Men who have sex with men (MSM), particularly MSM of color, are disproportionally affected by HIV and primary and secondary syphilis in the United States. Although MSM comprise approximately 2%–4% of the population,1 53% of all new HIV infections in 2006 were among MSM.2 In 2004, among men aged 13–19 years, the HIV diagnosis rate for black MSM was estimated to be 19.6 times the diagnosis rate for white MSM.3 In 2008, MSM accounted for 62% of all primary and secondary syphilis cases,4 and among men aged 15–19 years in 27 states, the rate for black MSM was estimated to be 18.4 times the rate for white MSM.5 Additionally, trend data suggest that HIV and syphilis infections are increasing among young MSM. From 2001 to 2006, reported HIV diagnoses among black MSM aged 13–24 years in 33 states increased 93%.6 From 2005 to 2008, rates of primary and secondary syphilis among black MSM aged 15–19 years in 27 states increased 180%.5
These reports provide a picture of national trends in HIV and syphilis; however, national trends in diagnoses are influenced by large numbers from urban population centers, many of which have documented disparities by both race/ethnicity and by mode of transmission.7,8 The majority of HIV diagnoses occur in large urban areas9 and trends may be driven by a few cities. In 2008, 2 metropolitan statistical areas (MSAs) accounted for 20% of all primary and secondary syphilis cases4 and 3 MSAs accounted for 20% of all reported HIV dignoses.9 Documentation of recent increases in HIV among young black MSM in areas with historically low prevalence, such as Jackson, Mississippi10 and Milwaukee, Wisconsin,11 suggest that increases may be occurring in other areas of the country. In this analysis, we investigated if increases in HIV among young MSM and syphilis among young men are widespread or confined to a few large urban areas.
MSAs are counties or groups of counties that have at least 1 urbanized area with a population of at least 50,000 persons. Some MSAs with a population larger than 2.5 million are further divided into MSA divisions.12 We selected all MSAs and MSA divisions (collectively called “areas” in this report) with a population greater than 500,000 and at least 500 black men aged 13–24 years, based on US census estimates for 2004.13 As we wanted to examine temporal trends, we limited our analysis to areas in 34 states that had mature HIV reporting systems as of 2004 (Alabama, Alaska, Arizona, Arkansas, Colorado, Florida, Georgia, Idaho, Indiana, Iowa, Kansas, Louisiana, Michigan, Minnesota, Mississippi, Missouri, Nebraska, Nevada, New Jersey, New Mexico, New York, North Carolina, North Dakota, Ohio, Oklahoma, South Carolina, South Dakota, Tennessee, Texas, Utah, Virginia, West Virginia, Wisconsin, and Wyoming). A reporting system was considered mature if the area had confidential name-based reporting of HIV infection for at least 4 years. If the area crossed state lines and 1 state had a mature reporting system and 1 did not, only the portion of the area with a mature reporting system was included, provided the area portion continued to meet the initial inclusion criteria (population greater than 500,000 and at least 500 black men aged 13–24 years in 2004). Primary and secondary syphilis have been notifiable diseases in all included areas since the 1940s.14
We used the most recently available data from the Centers for Disease Control and Prevention's (CDC's) National HIV Surveillance System to determine temporal trends in diagnosed HIV infection reported as of June 30, 2009. For each area, we obtained aggregate annual counts of reported diagnoses of HIV (regardless of stage of disease at diagnosis) among men who were identified as MSM with or without a history of intravenous drug use (collectively categorized as MSM for this report). Diagnosis counts were adjusted for reporting delays, and multiple imputations were used to assign risk factors for cases with missing risk factor information.15–17 Data were stratified by age and race/ethnicity.
We used aggregate data from the national electronic telecommunication system for surveillance to examine temporal trends in syphilis diagnoses. For each area, we obtained annual counts of reported diagnoses of primary and secondary syphilis among men (not MSM), as gender of sex partner was not reported on syphilis case reports until 2005 and is not available for all male cases.4 Data were stratified by age and race/ethnicity.
To visually examine trends in HIV and syphilis, we plotted the number of diagnoses reported by age and race/ethnicity from 2004 to 2008. To determine the proportion of areas with increases in HIV among MSM or increases in primary and secondary syphilis among men, we compared the average number of diagnoses in 2004/2005 to the average number of diagnoses in 2007/2008, across strata defined by age at diagnosis (13–24 years, 25–29 years, ≥30 years) and race/ethnicity (non-Hispanic black, non-Hispanic white, and Hispanic). As there are no population estimates of the number of MSM by age, race/ethnicity, and geographic location, we examined changes in the number of diagnoses. An increase was defined as any difference in diagnoses >0. Using this crude cut-off, changes in diagnoses due to chance would cause some areas to look like they had an increase and others to look like they had a decrease. We examined the distribution of the direction of changes over all the areas (to see if most are moving in the same direction), recognizing that in any single area a change may be due to chance.
