Development and validation of the San Diego Early Test Score to predict acute and early HIV infection risk in men who have sex with men

Evaluating the Screening and Enrollment of People at Risk of HIV in Mexico's Preexposure Prophylaxis Demonstration Project, 2018-2020

OBJECTIVES

Screening tools in which participants self-report sexual behaviors can identify people at risk of HIV acquisition for enrollment in preexposure prophylaxis (PrEP). We compared enrollment outcomes (ie, receiving PrEP vs being excluded by a counselor or declining PrEP) in Mexico's PrEP demonstration project and evaluated the validity of a 4-criteria PrEP eligibility tool in which participants self-reported risk behavior-having condomless anal sex, transactional sex, a partner living with HIV, or a sexually transmitted infection-as compared with PrEP eligibility assessed by a counselor.

METHODS

We recruited men who have sex with men and transwomen who were offered PrEP services in Mexico. We characterized participants according to enrollment outcome and identified underlying factors through logistic regression analyses. We calculated the sensitivity and specificity of the self-reported risk criteria, using the counselor's risk assessment as the point of reference.

RESULTS

Of 2460 participants, 2323 (94%) had risk criteria of HIV acquisition according to the 4-criteria tool; 1701 (73%) received PrEP, 247 (11%) were excluded by a counselor, and 351 (15%) declined PrEP despite being considered eligible by the counselor. Participants who were excluded or who declined PrEP were less likely to report HIV risk behaviors than those who received PrEP, and participants who declined PrEP were more likely to be transwomen (vs men who have sex with men) and aged ≤25 years (vs >25 y). The 4-criteria risk tool had high sensitivity (98.6%) and low specificity (29.8%).

CONCLUSION

The screening tool identified most participants at risk of HIV acquisition, but counselors' assessment helped refine the decision for enrollment in PrEP by excluding those with low risk. Public health strategies are needed to enhance enrollment in PrEP among some groups.

A Cross-Sectional Study of Spanish Grindr Users: Sociodemographic Characteristics, Sexual Health Trends, and Attitudes toward HIV Testing

Men who have sex with men are at an increased risk of acquiring sexually transmitted infections, and although behavioral and contextual interventions have improved, infections continue to spread. Therefore, a new focus on recent trends in sexual health in this population is needed. The aim of this study was to describe the relationship between sociodemographic and behavioral characteristics according to Grindr usage patterns, the prevalence of sexually transmitted infections (STIs), and attitudes toward HIV testing. In January 2020, a cross-sectional study was conducted using a sample of 881 men who have sex with men (MSM) who completed an online questionnaire. We evaluated their Grindr use patterns (moderate or intensive) and explored the associations of these with sociodemographic behavioral characteristics, STIs, and attitudes toward HIV testing. Of 881 participants in total, 587 (66.6%) were intensive Grindr users. Compared to moderate users, these participants reported significantly higher numbers of casual sexual partners (76.2% vs. 23.8%; p < 0.001), were more likely to participate in Chemsex (77.3% vs. 22.7%: p = 0.031), and had a higher self-reported number of STIs (69.9% vs. 30.1; p = 0.046). They also demonstrated better attitudes toward HIV testing (69.7% vs. 30.3%; p = 0.045) and perceived themselves to be at moderate risk of HIV (71.2% vs. 28.8%: p = 0.048). Moreover, intensive Grindr users were 1.36 times more likely than moderate users to test positive for STIs (95%CI = 1.15-1.91; p = 0.048). With some limitations, age, sexual partners, intensive Grindr users, and PrEP uses were associated with the risk of STIs in the sample of Spanish Grindr users studied. As Grindr users are vulnerable to sociodemographic and behavioral factors that determine STIs and HIV infection, mainly among intensive users, it is necessary to highlight the importance of new trends such as online dating apps, PrEP use, substance use in sex, and Chemsex, and these need to be incorporated into online public health strategies.

Evaluating the performance of a risk assessment score tool to predict HIV acquisition among pregnant and postpartum women in Kenya

BACKGROUND

Clinical risk score tools require validation in diverse settings and populations before they are widely implemented. We aimed to externally validate an HIV risk assessment tool for predicting HIV acquisition among pregnant and postpartum women. In the context of prevention of mother-to-child transmission programs, risk score tools could be used to prioritize retesting efforts and delivery of pre-exposure prophylaxis (PrEP) to pregnant and postpartum women most at risk for HIV acquisition while minimizing unnecessary perinatal exposure.

METHODS

Data from women enrolled in a cross-sectional study of programmatic HIV retesting and/or receiving maternal and child health care services at five facilities in Western Kenya were used to validate the predictive ability of a simplified risk score previously developed for pregnant/postpartum women. Incident HIV infections were defined as new HIV diagnoses following confirmed negative or unknown status during pregnancy. Predictive performance was assessed using the area under the receiver operating characteristic curve (AUC) and Brier score.

RESULTS

Among 1266 women with 35 incident HIV infections, we found an AUC for predicting HIV acquisition of 0.60 (95% CI, 0.51, 0.69), with a Brier score of 0.27. A risk score >6 was associated with a 2.9-fold increase in the odds of HIV acquisition (95% CI, 1.48, 5.70; p = 0.002) vs scores ≤6. Women with risk scores >6 were 27% (346/1266) of the population but accounted for 52% of HIV acquisitions. Syphilis, age at sexual debut, and unknown partner HIV status were significantly associated with increased risk of HIV in this cohort.

CONCLUSION

The simplified risk score performed moderately at predicting risk of HIV acquisition in this population of pregnant and postpartum women and may be useful to guide PrEP use or counseling.

Data mining and machine learning in HIV infection risk research: An overview and recommendations

In the contemporary era, the applications of data mining and machine learning have permeated extensively into medical research, significantly contributing to areas such as HIV studies. By reviewing 38 articles published in the past 15 years, the study presents a roadmap based on seven different aspects, utilizing various machine learning techniques for both novice researchers and experienced researchers seeking to comprehend the current state of the art in this area. While traditional regression modeling techniques have been commonly used, researchers are increasingly adopting more advanced fully supervised machine learning and deep learning techniques, which often outperform the traditional methods in predictive performance. Additionally, the study identifies nine new open research issues and outlines possible future research plans to enhance the outcomes of HIV infection risk research. This review is expected to be an insightful guide for researchers, illuminating current practices and suggesting advancements in the field.

Identifying Individuals at High Risk for HIV and Sexually Transmitted Infections With an Artificial Intelligence-Based Risk Assessment Tool

Background

We have previously developed an artificial intelligence-based risk assessment tool to identify the individual risk of HIV and sexually transmitted infections (STIs) in a sexual health clinical setting. Based on this tool, this study aims to determine the optimal risk score thresholds to identify individuals at high risk for HIV/STIs.

Methods

Using 2008-2022 data from 216 252 HIV, 227 995 syphilis, 262 599 gonorrhea, and 320 355 chlamydia consultations at a sexual health center, we applied MySTIRisk machine learning models to estimate infection risk scores. Optimal cutoffs for determining high-risk individuals were determined using Youden's index.

Results

The HIV risk score cutoff for high risk was 0.56, with 86.0% sensitivity (95% CI, 82.9%-88.7%) and 65.6% specificity (95% CI, 65.4%-65.8%). Thirty-five percent of participants were classified as high risk, which accounted for 86% of HIV cases. The corresponding cutoffs were 0.49 for syphilis (sensitivity, 77.6%; 95% CI, 76.2%-78.9%; specificity, 78.1%; 95% CI, 77.9%-78.3%), 0.52 for gonorrhea (sensitivity, 78.3%; 95% CI, 77.6%-78.9%; specificity, 71.9%; 95% CI, 71.7%-72.0%), and 0.47 for chlamydia (sensitivity, 68.8%; 95% CI, 68.3%-69.4%; specificity, 63.7%; 95% CI, 63.5%-63.8%). High-risk groups identified using these thresholds accounted for 78% of syphilis, 78% of gonorrhea, and 69% of chlamydia cases. The odds of positivity were significantly higher in the high-risk group than otherwise across all infections: 11.4 (95% CI, 9.3-14.8) times for HIV, 12.3 (95% CI, 11.4-13.3) for syphilis, 9.2 (95% CI, 8.8-9.6) for gonorrhea, and 3.9 (95% CI, 3.8-4.0) for chlamydia.

Conclusions

Risk scores generated by the AI-based risk assessment tool MySTIRisk, together with Youden's index, are effective in determining high-risk subgroups for HIV/STIs. The thresholds can aid targeted HIV/STI screening and prevention.

Factors associated with the choice of having multiple sexual partners among male college students with casual heterosexual sex in Zhejiang Province, Eastern China

BACKGROUND

Young students infected with HIV have become a significant public health issue in China, this study aimed to understand the factors influencing the choice of having multiple sexual partners among male college students who had casual heterosexual sex in Zhejiang Province and to scientifically justify developing HIV/AIDS intervention strategies among them.

METHODS

A stratified cluster sampling method was used for the survey of students from 13 colleges or universities in Zhejiang Province between October and November 2018. The questionnaire collected information on general demographic characteristics, knowledge of HIV/AIDS prevention and treatment, sexual attitudes and risk awareness, sexual behavioural characteristics, and acceptance of interventions. The univariable and multivariable analyses were conducted in this study.

RESULTS

Study participants included 362 male college students who exhibited casual heterosexual sex and were aware of the number of sexual partners they had. Among them, 222 students engaged in casual heterosexual sex with multiple sexual partners (61.33%). The results of the multivariable analysis revealed several factors associated with male students' choice to have multiple sexual partners: monthly living expenses greater than or equal to 1501 CNY (adjusted OR = 2.24, 95% CI = 1.21-4.16), sexual behavior after consuming alcohol (adjusted OR = 2.19, 95% CI = 1.32-3.63), whose casual partner types were non-student (adjusted OR = 2.51, 95% CI = 1.45-4.22), and those who discussed using condoms during sexual intercourse (adjusted OR = 0.50, 95% CI = 0.28-0.89).

