Although sex and gender bias is a known phenomenon in medicine, it is a particularly challenging issue in HIV research and treatment. Worldwide, women constitute more than half of all people living with HIV.1 There are many factors that play a role in women continuing to be underrepresented within HIV research.
- Biological and epidemiological differences in HIV between men and women.
- Sex-specific differences in HIV viral load and CD4 cell count.
- Sex-specific barriers and facilitators of improved antiretroviral therapy (ART) adherence.
- Impact of ART on contraception and fertility of HIV-positive women
- Sex-differences in HIV persistence.
- Barriers to enroll women in HIV cure research.
Sara Gianella, MD, assistant professor of medicine, and Maile Young Karris, MD, assistant professor of medicine, both at the University of California, San Diego, Center for AIDS Research, met with Infectious Disease Advisor to discuss these factors.
Infectious Disease Advisor: Dr Gianella, how does the epidemiology of HIV differ between men and women?
Sara Gianella, MD: In the United States, Western Europe, and Australia, the HIV/AIDS epidemic is driven by men, and especially men who have sex with men (MSM), while globally more than half of all people living with HIV are women. This is especially true in low-income and middle-income countries.2 This unequal geographical distribution is one of the reasons why underrepresentation of women in HIV research continues. In fact, most HIV-related research and clinical trials are conducted in higher-income countries, where the proportion of HIV-infected women is lower.3 Consequently, traditional recruitment strategies are designed to target men more than women. Competing priorities (childcare, home responsibilities, and shift work, among others) often make these strategies less successful for women. Due to an increasingly challenging financial climate and pressure to enroll participants in clinical trials efficiently, researchers often rely on established practices and draw from the same pools of participants.2 It is becoming clear that different strategies are needed to recruit and retain women into clinical trials for HIV.
We also need to account for differences in race and socioeconomic status when reaching out to HIV-positive women. For example, black women, Latino women, and sex workers are disproportionately affected by HIV/AIDS. Unfortunately, these populations do not always have access to high-quality HIV care, and therefore are even less likely to enroll in clinical trials.
That being said, I am thankful for continued federal funding for HIV clinical trials because federally funded trials tend to enroll higher proportions of women compared to industry-sponsored studies. For example, many large trials performed as part of the AIDS Clinical Trial Group (ACTG) include both domestic and international sites and are able to enroll women in proportions ranging from 20% to 25%. Depending on the sample size, these numbers are often sufficient to make fairly robust statistical conclusions about sex differences. These studies should serve as models for recruitment strategies applied to other settings and trials.