CDC report: Racial disparity in HIV/AIDS diagnoses remains high

In the United States, blacks are at greater risk of contracting HIV than other racial or ethnic groups.

Issue: May 2007

In the United States, a black woman is nearly 21 times as likely as a white woman to be diagnosed with HIV or AIDS, and a black man is nearly seven times as likely as a white man to be diagnosed with HIV or AIDS, according to recent CDC study results.

Statistics on HIV/AIDS rates in Washington, D.C., where more than 3% of the black adult population is living with AIDS, illustrate how racial disparity can reach epic proportions, experts said.

“The rate in Washington, D.C., is comparable to some of the lower prevalence African countries,” Robert Janssen, MD, director of the division of HIV/AIDS prevention for the CDC, told Infectious Disease News. Janssen and colleagues wrote the report, which appeared in the CDC’s Morbidity and Mortality Weekly Report.

The study offered statistical data of overwhelming racial disparity, according to the researchers.

Robert Janssen

Of the estimated 184,991 adult and adolescent HIV infections diagnosed from 2001 to 2005, more infections were diagnosed among blacks than among all other racial and ethnic populations combined.

Although black adults and adolescents accounted for 13% of the population in 33 U.S. states, more than 50% of newly-diagnosed HIV/AIDS cases from 2001 to 2005 were seen in black patients, according to the researchers.

Whites accounted for 72% of the overall population and 29.3% of diagnoses from 2001 to 2005. Hispanics accounted for 13% of the population and 18% of diagnoses during the same time frame.

The CDC report updated information through June 2006, in 33 states that had used confidential, name-based HIV/AIDS reporting since 2001. The largest age group for new diagnoses includes people aged 25 to 44 years old. Blacks accounted for 48% of the new diagnoses in this age group.

The disproportionate amount of HIV/AIDS on the black population is a concern CDC officials are trying to tackle through varying strategies. “We are recommending as part of our heightened national response that all African-Americans aged 13 to 64 get tested for HIV,” Janssen said.

Exposure increased

Although barriers to care are an obvious factor, experts are looking at sociological factors to gauge potential confounders to disparity in diagnoses.

“An interesting dilemma is that when you compare black men who have sex with men (MSM) and white MSM, the behavior is the same. So, why is the [HIV/AIDS] prevalence so much higher in the black population?” Janssen said.

Janssen theorized that social stigma-driven behavior is the start of a chain of responses that leads to increased HIV/AIDS exposure in the black U.S. population. Because the stigma of homosexuality in a culture and community decreases a person’s willingness to seek health services, exposure is increased.

Some studies indicate that black MSM may be more likely to choose other black MSM as partners, which also increases exposure. “Because of prevalence in the population, the chance of coming in contact with an HIV-infected partner is very high,” Janssen said.

Janssen said that young, black MSM are more likely to partner with older black men. Exposure is also increased by partnering with an individual in an age group of higher HIV/AIDS prevalence.

Black MSM are also less likely than white men to identify themselves as homosexual, which may lead to high transmission rates to black women. “What their female partners know is unclear,” Janssen said.

Statistics derived

Regarding black women, experts are unsure whether transmission of HIV is more likely to occur through sex with male IV drug users, sex with heterosexual men or sex with men who have sex with both men and women. “We don’t know that answer. We are trying to determine this because it is key in terms of how we target our prevention,” Janssen said. “We are recruiting a number of African-American women who have high-risk heterosexual behavior, and we are interviewing their partners.”

For the report, HIV and AIDS cases were analyzed together as HIV/AIDS to include HIV infection with or without progression to AIDS.

Transmission categories were MSM, IV drug use, MSM with IV drug use, high-risk heterosexual contact and other, which included blood transfusions and other risk factors not identified.

The number of HIV/AIDS diagnoses for each race and ethnic population by transmission category was estimated. For 2005, estimated diagnosis rates per population of 100,000 were calculated for each racial and ethnic population, and rate ratios were compared with those of whites vs. other populations. AIDS data included only people living with AIDS and was collected from 50 states and the District of Columbia. The data were based on information gathered until June 2006, and were limited to age, sex, race and risk factors.

Estimated HIV prevalence rates per population of 100,000 were calculated for the 33 states that have used confidential, name-based HIV reporting since at least 2001.

Name-based data collection is more accurate than coded collection because of duplications generated by people who have, for example, HIV diagnostics, a CD4 count and a later viral load report, which could be reported each time as a separate person in a given database, according to Janssen.

People in care may be reported to the heath department as many as 10 to 20 times in a year because they have more than one code, according to Janssen. Because of this, patients in care may be overrepresented and the people who are not accessing or seeking care do not exist as part of the epidemic, he said. The concern associated with attrition because of name-based collection is overshadowed by the need for representational numbers of HIV/AIDS cases.

“We need a data system that truthfully describes the epidemic because that’s what’s going to determine what services are needed for everybody,” Janssen said.

At present, all but three states have passed laws for collecting data by name.

Disparity revealed

Between 2001 and 2005, the black population represented the largest percentage of HIV/AIDS diagnoses in all age groups, as well as in the IV drug use and high-risk heterosexual transmission categories.

For MSM, HIV/AIDS diagnoses were greater in the white population (42.7%) than in the black (36.2%) or Hispanic populations (19%).

In 2005, the estimated annual HIV/AIDS diagnosis rate among black males was 127.6 per population of 100,000.

Among men by region, black men represented the largest population of people newly diagnosed with HIV/AIDS in the South (47.5%) and Northeast (46.1%). Among women, blacks represented the majority of HIV/AIDS diagnoses in the South (71.5%), Northeast (64.4%) and Midwest (63.5%) compared with other racial and ethnic populations.

The estimated HIV prevalence among blacks in 33 states in 2005 was 515 per population of 100,000, ranging from 109 in Alaska to 858 in New Jersey. The estimated AIDS prevalence in 50 states and Washington, D.C., per population of 100,000 ranged from 79 in Wyoming to 3,179 in Washington, D.C.

Age distribution varied by transmission category among black men and women. Most diagnoses of black men and adolescents were categorized as MSM (51.7%), followed by high-risk heterosexual contact (25.2%). Diagnoses among black women and adolescents were associated with high-risk sexual contact (80.4%), followed by IV drug use (18.2%).

Four strategies have been identified in response to the findings, according to Janssen.

Prevention measures include expanding prevention services, developing more effective intervention programs, increasing diagnosis opportunities and creating better community outreach to identify and change high-risk behavior. – by Kirsten H. Ellis

For more information:

Durant T, McDavid K, Hu X, et al. Racial/ethnic disparities in diagnoses of HIV/AIDS: 33 states, 2001-2005; MMWR. 2007;56:189-193.