To estimate the magnitude of the change in reported diagnoses for each area, we calculated the average percentage change. For these percentage change calculations, areas which reported zero diagnoses in 2004/2005 could not be included, unless they reported zero cases for all 4 years. To identify concurrent patterns of reported diagnoses of HIV and syphilis, we graphically displayed the percentage of areas with increases in both diagnoses within age-by-race/ethnicity groups. For those analyses, areas reporting zero diagnoses of either disease in 2004/2005 or 2007/2008, or no change in cases, were removed. To investigate differences by population size, we conducted all analyses stratified by area size (500,000–999,999 persons, 1 million to 2.49 million persons, and ≥2.5 million persons).
Seventy-three areas met our inclusion criteria. Included areas represent 65% (73 of 113) of all MSAs and MSA divisions in the United States with a population more than 500,000 in 2004. These areas were stratified by population size in 2008: 500,000–999,999 (n = 29), 1 million to 2.49 million (n = 33), and ≥2.5 million (n = 11). The areas are located in 29 of the 34 states with mature HIV reporting systems, as Alaska, Idaho, North Dakota, South Dakota, and Wyoming had mature systems, but did not have MSAs which met the inclusion criteria. Included areas are primarily in the South (n = 37) and the Midwest (n = 19) with the remainder split between the Northeast (n = 10) and the West (n = 7). In 2008, included areas accounted for 74.7% (17,639 of 23,610) of all HIV diagnoses reported among MSM and 60.5% (6,900 of 11,398) of all primary and secondary syphilis cases reported among men.
All areas reported at least 1 HIV diagnosis among MSM and at least 1 syphilis diagnosis among men during 2004 to 2008, although some areas did not report any diagnoses among specific age and race/ethnicity categories. The total number of reported HIV diagnoses among MSM in all 73 areas increased 10.5% from 2004 to 2008 (from 15,783 cases to 17,639 cases); the total number of syphilis diagnoses among men increased 88.8% (from 3,654 cases to 6,900 cases). The largest increases in HIV diagnoses were among black MSM aged 13–24 years (Figure 1). Diagnoses remained relatively stable for MSM aged ≥30 years of all race/ethnicities. Diagnoses of syphilis increased for all ages by race/ethnicity groups and within each race/ethnicity group increases were generally largest among men aged <30 years.
Comparing the average number of HIV diagnoses in 2004/2005 with 2007/2008, increases occurred among black MSM aged 13–24 years in 85% of the areas in this study (n = 62) (Figure 2). Increases were observed in more areas for black MSM aged 13–24 years than Hispanic or white MSM of the same age (62% and 58% of areas, respectively) or older MSM of any race/ethnicity. This pattern was similar for areas of all sizes, with diagnoses among black MSM increasing in 21 of 29 (72%) of areas with a population between 500,000 and 999,999; in 30 of 33 (91%) of areas with a population between 1 million and 2.49 million; and in 11 (100%) of areas with a population ≥2.5 million (see Figures, Supplemental Digital Content 1, http://links.lww.com/QAI/A207). Compared with all other race/ethnicities by age group, the average percentage change in the number of HIV diagnoses was highest among black MSM aged 13–24 years [68.7%, interquartile range (IQR): 25.0–103.1] (Table 1). Across area size strata, among MSM aged 13–24 years, average percentage changes in diagnoses were consistently highest among black MSM (see Tables, Supplemental Digital Content 2, http://links.lww.com/QAI/A208).
Comparing the average number of primary and secondary syphilis diagnoses in 2004/2005 with 2007/2008, increases occurred among black men aged 13–24 years in 70% of the areas in this study (n = 51) (Figure 2). Just as for HIV diagnoses, this percentage was higher for the youngest group of black men than for any other age by race/ethnicity groups, with many areas reporting no diagnoses among Hispanic men in the 4 years being compared. The average percentage change was highest among black men aged 13–24 years (203.5%, IQR: 0.0–197.2) (Table 1). This pattern of the youngest group of black men having the highest average percentage change and the highest percentage of areas with increases in diagnoses was similar across area size strata with one exception; in areas with population of 500,000 to 999,000, increases in diagnoses were observed in more areas for white men older than 30 years (see Figures, Supplemental Digital Content 1, http://links.lww.com/QAI/A207 and Tables, Supplemental Digital Content 2, http://links.lww.com/QAI/A208). The largest increase in syphilis diagnoses among black men aged 13–24 years was in areas with a population of ≥2.5 million (average percentage change: 368.6%, IQR: 66.7–350.0) (see Table 1C, Supplemental Digital Content 2, http://links.lww.com/QAI/A208).
