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To Screen or Not to Screen: Is That Really the Question?

2006; American College of Physicians; Volume: 145; Issue: 11 Linguagem: Inglês

10.7326/0003-4819-145-11-200612050-00011

1539-3704

Bernard M. Branson,

Sex work and related issues

Editorials5 December 2006To Screen or Not to Screen: Is That Really the Question?FREEBernard M. Branson, MDBernard M. Branson, MDFrom the Centers for Disease Control and Prevention–Division of HIV/AIDS Prevention, Atlanta, Georgia.Search for more papers by this authorAuthor, Article, and Disclosure Informationhttps://doi.org/10.7326/0003-4819-145-11-200612050-00011 SectionsAboutVisual AbstractPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail Few diagnostic tests or screening procedures have engendered as much controversy as the HIV test. From the inception of HIV testing, unique social issues have complicated deliberations about HIV testing. In 1985, when the HIV antibody test was first introduced, evidence suggested that approximately half of persons who were antibody-positive would become persistently infected carriers, and only 10% would develop AIDS (1).No effective treatment existed, and specific pretest counseling evolved (based on models used with genetic testing for untreatable conditions) to ensure that persons who sought HIV testing were aware of the uncertain meaning of a positive test result. In the context of widespread fear, stigma, and concern about discrimination, many states adopted requirements for separate written consent for HIV testing and established dedicated HIV testing sites, often outside of health care facilities, to allow anonymous testing. Routine HIV screening was unheard of except for blood donors.Once studies showed that HIV was highly fatal, the Centers for Disease Control and Prevention (CDC) recommended HIV counseling and testing for persons at high risk and patients at hospitals with HIV prevalence rates greater than 1%. The discovery that zidovudine prophylaxis reduced perinatal transmission by two thirds led directly to a recommendation to screen all pregnant women. As of 2002, 38% of adults aged 18 to 64 years (68 million people) reported that they had been tested for HIV at least once; an estimated 16 to 18 million adults are tested annually (2). However, an estimated one quarter of the approximately 1 million to 1.2 million HIV-infected persons in the United States are unaware that they are infected (3). Infection often remains undiagnosed until late in the course of disease despite multiple encounters with the health care system (4, 5). With the advent of effective treatment, clinicians and public health officials have increasingly called for expanded routine screening (6, 7), and the CDC recently recommended HIV screening in health care settings for all patients aged 13 to 64 years (8).In this issue, Paltiel and colleagues (9) examine the cost-effectiveness of HIV screening with rapid tests, using a sophisticated cost–utility analysis that expresses benefits as gains in quality-adjusted life-years (QALYs). The authors consider the medical benefits to individual patients and investigate several assumptions—both favorable and unfavorable—about the effects of earlier HIV diagnosis and treatment on subsequent transmission. Their conclusion: Routine, one-time rapid HIV testing for all adult patients is cost-effective even when the prevalence of undiagnosed HIV infection is as low as 0.2% (assuming that earlier diagnosis and antiretroviral treatment reduces HIV transmission). Screening is still cost-effective under unfavorable assumptions about the effects on subsequent transmission, but only at a somewhat higher prevalence (0.4%). The unfavorable transmission scenario assumes that HIV screening and treatment increase HIV transmission by prolonging life (and therefore the duration of infectiousness) and that infected persons might increase sexual risk-taking because they mistakenly think that having an undetectable viral load means that they are not infectious. The conclusion about the cost-effectiveness of screening is based on the conventional premise that interventions that produce a QALY for $50 000 or less are a bargain (10). Paltiel and colleagues also show that HIV screening remains cost-effective at an even lower prevalence of undiagnosed HIV infection if early detection leads to a more pronounced reduction in subsequent transmission or if society is willing to pay more than $50 000 per QALY.How does the cost-effectiveness of HIV screening in Paltiel and colleagues' study compare with the cost-effectiveness of other HIV screening programs? Since 1995, when the CDC recommended HIV testing for all pregnant women, the number of infants born annually in the United States with HIV infection has decreased more than 90%. In 2002, nearly 70% of the 4 million women who became pregnant reported that they had been tested for HIV during prenatal care (11). Prenatal screening averts as many as 1500 neonatal HIV infections per year. It is cost-saving wherever the HIV prevalence among pregnant women is more than 0.2% and costs less than $50 000 per QALY until HIV prevalence falls below 0.0075% (12). Current policies for testing donated blood are at the other extreme of cost-effectiveness. HIV antibody screening of the 15 million units of blood collected annually averts 1568 infections per year and costs $3600 per QALY (13). Pooled nucleic acid testing for HIV and hepatitis C virus (HCV) was added to the battery of screening tests for donated blood in 1999. According to current estimates, this additional screening averts an additional 4 HIV and 56 HCV infections annually, at a cost of $4.3 million per QALY (14).The CDC now recommends HIV screening for all adults, which means that HIV screening should become routine practice in primary care offices. Routine HIV screening is likely to be more cost-effective than Paltiel and colleagues suggest. Their model, like other recent analyses (15–17), includes pretest counseling, which costs 3 times more than the rapid HIV test. In addition to increasing the cost, requirements for pretest counseling might also diminish physicians' willingness to perform HIV screening. Because of competing demands, many clinicians already have difficulty providing all the preventive services recommended for their patients. A recent study in a primary care practice suggests that physicians are more likely to conduct screening than counseling: Patients were up to date on 55% of recommended screening services but on only 9% of health habit counseling (18). These considerations, and equivocal evidence for the effectiveness of counseling for persons who have negative test results, led the CDC to recommend HIV screening on the same voluntary basis as other screening or diagnostic tests—without pretest counseling or separate, written consent. Counseling efforts should focus on patients most likely to benefit: those with positive HIV test results and patients who have negative test results but engage in high-risk behaviors (8).Cost-effectiveness models for infectious diseases like HIV often underestimate the ultimate benefits to society. HIV is a communicable, fatal disease for which there is effective treatment but no cure. Paltiel and colleagues conclude that HIV screening is cost-effective when only the medical benefits to infected patients are considered, which is the usual basis for decisions about practice guidelines. However, they modeled the effects on subsequent transmission primarily on the basis of the potential for antiretroviral therapy to reduce infectiousness. They also restricted their benefit calculations to “first-generation” secondary transmissions—that is, new infections attributable to patients who are already infected, but not subsequent transmissions from the persons they might infect. It is crucial to more accurately quantify the many ramifications of early detection and treatment of HIV on overall transmission dynamics. Most patients, after learning that they are infected, take steps to protect their partners; these steps substantially reduce HIV transmission. The aggregate annual transmission rate for persons unaware of their HIV infection is estimated to be 6.9% compared with 2.0% for persons who are aware (19). This reduction in transmission is similar to that achieved with zidovudine