Screening for HIV Infection in Asymptomatic, Nonpregnant Adolescents and Adults: Updated Evidence Report and Systematic Review for the US Preventive Services Task Force

Abstract

Importance: Untreated HIV infection can result in significant morbidity, mortality, and HIV transmission. A 2012 review for the US Preventive Services Task Force (USPSTF) found antiretroviral therapy (ART) associated with improved clinical outcomes and decreased transmission risk in persons with CD4 cell counts less than 500/mm3.

Objective: To update the 2012 review on HIV screening to inform the USPSTF.

Data sources: Ovid MEDLINE, the Cochrane Central Register of Controlled Trials, and the Cochrane Database of Systematic Reviews from 2012 to June 2018, with surveillance through January 2019.

Study selection: Nonpregnant individuals 12 years and older; randomized clinical trials (RCTs) and controlled observational studies of screening vs no screening, alternative screening strategies, earlier vs later initiation of ART, and long-term harms of ART.

Data extraction and synthesis: One investigator abstracted data; a second checked accuracy. Two investigators independently rated study quality.

Main outcomes and measures: Mortality, AIDS events, quality of life, function, and HIV transmission; harms of screening and long-term (≥2 years) harms of ART; screening yield.

Results: Eighteen new studies (5 RCTs, 11 cohort studies, and 2 systematic reviews; N = 266 563) were included, and 11 studies (2 RCTs and 9 cohort studies; N = 218 542) were carried forward from the prior USPSTF report. No study directly evaluated effects of HIV screening vs no screening on clinical outcomes or harms, or the yield of alternative screening strategies. Two newly identified RCTs conducted completely or partially in low-resource settings found ART initiation at CD4 cell counts greater than 500/mm3 associated with lower risk of a composite outcome of mortality, AIDS-defining events, or serious non-AIDS events (relative risk [RR], 0.44 [95% CI, 0.31-0.63] and RR, 0.57 [95% CI, 0.35-0.95]); results were consistent with those from a large observational study. Early ART was not associated with increased risk of cardiovascular events. Early ART initiation was associated with sustained reduction in risk of HIV transmission at 5.5 years (RR, 0.07 [95% CI, 0.02-0.22] for linked transmission). New evidence regarding the association between abacavir use and risk of cardiovascular events was inconsistent. Certain antiretroviral regimens were associated with increased risk of long-term neuropsychiatric, renal, hepatic, and bone adverse events.

Conclusions and relevance: In nonpregnant adolescents and adults there was no direct evidence on the clinical benefits and harms of screening for HIV infections vs no screening, or the yield of repeat or alternative screening strategies. New evidence extends effectiveness of ART to asymptomatic individuals with CD4 cell counts greater than 500/mm3 and shows sustained reduction in risk of HIV transmission at longer-term follow-up, although certain ART regimens may be associated with increased risk of long-term harms.