The majority of areas (79%, 46 of 58) had increases in both HIV and syphilis in black men aged 13–24 years (Figure 3). Concurrent increases in diagnoses of HIV and syphilis were also observed for Hispanic men aged 13–24 years (73% of areas, 22 of 30). Half of the areas in this study (25 of 50) had concurrent increases for white men aged 13–24 years. Concurrent increases in HIV and syphilis diagnoses were more common among men aged <30 years compared with men aged ≥30 years, except among white men.
During 2004 to 2008, diagnoses of both HIV in MSM and primary and secondary syphilis in males increased among black men aged 13–24 years in the majority of areas which met our inclusion criteria, regardless of area size. These findings document that increases in HIV and syphilis diagnoses among young black men are not limited to a few large areas but are widespread among areas with different population sizes.
Changes in testing programs may account for the increase in diagnoses of HIV and syphilis. In 2006, CDC recommended an opt-out screening policy for HIV infection in health care settings and suggested that all persons at high risk be screened annually.18 In 2007, CDC began a $36 million initiative to expand testing to populations disproportionately affected by HIV, primarily African Americans,19 and some cities have reported increases in the number of African Americans tested in publicly funded test sites.20,11 Additionally, in 2006, CDC recommended that all sexually active MSM be screened at least annually for common sexually transmitted infections (STIs), including syphilis and HIV.21 Testing expansions likely increased the number of diagnoses among young MSM with previously unidentified prevalent infections and increased the frequency of testing for some men, which might have affected temporal trends in diagnoses. If areas expanded or targeted their HIV testing programs to young black MSM during the 5-year period, reported diagnoses may have increased even if transmission patterns remained stable.
Increases in transmission may also explain the observed increases in diagnoses of HIV and syphilis. HIV testing history or use of tests designed to detect acute or recent HIV infection are needed to determine if an HIV diagnosis represents an incident infection. However, for young MSM, who presumably have had a shorter time to be sexually exposed to HIV, an HIV diagnosis may represent a relatively recent infection. The observed increased in HIV diagnoses among MSM aged 13–24 years suggests an increase in transmission. Additionally, by definition, primary and secondary syphilis diagnoses are incident infections. Thus, a syphilis diagnoses can serve as a “real-time” marker of unprotected sexual intercourse that may result in transmission of syphilis or HIV. The observed increase in syphilis diagnoses implies some young men had recent sexual behaviors (or sexual activity within at-risk networks) that placed them at risk for both syphilis and HIV.
Regardless of the underlying cause of increasing diagnoses, young black MSM have disproportionately high rates of HIV diagnosis, and rates are increasing among young MSM of all race/ethnicities, highlighting the need for prevention efforts which address the behavioral and structural factors that place these men at risk. Young MSM experience discrimination, stigma, and violence, which may lead to maladaptive coping strategies, such as substance use and unprotected sex.22 These behaviors may increase their risk for HIV and syphilis. Additionally, many young MSM are disconnected from traditional prevention education targeting youth. In a recent qualitative study of young MSM in Los Angeles (n = 57), respondents reported that same-sex sexuality discussions were “practically nonexistent” in schools and at home.23 As a consequence, young MSM reported being unprepared at their first sexual encounter, such as being ill equipped to negotiate safer sex or not knowing to use lubricant to reduce tearing and bleeding during anal sex.
Our findings describe the increasing racial disparities in HIV and syphilis diagnoses among young MSM, as documented in surveillance data. The underlying contributors to disparities are multifaceted and are likely influenced by social and contextual factors. Individual-level risk behaviors that transmit HIV and syphilis are not more prevalent among young black MSM when compared with young white MSM,24 which suggests that social factors, such as sexual network configurations (eg, sex with black and older partners) may contribute to disparities in infection.24,25 Young black MSM are also more likely to have undiagnosed HIV infections compared with young white MSM,26 which may result from community-level stigma that prevents some high-risk MSM of color from being tested for HIV and other STIs.27 The high prevalence of undiagnosed infection likely facilitates HIV transmission within sexual networks of young black MSM.28 Additionally, young black and Latino MSM are more likely than young white MSM to experience childhood sexual abuse, a predictor of HIV seroconversion.25 Thus, prevention efforts must extend beyond individual-level interventions and address social factors influencing HIV and syphilis transmission among young MSM. In the absence of such interventions, disease transmission will likely continue to increase among young black MSM.
