 |
|
|
| |
HIV-negative men who have sex with men have lower CD4/CD8 ratios driven by higher absolute CD8 T-lymphocyte counts compared to HIV-negative heterosexual men
|
| |
| |
"Individuals who engage in high-risk sexual behavior can impact their body's immune system, according to a recent, AIGHD-led study. lifestyle impacts the CD4 to CD8 T-cell ratio in HIV-negative individuals....HIV-negative men who have sex with men have lower CD4 to CD8 ratios due to a higher CD8 T-cell counts compared to HIV-negative heterosexual men......high number of sexual partners had lower CD4 to CD8 ratios and higher CD8 T-cell counts than those who did not" from Jules: the risk factors for reduced immunity cross all demographics and include HIV itself, drug use, sexual behavior, despite that virology suppression & normalized CD4 reduce risk for immune depletion but they do not eliminate it, immune activation & inflammation due to HIV and other risk factors persists.
High Rate of Bone Thinning in Healthy Gay Men Without HIV
Reported by Jules Levin
20th International Workshop on Comorbidities and Adverse Drug Reactions in HIV
Oct 13-14 2018 NYC
SO Verboeket1,2, FW Wit1,2,3, E Verheij1,2, RA van Zoest1,2, M van der Valk1, MF Schim van der Loeff4, NA Kootstra5, P Reiss1,2,3
1Department of Global Health and Internal Medicine, Amsterdam Infection and Immunity Institute and Amsterdam Public Health Research Institute, University of Amsterdam, Amsterdam UMC, Amsterdam, the Netherlands;
2Amsterdam Institute for Global Health and Development, Amsterdam, the Netherlands;
3HIV Monitoring Foundation, Amsterdam, the Netherlands;
4Department of Infectious Diseases, Public Health Service of Amsterdam, Amsterdam, the Netherlands; 5Department of Experimental Immunology, University of Amsterdam, Amsterdam UMC, Amsterdam, the Netherlands
Objectives/aims: Ongoing immune activation in treated HIV infection, reflected amongst others in a persistently
low CD4–CD8 lymphocyte ratio, may contribute to age-related comorbidity risk. In men who have sex with men (MSM) the occurrence of a range of sexually transmitted infections (including HIV) and certain behavioural lifestyle factors are more common compared to the general population. Determining whether such factors in MSM without HIV affect the CD4–CD8 ratio could contribute to further our understanding of factors driving persistent immune activation, also in people living with HIV with undetectable HIV viraemia on treatment.
Methods: As part of the AGEhIV cohort-study an HIV-negative control group was recruited which included 80 men who only have sex with women (MSW, ≤1 lifetime male sex partner), 253 low-risk and 113 high-risk MSM (an average of ≤10 versus >10 sexual partners during the 6 months preceding study visits), all ≥45 years of age. At three consecutive biennial study visits flow cytometric T-lymphocyte immunophenotyping was performed. Linear mixed models, accounting for repeated measures, were used to evaluate differences in the CD4–CD8 ratio and the absolute CD4 and CD8 counts between MSW, low- and high-risk MSM. Using a step-wise forward model-building procedure we determined factors potentially mediating any observed differences between these subgroups.
Results: MSW had higher CD4–CD8 ratios (median, IQR; 2.21, 1.58–2.96) compared to both high-risk MSM (1.45, 1.04–1.92; P<0.001) and low-risk MSM (1.76, 1.29–2.39; P<0.001), with high-risk MSM having lower CD4–CD8 ratios compared to low-risk MSM (P<0.001). These differences were largely driven by higher CD8 cell counts, and were only partially explained by differences in demographics, substance-use (smoking and recreational drugs), evidence of microbial translocation (intestinal fatty acid binding protein levels) and recent STIs including Chlamydia trachoma tis, Neisseria gonorrhoeae, syphilis and chronic hepatitis B/C (Table 1).
Discussion: HIV-negative MSM, especially those with a high number of sexual partners, have increased CD8 counts resulting in lower CD4–CD8-ratios, likely to some extent resulting from a specific lifestyle and/or more frequent exposure to sexually transmitted pathogens. Ongoing investigations are addressing the possible additional role of cytomegalovirus exposure and antibody titre. These results provide insight into which factors, other than those more directly related to HIV, are likely to contribute to the persistent immune activation observed in people with treated HIV infection.
----------------------------
Posted at 10:27h
https://www.aighd.org/2018/10/15/engaging-in-high-risk-sexual-behavior-impacts-the-immune-system-aighd-study/
Individuals who engage in high-risk sexual behavior can impact their body's immune system, according to a recent, AIGHD-led study.
As part of the immune system, T-cells play an important role in helping ward off infections. It has been shown in prior research that people living with HIV may continue to have higher levels of chronic immune activation despite adequate treatment. This also includes a low CD4 to CD8 T-cell ratio, both because of higher levels of activated CD8 T-cells and reduced CD4 T-cells. Having higher levels of immune activation is also associated with the early and more frequent development of age-related illnesses, such as cardiovascular diseases.
It still remains to be determined why these levels of immune activation remain high in people with HIV who take appropriate medication to suppress their HIV-infection, and whether factors other than having HIV may play a role.
Sebastiaan Verboeket, a PhD student with the Amsterdam Institute for Global Health and Development, presented his research at the 20th International Workshop on Co-morbidities and Adverse Drug Reactions in HIV on Friday and showed that lifestyle impacts the CD4 to CD8 T-cell ratio in HIV-negative individuals.
Using data from the HIV-negative AGE IV cohort participants, of which 65% of participants were men who have sex with men (MSM), Sebastiaan determined that HIV-negative men who have sex with men have lower CD4 to CD8 ratios due to a higher CD8 T-cell counts compared to HIV-negative heterosexual men. Further, the HIV-negative MSM who, on average, had a high number of sexual partners had lower CD4 to CD8 ratios and higher CD8 T-cell counts than those who did not.
While researchers could not fully explain why there was a difference, they found that the MSM in the study had been infected with the cytomegalovirus (CMV) more often than the straight men. Many people become infected with this virus at some point during their lifetime and it usually causes little to no symptoms for people with well-functioning immune systems.
"This study is important because sexual risk behavior has, to my knowledge, not been investigated as a potential determinant for a lower CD4 to CD8 ratio and higher CD8 count in such a large HIV-negative cohort. We're now trying to tease out further which factor, CMV or sexual risk behavior, contributes the most," said Sebastiaan.
"These findings are relevant because about 70% of people living with HIV in the western world are also men who have sex with men. We show that when you want to determine the causes for persisting immune-activation in people living with treated HIV, it is important to not automatically ascribe everything to HIV, but to also take their lifestyle, including their sexual behavior, and other infections into account."
In acknowledgement of these important findings in his abstract HIV-negative men who have sex with men have lower CD4 to CD8 ratios driven by higher absolute CD8 T-lymphocyte counts compared to HIV-negative heterosexual men, Sebastiaan received the Dr. Robert Munk Award, which is given by the workshop organizing committee to the lead author of an excellent abstract submitted by a young investigator.
Dr. Robert Munk, who was openly living with HIV, sadly passed away in 2015 and was involved in AIDS activism since 1987. He was a long-term Scientific Committee member for the International Workshop on Co-morbidities and Adverse Drug Reactions in HIV. Amongst many achievements, he was the first development director for The NAMES Project in San Francisco before founding the AIDS Service Providers Association. In 1997, he founded AIDS InfoNet, an online patient education resource providing HIV treatment information in multiple languages.
|
| |
|
|
|
|
|