CONCLUSION

The choice to engage in casual heterosexual sex with multiple partners was found to be associated with several factors among male college students, including economic status, engaging in sexual behavior after consuming alcohol, the type of the casual partner, and using condoms. These findings highlight the significance of implementing targeted interventions and comprehensive sexual health education programs within college settings in order to encourage safer sexual practices among students.

Using HIV Risk Self-Assessment Tools to Increase HIV Testing in Men Who Have Sex With Men in Beijing, China: App-Based Randomized Controlled Trial

BACKGROUND

Men who have sex with men (MSM) in China hold a low-risk perception of acquiring HIV. This has resulted in an inadequate HIV testing rate.

OBJECTIVE

This study aims to investigate whether administering HIV risk self-assessments with tailored feedback on a gay geosocial networking (GSN) app could improve HIV testing rates and reduce sexual risk behaviors in Chinese MSM.

METHODS

We recruited MSM from Beijing, China, who used the GSN platform Blued in October 2017 in this 12-month double-blinded randomized controlled trial. From October 2017 to September 2018, eligible participants were randomly assigned to use a self-reported HIV risk assessment tool that provided tailored feedback according to transmission risk (group 1), access to the same HIV risk assessment without feedback (group 2), or government-recommended HIV education materials (control). All interventions were remotely delivered through the mobile phone-based app Blued, and participants were followed up at 1, 3, 6, and 12 months from baseline. The number of HIV tests over the 12-month study was the primary outcome and was assessed using an intention-to-treat analysis with an incident rate ratio (IRR). Unprotected anal intercourse (UAI) over 6 months was assessed by a modified intention-to-treat analysis and was the secondary outcome. All statistical analyses were conducted in SAS 9.3 (SAS Institute, Inc.), and a P value <.05 was considered statistically significant.

RESULTS

In total, 9280 MSM were recruited from baseline and were randomly assigned to group 1 (n=3028), group 2 (n=3065), or controls (n=3187). After follow-up, 1034 (34.1%), 993 (32.4%), and 1103 (34.6%) remained in each group, respectively. Over 12 months, group 1 took 391 tests (mean of 2.51 tests per person), group 2 took 352 tests (mean of 2.01 tests per person), and controls took 295 tests (mean of 1.72 tests per person). Group 1 had significantly more HIV testing than the control group (IRR 1.32, 95% CI 1.09-4.58; P=.01), while group 2 did not differ significantly from the controls (IRR 1.06, 95% CI 0.86-1.30; P=.60). The proportion of UAI was not statistically different among different groups, but all 3 groups had UAI, which declined from baseline.

CONCLUSIONS

Repeated HIV risk assessments coupled with tailored feedback through GSN apps improved HIV testing. Such interventions should be considered a simple way of improving HIV testing among MSM in China and increasing awareness of HIV status.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03320239; https://clinicaltrials.gov/study/NCT03320239.

Preexposure Prophylaxis for the Prevention of HIV: Updated Evidence Report and Systematic Review for the US Preventive Services Task Force

Importance

A 2019 review for the US Preventive Services Task Force (USPSTF) found oral preexposure prophylaxis (PrEP) associated with decreased HIV infection risk vs placebo or no PrEP in adults at increased HIV acquisition risk. Newer PrEP regimens are available.

Objective

To update the 2019 review on PrEP, to inform the USPSTF.

Data Sources

Ovid MEDLINE, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, and Embase (January 2018 to May 16, 2022); surveillance through March 24, 2023.

Study Selection

Randomized clinical trials of PrEP vs placebo or no PrEP or newer vs older PrEP regimens and diagnostic accuracy studies of instruments for predicting incident HIV infection.

Data Extraction and Synthesis

Dual review of titles and abstracts, full-text articles, study quality, and data abstraction. Data were pooled using the DerSimonian and Laird random-effects model.

Main Outcomes and Measures

HIV acquisition, mortality, and harms; and diagnostic test accuracy.

Results

Thirty-two studies were included in the review (20 randomized clinical trials [N = 36 543] and 12 studies of diagnostic accuracy [N = 5 544 500]). Eleven trials in the 2019 review found oral PrEP associated with decreased HIV infection risk vs placebo or no PrEP (n = 18 172; relative risk [RR], 0.46 [95% CI, 0.33-0.66]). Higher adherence was associated with greater efficacy. One new trial (n = 5335) found oral tenofovir alafenamide/emtricitabine (TAF/FTC) to be noninferior to tenofovir disoproxil fumarate/emtricitabine (TDF/FTC) in men who have sex with men (RR, 0.47 [95% CI, 0.19-1.14]). Two new trials found long-acting injectable cabotegravir associated with decreased risk of HIV infection vs oral TDF/FTC (RR, 0.33 [95% CI, 0.18-0.62] in cisgender men who have sex with men and transgender women [n = 4490] and RR, 0.11 [95% CI, 0.04-0.31] in cisgender women [n = 3178]). Discrimination of instruments for predicting incident HIV infection was moderate in men who have sex with men (5 studies; n = 25 488) and moderate to high in general populations of persons without HIV (2 studies; n = 5 477 291).

Conclusions and Relevance

In adults at increased HIV acquisition risk, oral PrEP was associated with decreased risk of acquiring HIV infection compared with placebo or no PrEP. Oral TAF/FTC was noninferior to oral TDF/FTC, and injectable cabotegravir reduced the risk of HIV infection compared with oral TDF/FTC in the populations studied.

Disjuncture between self-perceived and clinically assessed risk of HIV among gay, bisexual, and other men who have sex with men in Ontario and British Columbia, Canada

BACKGROUND

Self-perceived and clinically assessed HIV risk do not always align. We compared self-perceived and clinically assessed risk of HIV and the reasons for self-perceived low risk of HIV among gay, bisexual, and other men who have sex with men (GBM) from large urban centers in Ontario and British Columbia, Canada.

METHODS

Never PrEP users recruited from sexual health clinics or online, completed a cross-sectional survey between July/2019 and August/2020. We contrasted self-perceived HIV risk against criteria from the Canadian PrEP guidelines and participants were categorized as concordant or discordant. We used content analysis to categorize participants' free-text explanations for perceived low HIV risk. These were compared with answers to quantitative responses about condomless sex acts and number of partners.

RESULTS

Of 315 GBM who self-perceived low risk of HIV, 146 (46%) were considered at high risk according to the guidelines. Participants with discordant assessment were younger, had less years of formal education, were more often in an open relationship and were more likely to self-identify as gay. Reasons for self-perceived low HIV risk in the discordant group were condom use (27%), being in a committed relationship/having one main partner (15%), having no or infrequent anal sex (12%) and having few partners (10%).

CONCLUSIONS

There is a disjuncture between self-perceived and clinically assessed risk of HIV. Some GBM may underestimate their HIV risk and clinical criteria may overestimate risk. Bridging these gaps requires efforts to increase HIV risk awareness in the community, and refinement of clinical assessments based on individualized discussions between the provider and the user.

Correlates of condom use among male university students from eastern China who engage in casual sex

Consistent condom use with casual partners is critical for preventing the transmission of human immunodeficiency virus (HIV) among male university students. This study aimed to determine the level of consistent condom use and explore the correlates of condom use consistency in male university students in eastern China. A descriptive cross-sectional survey was conducted in 13 universities in Zhejiang Province, which involved the recruitment of 31,674 students by stratified random sampling. Among them, 545 male students who engaged in casual sex in the year prior to this study were included. Adjusted and unadjusted logistic regression models were used to examine the correlates associated with consistent condom use. Among the 545 male university students, only 205 (37.6%) consistently used condoms in the previous year. The following correlates were associated with higher rates of consistent condom use: 1) Knowledge, specifically, the number of correct answers to "HIV infection can be determined by appearance" (AOR: 2.06, 95% CI: 1.21-3.49); 2) never finding casual partners on the internet during the past over the prior year (AOR: 0.63; 95% CI: 0.40-0.99); 3) never drinking alcohol before casual sex during the last over the prior year (AOR: 0.30; 95% CI: 0.20-0.46); 4) never engaging in commercial sex (AOR: 0.57; 95% CI: 0.34-0.96); and 5) high condom self-efficacy score (AOR: 2.55; 95% CI: 1.44-4.49). The study found a low level of consistent condom use among male university students. Promoting condom self-efficacy, reducing web-based casual sex, drinking before sex, and commercial sex are essential to improving the level of consistent condom use among male university students to reduce the transmission of HIV.

Performance of HIV Infection Prediction Models in Men Who Have Sex with Men: A Systematic Review and Meta-Analysis

Effective ways to identify and predict men who have sex with men (MSM) at substantial risk for HIV is a global priority. HIV risk assessment tools can improve individual risk awareness and subsequent health-seeking actions. We sought to identify and characterize the performance of HIV infection risk prediction models in MSM through systematic review and meta-analysis. PubMed, Embase, and The Cochrane Library were searched. Eighteen HIV infection risk assessment models with a total of 151,422 participants and 3643 HIV cases were identified, eight of which have been externally validated by at least one study (HIRI-MSM, Menza Score, SDET Score, Li Model, DHRS, Amsterdam Score, SexPro model, and UMRSS). The number of predictor variables in each model ranged from three to 12, age, the number of male sexual partners, unprotected receptive anal intercourse, recreational drug usage (amphetamines, poppers), and sexually transmitted infections were critical scoring variables. All eight externally validated models performed well in terms of discrimination, with the pooled area under the receiver operating characteristic curve (AUC) ranging from 0.62 (95%CI: 0.51 to 0.73, SDET Score) to 0.83 (95%CI: 0.48 to 0.99, Amsterdam Score). Calibration performance was only reported in 10 studies (35.7%, 10/28). The HIV infection risk prediction models showed moderate-to-good discrimination performance. Validation of prediction models across different geographic and ethnic environments is needed to ensure their real-world application.

