Willingness to use pre-exposure prophylaxis: risk perception among HIV uninfected individuals in serodiscordant relationships with clients attending the Infectious Diseases Institute in Kampala

Abstract

Background: Scaling up efficacious evidence based HIV prevention strategies is imperative to realizing the UNAIDS commitment to ensure access to combination prevention methods to at least 90% of people by 2020. Pre-exposure Prophylaxis (PrEP) is one of the HIV prevention methods whose acceptability could be hampered by self-perceived risk for HIV acquisition. However, discordance between risk perception and actual risk of HIV acquisition is likely to occur. This study assessed willingness to use PrEP and the association thereof with risk perception. Methods: This was a cross-sectional study among HIV uninfected individuals in discordant relationships with clients attending a large urban HIV clinic. Proportions of HIV uninfected partners willing to adopt pre-exposure prophylaxis (PrEP) were obtained. Predictors of willingness to use PrEP; risk perception inclusive, were evaluated using bivariate and multivariate generalized linear models. Congruence between perceived risk and objectively scored risk of HIV acquisition was evaluated using descriptive statistics and validity measures. Results: The vast majority (87%) of 177 HIV uninfected partners in serodiscordant relationships with individuals receiving antiretroviral therapy at an urban clinic in Kampala were willing to use non-bridging PrEP. The partners were mostly female (64%;114/177) with mean age of 41 years (IQR 35 to 50). A greater proportion (95%;40/42) of partners who perceived themselves as being at high risk of HIV acquisition were willing to use PrEP compared to 84%(114/135) of partners who perceived themselves as low risk (PR=1.12 ;95%CI 1.02 to 1.25). However, risk perception was not associated with willingness to use PrEP in multivariate analysis. Concern about taking a daily pill was the strongest predictor of willingness to use PrEP (aPR=0.71; 95%CI 0.52 to 0.98). Perceived risk and objectively scored risk of HIV acquisition were congruent only 73% (130/177) of the time. Nearly three quarters (72.7%) of partners who were objectively scored as high risk perceived themselves as being at low risk of HIV acquisition and all were men. The proportion of participants at high risk of HIV acquisition who perceived their risk as low was greater among those who had partners with detectable viral load compared to those whose partners had undetectable viral load (PR=0.51; 95%CI 0.29 to 0.90).

Conclusion: PrEP is a well-accepted method of HIV prevention among serodiscordant couples even when the HIV infected partner has been on antiretroviral therapy long term. Risk perception is necessary to motivate PrEP use but is not sufficient. The most important barrier of willingness to use PrEP was concern about taking a daily pill. Incongruence between perceived and objectively measured risk of HIV acquisition does occur especially among individuals whose partners have detectable viral load. PrEP counselling for serodiscordant couples should focus on explaining the consequence of detectable viral load on risk of HIV transmission and rationale of adherence to daily PrEP.