Temporal Fluctuations in Behavior, Perceived HIV Risk, and Willingness to Use Pre-Exposure Prophylaxis (PrEP)

  • Kristen Underhill
  • Kate M. Guthrie
  • Christopher Colleran
  • Sarah K. Calabrese
  • Don Operario
  • Kenneth H. Mayer
Original Paper


Individual perceptions of HIV risk influence willingness to use pre-exposure prophylaxis (PrEP) for HIV prevention. Among men who have sex with men (MSM) and male sex workers (MSWs), temporal or episodic changes in risk behavior may influence perceived risk and PrEP acceptability over time. We investigated fluctuations in perceived HIV risk and PrEP acceptability, comparing MSWs against MSM who do not engage in sex work. We conducted 8 focus groups (n = 38) and 56 individual interviews among MSM and MSWs in Providence, RI. Perceived HIV risk shaped willingness to use PrEP among both MSWs and MSM who did not engage in sex work, and risk perceptions changed over time depending on behavior. For MSWs, perceived risk cycled according to patterns of substance use and sex work activity. These cycles yielded an “access-interest paradox”: an inverse relationship between willingness to use and ability to access PrEP. MSM who did not engage in sex work also reported temporal shifts in risk behavior, perceived risk, and willingness to use PrEP, but changes were unrelated to access. MSM attributed fluctuations to seasonal changes, vacations, partnerships, behavioral “phases,” and episodic alcohol or drug use. Efforts to implement PrEP among MSM and street-based MSWs should address temporal changes in willingness to use PrEP, which are linked to perceived risk. Among MSWs, confronting the access-interest paradox may require intensive outreach during high-risk times and efforts to address low perceived risk during times of reduced sex work.


Pre-exposure prophylaxis Men who have sex with men Male sex work HIV prevention Sexual orientation 



This study was supported by the National Institute of Mental Health, 5K01MH093273 (PI: Underhill). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the article. S.K. Calabrese and K.H. Mayer have received compensation for their efforts in developing and/or delivering medical education related to PrEP. K.H. Mayer has conducted research with unrestricted project support from Gilead Sciences, Merck, and ViiV Healthcare. S.K. Calabrese was supported by 5K01MH103080 from the National Institute of Mental Health (NIMH). K.M. Guthrie was supported by 5K24HD062645 from the National Institute of Child Health and Human Development. We are grateful to the study participants, Project Weber, Miriam Community Access, the Yale Center for Interdisciplinary Research on AIDS, the Lifespan/Tufts/Brown Center for AIDS Research, Melissa Guillen, Genevieve Ilg, Bobby Ducharme, and Dr. Caroline Kuo for help during the implementation of this study. Kristen Underhill and Sarah Calabrese were both based at Yale University when this work was conducted.


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Copyright information

© Springer Science+Business Media, LLC 2018

Authors and Affiliations

  • Kristen Underhill
    • 1
    • 2
  • Kate M. Guthrie
    • 3
    • 7
  • Christopher Colleran
    • 3
  • Sarah K. Calabrese
    • 4
  • Don Operario
    • 5
  • Kenneth H. Mayer
    • 6
  1. 1.Columbia Law SchoolColumbia UniversityNew YorkUSA
  2. 2.Heilbrunn Department of Population and Family Health, Mailman School of Public HealthColumbia UniversityNew YorkUSA
  3. 3.Centers for Behavioral and Preventive MedicineThe Miriam HospitalProvidenceUSA
  4. 4.Department of PsychologyGeorge Washington UniversityWashingtonUSA
  5. 5.School of Public HealthBrown UniversityProvidenceUSA
  6. 6.The Fenway InstituteFenway HealthBostonUSA
  7. 7.Department of Psychiatry and Human Behavior, Warren Alpert Medical SchoolBrown UniversityProvidenceUSA

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