Predicting the risk of HIV infection among internal migrant MSM in China: An optimal model based on three variable selection methods

Introduction

Internal migrant Men who have sex with men (IMMSM), which has the dual identity of MSM and floating population, should be more concerned among the vulnerable groups for HIV in society. Establishing appropriate prediction models to assess the risk of HIV infection among IMMSM is of great significance to against HIV infection and transmission.

Methods

HIV and syphilis infection were detected using rapid test kits, and other 30 variables were collected among IMMSM through questionnaire. Taking HIV infection status as the dependent variable, three methods were used to screen predictors and three prediction models were developed respectively. The Hosmer-Lemeshow test was performed to verify the fit of the models, and the net classification improvement and integrated discrimination improvement were used to compare these models to determine the optimal model. Based on the optimal model, a prediction nomogram was developed as an instrument to assess the risk of HIV infection among IMMSM. To quantify the predictive ability of the nomogram, the C-index measurement was performed, and internal validation was performed using bootstrap method. The receiver operating characteristic (ROC) curve, calibration plot and dynamic component analysis (DCA) were respectively performed to assess the efficacy, accuracy and clinical utility of the prediction nomogram.

Results

In this study, 12.52% IMMSMs were tested HIV-positive and 8.0% IMMSMs were tested syphilis-positive. Model A, model B, and model C fitted well, and model B was the optimal model. A nomogram was developed based on the model B. The C-index of the nomogram was 0.757 (95% CI: 0.701-0.812), and the C-index of internal verification was 0.705.

Conclusions

The model established by stepwise selection methods incorporating 11 risk factors (age, education, marriage, monthly income, verbal violence, syphilis, score of CUSS, score of RSES, score of ULS, score of ES and score of DS) was the optimal model that achieved the best predictive power. The risk nomogram based on the optimal model had relatively good efficacy, accuracy and clinical utility in identifying internal migrant MSM at high-risk for HIV infection, which is helpful for developing targeted intervention for them.

Sexual behaviour changes and HIV infection among men who have sex with men: evidence from an open cohort in China

BACKGROUND

The HIV epidemic in key populations such as men who have sex with men (MSM) is a public health issue of worldwide concern. China has seen an increase in newly diagnosed HIV infections through male-male sexual contact in the past decade. In a long-term cohort, how the complex behaviour pattern of MSM changed and the association with the HIV risk are unclear at present.

METHODS

This study was conducted from October 2011 to December 2019 in Tianjin. MSM were recruited by snowball sampling through online and offline ways. Demographic and sexual behavioural data were collected for analysis. Three indicators (condom use in last anal sex, frequency of condom use during anal sex and the number of sexual partners) were used to define the behaviour change. Participants with zero, one, and two or three risk indicators were categorised into behaviour types of 'protective', 'moderate', and 'fragile', respectively. Change in behaviour type between baseline and each visit was considered. Time-varying Cox models were performed to evaluate HIV infection risk.

RESULTS

Of 2029 MSM included in the study, 127 were new HIV diagnoses. The overall incidence rate was 3.36 per 100 person-years. The percentage of 'protective' and 'moderate' behaviour types had a conspicuous growth trend as the follow-up. Furthermore, the HIV incidence rate in each visit among different behaviour transition types showed a general downward trend as the number of total follow-up times increased. Individuals who remained in 'fragile' (adjusted HR (aHR): 25.86, 95% CI: 6.92 to 96.57) or changed from 'protective' to 'moderate' (aHR: 4.79, 95% CI: 1.18 to 19.47), 'protective' to 'fragile' (aHR: 23.03, 95% CI: 6.02 to 88.13), and 'moderate' to 'fragile' (aHR: 25.48, 95% CI: 6.79 to 95.40) between baseline and the last follow-up had a higher HIV risk. Gained risk indicators were associated with the increase of HIV risk (gained one indicator, aHR: 2.67, 95% CI: 1.68 to 4.24; gained two or three indicators, aHR: 4.99, 95% CI: 3.00 to 8.31) while losing just one risk indicator could halve the risk (aHR: 0.43, 95% CI: 0.21 to 0.90).

CONCLUSIONS

Among MSM in Tianjin, it is necessary to get timely behaviour change for those with high-incidence behaviour patterns while sustaining for those with low-incidence patterns.

TRIAL REGISTRATION NUMBER

Chinese Clinical Trials Registry (ChiCTR2000039500).

Application of machine learning algorithms in predicting HIV infection among men who have sex with men: Model development and validation

Background

Continuously growing of HIV incidence among men who have sex with men (MSM), as well as the low rate of HIV testing of MSM in China, demonstrates a need for innovative strategies to improve the implementation of HIV prevention. The use of machine learning algorithms is an increasing tendency in disease diagnosis prediction. We aimed to develop and validate machine learning models in predicting HIV infection among MSM that can identify individuals at increased risk of HIV acquisition for transmission-reduction interventions.

Methods

We extracted data from MSM sentinel surveillance in Zhejiang province from 2018 to 2020. Univariate logistic regression was used to select significant variables in 2018-2019 data (P < 0.05). After data processing and feature selection, we divided the model development data into two groups by stratified random sampling: training data (70%) and testing data (30%). The Synthetic Minority Oversampling Technique (SMOTE) was applied to solve the problem of unbalanced data. The evaluation metrics of model performance were comprised of accuracy, precision, recall, F-measure, and the area under the receiver operating characteristic curve (AUC). Then, we explored three commonly-used machine learning algorithms to compare with logistic regression (LR), including decision tree (DT), support vector machines (SVM), and random forest (RF). Finally, the four models were validated prospectively with 2020 data from Zhejiang province.

Results

A total of 6,346 MSM were included in model development data, 372 of whom were diagnosed with HIV. In feature selection, 12 variables were selected as model predicting indicators. Compared with LR, the algorithms of DT, SVM, and RF improved the classification prediction performance in SMOTE-processed data, with the AUC of 0.778, 0.856, 0.887, and 0.942, respectively. RF was the best-performing algorithm (accuracy = 0.871, precision = 0.960, recall = 0.775, F-measure = 0.858, and AUC = 0.942). And the RF model still performed well on prospective validation (AUC = 0.846).

Conclusion

Machine learning models are substantially better than conventional LR model and RF should be considered in prediction tools of HIV infection in Chinese MSM. Further studies are needed to optimize and promote these algorithms and evaluate their impact on HIV prevention of MSM.

Risk-Based Screening Tools to Optimise HIV Testing Services: a Systematic Review

PURPOSE OF REVIEW

Effective ways to diagnose the remaining people living with HIV who do not know their status are a global priority. We reviewed the use of risk-based tools, a set of criteria to identify individuals who would not otherwise be tested (screen in) or excluded people from testing (screen out).

RECENT FINDINGS

Recent studies suggest that there may be value in risk-based tools to improve testing efficiency (i.e. identifying those who need to be tested). However, there has not been any systematic reviews to synthesize these studies. We identified 18,238 citations, and 71 were included. The risk-based tools identified were most commonly from high-income (51%) and low HIV (<5%) prevalence countries (73%). The majority were for "screening in" (70%), with the highest performance tools related to identifying MSM with acute HIV. Screening in tools may be helpful in settings where it is not feasible or recommended to offer testing routinely. Caution is needed for screening out tools, where there is a trade-off between reducing costs of testing with missing cases of people living with HIV.

Prediction Model for the Risk of HIV Infection among MSM in China: Validation and Stability

The impact of psychosocial factors on increasing the risk of HIV infection among men who have sex with men (MSM) has attracted increasing attention. We aimed to develop and validate an integrated prediction model, especially incorporating emerging psychosocial variables, for predicting the risk of HIV infection among MSM. We surveyed and collected sociodemographic, psychosocial, and behavioral information from 547 MSM in China. The participants were split into a training set and a testing set in a 3:1 theoretical ratio. The prediction model was constructed by introducing the important variables selected with the least absolute shrinkage and selection operator (LASSO) regression, applying multivariate logistic regression, and visually assessing the risk of HIV infection through the nomogram. Receiver operating characteristic curves (ROC), Kolmogorov–Smirnov test, calibration plots, Hosmer–Lemeshow test and population stability index (PSI) were performed to test validity and stability of the model. Four of the 15 selected variables—unprotected anal intercourse, multiple sexual partners, involuntary subordination and drug use before sex—were included in the prediction model. The results indicated that the comprehensive prediction model we developed had relatively good predictive performance and stability in identifying MSM at high-risk for HIV infection, thus providing targeted interventions for high-risk MSM.

Risk factors for HIV infection among men who have sex with men in the ANRS IPERGAY PrEP trial

OBJECTIVES

We aimed to assess among men who have sex with men (MSM) risk factors for HIV infection, to identify those who require urgent pre-exposure prophylaxis (PrEP) prescription.

METHODS

All participants enrolled in the placebo arm of the ANRS IPERGAY trial, or infected between screening and day 0, were included. Baseline characteristics were described and HIV incidence rate ratios (RRs) were estimated with their 95% CIs.

