Our study highlights the association with risk for HIV among MSM and PrEP awareness prior to PrEP being widely available in Brazil and before large scale PrEP implementation in select regions of Mexico and Peru. PrEP awareness was highest in Brazil; those at higher risk for HIV were more aware of PrEP. However, the point estimate for higher risk MSM compared to lower risk MSM in Brazil was small (aPR 1.04). In Mexico and Peru, higher risk for HIV was not associated with PrEP awareness. Overall, the findings from this study are troublesome, as those who are at higher risk for HIV and most likely in need of PrEP, may not be aware. Therefore, if awareness in these groups are low, it is likely that PrEP uptake and thus, prevention of new HIV cases with PrEP will be lower. It is essential to focus prevention efforts to target these populations who may be at highest risk for HIV and where the epidemic may continue.
It is likely that the association of higher risk for HIV and PrEP awareness between these three countries reflects the duration of PrEP availability and accessibility of PrEP in each. Brazil has had PrEP for the longest time and has made it available at the national level, whereas Mexico and Peru have only recently implemented PrEP in a few sites (25, 26). These differences may explain the greater overall percentage of awareness in Brazil in comparison to Mexico and Peru. The findings from this study show that PrEP implementation in the health systems of these countries and the information of PrEP’s availability need to be further disseminated to increase levels of awareness. It is predicated that as PrEP implementation in these three countries continues, awareness of PrEP will also increase. As seen in previous studies, willingness to use PrEP is strongly associated with awareness (27-29, 35). Therefore, focus on increasing awareness of PrEP is an important first step in targeting its uptake and use.
This study contributes to important findings about variables that are associated with PrEP awareness. PrEP awareness has been previously shown to be associated with older age, higher education, and higher income among those from Brazil (28-30). These findings held true in our study. PrEP awareness was associated with older age in Brazil and Peru. In Brazil and Mexico, higher than high school education was positively associated with PrEP awareness. Furthermore, higher income was associated with increased PR of PrEP awareness, while lower income was negatively associated with PrEP awareness in the three countries. This association highlights that those of higher education or higher income may be receiving or have access to information about PrEP, but those of lower education or lower income may not. This is of concern because those of lower income may have less access to health services compared to those who are of higher income (34). Further, risk for HIV among those of lower income may be as high or higher compared to those of higher income. This population, in addition to higher risk individuals, is one in which PrEP knowledge and service dissemination may be highly beneficial. This may also be true for those with lower education. Additionally, those of lower education may have less access to sexual health education and thus less awareness of PrEP as seen in a population of black MSM in New York City, New York, United States (40). Therefore, future interventions should focus on reaching these groups (27, 40).
Other variables associated with PrEP awareness in our study population included use of GSN apps and substance use. Daily use of GSN apps to find sex partners was positively associated with PrEP awareness in Brazil. Agreeing with other literature, this finding shows that GSN applications may be used as a platform to spread awareness of PrEP and education (29, 41, 42). Exposure to PrEP information in GSN applications may occur through advertisements or in users’ profiles where they indicate PrEP use (41, 43). Further, never use of GSN applications showed a negative association with PrEP awareness in Mexico and Peru. Thus, individuals who never use GSN applications may be less exposed to PrEP information while those who use GSN applications daily are more exposed to information. Use of GSN applications may also be a proxy for social factors that would increase exposure to PrEP information (41). Substance use (marijuana use only, erectile dysfunction drugs use only, and use of both) was positively associated with PrEP awareness in all three countries. Use of these substances may reflect proxy associations with PrEP awareness due to social and behavioral factors other than just using the substances. As shown previously in Brazil, having more than 5 partners in the previous 6 months, having more friends with the same sexual orientation, and marijuana use is associated with PrEP awareness (30). Erectile dysfunction drugs use is suspected to be used in junction with sex and may increase the number of sex partners one has. Thus, it is possible that one’s exposure to others (which may include friends/partners with the same sexual orientation) who may know about or use PrEP, increases their awareness of PrEP. Similarly, marijuana may be used with others (friends with the same sexual orientation), which may increase the possibility of exposure to PrEP information.
This study was made available to individuals on social media platforms such as Facebook© and GSN apps such as Grindr© and Hornet©. Participants that came across the advertisements were not incentivized to participate in the survey. Over 40,000 participants started the survey and 19,457 were included in the analyses. Information bias, specifically social desirability bias, may be limited because the surveys were anonymous and filled out at the individuals’ will. No identifying information was collected; therefore, the effect of stigma and other social factors may be reduced. Finally, we were able to obtain large sample sizes from all three countries throughout the different regions of the countries. The distribution of higher risk individuals reflected the regions where HIV is most prevalent in these countries.
This study has some limitations that must be addressed. The final sample size for Brazil, Mexico, and Peru was 11,325, 5,921, and 2,150 for descriptive analyses respectively, but were slightly reduced in the multivariable models because of missing data. Brazil retained 95% of respondents, while Mexico retained 88%, and Peru retained 85%. Respondents had the ability to state “I don’t know, or I don’t want to answer” to questions, which was considered missing in the analysis. Differences in missing data by country may induce selection bias related to exposure and confounder information. Second, all information collected on individuals was self-reported. We did not have access to medical records or other sources of data to cross check for misclassification. Recall bias may also impact the results as respondents were asked about exposures from 3 months, 6 months, and 12 months from the time of the survey. Third, selection bias may also exist in this study due to convenient sampling. The study design aimed to limit selection bias by making the study available to participants in the three countries on multiple online forums and by allowing the survey to be disseminated to peers who may have not had access to these online sites. However, respondents needed access to a smartphone or computer and internet access thus, missing those without access. Moreover, education and income reflected distributions similar to those in Brazil, Mexico, and Peru, but higher income and higher education seemed to be overrepresented. Finally, there were some differences in how questions were posed between the countries. Specifically, income in Brazil was asked as family income, while income in Mexico and Peru was asked as individual income. Therefore, conclusions of income in Brazil are different than those for Mexico and Peru.