Suboptimal laboratory testing at PrEP initiation in the United States, 2022-2023

Abstract

Introduction: To ensure the safe use of preexposure prophylaxis (PrEP) for HIV prevention, the Centers for Disease Control and Prevention (CDC) recommends laboratory testing with specific tests for all individuals before PrEP initiation.

Methods: We analyzed the Merative™ MarketScan® commercial insurance database to assess the use of laboratory testing for HIV antigen/antibody (Ag/Ab), HIV RNA tests, sexually transmitted infection, Hepatitis B virus infection, and other CDC-recommended testing for persons who initiated PrEP during 2022-2023. We estimated testing rates for each laboratory assay based on its specific recommendation at the time of PrEP initiation, which was defined as the interval extending from 14 days prior to through 14 days following the recorded initiation date.

Results: Among 38,855 persons who initiated PrEP during 2022-2023, only 35.3% had a documented laboratory-based HIV Ag/Ab test during the ± 14-day period. Among 757 injectable PrEP users, only 35.4% were tested for HIV RNA during the ± 14-day period. Testing rates of other recommended laboratory tests were also low. Persons who were prescribed oral PrEP, who reside in the South and in non-metropolitan areas had lower testing rates for all laboratory tests.

Conclusions: CDC-recommended laboratory testing was suboptimal at PrEP initiation. Some PrEP users might have been tested for HIV by using only a point-of-care (POC) test to facilitate rapid PrEP initiation despite a recommendation to confirm with a laboratory-based test. Implementation of clinical decision supports with laboratory order sets tailored to each type of PrEP medication could increase adherence to CDC-recommended laboratory testing at PrEP initiation.

Keywords: CDC guidelines; HIV; PrEP; STI; laboratory testing.