RESULTS

203 MSM were included with a median follow-up of 9 months. During the study period, 16 participants acquired HIV infection while not receiving tenofovir disoproxil and emtricitabin (TDF/FTC) over 212.4 person-years (PYs) of follow-up (incidence rate 7.5/100 PYs, 95% CI: 4.3 to 12.2). Being enrolled in Paris was associated with a significant increased risk of HIV infection (RR: 4.1; 95% CI: 1.1 to 28.3). A high number of sexual partners in prior 2 months (≥10 vs <5) and of condomless receptive anal sex episodes in prior 12 months (>5 vs <5) were strong predictors for HIV acquisition (RR: 10.6 (2 to 260.2) and 3.3 (1.2 to 10.2), respectively). Those who reported more often or only receptive sexual practices were also at increased risk (RR: 9.8 (2.0 to 246.6)). The use of recreational drugs in prior 12 months, especially gamma hydroxybutarate/gamma butyrolactone (RR: 5.9; 95% CI: 2 to 21.7), was associated with a significantly increased risk of HIV acquisition even after adjustment for sexual practices.

CONCLUSIONS

MSM who have frequent condomless receptive anal sex and multiple partners, or use recreational drugs should be targeted in priority for PrEP prescription especially if they live in an area with a high prevalence of HIV infection.

A simple algorithm for selecting cases to investigate acute and early HIV infections in low- and middle-income countries

We documented the outcome of an over 10-year (2011-2021) effort to diagnose acute and early HIV infections (AEHI) in an Infectious Diseases Outpatient Clinic with limited resources. Of a total of 132, 119 HIV-RNA tests were performed from 2017 to 2020, 12 cases were identified, using a simple algorithm: risk exposure of 6 weeks or less before the visit and/or symptoms compatible with acute retroviral syndrome 7-30 days after exposure and/or undetermined 3rd generation rapid diagnostic test or serology. AEHI diagnoses varied from 2.4% among asymptomatic to 25% for undetermined serology cases using this simple screening applicable to different settings.

Derivation of an HIV Risk Score for African Women Who Engage in Sex Work

No tool exists to stratify HIV risk in contemporary African female sex worker (FSW) populations. Data from a cohort of HIV-negative FSWs in Mombasa, Kenya from 2010 to 2017 were used to conduct a survival analysis assessing predictors of HIV infection. Stepwise regression was used to construct a multivariable model that formed the basis for the score. Seventeen HIV infections occurred over 1247 person-years of follow-up contributed by 670 women. Using depot medroxyprogesterone acetate (DMPA), having a curable sexually transmitted infection (STI), and being married contributed points to the score. HIV incidence was 0.85/100 person-years in a lower-risk group and 3.10/100 person-years in a higher-risk group. In a cohort with overall HIV incidence < 1.50/100 person-years, this risk score identified a subgroup of FSWs with HIV incidence > 3.00/100 person-years, which is the threshold used by the World Health Organization for initiating pre-exposure prophylaxis (PrEP). If validated in an external population, this tool could be useful for targeted PrEP promotion among higher-risk FSWs.

Can We Predict Incorrect PrEP Use in High HIV Risk Situations Among Men Who Have Sex With Men? An Analysis of Be-PrEP-ared, the Belgian PrEP Demonstration Study

BACKGROUND

Pre-exposure prophylaxis (PrEP) efficacy for HIV prevention is highly correlated with the degree of adherence. The objective of this analysis was to identify PrEP users who did not correctly take their dose in high HIV exposure situations and to explore potential predictors of this behavior.

METHODS

Study participants completed a personal Web-based diary during their entire follow-up, providing daily information on pill intake and sexual activity. They also completed a sociobehavioral questionnaire. The association between the number of unprotected high HIV exposure sex days (as a measure for suboptimal adherence) and potential predicting factors was examined using a logistic regression, followed by a negative binomial regression model. We also constructed a risk index score for predicting poor adherence.

RESULTS

A total of 40.8% of participants did not correctly use PrEP in at least one situation of high HIV exposure during follow-up. Not having a HIV-negative steady partner, reporting more than 10 occasional or more than 10 anonymous partners, using chemsex drugs, receiving money for sex, and a history of more than one sexually transmitted infection were significantly associated with unprotected high HIV exposure sex. The risk index score yielded a poor discriminative power (area under the curve 0.62 and 0.64).

CONCLUSIONS

We observed a high proportion of suboptimal adherence. Even if none of the participants acquired HIV during the study, tailored adherence support is needed to specific men who have sex with men such as those taking chemsex drugs and those engaging in paid sex.

Analysis of homosexual behavior characteristics and influencing factors of male college students in Zhejiang Province

The purpose of this study was to understand the homosexual behavior characteristics and influencing factors of male college students and to provide scientific evidence for the prevention of HIV infection in college students.A self-made online questionnaire was used to collect information on demographic characteristics, sexual attitudes, sexual behaviors, and interventions of the respondents. The χ2 test was performed on the constituent ratios of different groups, and whether homosexual behavior occurred was the dependent variable. Logistic regression was subsequently used to analyze the influencing factors of male homosexual behavior.A total of 2665 students were surveyed, including 219 men who have sex with men, accounting for 8.22% of the sample population. Multivariate analysis revealed the following independent influencing factors of homosexual behavior among male college students: the student's household registration was Zhejiang Province, the hometown was in the city, accepted male homosexual sex, had temporary sex in the last year, and awareness that the correct use of condoms can reduce the spread and risk of acquired immunodeficiency syndrome.Various measures should be enacted to promote human immunodeficiency virus/acquired immunodeficiency syndrome education and intervention among college students, especially emphasizing making friends and advocating safe sex to prevent the spread of the disease.

Peer Mobilization and Human Immunodeficiency Virus (HIV) Partner Notification Services Among Gay, Bisexual, and Other Men Who Have Sex With Men and Transgender Women in Coastal Kenya Identified a High Number of Undiagnosed HIV Infections

Background

Human immunodeficiency virus (HIV) partner notification services (HPN), peer mobilization with HIV self-testing, and acute and early HIV infection (AEHI) screening among gay, bisexual, and other men who have sex with men (GBMSM) and transgender women (TGW) were assessed for acceptability, feasibility, and linkage to antiretroviral therapy (ART) and preexposure prophylaxis (PrEP) services.

Methods

Between April and August 2019, peer mobilizers mobilized clients by offering HIV oral self-tests and immediate clinic referral for clients with AEHI symptoms. Mobilized participants received clinic-based rapid antibody testing and point-of-care HIV RNA testing. Newly diagnosed participants including those derived from HIV testing services were offered immediate ART and HPN. Partners were recruited through HPN.

Results

Of 772 mobilized clients, 452 (58.5%) enrolled in the study as mobilized participants. Of these, 16 (3.5%) were HIV newly diagnosed, including 2 (0.4%) with AEHI. All but 2 (14/16 [87.5%]) initiated ART. Thirty-five GBMSM and TGW were offered HPN and 27 (77.1%) accepted it. Provider referral identified a higher proportion of partners tested (39/64 [60.9%] vs 5/14 [35.7%]) and partners with HIV (27/39 [69.2%] vs 2/5 [40.0%]) than index referral. Of 44 enrolled partners, 10 (22.7%) were newly diagnosed, including 3 (6.8%) with AEHI. All 10 (100%) initiated ART. PrEP was initiated among 24.0% (103/429) mobilized participants and 28.6% (4/14) partners without HIV.

Conclusions

HPN, combined with a peer mobilization-led self-testing strategy and AEHI screening for GBMSM and TGW, appears to be acceptable and feasible. These strategies, especially HPN provider referral, effectively identified undiagnosed HIV infections and linked individuals to ART and PrEP services.

Constructions of HIV Risk Among a Diverse Sample of HIV-Negative Young Men Who Have Sex With Men Who Are Repeat Testers

INTRODUCTION

To end the HIV epidemic, HIV prevention and pre-exposure prophylaxis (PrEP) promotion efforts must reach young men who have sex with men (YMSM) at greatest risk for HIV. This study qualitatively explored whether common metrics used by clinicians, scientists, and public health officials to objectively assess HIV risk align with how YMSM conceptualize their risk for HIV and the factors that shape YMSM's risk perceptions.

METHODS

Interviews with a racially/ethnically diverse sample of HIV-negative YMSM (ages 19-24 years, 60% Latinx; n = 20) examined conceptualizations of HIV risk within the context of repeat HIV testing. Iterative, applied thematic analysis examined how participants conceptualized and constructed their HIV risk, and compared participants' descriptions of their risk with a validated quantitative assessment of HIV risk that reliably predicts HIV seroconversion in this group.

RESULTS

Objective quantitative assessments of HIV risk poorly aligned with participants' perceived HIV risk. Participants described their current risk in relative terms (relative to past risk and relative to friends'/peers' risk) and described age/developmental stage and changes in knowledge about HIV prevention as key factors in risk changes over time. Other factors included substance use and trust/mistrust in sexual partners and scientific advances in HIV prevention (eg, U = U and PrEP). Factors that influenced participants' perceived HIV risk were similar regardless of objective risk assessment.

CONCLUSIONS

Quantitative assessments of risk may poorly align with risk perception among YMSM. Although objective metrics can effectively target YMSM at greatest risk for HIV transmission, interventions to improve prevention behaviors and PrEP uptake may be more effective when tailored to bridge the disconnection between objective HIV risk assessments and YMSM's constructions of risk.

Derivation and Validation of an HIV Risk Prediction Score Among Gay, Bisexual, and Other Men Who Have Sex With Men to Inform PrEP Initiation in an STD Clinic Setting

BACKGROUND

Clinicians and health departments would ideally undertake targeted efforts to promote HIV pre-exposure prophylaxis (PrEP) and frequent HIV testing using data-based criteria to identify populations at elevated risk for HIV. We developed an HIV risk prediction score for men who have sex with men (MSM) to identify individuals at substantial risk for HIV acquisition.

