HIV Testing Should Be Part of Routine Medical Care; Early Detection Can Lengthen Lifespan, Prevent Spread, Studies Suggest
Voluntary HIV testing should be a routine part of medical care in the United States, and early detection of the disease could add more than a year to the lifespan of HIV-positive patients at a cost comparable to other common screenings, including those for high blood pressure or breast cancer, according to two independent, federally funded studies published in the Feb. 10 issue of the New England Journal of Medicine, the Baltimore Sun reports (Niedowski, Baltimore Sun, 2/10). Since the 1980s when the HIV/AIDS epidemic began in the United States, health officials have recommended routine HIV testing only for people living in large cities with high HIV/AIDS prevalence rates or people in high-risk groups, such as injection drug users or men who have sex with men, according to the AP/New York Times. However, the studies suggest that the benefits of routine HIV testing, including a reduction in the number of new HIV infections and early treatment for HIV-positive patients, would outweigh the costs, the AP/Times reports. Health officials believe that about 30% of the 950,000 HIV-positive people living in the United States do not know they are infected (AP/New York Times, 2/10). Dr. Samuel Bozzette of RAND and the University of California-San Diego, who wrote an accompanying NEJM editorial, said that although 40% of U.S. residents had undergone HIV testing by the end of 2002, 40% of those diagnosed HIV-positive had not been tested until they showed symptoms of AIDS, according to the Los Angeles Times (Maugh, Los Angeles Times, 2/10).
Dr. David Paltiel of the department of epidemiology and public health at Yale University School of Medicine and colleagues from Harvard University created a computer model to compare routine, voluntary HIV testing with current testing practices in three hypothetical populations. The populations included a "high-risk" group with a 3% prevalence of undiagnosed HIV infection and 1.2% annual incidence; a "CDC threshold" group with a 1% prevalence of undiagnosed HIV infection and 0.12% annual incidence; and a "U.S. general" population group with a 0.1% prevalence of undiagnosed HIV infection and 0.01% annual incidence. The researchers then examined quality-adjusted survival, cost and cost-effectiveness of testing. The researchers found that the addition of a one-time HIV test for the high-risk group resulted in earlier diagnosis and an improved average survival time. The researchers calculated that the cost-effectiveness of a one-time HIV test for high-risk populations was $36,000 per quality-adjusted life-year gained. The cost-effectiveness of a test every five years was $50,000 per quality-adjusted life-year gained, and testing every three years cost $63,000 per quality-adjusted life-year gained. For the CDC threshold population, the researchers calculated that the cost-effectiveness of a one-time test was $38,000 per quality-adjusted life-year gained. Testing every five years cost $71,000 per quality-adjusted life-year gained, and testing every three years cost $85,000 per quality-adjusted life-year gained. In the U.S. general population group, a one-time screening cost $113,000 per quality-adjusted life-year gained. The researchers concluded that in all but the "lowest-risk" populations, routine, voluntary HIV testing every three to five years is "justified on both clinical and cost-effectiveness grounds." The researchers added that one-time testing for the general population might be cost-effective (Paltiel et al., New England Journal of Medicine, 2/10).
Dr. Douglas Owens, senior investigator at the Veterans Administration Palo Alto Medical Center and associate professor of medicine at Stanford University, and colleagues from Duke University developed a Markov model of costs, quality of life and survival associated with a routine, voluntary HIV testing program and compared the model with current testing practices. The researchers examined the cost-effectiveness of one-time screening both with and without considering the benefits to the sexual partners of the people who underwent testing. When considering only the benefits to an identified patient, the researchers found that with a 1% prevalence of unidentified HIV infection, a one-time screening program increased life expectancy by 3.92 days at a cost of $333 when compared with current testing practices, for a cost-effectiveness ratio of $41,736 per quality-adjusted life-year. Taking into consideration the costs and benefits to partners, one-time screening would cost $194 more than current practices and increase life expectancy by 5.48 days, resulting in an incremental cost-effectiveness ratio of $15,078 per quality-adjusted life-year. Including costs and benefits to sexual partners, the prevalence of unidentified HIV infection in a population can be as low as 0.05% before testing costs $50,000 per quality-adjusted life-year, according to the study. Testing every five years cost $57,138 per quality-adjusted life-year but would be "more attractive" than one-time testing in populations with a high incidence of HIV infection. The researchers concluded that routine, voluntary testing -- even among relatively low-prevalence populations -- is as cost-effective as "commonly accepted interventions, and such programs should be expanded" (Owens et al., New England Journal of Medicine, 2/10). The researchers concluded that one-time testing of the general population could reduce the annual U.S. HIV transmission rate by 20% and that HIV-positive people diagnosed through such testing could gain an average of 1.5 years of life, according to the AP/Houston Chronicle (Johnson, AP/Houston Chronicle, 2/9).
Paltiel said that what makes routine, voluntary testing in the general population "so imperative is that there are 900,000 people infected with HIV in this country, and 280,000 don't know it," adding, "They're unable to get access to lifesaving therapy, and we are unable to counsel them to prevent transmission of this disease. That's a huge failure of the public health process" (Sternberg, USA Today, 2/10). Rochelle Walenksy, an infectious disease specialist at Massachusetts General Hospital and a co-author of the first study, said, "The whole message that we're really trying to convey is: It's not about, 'Who should we test?' It's about, 'We should test everyone'" (Baltimore Sun, 2/10). Bozzette in his editorial wrote, "Given the availability of effective therapy and preventive measures, it is possible to improve care and perhaps influence the course of the epidemic through widespread, effective and cost-effective screening" (AP/Houston Chronicle, 2/9). According to Paltiel, CDC should be "much more aggressive" about implementing HIV testing for the general population, the Atlanta Journal-Constitution reports (Wahlberg, Atlanta Journal-Constitution, 2/10). Robert Janssen, director of HIV/AIDS prevention at CDC, said that the agency over the next two years will re-evaluate its testing guidelines and consider the results of the two studies and the availability of rapid HIV tests, according to the AP/Times (AP/New York Times, 2/10). "Should we consider testing the general population?" Janssen asked, adding, "It's an important question. But there are barriers." Janssen said the most significant barrier to testing the general population is that many insurance companies do not pay for routine HIV testing, according to the Journal-Constitution. In addition, some doctors say they are "too rushed" to test patients for HIV, and some people avoid getting tested because of stigma attached to the disease, the Journal-Constitution reports (Atlanta Journal-Constitution, 2/10).