Author Interviews, CDC, JAMA / 16.02.2016
New Test Can Improve Detection of Early, Acute HIV Infections
MedicalResearch.com Interview with:
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Dr. Phillip Peters[/caption]
Philip J. Peters, M.D.
HIV Testing and Biomedical Interventions Activity Lead
Epidemiology Branch
CDC’s Division of HIV/AIDS Prevention
Medical Research: What is the background for this study? What are the main findings?
Dr. Peters: Acute HIV infection contributes disproportionately to HIV transmission and identifying individuals with acute HIV infection is critical to prevent further HIV transmission, as diagnosis can lead to several effective HIV prevention interventions. Acute HIV infection can be diagnosed with assays that detect either HIV RNA (the reference standard) or the p24 antigen (an HIV core protein), which are both detectable early after HIV infection and before an antibody response develops. HIV immunoassays that detect both the p24 antigen and anti-HIV antibody (fourth generation antigen/antibody [Ag/Ab] combination immunoassays) are currently being implemented as the initial screening test in the 2014 CDC and American Public Health Laboratories (APHL) recommended HIV diagnostic algorithm. In a prospective study we evaluated the performance of an HIV Ag/Ab combination assay to detect acute HIV infection compared with pooled HIV RNA testing in a high-prevalence population.
All participants were first screened with a rapid HIV test to detect established HIV infection (antibody detectable). All participants with a negative rapid HIV test result were then screened for acute HIV infection with an HIV Ag/Ab combination assay (index test) and pooled HIV-1 RNA testing. HIV RNA testing was the reference standard, with positive reference standard result defined as detectable HIV-1 RNA on an individual RNA test.
Among 86,836 participants with complete test results (median age, 29 years; 75.0% male; 51.8% men who have sex with men), acute HIV infection was diagnosed in 168 (0.19%). Acute HIV infection was detected in 134 (0.15%) participants with HIV Ag/Ab combination testing (acute HIV infection sensitivity, 79.8%) and in 164 (0.19%) with pooled HIV RNA testing (sensitivity, 97.6%; sensitivity comparison, p<0.001). Overall HIV Ag/Ab combination testing detected 82% of acute HIV infections detectable by pooled HIV RNA testing. Compared with rapid HIV testing alone (which detected established HIV infection), HIV Ag/Ab combination testing increased the relative HIV diagnostic yield (both established and acute HIV infections) by 10.4% and pooled HIV RNA testing increased the relative HIV diagnostic yield by 12.4%.
Dr. Phillip Peters[/caption]
Philip J. Peters, M.D.
HIV Testing and Biomedical Interventions Activity Lead
Epidemiology Branch
CDC’s Division of HIV/AIDS Prevention
Medical Research: What is the background for this study? What are the main findings?
Dr. Peters: Acute HIV infection contributes disproportionately to HIV transmission and identifying individuals with acute HIV infection is critical to prevent further HIV transmission, as diagnosis can lead to several effective HIV prevention interventions. Acute HIV infection can be diagnosed with assays that detect either HIV RNA (the reference standard) or the p24 antigen (an HIV core protein), which are both detectable early after HIV infection and before an antibody response develops. HIV immunoassays that detect both the p24 antigen and anti-HIV antibody (fourth generation antigen/antibody [Ag/Ab] combination immunoassays) are currently being implemented as the initial screening test in the 2014 CDC and American Public Health Laboratories (APHL) recommended HIV diagnostic algorithm. In a prospective study we evaluated the performance of an HIV Ag/Ab combination assay to detect acute HIV infection compared with pooled HIV RNA testing in a high-prevalence population.
All participants were first screened with a rapid HIV test to detect established HIV infection (antibody detectable). All participants with a negative rapid HIV test result were then screened for acute HIV infection with an HIV Ag/Ab combination assay (index test) and pooled HIV-1 RNA testing. HIV RNA testing was the reference standard, with positive reference standard result defined as detectable HIV-1 RNA on an individual RNA test.
Among 86,836 participants with complete test results (median age, 29 years; 75.0% male; 51.8% men who have sex with men), acute HIV infection was diagnosed in 168 (0.19%). Acute HIV infection was detected in 134 (0.15%) participants with HIV Ag/Ab combination testing (acute HIV infection sensitivity, 79.8%) and in 164 (0.19%) with pooled HIV RNA testing (sensitivity, 97.6%; sensitivity comparison, p<0.001). Overall HIV Ag/Ab combination testing detected 82% of acute HIV infections detectable by pooled HIV RNA testing. Compared with rapid HIV testing alone (which detected established HIV infection), HIV Ag/Ab combination testing increased the relative HIV diagnostic yield (both established and acute HIV infections) by 10.4% and pooled HIV RNA testing increased the relative HIV diagnostic yield by 12.4%.





















Dr. Lazovich[/caption]
MedicalResearch.com Interview with:
DeAnn Lazovich, Ph.D.
