Conference on Retroviruses and Opportunistic Infections (CROI)
Select CDC Studies of Interest
CDC scientists will be presenting more than 40 abstracts at CROI 2015. Several studies that may be of particular interest to reporters are briefly summarized below.
All research is embargoed until the end of the oral abstract or poster session where it is being presented.
HIV Stages of Care
Ensuring people with HIV are diagnosed and remain in care is key to controlling the nation’s HIV epidemic. When used consistently, antiretroviral medication can keep HIV controlled at very low levels in the body (known as viral suppression), allowing people with HIV to live longer, healthier lives and reducing the likelihood they will transmit HIV to others. In fact, recent research shows the vast majority of new infections are transmitted by those who are not yet benefitting from treatment (either because they don’t know they are infected or because they are not receiving care).
Two CDC studies provide additional insight into progress and disparities in HIV testing, care, and treatment.
- Late HIV diagnosis in metropolitan areas of the United States and Puerto Rico (Poster Abstract, Session P-W1)
Overview: Timely diagnosis is essential for linking people living with HIV to effective care and treatment. This analysis shows that the proportion of HIV cases diagnosed late declined substantially from 2003 to 2012. Late diagnosis is defined as people who are diagnosed with AIDS within three months of their initial HIV diagnosis. Still, in 2012, about one-quarter of diagnoses came after late-stage disease had already developed. Additionally, the data show disparities by race/ethnicity and transmission risk group in some areas.
Using National HIV Surveillance System (NHSS) data, the study examined diagnosis trends by Metropolitan Statistical Area (MSA), finding that:
Authors conclude that expanded testing initiatives appear to be having an impact, particularly in the urban areas and MSM populations where they are most heavily focused. However, the study suggests a need to tailor efforts by MSA to improve diagnosis among all populations at risk.
- From 2003 to 2012, late diagnoses decreased overall (from 33 to 24 percent).
- Diagnoses declined the most in large MSAs (areas with populations of 500,000 or more), from 32 percent to 23 percent; the decline was from 34 to 26 percent in smaller MSAs (population 50,000 to 499,999) and from 34 to 30 percent in non-metropolitan areas.
- Racial disparities varied across MSAs. In some large MSAs, including Miami, FL; New York, NY; and Washington, DC, the proportion diagnosed late was higher among African Americans compared to whites, but in other MSAs (including Dallas, TX and Phoenix, AZ) the proportion diagnosed late was lower among African Americans compared to whites.
- In the majority of large MSAs, the proportion diagnosed late was lower among persons with infection attributed to male-to-male sexual contact compared to persons with infection attributed to injection drug use or heterosexual contact.
- CDC Contact: Irene Hall, CDC
- Location: Poster Hall, 999
- DATE/TIME: Tuesday, February 24, 2:30 PM PT
- Time Above 1500 Copies/ml: A Viral-Load Measure for Assessing Transmission Risk of HIV-Positive Patients in Care (Oral Abstract, Session 0-8)
Overview: This analysis suggests that even patients who received HIV care spent significant periods of time with viral loads high enough to increase their risk of transmitting the virus to others, with younger patients and African American patients faring worst in this regard.
Using data from 14,532 patients visiting six clinics from April 2009 through March 2013, researchers measured the amount of person-time (PT) individuals in HIV care spent above a viral load (VL) of 1500 copies/ml (a threshold that increases risk for transmission), finding that:
This study shows, using a novel method, that substantial risk of HIV transmission occurs in many patients who received HIV care. This finding underscores the importance of ensuring all people living with HIV receive the support they need to adhere to their HIV treatment regimens.
- Overall, HIV VL exceeded the threshold during 23 percent (or approximately one-quarter) of patients’ observation time (average of 84 days per person, per year).
- More than half (54 percent) had at least one VL test above the threshold.
- Time spent above the threshold was highest among younger patients (32 percent of observation time for those aged 16 to 39 vs. 16 percent for those 50+) and African Americans (26 percent of observation time among black patients vs. 16 percent among whites).
- CDC Contact: Lytt Gardner, CDC
- Location: Room 6E
- DATE/TIME: Wednesday, February 25, 11:30 AM PT
African American Women: Care and Treatment
CDC data has shown encouraging signs of a decrease in new HIV infections among black women in recent years. However, African American women continue to be far more affected by HIV than women of any other race or ethnicity, with a rate of new infection 20 times that of white women and nearly five times that of Hispanic women. Additionally, black women account for the majority (64 percent) of new HIV infections among women overall.
The following CDC study describes racial and other disparities in HIV care and treatment among women, including African American women.
- Care and viral suppression among women, 18 US jurisdictions (Oral Abstract, Session 0-8)
Overview: This study finds that viral suppression among women diagnosed with HIV is low, with young women and black women among the least likely to achieve viral suppression. Only half of women received ongoing HIV care.
