A longitudinal study using multiple cohorts of young men who have sex with men in Chicago aimed to investigate changes in condom use over time, from late adolescence to adulthood (aged 17-26), as well as historical patterns of change for cohorts of men recruited in different years. This research was carried out by Gregory Swann and colleagues at Northwestern University and is published in the May issue of The Archives of Sexual Behavior.
Researchers found that while men had more anal sex as they got older, there was a decrease in the proportion of that sex that was condomless. In terms of historical changes, of the three cohorts followed (recruited in 2007, 2010 and 2015), the 2015 cohort reported less condomless sex at age 17, but a higher growth in the proportion of sex that was condomless as they got older. This study is the first of its kind to indicate that cohorts recruited in more recent years may have different risk trajectories over time when compared to cohorts recruited previously.
Young men who have sex with men (MSM) have the highest HIV incidence in the US. Between 2001 and 2011, youth between the ages of 13 and 24 represented the fastest growing age group for new infections. In 2015, rates of new diagnoses stabilised for this age group but continued to increase among MSM aged 25-34, with a 23% increase from 2010 to 2015.
“Given these high rates and trends, understanding how HIV risk changes from adolescence to young adulthood is especially important,” the authors say. “The goal of the present study was to observe how engagement in condomless anal sex changes over time from late adolescence to adulthood in young MSM. We also set out to assess whether cohorts of young MSM recruited in 2007, 2010, and 2015 differed in patterns of change in condomless anal sex from late adolescence to adulthood.”
In terms of historical changes, social factors, such as greater recognition of same-sex relationships and marriage equality, and biomedical developments, such as pre-exposure prophylaxis (PrEP) and treatment as prevention (TasP), may have had an impact. However, PrEP is only FDA-approved for those over 18 years of age and uptake has been low among young MSM, especially those of colour. Thus, condom use is still an important HIV prevention tool for this at-risk group.
Turning to changes as young men get older, previous longitudinal research on condom use has had varied findings. One study found that MSM who were younger at baseline were more likely to have higher increases of condomless sex over time; another found no significant changes over time in terms of condomless sex acts; and one reported that individuals were inconsistent over time in their sexual risk behaviour. However, these studies tended to follow men for less than two years and thus do not offer insight into change over longer periods of time.