The concurrent syphilis and HIV epidemics among young black MSM underscore the need for HIV and sexually transmitted disease program collaboration and service integration. This strategy can maximize the benefit of HIV and STI prevention services.29 Young MSM who are diagnosed with syphilis or other STIs should be offered HIV counseling and testing, and men diagnosed with HIV should be tested and treated for other STIs. Use of HIV and STI data together can identify men who might benefit most from prevention services. For example, MSM who have an STI, but are HIV-negative, could be offered participation in behavioral interventions such as “Many Men, Many Voices or D-Up: Defend Yourself!” (a black MSM adaptation of the Popular Opinion Leader intervention), which have been shown to decrease the frequency of unprotected anal intercourse, increase the likelihood of condom use and/or reduce the number of sexual partners among black MSM.30,31 HIV-positive MSM who contract an STI, a marker of recent risk behavior, could be offered partner services, risk reduction counseling, or offered participation in behavior change interventions such as “Healthy Relationships”, a small-group intervention for men and women living with HIV, which has shown to reduce unprotected sex in serodiscordant relationships.32
Collaboration and service integration among HIV prevention, testing, and care programs is also needed. Ensuring that young MSM who are diagnosed with HIV are linked to timely care is both a primary and secondary prevention strategy33 and increasing access to HIV care is one of the primary objectives of the National AIDS Strategy.34 Barriers to young MSM accessing HIV care likely include insufficient financial resources, perceptions about invulnerability, perceived stigma, and transportation issues.35,36 MSM of color may face additional barriers such as provider discrimination and mistrust of the medical system.37 Innovative initiatives to facilitate timely entry into care are needed to both improve health outcomes among young MSM and prevent ongoing transmission.
This analysis is subject to several limitations. Only areas with mature HIV reporting systems were included in this analysis and the findings may not be representative of trends in areas that were not included. Areas were selected based upon population estimates for black men aged 13–24 years and, therefore, included some areas with small Hispanic populations and excluded some areas with large Hispanic populations. Only infections identified and reported to a state or local health department were included in this analysis and likely underrepresented the true number of infections. Additionally, statistical adjustments for reporting delays and cases reported without risk information were used to estimate HIV diagnoses, and their accuracy is dependent on the validity of the assumptions used in adjustment.17 It is possible that changes in population size over the period would affect the number of reported cases even if rates remained stable. We report average percentage change over time; a large change in this relative measure may correspond to a small absolute change in diagnoses. Finally, although our primary population of interest was MSM, risk factor information for syphilis diagnoses was not available for all of the selected areas over the entire period, and diagnoses among males were used as a proxy. In 2008, 62% of male primary and secondary syphilis cases with available risk factor information were identified as MSM.4 Additionally, the number of syphilis infections increased among women during the period,4 and it is likely that the number of cases among men who have sex with women also increased. Consequently, syphilis data presented in this analysis overestimate the number of cases of syphilis among MSM and may not accurately reflect trends in MSM.
Many of the selected areas reported few diagnoses of both HIV and syphilis within each age-race/ethnicity stratum, which makes interpreting small changes in diagnoses over time difficult. To increase stability of estimates, we combined 2 years of data to make temporal comparisons. We did not use statistical tests to quantify changes in diagnoses as our hypothesis was not whether chance accounted for the change in a single area. Instead, we used a crude cut-off point of any rise in diagnoses as an “increase” and any drop in diagnoses as a “decrease” to examine patterns of change across all areas.
This analysis provides a broad view of the HIV and syphilis epidemics in young MSM and highlights growing disparities in the United States. Reasons underlying increases in diagnoses are unclear; however, it is apparent that infections among young MSM are unacceptably high. Examining these data in light of other data sources can help inform strategic planning and resource allocation.38 As a next step, individual program areas should use their local data to guide the choice of appropriate interventions, including examining patterns of comorbidity of HIV and other STIs to identify populations which could be targeted for prevention programs. Documented increases highlight the need for continued prevention efforts for young MSM, particularly young black MSM. School-based comprehensive sexual health education that is inclusive of discussions on same-sex sexuality is needed. Young MSM may also benefit from constructive discussions of their sexuality within their families and during medical encounters, as these may equip them with the skill necessary to avoid HIV and STI infection the first sexual encounter. Additionally, efforts should be made to ensure seamless and timely linkage to care for young MSM diagnosed with HIV. As the underlying causes of the epidemic are likely multifactorial, combining multiple strategies may prove most beneficial in improving the sexual health of this increasingly vulnerable population.
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HIV; men who have sex with men; syphilis
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