March 11, 2008
Two CDC studies of STD screening among men who have sex with men (MSM) found that testing rates are significantly lower than recommended in public health guidelines. For sexually active MSM, CDC recommends annual HIV and syphilis blood testing, annual chlamydia testing, as well as annual gonorrhea testing at all anatomic sites of exposure (pharyngeal, urethral, and rectal) - with more frequent testing for MSM who are engaged in high-risk behavior.
A study led by CDC's Eric Tai found that fewer than half of HIV-negative MSM report annual syphilis and gonorrhea testing. These investigators identified a range of factors associated with an increased likelihood of an individual being tested.
In the largest study of its kind to date, the researchers analyzed data from more than 10,000 HIV-negative MSM (n=10,030) in 15 cities collected by the National HIV Behavioral Surveillance System from 2003 to 2005. They found that, within the previous year, just 39 percent reported having been tested for syphilis and 36 percent reported having been tested for gonorrhea.
The study identified four factors that were associated with having been tested for syphilis or gonorrhea:
In order to increase annual STD testing among sexually active MSM, as recommended in CDC's STD Treatment Guidelines, the researchers recommend that health care providers routinely assess the risks of STDs among male patients through inquiries about sexual activity.
A study led by CDC's Karen Hoover found that HIV-infected MSM are infrequently tested for STDs. Because HIV infection increases the risk of contracting other STDs, and because having an STD increases the risk of HIV transmission, diagnosing and treating STDs is critical -- both for the health of HIV-infected individuals and for HIV prevention efforts. CDC recommends at least annual screening for STDs among asymptomatic HIV-infected MSM.
The study examined data from HIV-infected MSM receiving care at eight HIV clinics in six U.S. cities (Chicago, New York, Miami, Atlanta, San Francisco, and Los Angeles) from 2004 through 2006. The study included three components: a survey that asked providers how often they questioned patients about consistent condom use and how often they tested asymptomatic patients for STDs if they reported unprotected sex; a survey that asked patients if they had been tested for an STD in the past year when asymptomatic; and a review of medical records from patient visits to determine actual STD testing rates.
The survey of 128 providers found that almost all (96%) reported that they asked (80% always and 16% sometimes) their HIV-infected MSM patients about condom use. Among these providers, 89 percent reported that they would test (73% always and 16% sometimes) for syphilis in asymptomatic HIV-infected MSM reporting unprotected sex, while 88 percent said they would test (49% always and 39% sometimes) for gonorrhea, and 84 percent reported they would test (45% always and 39% sometimes) for chlamydia.
The patient survey results differed from provider responses. Less than half (49%) of 507 asymptomatic patients reported being offered a syphilis test within the last year, and even fewer reported being offered a gonorrhea (35%) or chlamydia (32%) test.
To estimate actual, annual STD screening rates, the researchers also examined patient medical records for each year of the study. As illustrated in the chart below, a preliminary analysis of medical records from 1,506 patients in 2005 (most recent data) found that although annual syphilis screening was relatively common, annual chlamydia and gonorrhea screening of asymptomatic patients was done infrequently.
Researchers also investigated whether there were differences in screening by race. About 59 percent of the patient medical records reviewed were from minority populations. As the chart below indicates, while similar proportions of black and white MSM were tested for chlamydia and gonorrhea, fewer Hispanic patients were tested. The authors note that STD screening of patients in all racial and ethnic populations was less frequent than recommended by guidelines.
Percent of asymptomatic HIV-infected MSM screened for syphilis, chlamydia, and gonorrhea in 2005*
The researchers hypothesize that although results from the provider survey indicate that providers understand the importance of STD screening for HIV-infected patients, actual screening rates for chlamydia and gonorrhea may be low because there are multiple barriers that prevent physicians from following the guidelines. Barriers may include too few laboratories that perform pharyngeal and rectal testing, provider discomfort with detailed sexual risk assessment, and competing counseling and testing priorities during a brief office visit. The researchers suggest that the development of provider-focused interventions to facilitate testing could improve STD screening rates in HIV-infected MSM, as would better dissemination of screening guidelines.
Oral Abstract D5a -- Self-Reported Syphilis and Gonorrhea Testing Among Men Who Have Sex With Men (MSM) in the United States, National HIV Behavioral Surveillance System, 2003-2005; and Poster Abstract P143 -- STD Testing of HIV-Infected MSM at Eight U.S. Clinics. In: 2008 National STD Prevention Conference, Chicago, Ill., March 10-13, 2008.