METHODS

We created a retrospective cohort of MSM who tested HIV-negative at the sexually transmitted disease clinic in Seattle, WA, from 2001 to 2015, and identified seroconversions using HIV surveillance data. We split the cohort randomly 2:1 into derivation and validation data sets, and used Cox proportional hazards to estimate the hazard of acquiring HIV associated with behavioral and clinical predictors, and the Akaike information criterion to determine which variables to retain in our model.

RESULTS

Among 16,448 MSM, 640 seroconverted over a 14.3-year follow-up period. The best prediction model included 13 variables and had an area under the receiver operating characteristic curve of 0.73 (95% confidence interval: 0.71 to 0.76), 76% sensitivity, and 63% specificity at a score cutoff ≥11. A simplified model restricted to 2011-2015 included 4 predictors [methamphetamine use, condomless receptive anal intercourse (CRAI), ≥10 partners, and current diagnosis or self-reported gonorrhea/syphilis in the past year]. This model, the Seattle PrEP Score, had an area under the receiver operating characteristic curve of 0.69 (95% confidence interval: 0.64 to 0.73), 62% sensitivity, and 70% specificity. One-year incidence was 0.5% for a score of 0, 0.7% for a score of 1, and 2.1% for scores ≥2.

CONCLUSIONS

The Seattle PrEP Score was predictive of HIV acquisition and could help clinicians and public health agencies identify MSM who could benefit from PrEP and frequent HIV testing.

Age-Specific Risk Scores Do Not Improve HIV-1 Prediction Among Women in South Africa

Supplemental Digital Content is Available in the Text.

HIV-1 risk scoring tools could help target provision of prevention modalities such as pre-exposure prophylaxis. Recent research suggests that risk scores for women aged 18–45 may not predict risk well among young women aged 18–24. We evaluated the predictive performance of age-specific risk scores compared with the existing non–age-specific VOICE risk score, developed for women aged 18–45.

Effective HIV Molecular Surveillance Requires Identification of Incident Cases of Infection

BACKGROUND

Ending the HIV epidemic requires knowledge of key drivers of spread of HIV infection.

METHODS

Between 1996 and 2018, 1119 newly and previously diagnosed, therapy-naïve persons with HIV (PWH) from San Diego were followed. A genetic distance-based network was inferred using pol sequences, and genetic clusters grew over time through linkage of sequences from newly observed infections. Cox proportional hazards models were used to identify factors associated with the rate of growth. These results were used to predict the impact of a hypothetical intervention targeting PWH with incident infection. Comparison was made to the CDC EHE molecular surveillance strategy, which prioritizes clusters recently linked to all new HIV diagnoses and does not incorporate data on incident infections.

RESULTS

Overall, 219 genetic linkages to incident infections were identified over a median follow-up of 8.8 years. Incident cluster growth was strongly associated with proportion of PWH in the cluster who themselves had incident infection. (HR 44.09; 95% CI: 17.09, 113.78). The CDC EHE molecular surveillance strategy identified 11 linkages to incident infections a genetic distance threshold of 0.5%, and 24 linkages at 1.5%.

CONCLUSIONS

Over the past two decades, incident infections drove incident HIV cluster growth in San Diego. The current CDC EHE molecular detection and response strategy would not have identified most transmission events arising from those with incident infection in San Diego. Molecular surveillance that includes detection of incident cases will provide a more effective strategy for EHE.

Patient-Led Decision-Making for HIV Preexposure Prophylaxis

PURPOSE OF REVIEW

Shared decision-making is a process that involves bidirectional exchange of information between patients and providers to support patients in making individualized, evidence-based decisions about their healthcare. We review the evidence on patient-led decision-making, a form of shared decision-making that maximizes patient autonomy, as a framework for decisions about HIV preexposure prophylaxis (PrEP). We also assess the likelihood that patient-led decision-making occurs for PrEP and describe interventions to facilitate this process.

RECENT FINDINGS

Patient-led decision-making is likely to be uncommon for PrEP, in part because healthcare providers lack knowledge and training about PrEP. Few evidence-based interventions exist to facilitate patient-led decision-making for PrEP. There is a need for rigorously developed interventions to increase knowledge of PrEP among patients and healthcare providers and support patient-led decision-making for PrEP, which will be increasingly important as the range of available PrEP modalities expands.

Estimating the percentage of European MSM eligible for PrEP: insights from a bio-behavioural survey in thirteen cities

OBJECTIVES

This paper aims to estimate the percentage of European men who have sex with men (MSM) who may benefit from pre-exposure prophylaxis (PrEP), applying the three most widely used HIV risk indices for MSM (MSM Risk Index, Menza score, San Diego Early Test (SDET) score) and drawing on a large-scale multisite bio-behavioural survey (Sialon II).

METHODS

The Sialon II study was a bio-behavioural survey among MSM implemented in 13 European cities using either time-location sampling or respondent-driven sampling. Biological and behavioural data from 4901 MSM were collected. Only behavioural data of HIV-negative individuals were considered. Three widely used risk indices to assess HIV acquisition risk among MSM were used to estimate individual HIV risk scores and PrEP eligibility criteria.

RESULTS

4219 HIV-negative MSM were considered. Regardless the HIV risk score used and the city, percentages of MSM eligible for PrEP were found to range between 5.19% and 73.84%. Overall, the MSM Risk Index and the Menza score yielded broadly similar percentages, whereas the SDET Index provided estimates constantly lower across all cities. Although all the three scores correlated positively (r>0.6), their concordance was highly variable (0.01<CCC<0.62).

CONCLUSION

Our findings showed the impact of different scoring systems on the estimation of the percentage of MSM who may benefit from PrEP in European cities. Although our primary aim was not to compare the performance of different HIV risk scores, data show that a considerable percentage of MSM in each city should be offered PrEP in order to reduce HIV infections. As PrEP is highly effective at preventing HIV among MSM, our findings provide useful, practical guidance for stakeholders in implementing PrEP at city level to tackle HIV infections in Europe.

Go Where the Virus Is: An HIV Micro-epidemic Control Approach to Stop HIV Transmission

Essentially all HIV transmission is from people living with HIV who are not virally suppressed. An HIV micro-epidemic control approach that differentiates treatment support and prevention services for people living with HIV and their network members according to viral burden could optimize the impact of epidemic control efforts.

Assessing the performance of international pre-exposure prophylaxis (PrEP) eligibility guidelines in a cohort of Chinese MSM, Beijing, China 2009 to 2016

INTRODUCTION

PrEP is a powerful HIV prevention tool, and locally relevant eligibility criteria are necessary to optimize the prevention impact of PrEP. We assessed performance of existing national and international PrEP eligibility criteria to predict future HIV seroconversion among MSM in Beijing, China.

METHODS

Participants were MSM aged ≥18 years who enrolled in a cohort study between July 2009 and March 2016. Participants completed HIV testing, syphilis testing, and a questionnaire on recent sexual health behaviours at each follow-up visit and were followed until HIV seroconversion or dropout. We assessed PrEP eligibility at the most recent follow-up visit prior to the final study visit. Participants were classified as indicated for PrEP (or not) based on criteria from guidelines from Europe, Korea, South Africa, Taiwan, the United Kingdom, United States and the World Health Organization. To compare guideline performance, we calculated sensitivity, specificity, Youden's Index (YI), Matthew's Correlation Coefficient (MCC), F1 scores and diagnostic odds ratios. For each guideline, performance measures were compared to random allocation of PrEP by randomly selecting a proportion of participants equal to the proportion indicated.

RESULTS

There were 287 (17∙3%) incident HIV seroconversions among 1663 MSM. The number of men indicated for PrEP from different guidelines ranged from 556 (33∙4%) to 1569 (94∙2%). Compared to random allocation, sensitivity of algorithms to predict seroconversion ranged from slightly worse (-4∙7%) to 30∙2% better than random. However, in absolute terms, none of the sensitivity values increased by more than 11% when compared to random allocation. For all guidelines, specificity was not meaningfully better than random allocation. No guidelines had high binary classification performance measures.

CONCLUSIONS

The performance of international indication guidelines in this sample was only slightly better than random allocation. Using such guidelines to screen out MSM self-identifying as interested in PrEP could lead to misallocation of resources and to good candidates for PrEP being denied access. For settings in which international guidelines perform poorly, alternative indication approaches should be considered.

Risk assessment and identification of HIV infection among men who have sex with men: a cross-sectional study in Southwest China

OBJECTIVES

The HIV epidemic is around 7%-20% among men who have sex with men (MSM) in Southwest China. The low HIV-testing rate highlights the need for tools to identify high-risk MSM in resource-limited regions. Our aim was, therefore, to evaluate the HIV RISK Assessment Tool for HIV prediction and to characterise the primary infection among MSM in Southwest China.

DESIGN

A cross-sectional survey was conducted in Guizhou province between January and December 2018. Participants were recruited from gay communities, among whom the HIV RISK Assessment Tool was evaluated. Logistic regression was used to analyse items associated with HIV and the area under the curve (AUC) of the receiver operating curve was calculated to quantify discrimination performance.

PARTICIPANTS

1330 MSM participants, of which 83 (6.2%) tested as HIV positive.

RESULTS

A higher composite score of the tool (adjusted OR (aOR) 9.33, 95% CI 4.57 to 19.05) was independently associated with HIV infection. Items positively associated with HIV infection included having 2-5 same sex partners (aOR 2.43, 95% CI 1.28 to 4.64), always (aOR 5.93, 95% CI 1.59 to 22.13) or sometimes (aOR 4.25, 95% CI 2.09 to 8.64) having unprotected anal intercourse, taking both insertive and receptive sex roles (aOR 4.95, 95% CI 2.57 to 9.53) or only the receptive sex role (aOR 2.26, 95% CI 1.21 to 4.24). The tool showed an optimal discrimination ability (AUC=0.827), with a specificity of 0.747 and sensitivity of 0.785. Five MSM were identified with primary infection and had similar sexual risk behaviors as HIV-positive participants.

