EXECUTIVE SUMMARY

The Centers for Disease Control and Prevention currently recommends that all citizens be tested for HIV infection at least once between the ages of 13 and 64 years. Results of a recent study indicate that age 25 would be better than younger ages for a single HIV screening test among those young adults without symptoms.

  • The findings indicate that compared with current U.S. screening practices, a screen at age 25 would lead to the most favorable care continuum outcomes in terms of proportion diagnosed, linkage to care, retention in care, and virological suppression.
  • Researchers found that compared with the next most effective screen, a screen at age 25 provided the most clinical benefit, and was cost-effective.

The Centers for Disease Control and Prevention (CDC) currently recommends that all citizens be tested for HIV infection at least once between the ages of 13 and 64 years. Results of a recent study indicate that age 25 would be better than younger ages for a single HIV screening test among those young adults without symptoms.1

Researchers at Massachusetts General Hospital collaborated with the CDC and the Massachusetts Department of Public Health to develop the new analysis. They used CDC data on new HIV diagnoses in 2013 and the stage of disease at the time of diagnosis to compare the probable results of implementing a one-time HIV screening test at various ages between 13 and 30. Outcomes included virologic suppression, life expectancy, lifetime costs, retention in care, and incremental cost-effectiveness ratios in dollars/year-of-life saved from the healthcare system perspective. In sensitivity analyses, the study varied HIV incidence, screening and linkage rates, and costs.

The analysis indicates that compared with current U.S. screening practices, a screen at age 25 would lead to the most favorable care continuum outcomes in terms of proportion diagnosed (77% vs. 51%), linkage to care (71% vs. 51%), retention in care (68% vs. 44%), and virological suppression (49% vs. 32%). Researchers found that compared with the next most effective screen, a screen at age 25 provided the most clinical benefit, and was cost-effective.1

Researchers note that the analysis results do not apply to youth at high risk, such as gay and bisexual males, who should be tested more frequently. Other populations at high risk for HIV infection include people who inject drugs and their sex partners, people who exchange sex for money or drugs, and sex partners of people who are infected with HIV.

“For at-risk groups, HIV screening should occur much more frequently than once in a lifetime, since a single screen will only capture a very small proportion of the population with HIV,” said Andrea Ciaranello, MD, MPH, senior author of the study in a press statement. “However, for young people who become infected by age 25, the gains in life expectancy and improvements in health outcomes, including viral suppression, from that one-time screening test would be substantial.”

What Are the Next Steps?

The current analysis indicates that from 2009 to 2013, HIV diagnoses in those ages 13-29 were highest in ages 22-25. Since there often is a delay between when someone becomes infected with HIV and when the person is diagnosed, scientists cannot be certain at what age most infections are occurring, notes Richard Dunville, MPH, research officer in the CDC’s Division of Adolescent and School Health and study coauthor. However, the study leads scientists to doubt that screening adolescents who are 18 years of age and younger without risk factors would be a “good use” of limited resources, he notes.

The benefits of a one-time HIV screening test appeared lower if youth found to be living with HIV did not remain in care and on antiretroviral medications, the researchers note.

“Interventions to support linkage to care and retention in care are critical,” says Ciaranello, assistant professor of medicine at Harvard Medical School. “Our study underscores the value of ongoing research supported by the National Institutes of Health to examine the most effective ways to improve health outcomes for youth with HIV.”

About half of all young people ages 13-24 who have HIV do not know they are infected, but less than 15% of adults with HIV are unaware, notes study lead author Anne Neilan, MD, MPH, of the Massachusetts General Hospital’s Division of Infectious Diseases and the Medical Practice Evaluation Center.

“HIV screening is an important component of addressing this disparity,” said Neilan in a press statement. “Our results indicate that focusing screening on teens 18 or younger without risk factors would be a less efficient use of a one-time screen than screening at a later age.”

In 2015, youth ages 13 to 24 represented 22% of all new HIV diagnoses in the United States. Most (81%) of the new diagnoses were found in gay and bisexual males. Young black/African American and Hispanic/Latino gay and bisexual males were especially affected.2

Researchers recently have obtained funding to develop mobile apps that aim to increase HIV testing, and use of and adherence to pre-exposure prophylaxis (PrEP) to prevent HIV infection among young people. For those who test positive for HIV, scientists plan to create electronic health interventions to link them with care and improve adherence to antiretroviral therapy. (See more on this subject; read the December 2016 STI Quarterly supplement article, “Researchers Develop Mobile Technology to Prevent and Treat HIV in Young Adults,” at http://bit.ly/2qPaOrp.

REFERENCES

  1. Neilan AM, Dunville R, Ocfemia MCB, et al. The optimal age for screening adolescents and young adults without identified risk factors for HIV. J Adolesc Health 2018;62:22-28.
  2. Centers for Disease Control and Prevention. Diagnoses of HIV infection in the United States and dependent areas, 2015. HIV Surveillance Report 2016:27.