June 3, 2011
Although men who have sex with men (MSM) comprise an estimated 2% of the overall U.S. population aged ≥13 years,1 59% of persons with diagnoses of human immunodeficiency virus (HIV) infection in the United States in 2009 were MSM, including MSM who inject drugs.2 CDC recommends HIV testing at least annually for sexually active MSM to identify HIV infections and prevent ongoing transmission.3 Results of HIV testing conducted as part of the National HIV Behavioral Surveillance System (NHBS) in 21 cities indicated that 19% of MSM who were tested in 2008 were HIV-positive; of these, 44% were unaware that they were infected.4 To assess whether MSM were tested as recommended and whether more frequent testing might be indicated, CDC analyzed NHBS data for 2008. This report describes the results of that analysis, which indicated that, of 7,271 MSM interviewed and tested who did not report a previous positive HIV test, 61% had been tested for HIV infection during the past 12 months; among these, 7% had a new, positive HIV test result when tested as part of NHBS. Given the high prevalence of new HIV infection among MSM who had been tested during the past year, sexually active MSM might benefit from more frequent HIV testing (e.g., every 3 to 6 months).
NHBS is a behavioral surveillance system used to monitor HIV-related risk, testing, and prevention behaviors and HIV prevalence among populations at high risk for acquiring HIV.5 In 2008, NHBS staff members in 21 metropolitan statistical areas (MSAs) with high prevalence of acquired immunodeficiency syndrome (AIDS)* collected cross-sectional behavioral risk data and conducted HIV testing among MSM.4 MSM were sampled using venue-based sampling methods.6 NHBS staff members identified venues (e.g., bars, clubs, organizations, and street locations) and days and times when MSM frequented those venues.7 Venues and days/times were selected using a computerized random selection process each month for interviews and supplemented by up to three nonrandom events (e.g., Gay Pride events) per site per month. Staff members systematically approached men at each venue, intercepting potentially eligible men in the order in which they entered a designated "counting area."6 Men eligible to be interviewed were aged ≥18 years, residents of the MSAs, and able to complete the interview in English or Spanish. After participants gave informed consent, trained interviewers used a handheld computer to administer a standardized, anonymous questionnaire about sex, drug use, and HIV testing behaviors. All respondents were offered anonymous HIV testing, which was performed by collecting blood or oral specimens for either rapid testing at venues or laboratory-based testing. A nonreactive rapid test was considered a definitive negative result; a reactive (preliminary positive) rapid test result was considered a definitive positive result only when confirmed by Western blot or immunofluorescence assay. Incentives were offered for participating in the interview and HIV test.
This analysis excluded MSM who reported a previous positive HIV test. CDC determined the proportion of MSM who received an HIV test during the past 12 months and, of these, the proportion with a positive NHBS test result, stratifying by demographic and risk characteristics. Those testing positive were considered to be unaware of their infection. CDC sexually transmitted disease (STD) treatment guidelines recommend that MSM who have multiple or anonymous partners, have sex in conjunction with illicit drug use, use methamphetamine, or whose sex partners participate in these activities be screened for STDs and HIV more frequently (every 3 to 6 months) than those without such risk factors.8 To reflect these guidelines, MSM with high-risk behaviors were defined as those reporting at least one of the following: more than one male sex partner during the past 12 months, methamphetamine use during the past 12 months, sex in conjunction with illicit drug use at most recent sex, or a most recent male sex partner who definitely or probably had concurrent sex partners. CDC determined the proportion of HIV-infected men among MSM who did and did not report high-risk behaviors.
A multivariable Poisson model was used to create unadjusted and adjusted prevalence ratios to determine factors associated with being HIV-infected.9 The adjusted model controlled for various factors: race/ethnicity, age, annual household income, education, health insurance status, time since most recent HIV test, unprotected anal sex, and high-risk behaviors.
Of 28,468 men approached, 12,325 were screened for participation at 626 venues. Of men screened, 11,074 (90%) were eligible for the survey. Men who were surveyed were excluded from analysis if they did not complete both the survey (n = 396 [4%]) and the HIV test (n = 1,535 [14%]), did not report sex with a man during the preceding 12 months (n = 1,744 [16%]), had an indeterminate HIV test result (n = 85 [0.8%]), or reported being HIV-positive (n = 1,214 [11%]). These reasons were not mutually exclusive. Of eligible men, 7,271 (66%) were included in this analysis.
Of men included in this report, 44% were white, 25% were Hispanic, and 23% were black. Mean age was 34 years (range: 18-85 years); 62% had less than a college education, 29% reported an annual household income <$20,000, and 34% had no health insurance (Table 1).
Among the 7,271 MSM, 680 (9%) were HIV-infected. Of these, 16% had never been tested for HIV, and 29% had been tested during the past 6 months (Figure).
Among the 7,271 MSM, 4,453 (61%) had tested for HIV infection during the past 12 months and did not receive a positive HIV test result. The proportion tested was higher among MSM in younger age groups and those with higher levels of education and income but did not vary by race/ethnicity (Table 1). Among 5,864 (81%) MSM with high-risk behaviors, 44% had been tested for HIV infection during the past 6 months.
Among the 4,453 MSM who had not received a diagnosis of HIV infection previously and were tested for HIV during the past 12 months, 7% (15% of blacks, 7% of Hispanics, and 3% of whites) were found to be HIV-infected when tested by NHBS (Table 2). Of 3,672 MSM with high-risk behaviors who were tested for HIV in the past 12 months and did not receive a positive HIV test result, 7% were HIV-infected when tested by NHBS, compared with 8% of those who did not report any high-risk behaviors. Prevalence of HIV infection among these two groups remained similar after adjusting for time since most recent HIV test. After adjusting for risk and testing behaviors, substantial and significant differences between black, Hispanic, and white MSM persisted (Table 2).
Reported by: Alexandra M. Oster, M.D., Isa W. Miles, Sc.D., Binh C. Le, M.D., Elizabeth A. DiNenno, Ph.D., Ryan E. Wiegand, M.S., James D. Heffelfinger, M.D., Richard Wolitski, Ph.D., Div of HIV/AIDS Prevention, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention, CDC. Corresponding contributor: Alexandra M. Oster, CDC, email@example.com, 404-639-6141.
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