STI rates in PrEP users very high, but evidence that PrEP increases them is inconclusive

nam/aidsmap, Published: 22 February 2017
A study of PrEP users presented last week showed that PrEP users had very high rates of STI diagnosis – in the order of 20 times higher than among HIV-negative gay men in the general population. The evidence that STIs increased further while people were on PrEP was, however, a lot more ambiguous.
The problem in proving that PrEP has any causal relationship to STIs is that STIs among gay men were, in general, rising before well before PrEP, and also that PrEP usually involves regular testing for HIV and STIs. Since many STIs are asymptomatic and self-limiting, more tests will result in more diagnoses.
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