Using National HIV Surveillance System (NHSS) data reported from 18 U.S. areas, researchers assessed differences in HIV care and viral suppression among women by age and race/ethnicity, finding:
With fewer than half of American women diagnosed with HIV achieving viral suppression, the analysis underscores the need to improve care and treatment for all women, with a particular focus on younger women, and African American women.
- Of women newly diagnosed with HIV in 2012, 83 percent were linked to care within three months of diagnosis.
- Retention in care (defined as having at least two CD4 or viral load tests at least 3 months apart in 2011) varied by age and race/ethnicity; overall, just over half of women (52 percent) diagnosed and living with HIV in 2011 received ongoing HIV care.
- Overall, only 44 percent of women diagnosed and living with HIV in 2011 had a suppressed viral load.
- Viral suppression was lower among blacks (42 percent) than among most other races/ethnicities (49 percent among Latinos, 48 percent among Asians, 47 percent among whites). Viral suppression was lowest among American Indians/Alaska Natives (30 percent), who accounted for less than one percent of the females with HIV in these jurisdictions.
- Viral suppression was higher among women ≥ 55 years (53 percent) compared with those aged 13-24 (33 percent), 25-34 (36 percent), 35-44 (42 percent), and 45-54 (48 percent).
- CDC Contact: Ndidi Nwangwu-Ike, CDC
- Location: Room 6E
- DATE/TIME: Wednesday, February 25, 11:15 AM PT
MSM: HIV Burden and Risk Behaviors
Men who have sex with men (MSM) remain the risk group most severely affected by HIV in the United States, accounting for approximately two-thirds of new infections each year. Young black MSM in particular comprise more new infections than any other subgroup by race/ethnicity, age, and sex. Two CDC studies investigate trends and racial disparities in HIV among MSM.
- Increases in HIV diagnoses among MSM in Metropolitan Statistical Areas, United States(Poster Abstract, Session P-W5)
Overview: This study finds that HIV diagnosis rates in the U.S. declined overall from 2003 to 2012. However, the number of HIV diagnoses from 2008 to 2012 increased in some MSAs, especially among MSM and among young MSM
Using data from the National HIV Surveillance System (NHSS), researchers assessed changes in the annual number and rate of HIV diagnoses in 105 large MSAs (areas with populations of 500,000 or more), finding that:
The authors note that the results are consistent with other data, including past estimates on new HIV infections, finding troubling signs of recent increasing infections among young gay and bisexual men. The wide variation in overall diagnosis rates by geography points to a need for tailored, targeted prevention efforts.
- Overall, the HIV diagnosis rate in the MSAs decreased by an average of 3.7 percent per year. Significant decreases were observed in more than half (64 percent) of the MSAs assessed.
- However, among MSM the number of diagnoses in the MSAs increased from 2003 to 2007 by a total of 10.8 percent; it then leveled off and subsequently declined by 2.2 percent from 2008 to 2012.
- The number of diagnoses among MSM in the later period significantly increased in 10 MSAs, decreased in 9 MSAs, and remained unchanged in all others.
- Among young MSM 13-24 years of age, the number of diagnoses in the MSAs continued to increase (by 15 percent overall) from 2008 to 2012.
- The number of diagnoses among older MSM 55-64 and 65 years of age remained unchanged from 2008 to 2012.
- CDC Contact: Lorena Espinoza, CDC
- Location: Poster Hall, 1040
- DATE/TIME: Thursday, February 26, 2:30 PM PT
- Disparities in HIV by race and age among men who have sex with men, 20 US cities(Poster Abstract, Session P-W5)
Overview: This study shows that racial disparities in HIV prevalence and awareness of infection are particularly stark among young MSM, suggesting that African American MSM are being infected at younger ages compared to MSM of other racial/ethnic groups. Additionally, racial disparities exist – and are increasing – among MSM in nearly every age group, despite similar levels of condom use.
Using National HIV Behavioral Surveillance (NHBS) data from 20 U.S. cities, CDC researchers assessed changes in HIV prevalence, awareness of infection, and risk behavior among MSM, by age and race, from 2008 to 2011, finding that:
These data suggest that prevention efforts focused on African American MSM should particularly address the needs of those under the age of 25.
- Among black MSM, 30 percent were HIV-infected overall, and 20 percent among those aged 18-24 (compared to 14 and 4 percent among white MSM, respectively).
- In all age groups younger than 40 years, black MSM were significantly more likely to be HIV-positive compared to all other racial/ethnic groups. Disparities in HIV prevalence between black and white MSM were greatest among the youngest MSM, and increased between 2008 and 2011.
- Black MSM were less likely to be aware of their infection than their white counterparts (54 vs. 86 percent overall).
- Black MSM did not report higher levels of sex without a condom, overall or specifically with discordant partners or partners of unknown HIV status.
- CDC Contact: Cyprian Wejnert, CDC
- Location: Poster Hall, 1041
- DATE/TIME: Thursday, February 26, 2:30 PM PT