays (so-called 4th-generation HIV tests) demonstrated the ability to detect HIV in the majority of acute cases that were missed by rapid antibody tests, these combo tests should replace antibody-only tests as a primary screening assay in high-risk HIV testing programs. However, they authors noted, “An important concern with the use of the newer “4th generation” combo assays for HIV screening is that each can return a relatively large proportion of screening test-positive, confirmatory antibody test-negative results, since initial supplemental/confirmation testing is restricted to supplemental antibody assays. HIV RNA testing on the initial sample is recommended to help establish true HIV status in patients with such discrepant results.”
Source: Pilcher CD, Louie B, Facente S, et al. Performance of rapid point-of-care and laboratory tests for acute and established HIV infection in San Francisco. PLoS One 2013; doi:10.1371/journal/pone.0080629.
Why Gay Men Are Shunning PrEP?
The US Food and Drug Administration (FDA) approved the use of the combination antiretroviral therapeutic Truvada (emtricitabine and tenofovir)—approved to treat HIV-infected patients in 2004—as an HIV preventive agent more than 18 months ago. While some HIV-negative gay men have embraced this concept, “In some quarters, the idea that healthy gay men should take a medication to prevent infection—an approach called pre-exposure prophylaxis, or PrEP—has met with hostility or indifference.” Yet of the approximately 50,000 new HIV infections in the US each year, more than half can be attributed to transmission between male sex partners. Adoption of PrEP is below expectations so far. Based on retail pharmacy sales figures, since January 2011, 1774 people had filled prescriptions for Truvada to be used for HIV prevention—and nearly half of those prescriptions were for women. Confusion may be part of the reason more gay men aren't adopting PrEP. After years of public health messages urging condom use, the idea that by taking Truvada they may be protected from HIV infection even if they don't use condoms may send mixed messages. While a recent study found that men who believed they were taking Truvada versus a placebo, and thus protected against HIV, did not tend to participate in more risky sexual behavior, there remains concern that condom use may seem less important with PrEP. Linked to that concern is the question of adherence, as a large clinical trial in men who have sex with men demonstrated that many did not take Truvada everyday as instructed. Nonadherence not only increases the risk of infection in sexually active gay men, and especially those who do not use condoms, but it also increases the risk that drug-resistant HIV strains will emerge. Other issues may be slowing broader preventive use of Truvada as well including reports that some health care providers may not be supportive of this strategy, and that a stigma associated with Truvada use as a preventive has emerged in social media.
Source: Tuller D. A resisted H.I.V. pill. The New York Times. December 31, 2013:D1–D6.
Rectal Bacterial Infections and HIV Risk
Pathela et al. compared the risk of HIV among men who have sex with men (MSM) who have had bacterial rectal sexually transmitted infections (STIs) with Chlamydia trachomatis (CT) and/or Neisseria gonorrhoeae (GC) with MSM who have not had these bacterial rectal STIs. The authors found that HIV incidence was significantly higher among MSM with rectal infections (6.67%) than among those without rectal infections (2.53%), supporting the hypothesis that bacterial rectal STIs are markers of HIV risk behavior. These findings suggest a role for screening for rectal STIs, conclude the authors, to target patients at increased risk for HIV who might benefit from HIV prevention strategies such as risk-reduction counseling and PreP.
Source: Pathela P, Braunstein SL, Blank S, et al. HIV incidence among men with and those without sexually transmitted rectal infections: estimates from matching against an HIV case registry. Clin Infect Dis 2013;57:1203–1209.
Increased Tuberculosis Risk in HIV-Exposed Infants
A study of HIV-infected mothers and their 6-month-old HIV-exposed infants in Kenya found that the babies had a high prevalence of tuberculosis (TB): 10.9% of 128 infants. Testing for TB infection was performed on cryopreserved peripheral blood mononuclear cells from the infants using T-SPOT.TB assays, which do not cross-react with BCG (avoiding false results due to BCG vaccination). A positive TB assay in an infant correlated with active TB in the mother.
Source: Cranmer LM, Kanyuogo M, Jonnalagadda SR, et al. High prevalence of tuberculosis infection in HIV-1 exposed Kenyan infants. Ped Infect Dis J 2013;doi:10.1097/INF.0000000000000124.
Declining Antiretroviral Therapy Adherence Over Time Is Not Universal
It is true that most studies demonstrate a reduction in ART adherence over time, but some do not—adherence may remain stable or even improve in some cases—and there may be much to learn from these discrepant findings and the clinical or organizational factors that may be associated with various patterns of adherence. Wilson et al. conducted a longitudinal study of pooled data from 11 studies of HIV infected adults receiving ART. They modeled and compared changes in adherence over time and found that while adherence tended to decline over time, though not in all of the studies, the decline was nonlinear, and how adherence changed over time demonstrated a substantial amount of variability. The authors identified a number of patterns of change in adherence and suggest future studies to identify factors correlated with these patterns.
Source: Wilson IB, Bangsberg DR, Shen J, et al. Heterogeneity among studies in rates of decline of antiretroviral therapy adherence over time: results from the multisite Adherence Collaboration on HIV 14 Study. J Acquir Immune Defic Syndr 2013;64:448–454.
Hepatitis C Infection
Antiviral Treatment Beneficial in Diabetes
The causal link between hepatitis C virus (HCV) infection, insulin resistance, and the development of diabetes mellitus led a group of Taiwanese researchers to study whether antiviral therapy for HCV would be associated with improved clinical outcomes among a cohort of HCV-infected individuals with diabetes. The treated patients received pegylated interferon plus ribavirin. The occurrence of end-stage renal disease (ESRD), ischemic stroke, and acute coronary syndrome (ACS) was recorded over an 8-year follow-up period. Risk of all three outcomes was significantly lower for the antiviral treatment group compared to the untreated group, with multivariate-adjusted hazard ratios of 0.16 for ESRD, 0.53 for ischemic stroke, and 0.64 for ACS.
Source: Hsu Y-C, Lin J-T, Ho HJ, et al. Antiviral treatment for hepatitis C virus infection is associated with improved renal and cardiovascular outcomes in diabetic patients. Hepatology 2013; doi:10.1002/hep.26892.
HCV Increases Risk of TB Drug Toxicity
In a prospective study of patients who received a diagnosis of tuberculosis, HCV, chronic hepatitis B, and HIV serostatus were determined at the time of TB diagnosis. The most common co-infection in this patient cohort was HCV, detected in 21% of individuals. Only 4.3% of patients had HBV infection, and 1.8% were HIV-infected. Of the total population, mild to moderate hepatotoxicity developed following initiation of anti-tuberculosis drug therapy. Based on multi-variable analysis, the authors determined that HCV is “an independent risk factor for incident anti-TB drug-induced hepatotoxicity.” Furthermore, “HCV co-infected patients developed hepatitis more quickly compared to HCV seronegative patients with TB.
Source: Lomtadze N, Kupreishvili L, Salakaia A, et al. Hepatitis C virus co-infection increases the risk of anti-tuberculosis drug-induced hepatotoxicity among patients with pulmonary tuberculosis. PLoS One 2013;doi:1371/journal.pone.0083892.