CONCLUSIONS

The HIV RISK Assessment Tool showed an overall good performance in predicting HIV risk among MSM in Guizhou province where the prevalence is still severe. This tool also demonstrated a potential to identify primary infection and is worth being promoted in resource-limited regions.

Predicting the diagnosis of HIV and sexually transmitted infections among men who have sex with men using machine learning approaches

OBJECTIVES

We aimed to develop machine learning models and evaluate their performance in predicting HIV and sexually transmitted infections (STIs) diagnosis based on a cohort of Australian men who have sex with men (MSM).

METHODS

We collected clinical records of 21,273 Australian MSM during 2011-2017. We compared accuracies for predicting HIV and STIs (syphilis, gonorrhoea, chlamydia) diagnosis using four machine learning approaches against a multivariable logistic regression (MLR) model.

RESULTS

Machine learning approaches consistently outperformed MLR. Gradient boosting machine (GBM) achieved the highest area under the receiver operator characteristic curve for HIV (76.3%) and STIs (syphilis, 85.8%; gonorrhoea, 75.5%; chlamydia, 68.0%), followed by extreme gradient boosting (71.1%, 82.2%, 70.3%, 66.4%), random forest (72.0%, 81.9%, 67.2%, 64.3%), deep learning (75.8%, 81.0%, 67.5%, 65.4%) and MLR (69.8%, 80.1%, 67.2%, 63.2%). GBM models demonstrated the ten greatest predictors collectively explained 62.7-73.6% of variations in predicting HIV/STIs. STIs symptoms, past syphilis infection, age, time living in Australia, frequency of condom use with casual male sexual partners during receptive anal sex and the number of casual male sexual partners in the past 12 months were most commonly identified predictors.

CONCLUSIONS

Machine learning approaches are advantageous over multivariable logistic regression models in predicting HIV/STIs diagnosis.

Grindr Users Take More Risks, but Are More Open to Human Immunodeficiency Virus (HIV) Pre-exposure Prophylaxis: Could This Dating App Provide a Platform for HIV Prevention Outreach?

BACKGROUND

Technology has changed the way that men who have sex with men (MSM) seek sex. More than 60% of MSM in the United States use the internet and/or smartphone-based geospatial networking apps to find sex partners. We correlated use of the most popular app (Grindr) with sexual risk and prevention behavior among MSM.

METHODS

A nested cohort study was conducted between September 2018 and June 2019 among MSM receiving community-based human immunodeficiency virus (HIV) and sexually transmitted infection (STI) screening in central San Diego. During the testing encounter, participants were surveyed for demographics, substance use, risk behavior (previous 3 months), HIV pre-exposure prophylaxis (PrEP) use, and Grindr usage. Participants who tested negative for HIV and who were not on PrEP were offered immediate PrEP.

RESULTS

The study included 1256 MSM, 1090 of whom (86.8%) were not taking PrEP. Overall, 580 of 1256 (46%) participants indicated that they used Grindr in the previous 7 days. Grindr users reported significantly higher risk behavior (greater number of male partners and condomless sex) and were more likely to test positive for chlamydia or gonorrhea (8.6% vs 4.7% of nonusers; P = .005). Grindr users were also more likely to be on PrEP (18.7% vs 8.7% of nonusers; P < .001) and had fewer newly diagnosed HIV infections (9 vs 26 among nonusers; P = .014). Grindr users were also nearly twice as likely as nonusers to initiate PrEP (24.6% vs 14%; P < .001).

CONCLUSIONS

Given the higher risk behavior and greater acceptance of PrEP among MSM who used Grindr, Grindr may provide a useful platform to promote HIV and STI testing and increase PrEP uptake.

Acute and early HIV infection screening among men who have sex with men, a systematic review and meta-analysis

INTRODUCTION

Screening for acute and early HIV infections (AEHI) among men who have sex with men (MSM) remains uncommon in sub-Saharan Africa (SSA). Yet, undiagnosed AEHI among MSM and subsequent failure to link to care are important drivers of the HIV epidemic. We conducted a systematic review and meta-analysis of AEHI yield among MSM mobilized for AEHI testing; and assessed which risk factors and/or symptoms could increase AEHI yield in MSM.

METHODS

We systematically searched four databases from their inception through May 2020 for studies reporting strategies of mobilizing MSM for testing and their AEHI yield, or risk and/or symptom scores targeting AEHI screening. AEHI yield was defined as the proportion of AEHI cases among the total number of visits. Study estimates for AEHI yield were pooled using random effects models. Predictive ability of risk and/or symptom scores was expressed as the area under the receiver operator curve (AUC).

RESULTS

Twenty-two studies were identified and included a variety of mobilization strategies (eight studies) and risk and/or symptom scores (fourteen studies). The overall pooled AEHI yield was 6.3% (95% CI, 2.1 to 12.4; I2  = 94.9%; five studies); yield varied between studies using targeted strategies (11.1%; 95% CI, 5.9 to 17.6; I2  = 83.8%; three studies) versus universal testing (1.6%; 95% CI, 0.8 to 2.4; two studies). The AUC of risk and/or symptom scores ranged from 0.69 to 0.89 in development study samples, and from 0.51 to 0.88 in validation study samples. AUC was the highest for scores including symptoms, such as diarrhoea, fever and fatigue. Key risk score variables were age, number of sexual partners, condomless receptive anal intercourse, sexual intercourse with a person living with HIV, a sexually transmitted infection, and illicit drug use. No studies were identified that assessed AEHI yield among MSM in SSA and risk and/or symptom scores developed among MSM in SSA lacked validation.

CONCLUSIONS

Strategies mobilizing MSM for targeted AEHI testing resulted in substantially higher AEHI yields than universal AEHI testing. Targeted AEHI testing may be optimized using risk and/or symptom scores, especially if scores include symptoms. Studies assessing AEHI yield and validation of risk and/or symptom scores among MSM in SSA are urgently needed.

Increasing Condomless Anal Intercourse and HIV Prevalence Among Men Who Have Sex with Men Who Have Never Been Tested for HIV Before: A Serial Cross-Sectional Study in Shenyang, China from 2012 to 2016

Despite the high HIV incidence among men who have sex with men (MSM) in China, over half of MSM have never been tested for HIV before (MSMNT). Through a serial cross-sectional study from 2012 to 2016 in Shenyang, China, we studied 1036 MSMNT, and diagnosed 16.2% (168/1036) with HIV. The percentage of MSMNT who had condomless anal intercourse (CAI) in the past year increased from 42.1% (130/309) in 2012 to 63.4% (102/161) in 2016 (P < 0.001). 61.9% (104/168) of HIV-positive MSMNT had CAI and this percentage remained constant for the study period (P = 0.593). 53.3% (463/868) of HIV-negative MSMNT had CAI and this percentage significantly increased over the study period (P < 0.001). Encouraging HIV testing in this key subset through online HIV risk self-evaluation tools and HIV self-testing kits may help mitigate the overall MSM HIV incidence.

Measuring HIV Risk Perception and Behavior: Results from Round 1 of the Cognitive Interviewing Project with young women and men who have sex with men in South Africa

Self-reported HIV risk perception and behaviors are used in a variety of settings for diverse purposes, such as HIV prevention program planning and screening. Careful consideration of how youth in high HIV prevalence areas interpret these kinds of questions warrants attention. The Cognitive Interviewing Project (CIP) conducted cognitive interviews on common risk survey items with 30 cis-female and 20 MSM youth (18 to 24), who had recent sex with a male partner, in Cape Town and Vulindlela, South Africa. Results identified a number of potential issues including (1) confusing text; (2) mismatches of terms with local usage; (3) confusion with items requiring self-tailoring; (4) presentation concerns limiting selection of full range of answers; and (5) challenges reporting on information dependent on partner (eg., HIV risk, HIV status of partner). Self-report Items used to identify those at elevated risk for HIV should be evaluated with local populations to optimize shared understanding.

Different guidelines for pre-exposure prophylaxis (PrEP) eligibility estimate HIV risk differently: an incidence study in a cohort of HIV-negative men who have sex with men, Portugal, 2014-2018

IntroductionGuidelines for pre-exposure prophylaxis (PrEP) provide criteria to identify individuals at higher risk of HIV infection. We compared the ability to predict HIV seroconversion of four guidelines: the World Health Organization (WHO), the United States Public Health Service and Centers for Disease Control and Prevention (US CDC), the European AIDS Clinical Society (EACS) and the Portuguese National Health Service (PNHS).AimWe aimed to measure the association between guideline-specific eligibility and HIV seroconversion.MethodsWe studied 1,254 participants from the Lisbon Cohort of men who have sex with men with at least two evaluations between March 2014 and March 2018, corresponding to 1,724.54 person-years (PY) of follow-up. We calculated incidence rates (IR) according to each guideline eligibility definition and incident rate ratios (IRR) to test the association between eligibility at baseline and HIV seroconversion.ResultsWe found 28 incident cases (IR: 1.62/100 PY; 95% confidence interval (CI) 1.12-2.35). Guidelines' sensitivity varied from 60.7% (EACS) to 85.7% (PNHS) and specificity varied from 31.8% (US CDC) to 51.5% (EACS). IR was highest among those defined as eligible by the PNHS guideline (2.46/100 PY; IRR = 4.61; 95% CI: 1.60-13.27) and lowest for the WHO guideline (1.89/100 PY; IRR = 1.52; 95% CI: 0.69-3.35).ConclusionsBeing identified as eligible for PrEP was associated with a higher risk of infection. The magnitude of risk varied according to the guideline used. However, the number of HIV infections identified among ineligible participants highlights the potential for missing people who need PrEP.

