New research was presented at CROI 2016, the annual Conference on Retroviruses and Opportunistic Infections, from February 22 to 25 in Boston. The features below highlight some of the studies that emerged from the conference.
New Lifetime HIV Risk Estimates
The Particulars: In 2004, the CDC estimated that the lifetime risk of being diagnosed with HIV was 1.29%, or one in every 78 Americans. CDC researchers have used HIV diagnosis, mortality, and census population data to determine current lifetime and age-conditional risk across the country by various subgroups and by state.
Data Breakdown: A study team from the CDC estimated the lifetime risk of being diagnosed with HIV in the United States to now be 1.01%, or one in every 99 Americans. The risk of acquiring the virus ranged drastically among various subgroups:
- Men (one in 62) vs women (one in 221).
- African American men (one in 20) vs women (one in 48).
- Hispanic and Latino men (one in 48) vs women (one in 227).
- Caucasian men (one in 132) vs women (one in 880).
- African American men who have sex with men (MSM; one in two) vs Hispanic MSM (one in four) vs Caucasian MSM (one in 11).
- People living in Georgia (one in 51) vs North Dakota (one in 670).
Take Home Pearl: The estimated lifetime risk of being diagnosed with HIV in the U.S. appears to have decreased in recent years, but racial and geographic disparities persist.
Injection Drug-Related HIV in Rural Regions
The Particulars: In January 2015, the Indiana State Department of Health investigated 11 apparent injection drug-related HIV infections in the rural town of Austin. This city is in a county that usually has fewer than five new HIV infections per year.
Data Breakdown: For a study, researchers found that, as of February 2016, 188 people were infected with HIV in Austin in less than 15 months, 90% of whom also had hepatitis C. The prevalence of HIV in the city is estimated to be 4.6%. The drug of choice among the entirely Caucasian population during this outbreak was oxymorphone, which was injected an average of four to 15 times per day by users. Austin is like many areas in the United States; access to care, HIV risk awareness, and education levels are low and poverty, unemployment, and addiction rates are high. Only one part-time family physician practices in the city, and the nearest HIV care center is at least 45 minutes away.
Take Home Pearls: Rural regions in the U.S. appear to be at risk for HIV outbreaks that are similar to the one that has occurred in Austin, Indiana because of an apparent increase in opioid addiction. The notion that HIV is concentrated in inner cities and among minorities may no longer be true.
Life Expectancy & HIV Status
The Particulars: Prior research indicates that the use of combination antiretroviral therapy (ART) has helped dramatically improve survival rates for patients with HIV in recent years. However, little is known about how survival among HIV-infected patients compares with that of people not infected with the virus.
Data Breakdown: Researchers in California matched HIV-infected adults with HIV-uninfected adults by age, gender, medical center, and year. They assessed differences in life expectancy at age 20 during 1996-2006 and 2007-2011. Among the findings:
|HIV-infected patients||HIV-uninfected patients|
|Mortality rate (per 100,000 person years)||1,827||326|
|Life expectancy at age 20 (1996-2006)||36.0 years||62.3 years|
|Life expectancy at age 20 (2007-2011)||48.5 years||62.3 years|
Patients with HIV who exhibited the lowest life expectancy at age 20 in 2007-2011 were African Americans (45.2 years) and those with a history of injection drug use (42.6 years). In 2007-2011, HIV patients who initiated ART at 500 cells/µL or higher had a life expectancy at age 20 of 53.8 years.
Take Home Pearl: Even among people with HIV who start ART early, there appears to be an approximate 9-year gap in life expectancy between HIV-infected and HIV-uninfected patients among individuals with access to care.
Benefits Seen With Prompt HIV Treatment
The Particulars: International guidelines recommend that all patients be offered antiretroviral therapy (ART) upon receiving an HIV diagnosis. Whether this is feasible and improves outcomes when compared with delaying treatment is not well known.
Data Breakdown: For a study of patients with newly diagnosed HIV, researchers compared outcomes between those who were offered ART immediately (rapid treatment) and those who waited to start the therapy for up to six clinic visits (standard care). Among those in the rapid treatment group, 97% had initiated ART within 90 days, compared with a rate of 72% that was observed in the standard care group. Nearly 65% of patients in the rapid treatment group remained in care and achieved viral suppression, compared with a rate of 51% that was seen in the standard care group.
Take Home Pearl: Upon HIV diagnosis, patients who are immediately offered ART are more likely to start treatment, achieve viral suppression, and remain in care when compared with those who undergo a waiting period before being offered ART.
ART & Perception of Infectiousness
The Particulars: Previous studies have found that antiretroviral therapy (ART)-induced viral suppression helps reduce sexual transmission of HIV. However, ART does not produce immediate or universal viral suppression. Changes in a patient’s perception of infectiousness (POI) as a result of ART may impact sexual behaviors, which in turn may have an impact on HIV transmission and population incidence.
Data Breakdown: Patients with HIV who had never received ART provided self-reports of POI at baseline and annually for a study in which all participants were started on ART. Nearly half (49%) reported a reduction in POI from baseline to 48 weeks. The following factors were associated with a greater risk of a decline in POI:
- Higher baseline POI.
- Younger age.
- Higher education.
African-American race and a pre-ART CD4 count of more than 50 were associated with a lower risk of a decline in POI. Only 8 of the 99 participants in the study who reported being non-infectious on ART at week 48 had RNA levels greater than 50 c/mL.
Take Home Pearls: Nearly half of patients with HIV appear to report a reduction in POI 48 weeks after initiating ART. However, relatively few patients appear to perceive themselves as non-infectious.
For more information on these studies and others that were presented at CROI 2016, visit http://www.croiconference.org.