December 2nd, 2011 | Posted in HIV/AIDS
by Jay Gribble, vice president, International Programs
As part of World AIDS Day, ICFP 2011 included a special session on the recently published The Lancet article that found an increase—a two-fold increase—in the risk of contracting HIV among women who use injectable contraceptives. One of the speakers, a professional journalist, focused her comments on how she covered the study and how responsible journalists might cover such studies. I found her comments especially interesting given PRB’s longstanding work in training journalists to better understand health and population issues.
One of her points that stood out in my mind is the weighing of risks and benefits—a critical aspect of the ethical considerations of undertaking a study that involves human subjects. Evaluating risks and benefits is useful in helping an individual decide whether to participate in a study. While there isn’t necessarily an algorithm that can help individuals estimate their own risks and benefits, risks and benefits are frequently expressed at an aggregate level, based on the experience of all people participating in the study.
In this case of above-mentioned study, the news story headline stated that women using injectable contraception were twice as likely to contract HIV as were women who didn’t use that form of family planning. Those were the findings at the aggregate level, but that isn’t necessarily how people will interpret the findings. Given that readers are likely to interpret the findings based on their own context, a woman hearing about the story in Swaziland—with HIV prevalence of more than 25 percent–may interpret the findings quite differently than a woman in Senegal might—where HIV prevalence is less than 1 percent. When interpreting research study findings, it is critical to interpret them in light of the study context and to be careful about extrapolating findings to other settings.
The journalist went on to say that the relationship between the use of hormonal contraception and the increased risk of contracting HIV is not new; it extends back as far back as 25 years ago. So while the question is not new, it remains unanswered. Meetings to be held in December 2011 and January 2012 will discuss the need and feasibility of conducting a randomized trial to evaluate the causality of hormonal methods increasing the risk of contracting HIV. If deemed feasible, it is still not likely to resolve the question. Women who opt to participate in the study will be randomized to a method-specific arm—which may not be the method they really want to use, thus, increasing the risk of discontinuation. Women will also have to use the method correctly, whether it be pill, injectable, or other method. Finally, researchers will have to monitor the hormonal level in women’s bloodstream at the time of infection. Needless to say, if a randomized trial moves forward, it will be a very challenging study to design, carry out, and interpret
And while use of hormonal methods represent a large portion of the modern contraception used by African women, another comment that garnered an appreciative response was that the limited access to long-acting and permanent methods—including IUDs, tubal ligation, and vasectomy—means that women and men have limited access to a full range of methods, even if they want to limit childbearing. Given that long-acting and permanent methods have better continuity of use than short-term methods, and they have high efficacy rates and low failure rates, improving access to these methods can help create a more balanced method mix that responds to women’s and men’s needs.
The question raised by the study—and previous studies—remains unanswered. And even if we have a definitive answer, people will still need to consider their own circumstances in determining what contraceptive method to use. An individual’s circumstances will matter in choosing a method of family planning, as well as risk of contracting HIV. Epidemiological evidence will help understand macro-level relationships between use of hormonal methods and increased risk of HIV, but that evidence will also need to be evaluated in light of each woman’s context, too.