Health Care-Seeking Behaviors and Perceptions of Provider-Initiated Discussion of Pre-exposure Prophylaxis Among PrEP-Naïve HIV-Negative Men Who Have Sex With Men in Atlanta, Georgia

BACKGROUND

Given high rates of HIV among men who have sex with men (MSM) in the United States, there is a need to more effectively leverage the health care system to bolster promotion of pre-exposure prophylaxis (PrEP) to at-risk MSM.

METHODS

Using data collected from a 2018 venue-based cross-sectional survey, we examined factors associated with health care-seeking behaviors, discussing PrEP with a provider, and barriers to PrEP uptake among MSM. Associations between outcomes and respondents' sociodemographic characteristics and sexual behaviors were assessed using log binomial regression.

RESULTS

Of 478 MSM, 247 (51%) were PrEP-naïve and HIV-negative. Although 85% of PrEP-naïve MSM reported visiting a health care provider in the past year, only 31% recalled having any provider discuss PrEP. The most frequently cited reasons for not taking PrEP were low perception of personal risk of acquiring HIV (37%) and not knowing enough about PrEP (35%). Those who saw a provider in the last year were less likely than those who did not to cite lack of knowledge as a barrier to use (prevalence rate, 0.66, 95% confidence interval, 0.45-0.96).

CONCLUSIONS

Despite the majority of PrEP-naïve MSM interfacing with the health care system, recollection of discussing PrEP with providers was limited. Increased efforts to equip providers with the tools to discuss PrEP and address pressing concerns with at-risk individuals may help improve PrEP uptake among priority populations.

Validation of the San Diego Early Test Score for Early Human Immunodeficiency Virus Infection Among Amsterdam Men Who Have Sex With Men

The San Diego Early Test score is a simple risk-assessment tool for acute, and early human immunodeficiency virus (HIV) infection. Validation in a prospective cohort of Amsterdam men who have sex with men showed fair prediction of HIV seroconversion (AUC, 0.701). This score can help prioritize and target HIV-prevention strategies.

Genetic Network Analysis to Assess the Risk of Human Immunodeficiency Virus Transmission Among Men Who Have Sex With Men Seeking Partners on the Internet

BACKGROUND

Online partner seeking (OPS) among men who have sex with men (MSM) is associated with increased risk behavior including frequency of unprotected anal intercourse, number of partners, and incidence of sexually transmitted infections (STIs). However, the impact on transmission of human immunodeficiency virus (HIV) is uncertain.

METHODS

MSM diagnosed with acute and early HIV infection were recruited from the Primary Infection Resource Consortium. HIV transmission events in the year following infection were inferred using estimated date of infection combined with genetic network analysis with linked sequences defined as ≤0.015 sequences/site difference in the HIV type 1 (HIV-1) pol coding region. Participants completed a detailed baseline questionnaire including reported methods of meeting sexual partners, including OPS, in the prior 3 months, and regression was performed with inferred transmission as the outcome.

RESULTS

From 147 MSM who completed the questionnaire, there were an associated 20 inferred HIV transmissions. No association with OPS was found (odds ratio, 0.64 [95% confidence interval, .24-1.69]; P = .37), though individuals who reported OPS were more likely to have reported a greater number of partners (P = .003) and prior STIs (P = .002). Geospatial analysis did not indicate that OPS was associated with increased geographical reach of the user (P = .68).

CONCLUSIONS

Individuals reporting OPS did not have increased odds of inferred HIV-1 transmission in the year following infection using genetic linkage analysis despite apparently increased risk behavior. OPS also did not increase the geographic distance between genetically clustered HIV infections, suggesting that individuals mainly use the internet to meet partners in their local region.

Patterns and clinical consequences of discontinuing HIV preexposure prophylaxis during primary care

Introduction

Discontinuations of HIV preexposure prophylaxis (PrEP) by at‐risk individuals could decrease the effectiveness of PrEP. Our objective was to characterize patterns of, reasons for, and clinical outcomes associated with PrEP discontinuations in primary care.

Methods

We conducted medical chart reviews for patients prescribed PrEP during 2011 to 2014 at a Boston community health centre specializing in healthcare for sexual and gender minorities. Patients were followed through 2015. We characterized patients’ sociodemographics, relationship status, behavioural health conditions, patterns of and reasons for PrEP discontinuations, and HIV seroconversions. Cox proportional hazards models were used to assess patient factors associated with PrEP discontinuations.

Results

Of the 663 patients prescribed PrEP, the median age was 33 years, 96% were men who have sex with men (MSM) and 73% were non‐Hispanic white; 40% were in committed relationships and 15% had HIV‐infected partners. Patients either used PrEP continuously (60%), had 1 or more discontinuations (36%), or did not initiate PrEP (4%). Discontinuations were most often due to a decrease in HIV risk perception (33%), non‐adherence to care plans (16%), or insurance barriers (12%). Of the 7 (1.1%) PrEP patients diagnosed with HIV, 1 was HIV‐infected at baseline, 2 seroconverted while using PrEP, and 4 seroconverted after discontinuations. In a multivariable model adjusted for race/ethnicity, relationship status, substance use disorders, and insurance status, those who were less than 30 years old (aHR 2.0, 95% CI 1.4 to 2.9 for ages 18 to 24, aHR 2.2, 95% CI 1.6 to 3.1 for ages 25 to 29, vs. ages 30 to 39 years), who identified as transgender women (aHR 2.0, 95% CI 1.2 to 3.4, vs. cisgender men), and who had mental health disorders (aHR 1.2, 95% CI 1.1 to 1.4 for each additional disorder) were more likely to have discontinuations.

Conclusions

Discontinuations of PrEP use among this American sample of predominately MSM were common, particularly among patients who were younger, identified as transgender women, or had behavioural health issues. As HIV seroconversions occurred after discontinuations of PrEP, strategies to prevent inappropriate discontinuations are needed.

A Simple Symptom Score for Acute Human Immunodeficiency Virus Infection in a San Diego Community-Based Screening Program

Background

Treatment of acute human immunodeficiency virus (HIV) infection (AHI) decreases transmission and preserves immune function, but AHI diagnosis remains resource intensive. Risk-based scores predictive for AHI have been described for high-risk groups; however, symptom-based scores could be more generalizable across populations.

Methods

Adults who tested either positive for AHI (antibody-negative, HIV nucleic acid test [NAT] positive) or HIV NAT negative with the community-based San Diego Early Test HIV screening program were retrospectively randomized 2:1 into a derivation and validation set. In the former, symptoms significant for AHI in a multivariate logistic regression model were assigned a score value (the odds ratio [OR] rounded to the nearest integer). The score was assessed in the validation set using receiver operating characteristics and areas under the curve (AUC). An optimal cutoff score was found using the Youden index.

Results

Of 998 participants (including 261 non-men who have sex with men [MSM]), 113 had AHI (including 4 non-MSM). Compared to HIV-negative cases, AHI cases reported more symptoms (median, 4 vs 0; P < .01). Fever, myalgia, and weight loss were significantly associated with AHI in the multivariate model and corresponded to 11, 8, and 4 score points, respectively. The summed score yielded an AUC of 0.85 (95% confidence interval [CI], .77-.93). A score of ≥11 was 72% sensitive and 96% specific (diagnostic OR, 70.27).

Conclusions

A 3-symptom score accurately predicted AHI in a community-based screening program and may inform allocation of resources in settings that do not routinely screen for AHI.

High Rates of Subsequent Asymptomatic Sexually Transmitted Infections and Risky Sexual Behavior in Patients Initially Presenting With Primary Human Immunodeficiency Virus-1 Infection

Background

Knowledge of the risk factors of individuals with an asymptomatic sexually transmitted infection (STI) is essential for implementation of targeted STI screening strategies.

Methods

Between June 2015 and January 2017, an STI screening was offered to all participants in the Zurich Primary human immunodeficiency virus (HIV)-1 Infection study. Patients were tested for gonorrhea, chlamydia, syphilis, and hepatitis C virus (HCV).

Results

Of 214 participants, 174 (81%) were screened at least once. Most patients were men who have sex with men (MSM) (87.4%). Presenting with a primary HIV infection was associated with higher odds for later risky sexual behavior, as compared with presenting in the chronic phase (odds ratio [OR], 5.58; 95% confidence interval [CI], 3.68-8.8). In total, 79 STIs were detected, reflecting a high period prevalence of 33.3% (58 of 174 patients). Sixty-six percent of patients (52 of 79) were asymptomatic. Most common STIs were chlamydia (50.6%; 40 of 79 patients), gonorrhea (25.3%; 20 of 79), and syphilis (19%; 15 of 79). In a multivariable model, engaging in insertive (OR, 6.48; 95% CI, 1.14-36.76) or both insertive and receptive (4.61; 1.01-20.96) anal intercourse, STI symptoms (3.4; 1.68-6.89), and condomless sex (2.06; 1.14-3.74) were positively correlated with a positive screening result. The hazard of an incident STI increased with the presence of STI symptoms (hazard ratio, 3.03; 95% CI, 1.17-7.84) and any recent drug use (2.63; 1-6.9).

Conclusions

A trimonthly STI screening including asymptomatic individuals should be considered in this population, particularly in MSM who report sexual risk behavior.

Clinical Trial Registration

NCT 00537966.

