Condom use rates have apparently followed a steady decline among men who have sex with men (MSM) over the past decade, irrespective of serosorting or use of HIV treatment, aidsmap reports. Publishing their findings in the journal AIDS, researchers analyzed National HIV Behavioral Surveillance (NHBS) data from surveys conducted in 2005, 2008, 2011 and 2014 in 21 U.S. cities among 1,110 to 1,600 MSM per survey.

The men were recruited for the study at places where MSM tend to congregate, including bars and clubs, social organizations, gay businesses, bathhouses and parks. They were asked whether they used a condom during their most recent anal sex experience, as opposed to how often they use condoms. Posing the question this way increases the accuracy of men’s recall; it also allows researchers to extrapolate these answers and ultimately get a better sense of how often a certain sexual act occurs in an overall population.

An initial report about the NHBS data, released in January, found that condom use has fallen among MSM, but that its use varies by context.

Among HIV-negative men, the rate of reported condomless intercourse rose from 28.7 percent in 2005 to 32.8 percent in 2008, 34.7 percent in 2011 and 40.5 percent in 2014. On the serosorting front (serosorting is the practice of favoring sex, or condomless sex, with partners of the same HIV status), 21.2 percent of HIV-negative men in 2005 reported having condomless sex with a man they believed to be HIV negative, a figure that rose to 27.4 percent in 2015. During this period, the proportion of HIV-negative men reporting condomless sex with an HIV-positive or unknown-status partner rose from 7.6 percent to 13.1 percent.

The greatest increases in reported condomless intercourse were among men 18 to 24 years old.

A total of 0.5 percent of the HIV-negative men reported using Truvada (tenofovir/emtricitabine) as pre-exposure prophylaxis (PrEP) in 2011. By 2014, this figure had risen to 3.5 percent. The researchers concluded that PrEP use was too low during these years to contribute to increases in condomless sex rates. Excluding men on PrEP from their analyses did not change the findings about condom use trends.

Among HIV-positive men, the rate of those reporting condomless sex during their most recent act of intercourse was 34.2 percent in 2005, a figure that rose to 37.3 percent in 2008, 39.8 percent in 2011 and 44.5 percent in 2014. The rate of positive men reporting condomless sex with men of the same HIV status increased from 19 percent in 2005 to 25.4 percent in 2014. During this period, the rate of positive men who reported condomless sex with men who were HIV negative or of unknown HIV status increased from 15 percent to 19 percent.

The rate of HIV-positive men reporting receptive condomless sex with HIV-negative or unknown-status men rose between 2005 and 2014, while the rate of positive men reporting insertive condomless sex with this demographic did not. This is likely an indication of men practicing what is known as seropositioning, in which men favor certain sexual positions based on a sexual partner’s HIV status (there is less chance of HIV transmission if an HIV-negative man is the insertive partner, or the top, with an HIV-positive man, compared with having the roles reversed).

Condomless sex rates rose over time among HIV-positive men on antiretrovirals (ARVs) as well as those not on treatment.

The researchers concluded that “condom use has decreased among MSM and that the trends are not explained by serosorting, seropositioning, PrEP use or HIV treatment.”

Because the participants were recruited from cities with high rates of HIV, the study’s findings are not necessarily generalizable nationwide.

The fact that the data relies on self-reporting is a major limitation of the study. The authors noted that it is possible that the inclusion of sexual behavior questions starting in 2011 might have limited the participant pool going forward to people who are more comfortable disclosing their sexual behaviors (and who thus feel more free to state that they have engaged in condomless sex, for example). Additionally, diminishing stigma surrounding HIV infection or homosexuality in recent years might also have compelled participants in recent surveys to feel more comfortable disclosing sexual behaviors compared with those in older surveys. These factors might have artificially inflated the apparent increases in sexual risk taking among the participants.

To read the aidsmap article, click here.

To read the study abstract, click here.