Gender differences in immune response to HIV

From Kaiser News

New research showing that "a receptor molecule involved in the recognition of HIV-1 responds to the virus differently in women than in men," might "explain why HIV infection progresses faster to AIDS in women than in men with similar viral loads," the HealthDay/Greenville Daily Reflector reports. The study was conducted by researchers at the Ragon Institute of Massachusetts General Hospital, Massachusetts Institute of Technology and Harvard University and will be published in an upcoming issue of the journal Nature Medicine. Study authors also note that during the early stages of infection, women tend to have a stronger immune response to HIV than men, but then progress to AIDS more quickly. The different immune system response "then leads to differences in chronic T-cell activation, a known activator of disease progression, according to the researchers," the article states (7/13). Researcher Marcus Altfeld said the findings raise new questions about how sex hormones affect HIV in the body. "Focusing on immune activation separately from viral replication might give us new therapeutic approaches" to treating HIV, he added (AFP/Google News, 7/13).

HIV disease progression by hormonal contraceptive method: Secondary analysis of a randomized trial

[IRMA wonders what the implications are for some potentially contraceptive microbicides, which would be non-hormonal.]

Stringer, Elizabeth M; Levy, Jens; Sinkala, Moses; Chi, Benjamin H; Matongo, Inutu; Chintu, Namwinga; Stringer, Jeffrey SA

AIDS: 17 July 2009 - Volume 23 - Issue 11 - p 1377-1382

Background: HIV-infected women need access to safe contraception. We hypothesized that women using depomedroxyprogesterone acetate (DMPA) contraception would have faster HIV disease progression than women using oral contraceptive pills (OCPs) and nonhormonal methods.

Methods: In a previously reported trial, we randomized 599 HIV-infected women to the intrauterine device (IUD) or hormonal contraception. Women randomized to hormonal contraception chose between OCPs and DMPA. This analysis investigates the relationship between exposure to hormonal contraception and HIV disease progression [defined as death, becoming eligible for antiretroviral therapy (ART), or both].

Results: Of the 595 women not on ART at the time of randomization, 302 were allocated to hormonal contraception, of whom 190 (63%) initiated DMPA and 112 (37%) initiated OCPs. Women starting IUD, OCPs, or DMPA were similar at baseline. Compared with women using the IUD, the adjusted hazard of death was not significantly increased among women using OCPs [1.24; 95% confidence interval (CI) 0.42-3.63] or DMPA (1.83; 95% CI 0.82-4.08). However, women using OCPs (adjusted hazard ratio (AHR) 1.69; 95% CI 1.09-2.64) or DMPA (AHR 1.56; 95% CI 1.08-2.26) trended toward an increased likelihood of becoming eligible for ART. Women exposed to OCPs (AHR 1.67; 95% CI 1.10-2.51) and DMPA (AHR 1.62; 95% CI 1.16-2.28) also had an increased hazard of meeting our composite disease progression outcome (death or becoming ART eligible) than women using the IUD.

Conclusion: In this secondary analysis, exposure to OCPs or DMPA was associated with HIV disease progression among women not yet on ART. This finding, if confirmed elsewhere, would have global implications and requires urgent further investigation