PREreview of PrEP Surfing: HIV Pre-Exposure Prophylaxis (PrEP ) Use of Sexual Partners as HIV Prevention Strategy Among Men Who Have Sex with Men, an Analysis of the Amsterdam Cohort Studies

PrEP Surfing: HIV Pre-Exposure Prophylaxis (PrEP ) Use of Sexual Partners as HIV Prevention Strategy Among Men Who Have Sex with Men, an Analysis of the Amsterdam Cohort Studies  http://dx.doi.org/10.2139/ssrn.5220658  

Summary and Overall Impression

This paper explores "PrEP surfing" while relying on a partner's PrEP use rather than taking PrEP oneself, analysing 2,187 six-monthly visits from 636 MSM participants in the Amsterdam Cohort Studies (ACS). The paper aims to estimate how common this behavior is, identify its behavioral and demographic correlates, and examine participants' intentions to surf PrEP in the future. This is a timely and original study. However, the manuscript can be significantly improved by clarifying definitions, expanding the interpretation of findings, and connecting behavior to prevention practice.

Abstract

Major Issue: The abstract lacks clarity on what "PrEP surfing" is and why it matters.

Suggestions:

• Use of a clear, plain-language definition. Example: PrEP surfing refers to engaging in condomless sex while relying on the HIV protection of a partner who is taking PrEP, without taking PrEP oneself.

• Summarize the main findings with numbers and meaning. Example: High intention to surf was reported in 27% of visits, with younger age and casual sex being key predictors.

Introduction

Major Issue: The rationale for studying PrEP surfing is introduced without connecting it to related concepts or explaining its implications.

Suggestions:

• Situate PrEP surfing within existing prevention frameworks. Example: Like serosorting or relying on a partner's undetectable viral load, PrEP surfing reflects a shift toward relational HIV prevention strategies that depend on partners' health behaviors.

• Clarify the gap this study fills. Example: No previous study has quantified the prevalence of PrEP surfing or examined the demographic and behavioural correlates of this strategy.

• State-specificity research aims to address these questions. Example: How common is PrEP surfing among MSM? What factors are associated with it? Who intends to rely on a partner's PrEP use in the future?

Methods

Major Issue: Key definitions and modelling details are under-explained.

Suggestions:

·       Specify how PrEP surfing was measured (e.g., self-report of CAS + reliance on partner's PrEP use + respondent not on PrEP).

·       Explain the exclusion of participants using only daily PrEP.

·       Clarify how intention was scored and thresholds used for "high" intention (Likert scale 6–7).

·       Describe how repeated observations per participant were handled in regression models.

·       Report handling of missing or incomplete data.

Results

Major Issue: The presentation is clear, but interpretation is lacking after numeric results.

Suggestions:

• Add interpretation after key results. Example: 25% of visits reported PrEP surfing. This indicates that partner-based protection may be shaping sexual decision-making among MSM in Amsterdam.

• Clarify the relationship between intention and behavior (if possible). Example: Of the 588 visits with high intention to surf, X% later reported actual PrEP surfing in the next visit. This shows a moderate alignment between intention and behavior.

Discussion

Major Issue: The discussion is underdeveloped. It lacks insight into behavioral drivers, clinical significance, and programmatic implications.

Suggestions:

• Interpret why people may choose to surf. Example: Younger men may perceive PrEP surfing as a lower-barrier prevention strategy due to reduced cost, stigma, or daily pill burden.

• Connect to counselling practice. Example: Clinicians should ask about reliance on partner PrEP use during risk assessments, not only personal use.

• Discuss public health messaging. Example: Health promotion campaigns should clarify that PrEP protects only the user and that partner use does not guarantee protection without verification.

• Acknowledge ethical considerations. Example: Relying on a partner's PrEP use without mutual discussion may undermine informed consent and shared responsibility.

Conclusion

Minor Issue: The conclusion does not clearly state what should happen next.

Suggestions: Add clear calls to action such as:

• Incorporate PrEP surfing questions into sexual health screening tools.

• Develop educational materials addressing the risks of relying on partner adherence.

• Study HIV transmission outcomes among PrEP surfers vs. non-users and self-users.

Othe Minor Issue: The use of abbreviations and repeated language can hinder readability.

Suggestions: Define terms on first use. Example: "CAS (condomless anal sex)" only use the acronym after it's defined.

Final Comments: This paper offers important data on a new behavioural trend in HIV prevention. The topic is relevant, the data are reliable, and the analysis is well-executed. However, to improve its impact, authors need to clarify methods and definitions, add interpretation to results, expand the discussion to cover behavioural drivers, ethical concerns, and practical implications, and conclude with actionable recommendations for researchers and practitioners. With these revisions, this paper can meaningfully inform HIV prevention strategies that account for partner-dependent behaviors.

Competing interests

The author declares that they have no competing interests.