Associate Professor
Division of Epidemiology and Community Health
University of Minnesota
Minneapolis, MN 55454
Medical Research: What is the background for this study? What are the main findings?
Dr. Lazovich: In Minnesota, as well as nationally, melanoma rates have been increasing more steeply in women than men younger than age 50 years since about the mid-1990s. Some have speculated that this could be due to women's indoor tanning use, as women use indoor tanning much more than men do. We had data on indoor 
Prof. Bisgaard[/caption]
MedicalResearch.com Interview with:
Hans Bisgaard, MD, DMSc
Professor of Pediatrics
The Faculty of Health Sciences
University of Copenhagen
Head of the Copenhagen Prospective Studies on Asthma in Childhood
University of Copenhagen and Naestved Hospital
MedicalResearch: What is the background for this study? What are the main findings?
Dr. Bisgaard: Vitamin D deficiency has become a common health problem in westernized societies, possibly caused by a more sedentary indoor lifestyle and decreased intake of vitamin D containing foods. Vitamin D possesses a range of immune regulatory properties, and it has been speculated that vitamin D deficiency during pregnancy may affect fetal immune programming and contribute to asthma pathogenesis. Asthma often begins in early childhood and is the most common chronic childhood disorder. Observational studies have suggested that increased dietary vitamin D intake during pregnancy may protect against wheezing in the offspring, but the preventive effect of
Dr. Augusto Litonjua[/caption]
MedicalResearch.com Interview with:
Augusto A. Litonjua, MD, MPH
Associate Professor
Channing Division of Network Medicine
and Division of Pulmonary and Critical Care Medicine
Department of Medicine
Brigham and Women's Hospital
Harvard Medical School
Boston, MA 02115 USA
Medical Research: What is the background for this study? What are the main findings?
Response: Vitamin D deficiency has been hypothesized to contribute to the asthma and allergy epidemic. Vitamin D has been shown to affect lung development in utero. However, observational studies have shown mixed results when studying asthma development in young children. Since most asthma cases start out as wheezing illnesses in very young children, we hypothesized that vitamin D supplementation in pregnant mothers might prevent the development of asthma and wheezing illnesses in their offspring. We randomly assigned 881 pregnant women at 10 to 18 weeks' gestation and at high risk of having children with asthma to receive daily 4,000 IU vitamin D plus a prenatal vitamin containing 400 IU vitamin D (n = 440), or a placebo plus a prenatal vitamin containing 400 IU vitamin D (n = 436). Eight hundred ten infants were born during the study period, and 806 were included in the analyses for the 3-year outcomes. The children born to mothers in the 4,400 IU group had a 20% reduction in the development of asthma or recurrent wheeze compared to the children born to mothers in the 400 IU group (24% vs 30%, respectively; an absolute reduction of 6%). However, this reduction did not reach statistical significance (p=0.051).
Dr. Firas Abdollah[/caption]
MedicalResearch.com Interview with:
Firas Abdollah, M.D., F.E.B.U.
(Fellow of European Board of Urology) Urology Fellow with the Center for Outcomes Research, Analytics and Evaluation
Vattikuti Urology Institute at Henry Ford Hospital in Detroit
MedicalResearch: What is the background for this study? What are the main findings?
Dr. Abdollah: Cancer screening aims to detect tumors early, before they become symptomatic. Evidence suggests that detection and treatment of early-stage tumors may reduce cancer mortality among screened individuals. Despite this potential benefit, screening programs may also cause harm. Notably, screening may identify low-risk indolent tumors that would never become clinically evident in the absence of screening (overdiagnosis), subjecting patients to the harms of unnecessary treatment. Such considerations are central to screening for prostate and breast cancers, the most prevalent solid tumors in men and women, respectively. These tumors are often slow growing, and guidelines recommend against screening (non-recommended screening) for these tumors in individuals with limited life expectancy, i.e. those with a life expectancy less than 10 years. Unfortunately, our study found that this practice is not uncommon in the US. Using a nationwide representative survey conducted in 2012, we found that among 149,514 individuals 65 years or older, 76,419 (51.1%) received any prostate/breast screening. Among these, 23,532 (30.8%) individuals had a life expectancy of less than 10 years. These numbers imply that among the screened population over 65 years old, almost one in three individuals received a non-recommended screening. This corresponds to an overall rate of non-recommended screening of 15.7% (23,532 of 149,514 individuals).
Another important finding of our study was that there were important variations in the rate of non-recommended screening from state to state; i.e. the chance of an individual older than 65 to receive a non-recommended screening varies based on his/her geographical location in United States.
Finally, on a state-by-state level, there was a correlation (40%) between non-recommended screening for prostate and breast cancer, i.e. states that are more likely to offer non-recommended screening for
Dr. Rachael Callcut[/caption]
MedicalResearch.com Interview with:
Dr. Rachael Callcut M.D., M.S.P.H