prophylaxis to reduce the risk for perinatal transmission, and could have substantial implications for curbing the HIV epidemic. Many of the essential parameters needed to guide decisions about screening—including the prevalence of undiagnosed HIV infection in specific settings, the optimal frequency for retesting, and the ultimate effects on the course of the epidemic—will be known with certainty only after we implement screening and examine the results.No other industrialized country has instituted HIV screening for all patients. Nonetheless, the new U.S. policy seems proportionate to the problem, because few industrialized countries have an HIV/AIDS epidemic as severe as that of the United States. Current testing practices have successfully identified HIV in approximately 75% of infected patients. However, progress has stalled. An estimated 40 000 new HIV infections continue to occur each year. Nearly 40% of infected patients are not tested for HIV until they develop symptoms, after they have been infected—and infectious—for a decade. The prevalence of undiagnosed HIV infection is likely to fall within Paltiel and colleagues' range for cost-effective screening in most practice settings. The 1999–2002 National Health and Nutrition Examination Survey estimates that HIV prevalence is 0.43% in the U.S. adult population and is considerably higher among African Americans: 1.42% among non-Hispanic blacks 18 to 39 years of age and 3.58% among those aged 40 to 49 (20). Consistent with CDC estimates, 25% of persons infected with HIV did not know they were infected.The CDC's recommendation for opt-out screening is designed to make HIV screening more practical for both physicians and their patients. Patients are free to decline the test without recrimination, and they do not need to admit to some past indiscretion to qualify for testing. Physicians can provide information about HIV testing easily and effectively, with such aids as the prescription-like tear-off sheet developed by the American College of Obstetricians and Gynecologists. HIV screening can bring lifesaving information to infected patients earlier, when it is most beneficial, helping them to protect themselves and their partners. Eventually, reminiscent of successful screening programs for syphilis and tuberculosis, the cost-effectiveness question for HIV will change from whether we should screen for HIV to when we should stop.Bernard M. Branson, MDCenters for Disease Control and PreventionAtlanta, GA 30333References1. Francis DP, Jaffe HW, Fultz PN, Getchell JP, McDougal JS, Feorino PM. The natural history of infection with the lymphadenopathy-associated virus/human T-lymphotropic virus type III. Ann Intern Med. 1985;103:719-22. [PMID: 2996406] LinkGoogle Scholar2. Number of persons tested for HIV—United States, 2002. MMWR Morb Mortal Wkly Rep. 2004;53:1110-3. [PMID: 15573028] MedlineGoogle Scholar3. Glynn M, Rhodes P. Estimated HIV prevalence in the United States at the end of 2003 [Abstract]. Presented at the National HIV Prevention Conference, Atlanta, Georgia; 12-15 June 2005. Google Scholar4. Klein D, Hurley LB, Merrill D, Quesenberry CP; Consortium for HIV/AIDS Interregional Research. Review of medical encounters in the 5 years before a diagnosis of HIV-1 infection: implications for early detection. J Acquir Immune Defic Syndr. 2003;32:143-52. [PMID: 12571523] CrossrefMedlineGoogle Scholar5. Liddicoat RV, Horton NJ, Urban R, Maier E, Christiansen D, Samet JH. Assessing missed opportunities for HIV testing in medical settings. J Gen Intern Med. 2004;19:349-56. [PMID: 15061744] CrossrefMedlineGoogle Scholar6. Beckwith CG, Flanigan TP, del Rio C, Simmons E, Wing EJ, Carpenter CC, et al. It is time to implement routine, not risk-based, HIV testing. Clin Infect Dis. 2005;40:1037-40. [PMID: 15824997] CrossrefMedlineGoogle Scholar7. Frieden TR, Das-Douglas M, Kellerman SE, Henning KJ. Applying public health principles to the HIV epidemic. N Engl J Med. 2005;353:2397-402. [PMID: 16319391] CrossrefMedlineGoogle Scholar8. Branson BM, Handsfield HH, Lampe MA, Janssen RS, Taylor AW, Lyss SB, et al; Centers for Disease Control and Prevention (CDC). Revised recommendations for HIV testing