October 26, 2007
Knowing the human immunodeficiency virus (HIV) status of tuberculosis (TB) patients is essential to optimal patient management. TB is an acquired immunodeficiency syndrome (AIDS)-defining opportunistic condition. Patients with both TB and HIV infection are five times more likely to die during anti-TB treatment than patients who are not HIV infected (CDC, unpublished data, 2003). HIV infection is the greatest known risk factor for progression from latent TB infection to TB disease (1). In the United States, after TB exposure and infection, HIV-infected persons who do not receive appropriate treatment progress to TB disease over 5 years at a rate 10 times greater than that for persons not infected with HIV (2,3). In 1989, CDC recommended that all TB patients be offered HIV testing (4) and, in 2006, called for routine HIV screening of all TB patients after the patient is notified that testing will be performed, unless the patient declines (opt-out screening) (5). In addition to enabling optimal patient management, knowing the HIV status (i.e., positive or negative) of TB patients helps public health agencies to identify HIV-infected contacts of TB patients. Highly active antiretroviral therapy (HAART) can reduce the progression to TB disease (6), TB relapse (7), and death (8). To assess reported HIV status of TB patients and selected characteristics of TB patients with HIV infection, CDC analyzed data from the U.S. National TB Surveillance System for the period 1993--2005. This report summarizes the results of that analysis, which indicated that 1) reporting of HIV status among TB patients increased from 35% in 1993 to 68% in 2003, 2) HIV status of 31% of TB patients was unknown in 2005, 3) 9% of TB patients were HIV positive in 2005, and 4) groups of TB patients at greater risk for HIV infection included injection-drug users (IDUs), noninjection-drug users (NIDUs), homeless persons, non-Hispanic blacks, correctional-facility inmates, and alcohol abusers. Increased promotion of routine HIV testing and rapid HIV tests (9) might increase acceptability of testing, which would allow health-care providers to know the HIV status of a greater percentage of TB patients and enable them to provide optimal care.
Data on reported HIV status were analyzed for the period 1993-2005 (updated through March 29, 2006) from the National TB Surveillance System for 49 states and the District of Columbia (DC).* This system contains data regarding confirmed cases of TB reported annually to CDC; the data are collected by state and local TB programs from interviews with patients, using a standardized surveillance case report form that includes HIV status. HIV status usually is assessed at the time of TB diagnosis but can be updated throughout the course of treatment for TB. Known HIV status was defined as either HIV positive or HIV negative. Unknown HIV status included the following categories: not offered testing, refused testing, tested with indeterminate results, tested but results unknown, and missing data. Mantel-Haenszel risk ratios (RRs), significant within 95% confidence intervals (CIs), were used to assess significant associations between variables.
Reported HIV status (i.e., positive or negative) among TB patients in the United States increased from 35% in 1993 to 68% in 2003, then leveled during 2004--2005 (Figure). Twenty-five states reported known HIV status for fewer than 75% of TB cases (Table 1). Twenty-six states and DC reported more than five TB patients with HIV-positive status, with the prevalence of positive results ranging from 5% to 32% (average: 13%; median: 11%) of TB patients having known HIV status.
Overall in 2005, a total of 7,689 (69%) of 11,193 TB patients in the United States had known HIV status and 3,504 (31%) had unknown HIV status (including 1,675 [15%] who were not offered testing and 827 [7%] who refused testing). Of the 7,689 with known status, a total of 1,034 (13%) were HIV positive and 6,655 (87%) were HIV negative. A significantly greater percentage (79%) of non-Hispanic black TB patients had known HIV status, compared with all other racial/ethnic groups combined (RR = 1.24, CI = 1.21--1.27) (Table 2). Non-Hispanic, U.S.-born black females were significantly less likely than black males to have known HIV status (RR = 0.91, CI = 0.87--0.95).
Groups of TB patients with rates of HIV infection significantly greater than the 9% rate for the United States overall included the following: IDUs (35%), NIDUs (27%), homeless persons (22%), non-Hispanic blacks (17%), correctional-facility inmates (16%), persons aged 25--44 years (16%), alcohol abusers (15%), males (11%), persons aged 45--64 years (11%), and U.S.-born persons (11%) (Table 2). A total of 652 (63%) of the 1,034 TB patients who were HIV positive were non-Hispanic blacks.
Among groups of patients having unknown HIV status, 33% of IDUs, 32% of NIDUs, 38% of homeless persons, 37% of inmates, and 37% of alcohol abusers were not offered HIV testing. In addition, 28% of Asians, 27% of patients aged 15--24 years and 45--64 years, 27% of non-Hispanic whites, and 26% of persons born outside the United States refused testing. Hispanics were significantly less likely to refuse HIV testing than non-Hispanics (RR = 0.64, CI = 0.55--0.75).
Reported by: S Marks, MPH, MA, E Magee, MPH, MS, V Robison, DDS, PhD, Div of Tuberculosis Elimination, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention, CDC.
Knowing the HIV status of TB patients is essential for optimal management of patient care, including selection of appropriate TB-treatment regimens and referral to and coordination of care for HIV infection. Once TB disease occurs, provider knowledge of HIV infection can help avoid TB relapse and mortality through increased vigilance and monitoring of TB therapy and providing access to HIV care and support services.
Knowing HIV status also helps public health programs identify HIV-infected contacts of TB patients, who are at increased risk for TB disease. Surveillance data enable CDC to track trends in TB/HIV accurately so that outbreaks can be identified and prevention measures targeted to areas where TB/HIV coinfection is most common.
However, despite CDC recommendations calling for routine HIV testing of all TB patients, the proportion of TB patients whose HIV status is unknown remained at approximately one third during 2003--2005. Data provided by the U.S. National TB Surveillance System are limited by incomplete reporting, which might result from 1) concerns regarding patient confidentiality or laws and regulations that might limit reporting of HIV status or 2) not offering HIV testing because of insufficient resources, lack of trained staff, or perceptions that patients are not at risk for HIV.
High rates of both HIV infection and TB disease among non-Hispanic blacks emphasize the need in this population to prevent, diagnose early, and provide access to care for both conditions. Substance abuse is a risk factor common to both TB and HIV infection, and homelessness and incarceration are two factors associated with both greater TB incidence and transmission of TB disease (10).
The findings in this report are subject to at least one limitation: the exclusion of data from California. In 2004, the latest year for which California reported AIDS-registry data to CDC, the state reported 123 TB patients who had AIDS, which amounted to approximately 10% of all known HIV/TB patients in the United States.
Improvements in HIV testing and reporting are needed. All TB patients should be offered HIV testing where feasible, especially IDUs, NIDUs, homeless persons, non-Hispanic blacks, correctional-facility inmates, and alcohol abusers. Implementation of the 2006 updated CDC HIV-testing recommendations, calling for routine HIV testing of all TB patients, and increased use of rapid HIV tests that can provide results in less than 20 minutes might increase acceptance of HIV testing. These improvements might increase the proportion of TB patients in the United States whose HIV status is known and who can thereby benefit from optimal care.
* California data were excluded because the state provides CDC only with the results of AIDS and TB registry matches, which likely underestimates TB/HIV prevalence. California does not report to CDC the numbers of TB patients whose HIV test status was negative or indeterminate, who refused testing, who were not offered testing, who were tested but with unknown results, or who were missing HIV data.