At their first screening visit, people who opt to take pre-exposure prophylaxis (PrEP) to prevent HIV are diagnosed with sexually transmitted infections (STIs) at a high rate and maintain a high diagnosis rate thereafter, Healio reports.

This finding from a systematic review and meta-analysis of dozens of PrEP studies is separate from the question of whether starting PrEP leads to a change in users’ STI acquisition rates.

The high STI rate among PrEP users is actually a sign that they stand to benefit from this form of HIV prevention, considering that the sexual behaviors associated with gonorrhea, chlamydia and syphilis acquisition—specifically, condomless intercourse—overlap with those associated with HIV risk. Additionally, individuals who are already contracting such infections at a high rate can further benefit from the quarterly STI screenings recommended for those receiving PrEP and receive antibiotics for any such infection in the event of a positive test result.

Jason J. Ong, PhD, MBBS, an associate professor in the department of clinical research at the London School of Hygiene & Tropical Medicine, and colleagues conducted a systematic review and meta-analysis of 88 studies of PrEP use, which provided data from 26 countries. They published their findings in JAMA Network Open.

Seventy percent of the studies were conducted in high-income nations, and 66% included only men who have sex with men (MSM).

When the study participants were initially screened for PrEP, 23.9% were diagnosed with chlamydia, gonorrhea or syphilis. When broken down by infection site, the highest STI diagnosis rate was in the anal and rectal area compared with the genitals or the mouth and throat.

STI diagnosis in the anal and rectal area has a particularly strong association with HIV risk, since it is linked to condomless receptive anal intercourse—the riskiest sexual act when it comes to HIV.

During the studies’ follow-up periods, the cumulative diagnosis rate of chlamydia, gonorrhea and syphilis was 72.2 diagnoses per 100 cumulative years of follow-up. This means that in one year 1,000 people would be diagnosed with 772 STIs.

“Given the high STI burden among individuals initiating PrEP and among persistent PrEP users, there are opportunities to leverage the global interest in PrEP policy and the development of programs to actively promote the integration of STI services, which includes appropriate asymptomatic testing, treatment and targeted vaccination,” the study authors concluded.

To read the Healio article, click here.

To read the study, click here.