After more than a decade of stagnation in the fight against HIV, the nation’s medical establishment has begun to support aggressive new screening recommendations designed to reduce the incidence of new infections and improve the quality of treatment for patients with HIV/AIDS.
The CDC led the way to a greater emphasis on HIV in 2006 with the release of guidelines advocating at least 1 round of routine testing for all Americans aged 13 to 64 years, in a wide range of medical settings. The CDC program advocates testing patients by default, with an option to “opt-out” in patients who do not wish to be tested.1
These guidelines were a substantial departure from earlier recommendations, which proposed a targeted screening strategy for people who sought HIV testing after engaging in risky behavior. Introduction of the older guidelines generated more analysis than action.
But subsequent developments have bolstered the CDC’s push for broader testing.
The Affordable Care Act (ACA) expanded eligibility for Medicaid programs that cover routine HIV testing in most states.2 The Obama administration followed that effort with a comprehensive HIV plan that also recommends expanded testing.3 Then, last year, the US Preventive Services Task Force (USPSTF) brought its HIV screening recommendations for primary care physicians (PCPs) in line with those of the CDC.4
Together, these developments may advance the implementation of broad, nontargeted screening programs, with the option to opt out. These policies are expected to precipitate an exponential increase in the number of patients receiving an HIV test.
Researchers disagree about whether the benefits of nontargeted testing will exceed the costs of such programs. Despite the controversy, medical officials believe a potential reduction in the incidence of new infections and the potential survival benefit with earlier diagnosis justify the costs.
The CDC has gone a step further, and this spring endorsed an even costlier tactic to prevent new infections among high-risk individuals: prophylactic daily doses of antiretroviral medications that cost thousands of dollars per year.5
Although the USPSTF has not yet issued an official position statement on the use of preexposure prophylaxis (or PrEP), USPSTF members believe that a shifting scientific consensus justifies the decision to support the CDC’s position on testing.
“Under the old guidelines, insufficient testing took place. The number of undiagnosed HIV cases crept up, and annual infec-tions remained at the 50,000 mark for more than a decade. Clearly, something had to change,” said Douglas Owens, MD, MS, a USPSTF member who is also director of the Center for Primary Care and Outcomes Research and the Center for Health Policy at the Stanford University School of Medicine.
Owens continued: “We made these changes because of compelling recent evidence about the importance of early HIV detection. First, many studies completed since the last guidelines show that patients fare much better if treatment begins before symptoms appear, and they can’t get treatment if they don’t know they have the disease. Second, studies released since the last report demonstrate that treatment reduces virus levels enough to greatly reduce disease transmission. Thus, finding more existing cases earlier would significantly reduce [the rate of] new infections.”
Health authorities have certainly struggled to get people who engage in high-risk behavior to get themselves tested. More than 10% of men who have sex with men (MSM) or have unprotected sex with multiple partners have never been tested.6
As a result, more than 240,000 Americans have undiagnosed cases of HIV at any given time.7 Many of them will not receive a diagnosis until they experience symptoms of HIV, meaning that patients will not receive early treatment and are more likely to spread the disease to others.
Research suggests that people with undiagnosed HIV account for fewer than 20% of all patients with HIV, but cause more than half of all new infections each year.8
Several statistical analyses have concluded that testing almost every American at least once would reduce the incidence of new infections and improve overall treatment quality.
One extensively cited model published in the Annals of Internal Medicine projected that one-time HIV screening of low-risk individuals, along with annual screening of high-risk individuals, could prevent 6.7% of a projected 1.23 million new infections over 20 years at a cost of $22,382 per quality-adjusted life-year (QALY) gained.9 Given that any intervention with a cost per QALY below $100,000 is generally deemed cost-effective,10 the predicted cost of HIV screening is favorable from the standpoint of value. (The same study concluded that combining the screening with better care could prevent more than 17% of infections and still cost slightly less per QALY.)
After the CDC published its testing recommendation, a number of real-world trials illustrated how difficult it will be to reduce the number of patients with undiagnosed
HIV with universal screening—and that the enterprise may cost far more per diagnosis than advocates previously expected.
Researchers in Colorado, for example, conducted a 2-year study at an urban emergency department (ED) that compared results for a year’s worth of the nontargeted opt-out screening recommended by the CDC with a year’s worth of physician-recommended testing for high-risk patients.
Providing tests for everyone on an opt-out basis boosted the total number of tests administered dramatically. ED staff tested nearly 30 times as many people during the opt-out phase (6933) as they did during the physician-directed testing phase (243), despite treating slightly more total patients during the latter period.11 They did not, however, come close to testing everyone between the ages of 13 and 64 years who came through the ED during the opt-out period. Nearly three-fourths of all patients declined HIV testing, even though the test was offered free of charge to everyone.
Other studies have found similar results. The switch from targeted, opt-in testing to nontargeted, opt-out testing increases test numbers dramatically, but 75% to 80% of all people consistently refuse screening.12
ED trials of nontargeted opt-out screening have also found that the cost per new diagnosis is very high.
To return to the Colorado study, just 15 of the 6933 patients (0.21%) who were tested during the full 12 months of opt-out testing received a new diagnosis of HIV. Of the 243 who were tested during the 12 months of targeted testing, 4 (1.6%) received new HIV diagnoses. So more than 6600 extra tests uncovered just 11 new cases.
In a second published paper that analyzed the trial financially, the Colorado researchers reported that total annualized costs were $148,997 for the nontargeted screening and $31,355 for the targeted testing.13 Thus the average cost per HIV diagnosis were $9932 and $7839, respectively, and the additional 11 HIV infections uncovered by nontargeted screening cost $10,693 apiece.