Reasons Why Young Men Who Have Sex with Men Report Not Using HIV Pre-Exposure Prophylaxis: Perceptions of Burden, Need, and Safety

Uptake of pre-exposure prophylaxis (PrEP) has dramatically increased but remains well below the estimated number of individuals who could benefit from PrEP in the United States, and uptake remains limited among young men who have sex with men (YMSM) and MSM of color. Reasons for not adopting PrEP as a prevention strategy among those at elevated risk for HIV is an important area of inquiry that could advise efforts to better position PrEP as an active part of prevention programs. As part of a mixed methods study investigating experiences with repeat HIV testing, we identified main themes emerging from in-depth interview data pertaining to reasons why YMSM report not using PrEP, among YMSM with frequent access to HIV testing services. Themes from 14 in-depth interviews with predominantly Latino MSM for not using PrEP included perceived burden of daily dosing, feeling that risk was not high enough to warrant PrEP, and beliefs that PrEP would have severe adverse events affecting the kidneys and bones. Less prominent but noteworthy themes included stigma as a PrEP user, social or provider influence on decisions not to use PrEP, and preference for current prevention strategy. No differences in PrEP discourse were noted across those at different levels of HIV risk. Results suggest that efforts are needed to engage communities and individuals around PrEP-related education, facilitate risk evaluation, and reduce PrEP stigma. New formulations and nondaily regimens may also be of particular interest to YMSM who may perceive daily PrEP regimens as highly burdensome.

Brief Report: The Amsterdam Symptom and Risk-Based Score Predicts for Acute HIV Infection in Men Who Have Sex With Men in San Diego

OBJECTIVE

Dijkstra et al recently described a risk- and symptom-based score moderately predictive for HIV seroconversion in the preceding 6-12 months in men who have sex with men (MSM) in Amsterdam. Our objective was to determine whether this "Amsterdam Score" could also predict for acute HIV infection (AHI) in MSM.

DESIGN AND SETTING

This study is a case-control analysis of a prospectively enrolled cohort of MSM who voluntarily presented for HIV testing in San Diego. The study sample was composed of MSM who screened HIV antibody-negative and then either tested positive with AHI [HIV nucleic acid test (NAT)-positive] or tested HIV NAT-negative.

METHODS

The Amsterdam Score was calculated for each participant in the study sample. Score performance was assessed using receiver operating characteristic curves and their area under the curve (AUC). An optimal cutoff was determined using the Youden index.

RESULTS

Seven hundred fifty-seven MSM (110 AHI and 647 HIV NAT-negative) were included in the analysis. AHI and HIV-negative cases were similar in age [median 32 years (interquartile range 26-42) vs 33 (27-45), respectively, P = 0.082]. The Amsterdam Score yielded a receiver operating characteristic curve with an AUC of 0.88 (95% confidence interval: 0.84 to 0.91). An optimal cutoff of ≥1.6 was 78.2% sensitive and 81.0% specific.

CONCLUSIONS

The risk- and symptom-based Amsterdam Score was highly predictive (AUC of 0.88) of AHI in MSM in San Diego. The Amsterdam Score could be used to target NAT utilization in resource-poor settings among MSM who test HIV antibody-negative, although the potential cost-savings must be balanced with the risk of missing AHI diagnoses.

Using HIV Risk Prediction Tools to Identify Candidates for Pre-Exposure Prophylaxis: Perspectives from Patients and Primary Care Providers

Clinical guidelines for HIV pre-exposure prophylaxis (PrEP) include risk prediction tools to identify appropriate candidates. We conducted a qualitative interview study to explore the potential acceptability, interpretation, and anticipated impact of such tools from the perspectives of men who have sex with men (MSM) and primary care providers (PCPs). Our purposive sample of English-speaking participants included: (1) MSM reporting HIV risk behaviors (n = 32; median age = 38 years; 53% non-Hispanic white; 22% high school degree or less education); (2) PCPs specializing in health care for MSM (n = 12); and (3) PCPs in general practice (n = 19). MSM participants questioned the ability of risk tools to predict HIV acquisition, and their perceptions of what might constitute a high HIV risk score varied widely. Many MSM participants believed that receiving a high score would prompt them to consider PrEP or other risk reduction strategies. Some believed that the data would be useful, particularly if discussed with their providers, whereas others anticipated feeling fear, anxiety, or mistrust. PCPs expressed more confidence in HIV risk prediction and imagined integrating tools with medical histories and their clinical judgment to assess risk. PCPs were most enthusiastic about adopting HIV risk prediction as a teaching tool to help patients visualize and reduce risk, their concerns about time constraints notwithstanding. In conclusion, our findings suggest that PCPs' views of HIV risk prediction tools are generally positive, whereas MSM participants' are more mixed. Given that both groups emphasized the value of contextualizing risk, shared decision making may be needed to implement HIV risk prediction tools effectively.

External validation of a prediction tool to estimate the risk of human immunodeficiency virus infection amongst men who have sex with men

A human immunodeficiency virus (HIV) risk assessment tool was previously developed for predicting HIV infection among men who have sex with men (MSM), but was not externally validated. We evaluated the tool's validity for predicting HIV infection in an independent cohort.The tool was assessed using data from a retrospective cohort study of HIV-negative adult MSM who were recruited in Beijing, China between January 2009 and December 2016.High-risk behaviors occurring within 6 months before the survey were evaluated. Area under curve (AUC) of the receiver operating character curve (ROC) was used to quantify discrimination performance; calibration curve and Hosmer-Lemeshow statistic were used for calibration performance valuation; and decision curve analysis (DCA) was used to evaluate clinical usage.One thousand four hundred forty two participants from the cohort were included in the analysis; 246 (17.1%) sero-converted during follow-up. External validation of the tool showed good calibration, the Hosmer-Lemeshow test showed no statistical difference between observed probability and tool-based predictive probability of HIV infection (X = 4.55, P = .80). The tool had modest discrimination ability (AUC = 0.63, 95% confidence interval [CI]: 0.61-0.66). The decision curve analysis indicated that implementing treatment measures based on the tool's predicative risk thresholds ranging from 10% to 30% might increase the net benefit of treatment when compared with treating all or no MSM.The HIV risk assessment tool can predict the actual risk of HIV infection well amongst MSM in China, but it has a moderate ability to discriminate those at high risk of HIV infection.

Development and Validation of a Personalized Social Media Platform-Based HIV Incidence Risk Assessment Tool for Men Who Have Sex With Men in China

BACKGROUND

Personalized risk assessments can help medical providers determine targeted populations for counseling and risk reduction interventions.

OBJECTIVE

The objective of this study was to develop a social media platform-based HIV risk prediction tool for men who have sex with men (MSM) in China based on an independent MSM cohort to help medical providers determine target populations for counseling and risk reduction treatments.

METHODS

A prospective cohort of MSM from Shenyang, China, followed from 2009 to 2016, was used to develop and validate the prediction model. The eligible MSM were randomly assigned to the training and validation dataset, and Cox proportional hazards regression modeling was conducted using predictors for HIV seroconversion selected by the training dataset. Discrimination and calibration were performed, and the related nomogram and social media platform-based HIV risk assessment tool were constructed.

RESULTS

The characteristics of the sample between the training dataset and the validation dataset were similar. The risk prediction model identified the following predictors for HIV seroconversion: the main venue used to find male sexual partners, had condomless receptive or insertive anal intercourse, and used rush poppers. The model was well calibrated. The bootstrap C-index was 0.75 (95% CI 0.65-0.85) in the training dataset, and 0.60 (95% CI 0.45-0.74) in the validation dataset. The calibration plots showed good agreement between predicted risk and the actual proportion of no HIV infection in both the training and validation datasets. Nomogram and WeChat-based HIV incidence risk assessment tools for MSM were developed.

CONCLUSIONS

This social media platform-based HIV infection risk prediction tool can be distributed easily, improve awareness of personal HIV infection risk, and stratify the MSM population based on HIV risk, thus informing targeted interventions for MSM at greatest risk for HIV infection.

Preexposure Prophylaxis for the Prevention of HIV Infection: US Preventive Services Task Force Recommendation Statement

IMPORTANCE

An estimated 1.1 million individuals in the United States are currently living with HIV, and more than 700 000 persons have died of AIDS since the first cases were reported in 1981. In 2017, there were 38 281 new diagnoses of HIV infection reported in the United States; 81% of these new diagnoses were among males and 19% were among females. Although treatable, HIV infection has no cure and has significant health consequences.

OBJECTIVE

To issue a new US Preventive Services Task Force (USPSTF) recommendation on preexposure prophylaxis (PrEP) for the prevention of HIV infection.

EVIDENCE REVIEW

The USPSTF reviewed the evidence on the benefits of PrEP for the prevention of HIV infection with oral tenofovir disoproxil fumarate monotherapy or combined tenofovir disoproxil fumarate and emtricitabine and whether the benefits vary by risk group, population subgroup, or regimen or dosing strategy; the diagnostic accuracy of risk assessment tools to identify persons at high risk of HIV acquisition; the rates of adherence to PrEP in primary care settings; the association between adherence and effectiveness of PrEP; and the harms of PrEP when used for HIV prevention.

FINDINGS

The USPSTF found convincing evidence that PrEP is of substantial benefit in decreasing the risk of HIV infection in persons at high risk of HIV acquisition. The USPSTF also found convincing evidence that adherence to PrEP is highly associated with its efficacy in preventing the acquisition of HIV infection; thus, adherence to PrEP is central to realizing its benefit. The USPSTF found adequate evidence that PrEP is associated with small harms, including kidney and gastrointestinal adverse effects. The USPSTF concludes with high certainty that the magnitude of benefit of PrEP with oral tenofovir disoproxil fumarate-based therapy to reduce the risk of acquisition of HIV infection in persons at high risk is substantial.

CONCLUSIONS AND RECOMMENDATION

The USPSTF recommends offering PrEP with effective antiretroviral therapy to persons at high risk of HIV acquisition. (A recommendation).