[Young men who have sex with men: a group at high risk for HIV infection?]

To compare variables associated with the risk of HIV among men ≤ 25 years old who have sex with men (YMSM) and those >25 years old, and to determine the variables associated with unprotected anal intercourse (UAI) in YMSM with casual sexual partners.

For 1 month, 485 participants ≤ 25 years old and 1,470 aged >25 years old completed a pen-and-paper survey carried out in gay venues (GV) or via the Internet in Madrid, Barcelona, Bilbao and San Sebastián (Spain). The survey investigated sexual behaviors in the past 3 months according to whether the men met sexual partners in GV (SPGV) or on the Internet (SPI).

No significant differences were found between YMSM and those >25 years old with respect to UAI with SPGV (23% vs. 30%, p>0.05) and SPI (29% vs. 30%, p>0.05), condom use in the last anal intercourse and having had a sexually-transmitted infection (STI) in the last year (19% vs. 23%, p>0.05). However, respondents>25 years old had a higher average number of SPGV (9.2 vs. 7, p<0.05) and SPI (8.9 vs. 6.4, p<0.05), were more likely to have used drugs while having UAI (68% vs. 55%, p<0.05, with SPI, and 73% vs. 55%, p<0.05, with SPGV) and had a higher prevalence of HIV (11% vs. 4%, p<0.05). When exploring other variables, we found that YMSM more frequently had receptive UAI with SPI (73% vs. 57%, p<0.05), had less time to be in a stable relationship, and their sexual partner more frequently convinced them to have UAI (8% vs. 0%, p<0.05). In multivariate analysis, UAI in YMSM with casual sexual partners was not associated with any of the variables.

YMSM do not constitute a group at increased risk of HIV/STI infection compared with respondents >25 years old. However, there are some variables could contribute to vulnerability in this group.