[Internet and sexual risk in men who have sex with men]

1) To compare sociodemographic characteristics, Internet use to seek sexual partners, and sexual behavior in two samples of men who have sex with men: one sample that was surveyed on-line and another that was interviewed in gay venues. 2) To determine the variables associated with unprotected anal intercourse with sexual partners met on-line.

For 1 month, 804 men who have sex with men completed a pen-and-paper survey in gay venues and 1,240 completed a web survey in Madrid, Barcelona and Bilbao/San Sebastián (Spain).

The sociodemographic characteristics differed in the two samples. Compared with men who have sex with men surveyed off-line, a higher proportion of those surveyed on-line used the Internet to meet sexual partners (81% vs. 65%, p<0.05), had unprotected anal intercourse with sexual partners met on-line (31% vs. 27%, p>0.05), had intentionally practised unprotected anal intercourse (81% vs. 65%, p<0.05), did not know their HIV status (35% vs. 28%, p<0.05), used drugs when they practised unprotected anal intercourse (68% vs. 55%, p<0.05) and had had a sexually transmitted infection in the previous year (24% vs. 20%, p<0.05). In the multivariate analysis, unprotected anal intercourse with sexual partners met on-line was associated with having more than 20 sexual partners (odds ratio [OR]: 1.528; 95% confidence interval [95%CI]: 1.024-2.282; p=0.038), using drugs before/during sexual relations (OR: 1.962; 95% CI: 1.478-2.604; p=0.000), having had a sexually transmitted infection in the previous year (OR: 2.042; 95% CI: 1.535-2.716; p=0.000) and being HIV-positive (OR: 2.124; 95% CI: 1.355-3.330; p=0.001), amongst other factors.

Although the prevalence of unprotected anal intercourse was similar in the two samples, certain variables could explain why the men who have sex with men surveyed on-line had a greater risk of sexually transmitted infections than those surveyed off-line.