Despite staggering scientific and medical advances, the HIV epidemic in the United States has not changed significantly over the past decade. The estimated incidence of HIV infection has remained stable overall, with between 45,000 and 55,000 new HIV infections diagnosed per year.
This is disheartening because, even without a vaccine, I believe we have the tools today to drive the epidemic down to zero. First of all, we know how to effectively diagnose and treat the infection, and we have evidence that antiretroviral treatment is an effective prevention tool. Secondly, advances in chemoprophylaxis have made pre-exposure prophylaxis a reality.
Ob.gyns. played a central role in one of the greatest successes of the use of antiretroviral drugs: the virtual elimination of mother-to-child transmission of HIV in the United States. Now, by fully utilizing the tools available today, ob.gyns. can play a critical role in ending the epidemic in the United States and beyond.
Tools for diagnosis and treatment
We have so many missed opportunities in fighting the HIV epidemic.
This is evident in data compiled for a model called the “HIV Care Continuum,” or HIV “Cascade of Care.” The model captures the sequential stages of HIV care from diagnosis to suppression of the virus. It was developed in 2011 by Dr. Edward Gardner, an infectious disease/HIV expert at Denver Public Health, and has since been used at the federal, state, and local levels to help identify gaps in HIV services.
Not too long ago, diagnosis was the biggest problem in reducing the public health burden of HIV. Today, the biggest problem is linking and keeping individuals in care. According to the latest analysis by the U.S. Centers for Disease Control and Prevention of the HIV Care Continuum , of the 1.2 million people estimated to be living with HIV in America in 2011, approximately 86% were diagnosed, but only 40% were linked to and stayed in care, 37% were prescribed antiretroviral therapy (ART), and 30% had achieved viral suppression.
Only 30% of Americans living with HIV infection today are effectively treated, according to these data, even though we have the drugs and drug regimens available to treat everyone effectively.
Other analyses have included an additional stage of being initially linked to care (rather than being linked to care and retained in care). This presentation of the cascade, or continuum, further illuminates the progressive drop-off and that shows why an effective, sustained linkage to care is a critical component to ending the HIV epidemic.
One of these studies – an analysis published in 2013 – showed that approximately 82% of people were diagnosed, 66% were linked to care, 37% were retained in care, 33% were prescribed antiretroviral therapy, and 25% had a suppressed viral load of 200 copies/mL or less ( JAMA. Intern. Med. 2013;173:1337-44 ).
With regard to women specifically, the CDC estimates that one in four people living with HIV infection are women, and that only about half of the women who are diagnosed with the infection are staying in care. Even fewer – 4 in 10 – have viral suppression, according to the CDC.
Expanding the management of HIV in the primary care setting could move us closer to ensuring that everyone in the United States who is infected with HIV is aware of the infection, is committed to treatment, and is virologically suppressed.
Like other primary care physicians, ob.gyns often have some degree of long-term continuity with patients – or the ability to create such continuity – that can be helpful for ensuring treatment compliance.
Ob.gyns also have valuable contact with adolescents, who fare worse throughout the cascade and are significantly more likely than older individuals to have unknown infections. An analysis published in 2014 of data for youth ages 13-29 shows that only 40% of HIV-infected youth were aware of their diagnosis and that an estimated 6% or less of HIV-infected youth were virally suppressed ( AIDS. Patient. Care. STDS. 2014;28:128-135 ).
HIV testing should occur much more frequently than a decade ago, given the move in 2006 by the CDC from targeted risk-based testing to routine opt-out testing for all patients aged 13-64.
Treatment, moreover, has become much simpler in many respects. We have available to us more than 30 different drugs for individualizing therapy and providing treatment that allows patients to live a natural lifetime.
While such a large array of options may require those ob.gyns. who see only a few HIV-infected patients a year to work in consultation with an expert, many of the regimens require only a single, once-a-day pill. And while there was much debate as recently as five years ago about when to start treatment, there now is consensus that treatment should be started immediately after diagnosis (even in pregnant women), rather than waiting for the immune system to show signs of decline.
In fact, there is growing evidence that early treatment is key for both the infected individual and for individuals at risk. In the HIV Prevention Trials Network 052 study of discordant couples, for instance, early antiretroviral therapy in an infected partner not only reduced the number of clinical events; it almost completely blocked sexual transmission of the virus to an HIV-negative partner ( N. Engl. J. Med. 2011;365:493-505 ).
The 052 study was a landmark “treatment as prevention” study. Other research has similarly shown that when the viral load of HIV-infected individuals is significantly reduced, their infectivity is reduced. And on a larger scale, research has shown that when we do this on a population basis, achieving widespread and continual treatment success, we can significantly impact the epidemic. This has been the case with the population of intravenous drug users in Vancouver, where the community viral load was significantly reduced by successful treatment that prevented new infections in this once-high-risk population.
Emerging data suggests that early diagnosis and treatment will likely also impact the likelihood of infected individuals achieving “functional cure.” The issue of functional cure – of achieving viral loads that are so low that drug therapy is no longer needed – has been receiving increasing attention in recent years, with the most promising findings reported thus far involving early treatment.
Tools for preexposure prophylaxis
For many years, we fit HIV care neatly into either the treatment or prevention category. More recently, we have come to appreciate that treatment is prevention, that a comprehensive prevention strategy must include treatment of infected individuals.
On the purely prevention side, it is important to continue educating women about safe sex behaviors. Most new HIV infections in women (84%) result from heterosexual contact, according to the CDC. For those who remain at risk of acquiring HIV despite education and counseling (eg., individuals who continue to engage in high-risk behaviors, or who have an HIV-positive partner), pre-exposure prophylaxis (PrEP) is now a safe and effective tool for preventing transmission. Patients deemed to be at high risk of acquiring HIV need to be made aware of this option.
PrEP originally was recommended only for gay or bisexual men, but in May 2014, the CDC recommended it for all individuals at risk and released the first comprehensive clinical practice guidelines for the prevention tool ( www.cdc.gov/hiv/pdf/guidelines/PrEPguidelines2014.pdf).
The PrEP medication, Truvada, is a combination of two drugs (tenovovir and emtricitabine) that, when taken daily on a consistent basis, significantly reduces the risk of getting HIV infection. Several large national and international studies have documented risk reductions of 73% to 92% when the medication was taken every day or almost every day. It is clearly within the purview of any ob.gyn to prescribe, monitor, and manage such prevention therapy.
The availability and relative ease of such a tool, along with advances in treatment and knowledge gained from the HIV Care Continuum, should re-energize ob.gyns. to up the ante in efforts to end the epidemic.
Experience in our clinical program that provides care and treatment to patients in the Baltimore-Washington area has taught us that we do much better when we integrate HIV care within primary care. It’s much more likely that patients will “stay close” with their ob.gyn than to another specialist.
Certainly, HIV infection has its “hot spots” and areas of much lower prevalence, but regardless of where we reside, we must continue to appreciate that the epidemic has had a significant impact on women and that this will persist unless we can all better utilize our available tools, such as early diagnosis and effective treatment that are linked long-term with other primary care physicians.
For women, ob.gyns represent a great resource for our nation to make progress toward President Obama’s National HIV Strategy.
Dr. Redfield reported that he has no disclosures relevant to this Master Class.