In theory, the benefit of 1 additional diagnosis could certainly justify such a cost, even from a purely financial perspective, if that early diagnosis prevented hospitalizations or new infections. Indeed, several studies have concluded that benefits outweigh costs even when new cases appear as infrequently as they did in the Colorado ED.14,15
Each prevented case of HIV represents a major savings. The lifetime costs of treating a person with HIV are currently estimated to be about $380,000.14 A single year of treatment with the brand name version of a 3-drug combination tablet— the current standard of care—has a retail cost of $20,000.15
But costs are subject to change, which makes cost-efficacy projections very difficult. For example, all 3 of the drugs in the current combination will soon be available from generic manufacturers, and the 1-year cost of treatment is expected to fall well under $1000. On the other hand, new drugs are under development.
Assessing the value of saving someone a lifetime of dealing with HIV is difficult. An averted infection may provide decades of benefits, but if a cure for HIV becomes available within 5 years, the value of preventing infections falls precipitously.
“You can make a statistical case that $10,000 per diagnosis produces net positives, but it’s hard to look at those numbers and believe nontargeted opt-out screening in EDs is an efficient use of society’s very limited resources, particularly when you consider that 75% to 80% of people consistently opt out of testing,” said Jason S. Haukoos, MD, MSc, director of research for the Department of Emergency Medicine at the Denver Health Medical Center and lead author on the Colorado ED study.
Nontargeted opt-out testing may make more sense in other settings, such as the offices of PCPs, and the new guidelines from the USPSTF may dramatically increase testing in such venues.
The task force has aimed its recommendations specifically at PCPs because they are best positioned to perform testing on a large proportion of Americans.
The nation’s 310 million residents visit PCPs a total of 550 million times per year,16 and many of those visits already entail having blood drawn to perform a host of standard tests. Adding an HIV test to each visit would require nothing extra from the patient, and adds less than $2 to the total per patient cost.17
(EDs, on the other hand, almost always use stand-alone rapid tests that cost anywhere from $30 to $60 each once overhead and labor costs are considered.18)
The USPSTF guidelines do not specifically recommend the cheaper blood tests. Indeed, Owens said doctors may be wise to choose rapid tests for new patients who might never return. That said, the logical choice for habitual patients would certainly be the dramatically cheaper blood test, so the cost per diagnosis might prove far less than ED studies have found.
As for costs to insured patients, there won’t be any. The ACA requires that private insurers completely cover all preventive procedures recommended by the USPSTF.
The other potential advantage to testing at primary care offices is that existing relationships between doctors and patients may push opt-out rates down from the very high levels seen at EDs, particularly when many patients already get routine blood tests for other problems.
The USPSTF guidelines warn physicians that HIV screening is an important priority that should not be forgotten, but must be provided with informed consent. The guidelines state: “HIV screening should be voluntary and done only with the patient’s knowledge and understanding. Patients should be informed orally or in writing that HIV testing will be performed, unless they decline (optout screening). Patients should also be offered the opportunity to ask questions and to decline testing.”
Predicting the effect of the task force recommendation will be difficult. Although the group’s endorsement does force insurance companies to cover the cost of HIV testing, the endorsement does not force physicians to embrace the practice of nontargeted testing or to recommend tests to patients who fall within new guidelines but seem unlikely to have the disease.
Still, there is some evidence that doctors were embracing the idea of wider HIV testing even before the USPSTF affirmed the CDC recommendations. In 1 study, the percentage of nonelderly adults who reported that a health care professional had ever suggested they take an HIV test rose from 19% in 2009 to 29% in 2011.19
An increase in testing recommendations did not translate into an increase in testing rates over the same period,20 but there is some evidence that testing efforts in the United States have lowered the percentage of patients with undiagnosed HIV. For several years, between 1985 and 2008, the CDC estimated that roughly 20% of patients with HIV had remained undiagnosed.7 A more recent report, based on surveillance conducted in 2011, estimated that the figure has fallen to 15.8%.21
Greatly expanded testing at primary care facilities may reduce that percentage further, but many experts believe that EDs have a unique role in finding undiagnosed cases and slowing the spread of the disease.
Indigent individuals contract HIV more frequently than their wealthier counterparts,22 and the delay between infection and diagnosis tends to be longer. A disproportionate amount of medical care for indigent populations is administered at EDs rather than PCP offices. Often, EDs are the only source of medical care for low-income individuals.
The disappointing results from studies of nontargeted, opt-out testing in the ED setting have already started many researchers looking for yet another approach, one that could find its way to the next set of guidelines.
According to Haukoos, “Some people believe the next logical step is to return to a more targeted screening approach, but to use more sophisticated tools to identify high-risk cases.”
“Our team has developed and validated a simple, 6-factor evaluation tool, and our experience with it in the ED shows not only that it increases the chance that any test will come back positive, but also that it reduces opt-out rates. Patients are simply more likely to agree to a test when you can provide them some concrete reason why they should take the test.”
Haukoos noted that other research teams were also testing ideas for better targeting, so the next major set of testing guidelines might actually shift back to targeted screening, at least in the context of EDs and as the prevalence of undiagnosed HIV decreases.
The CDC’s PrEP recommendations will likely spur more research in that largely unstudied area—research that could also refine future guidelines.
Meanwhile, observers expect to see a dramatic increase in nontargeted HIV screening and new data about its effectiveness in combating a disease that has steadily spread, in spite of a decade of disease prevention efforts.