of adults, adolescents, and pregnant women in health-care settings. MMWR Morb Mortal Wkly Rep. 2006;55 RR-14 1-17. [PMID: 16988643] MedlineGoogle Scholar9. Paltiel AD, Walensky RP, Schackman BR, Seage GR, Mercincavage LM, Weinstein MC, et al. Expanded HIV screening in the United States: effect on clinical outcomes, HIV transmission, and costs. Ann Intern Med. 2006;145:797-806. LinkGoogle Scholar10. Ubel PA, Hirth RA, Chernew ME, Fendrick AM. What is the price of life and why doesn't it increase at the rate of inflation? Arch Intern Med. 2003;163:1637-41. [PMID: 12885677] CrossrefMedlineGoogle Scholar11. Anderson JE, Sansom S. HIV testing among U.S. women during prenatal care: findings from the 2002 National Survey of Family Growth. Matern Child Health J. 2006;10:413-7. [PMID: 16770699] CrossrefMedlineGoogle Scholar12. Immergluck LC, Cull WL, Schwartz A, Elstein AS. Cost-effectiveness of universal compared with voluntary screening for human immunodeficiency virus among pregnant women in Chicago. Pediatrics. 2000;105:54-63. [PMID: 10742375] CrossrefMedlineGoogle Scholar13. AuBuchon JP, Birkmeyer JD, Busch MP. Cost-effectiveness of expanded human immunodeficiency virus-testing protocols for donated blood. Transfusion. 1997;37:45-51. [PMID: 9024489] CrossrefMedlineGoogle Scholar14. Jackson BR, Busch MP, Stramer SL, AuBuchon JP. The cost-effectiveness of NAT for HIV, HCV, and HBV in whole-blood donations. Transfusion. 2003;43:721-9. [PMID: 12757522] CrossrefMedlineGoogle Scholar15. Sanders GD, Bayoumi AM, Sundaram V, Bilir SP, Neukermans CP, Rydzak CE, et al. Cost-effectiveness of screening for HIV in the era of highly active antiretroviral therapy. N Engl J Med. 2005;352:570-85. [PMID: 15703422] CrossrefMedlineGoogle Scholar16. Walensky RP, Weinstein MC, Kimmel AD, Seage GR, Losina E, Sax PE, et al. Routine human immunodeficiency virus testing: an economic evaluation of current guidelines. Am J Med. 2005;118:292-300. [PMID: 15745728] CrossrefMedlineGoogle Scholar17. Paltiel AD, Weinstein MC, Kimmel AD, Seage GR, Losina E, Zhang H, et al. Expanded screening for HIV in the United States—an analysis of cost-effectiveness. N Engl J Med. 2005;352:586-95. [PMID: 15703423] CrossrefMedlineGoogle Scholar18. Stange KC, Flocke SA, Goodwin MA, Kelly RB, Zyzanski SJ. Direct observation of rates of preventive service delivery in community family practice. Prev Med. 2000;31:167-76. [PMID: 10938218] CrossrefMedlineGoogle Scholar19. Marks G, Crepaz N, Janssen RS. Estimating sexual transmission of HIV from persons aware and unaware that they are infected with the virus in the USA. AIDS. 2006;20:1447-50. [PMID: 16791020] CrossrefMedlineGoogle Scholar20. McQuillan GM, Kruszon-Moran D, Kottiri BJ, Kamimoto LA, Lam L, Cowart MF, et al. Prevalence of HIV in the US household population: the National Health and Nutrition Examination Surveys, 1988 to 2002. J Acquir Immune Defic Syndr. 2006;41:651-6. [PMID: 16652040] CrossrefMedlineGoogle Scholar Comments0 CommentsSign In to Submit A Comment Curt G BeckwithBrown Medical School8 January 2007 Routine HIV Testing in Jails We applaud Drs. Paltiel and co-authors and Dr. Branson for their recent articles [1-2] that support routine HIV testing. However, their recommendation for routine, voluntary HIV testing as part of primary medical care may miss most of the 750,000 individuals who are incarcerated in U.S. jails on any given day [3]. Most of these individuals do not have primary care providers and are not clients of our nations' mainstream healthcare system. The prevalence of known HIV infection in U.S. jails is estimated to be 1.3 % [4] which is over 3 times greater than the prevalence rate for the general U.S. population however the true HIV prevalence in jails may be significantly higher. An estimated one-fourth of all people living with HIV in the U.S. each year are released from a correctional facility that same year [5]. In particular, African-American men (the demographic group with the highest rate of HIV infection) are incarcerated in jail five times more frequently than White men [3]. The Centers for Disease Control and Prevention recommend routine opt-out HIV testing in incarcerated settings but most jails have not yet implemented it. Focused advocacy is needed now by AIDS activists and the public health community to initiate routine HIV testing in jails with real possibility for opt-out voluntary testing, appropriate protection for confidentiality of results, and linkage to HIV care both within correctional facilities and in the community post-release. 