Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

AIDS study challenges conventional treatment guidelines for HIV patients

27.09.2006
National study published in curent issue of JAMA

A newly published study by investigators at the Center for AIDS Research at Case Medical Center, led by Benigno Rodríguez, MD, along with a nationwide team of AIDS/HIV experts, strongly challenges conventional thinking about the role of measurements of the amount of HIV particles in the blood as a method of predicting a patient's ability to fight off the disease. The study, published in the current issue of JAMA (Journal of the American Medical Association), indicates that the amount of HIV in a patient's blood (commonly known as the viral load) is much less reliable as a tool for determining the rate at which he or she will lose infection-fighting CD4 cells than previously thought.

HIV targets CD4 cells, a type of white blood cell, and as they decline after HIV infection, the complications that characterize the Acquired Immunodeficiency Syndrome (AIDS) become more common. These study results showed that the viral load explains only about 5% of the variation from person to person in the rate of CD4 cell loss. Thus, CD4 depletion cannot be viewed as a simple consequence of the amount of virus circulating in the blood.

"The results of this nationwide study may have profound implications in our understanding of how HIV causes disease and in our approach to the management of HIV-infected patients," says Dr. Rodriguez, infectious disease specialist at the Case Medical Center, a partnership of University Hospitals and Case Western Reserve University School of Medicine. "We hope that this study will provide impetus for a more thorough understanding of the mechanisms of HIV-induced damage to the immune system and for the design of strategies to block those mechanisms."

In the study, entitled Predictive Value of Plasma HIV RNA Level on Rate of CD4 T Cell Decline in Untreated HIV infection, Dr. Rodríguez and his colleagues report the results of analyses conducted on two large cohorts of HIV-infected patients who were not receiving treatment for HIV, totaling more than 2,800 individuals. The first cohort consisted of patients included in three data sources: a) four sites of the Centers for AIDS Research Network of Integrated Clinical Systems (CNICS), a database of real-time clinical care and laboratory data; b) the San Francisco Men's Health Study (SFMHS) and the Research in Access to Care for the Homeless Cohort (REACH). This cohort included approximately 12% female and 35% non- Caucasian participants. The second cohort, which the investigators used to validate their findings in the first group, included participants in the Multicenter AIDS Cohort Study, a long-standing federally funded study composed largely of Caucasian men who have sex with men.

The investigators sought to estimate how much of the person-to-person variation in the rate of CD4 cell loss could be accounted for on the basis of each patient's initial viral load, in an attempt to reproduce more closely the situation that a physician would encounter in clinical practice, where a patient presents with an initial set of laboratory results and the clinician must try to predict how quickly that person's CD4 cell count will reach the danger level at which treatment for HIV becomes most critical. Current clinical practice, based on previous work from other groups, is to focus on both the current CD4 count and the viral load to estimate how rapidly a person's CD4 cell count will decrease. This approach is based on comparisons of the average rate of CD4 cell loss among groups of patients with roughly similar viral loads, which indicate that generally speaking, patients with higher viral loads will tend to experience more rapid CD4 cell loss than patients with lower viral loads. Until now, however, there had been no attempt to quantify how well this observation held when considering the estimated rate of CD4 cell loss for each individual patient.

Using sophisticated statistical modeling, the researchers found that only 4-6% of an individual patient's CD4 cell loss rate can be explained by his or her presenting viral load. Moreover, the results were remarkably similar when the analyses were reproduced separately in each of the two cohorts, and changed only minimally when the investigators considered the possible effect of errors in the measurement of the CD4 cell count and the HIV viral load.

These results represent a shift in the paradigm that the rate of CD4 cell loss in a given HIV-infected individual can be accurately predicted by his or her viral load. Predicting disease progression is crucial in the treatment of HIV-positive people, such as in making the decision as to when it is best for starting antiretroviral therapy. Current treatment guidelines, while diminishing its importance, continue to include HIV viral load as one element in making decisions regarding when to begin antiretroviral therapy. Antiretroviral therapy, also known as HAART, is credited with saving millions of lives. However, potent side effects and issues of drug resistance, often cause doctors and patients to defer starting the medications, until it becomes medically necessary.

In addition to the clinical ramifications, the findings suggest that HIV-associated CD4 depletion cannot be thought of as a mere consequence of the amount of virus circulating in the blood. Instead, the findings suggest rather more complex scenarios of disease progression, and hint at indirect processes though which HIV can induce damage to the immune system, which cannot be adequately captured by measuring HIV levels in the blood.

Alicia Reale | EurekAlert!
Further information:
http://www.uhhs.com
http://casemed.case.edu

More articles from Studies and Analyses:

nachricht Multi-year study finds 'hotspots' of ammonia over world's major agricultural areas
17.03.2017 | University of Maryland

nachricht Diabetes Drug May Improve Bone Fat-induced Defects of Fracture Healing
17.03.2017 | Deutsches Institut für Ernährungsforschung Potsdam-Rehbrücke

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Northern oceans pumped CO2 into the atmosphere

27.03.2017 | Earth Sciences

Fingerprint' technique spots frog populations at risk from pollution

27.03.2017 | Life Sciences

Big data approach to predict protein structure

27.03.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>