Date of Completion


Embargo Period



Stephanie Milan, Blair T. Johnson

Field of Study


Open Access

Campus Access


Objective: To investigate longitudinally the association between perceived risk of HIV transmission given undetectable viral load and unprotected sex between partners with different HIV status. Two alternative hypotheses are tested: lower perceived risk leads to more unprotected sex later in time, or lower perceived risk is a result of more previous engagement in unprotected sex. Methods: The study population included 186 people living with HIV/AIDS (PLWHA) who were on HIV medication in Atlanta, Georgia, USA. The three waves of data were collected using audio computer-assisted self-interview between Oct 22, 2012 and January 16, 2014. Results: Cross-sectional correlation between perceived risk and unprotected sex was statistically significant in first two waves of data, but not the third wave. Longitudinal analysis reveals that perceived risk of transmission failed to consistently predict more unprotected sex, but unprotected sex significantly predicted a lower perceived risk later in time. Conclusion: an increase in unprotected sex is often considered as a result of people becoming more optimistic about a reduced risk for HIV transmission, but findings from this study lent more support to a feedback loop from more unprotected sex to reduced perceived risk. Future studies are needed to further test the stability of the relationship and to explore the mechanism behind this relationship.

Major Advisor

Seth Kalichman