1. Paltiel DA, Walensky RP, Schackman BR, Seage GR, Mercincavage LM, Weinstein MC, et al. Expanded HIV screening in the United States: Effect on clinical outcomes, HIV transmission, and costs. Ann Int Med. 2006; 145: 797-806. 2. Branson BM. To screen or not to screen: Is that really the question? Ann Intern Med. 2006; 145: 857-859. 3. Harrison PM, Beck AJ. Prison and jail inmates at midyear 2005. NCJ publication no. 213133. Bureau of Justice Statistics, US Department of Justice, Office of Justice Programs. Washington, DC, 2006. 4. Maruschak LM. HIV in prisons and jails, 2002. NCJ publication no. 205333. Bureau of Justice Statistics, US Department of Justice, Office of Justice Programs. Washington, DC, 2004. 5. Hammett TM, Harmon MP, Rhodes W. The burden of infectious disease among inmates of and releasees from U.S. correctional facilities, 1997. Am J Public Health. 2002; 92: 189-94. Conflict of Interest: None declared Bernard HirschelGeneva University Hospital13 December 2006 Risk of HIV transmission with undetectable viral load To quote the author: "The unfavorable transmission scenario assumes that HIV screening and treatment increase HIV transmission by prolonging life (and therefore the duration of infectiousness) and that infected persons might increase sexual risk-taking because they mistakenly think that having an undetectable viral load means that they are not infectious." Why "mistakenly"? HIV viral load is by far the most important determinant of infectiousness (1). Where is the evidence that transmission from persons with a undetectable viral load play a role in the HIV epidemic? Even isolated case reports are difficult to find. (1) Quinn,T.C.; Wawer,M.J.; Sewankambo,N.; Serwadda,D.; Li,C.; Wabwire-Mangen,F.; Meehan,M.O.; Lutalo,T.; Gray,R.H. Viral load and heterosexual transmission of human immunodeficiency virus type 1. Rakai Project Study Group. N Engl J Med 2000;342:921-29. Conflict of Interest: None declared Author, Article, and Disclosure InformationAuthors: Bernard M. Branson, MDAffiliations: From the Centers for Disease Control and Prevention–Division of HIV/AIDS Prevention, Atlanta, Georgia.Disclaimer: The findings and conclusions in this report are those of the author and do not necessarily represent the views of the Centers for Disease Control and Prevention.Disclosures: None disclosed.Corresponding Author: Bernard M. Branson, MD, CDC–Division of HIV/AIDS Prevention, 1600 Clifton Road, MS D-21, Atlanta, GA 30333; e-mail, [email protected]gov. PreviousarticleNextarticle Advertisement FiguresReferencesRelatedDetailsSee AlsoExpanded HIV Screening in the United States: Effect on Clinical Outcomes, HIV Transmission, and Costs A. David Paltiel , Rochelle P. Walensky , Bruce R. Schackman , George R. Seage III , Lauren M. Mercincavage , Milton C. Weinstein , and Kenneth A. Freedberg Metrics Cited byAssessing the sensitivity and specificity of First Response HIV-1-2 test kit with whole blood and serum samples: a cross-sectional studyIndividual and Organizational Characteristics of Effective Frontline Practitioner Performance: A Study of Los Angeles County HIV Testing OrganizationsA systematic review and comparison of HIV contact tracing laws in CanadaFinancial impact of California's new law to increase HIV screening by mandating insurance coverageHIV/AIDS: The Only Thing Constant…Commentary: CDC Recommendations for Opt-Out Testing and Reactions to Unanticipated HIV DiagnosesPrinciples of Screening for Chronic Kidney DiseaseDifferences Between Proof-of-Concept Studies and Effective Implementation 5 December 2006Volume 145, Issue 11Page: 857-859KeywordsHIVHIV infectionsHIV preventionHealth surveysHematologic testsInfectious diseasesPregnancyProphylaxisViral transmission and infection ePublished: 5 December 2006 Issue Published: 5 December 2006 PDF downloadLoading ...