[High-risk sexual behaviour by partner type among men who have sex with men]

To identify factors associated with high risk sexual practices among men who have sex with men (MSM) in Spain.

An online survey was conducted in 2010, which included, among others, questions on HIV/STI sexual behaviours and prevention needs. Unprotected anal intercourse (UAI) with a partner of unknown or discordant HIV status in the past year was defined as a high risk sexual behaviour.

Of the 13,111 participants, 49.4% had had sex with steady partners (SP) and 73.4% with non-steady partners (NSP) in the last 12months; and the prevalence of high risk UAI was 25.4% and 29.4%, respectively. Factors associated with high risk UAI with SP were: living in a city of less than 500,000 inhabitants (OR=1.42 <100,000 inhabitants), being out to no-one or only a few people (OR=1.42), and being HIV-positive with undetectable viral load among those with a high level of HIV/STI knowledge (OR=3.18). Factors associated with high risk UAI with NSP were mainly: having a higher number of sexual partners (OR=4.31 >50 partners), having used drugs for sex (OR=1.33), and at parties (OR=1.19), having a medium (OR=1.82) or low (OR=1.33) level of HIV/STI knowledge, and being HIV-positive (OR=1.56).

Among MSM, the prevalence of high risk sexual practices is high with both SP and NSP. Factors associated with high risk UAI vary by type of sexual partner (e.g., having HIV with an undetectable viral load). These must be taken into account when planning strategies for primary and secondary prevention.