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. Author manuscript; available in PMC: 2018 Jan 1.
Published in final edited form as: J Acquir Immune Defic Syndr. 2017 Jan 1;74(1):15–20. doi: 10.1097/QAI.0000000000001164

PrEP Uptake, Adherence, and Discontinuation among California YMSM Using Geosocial Networking Applications

Ian Holloway 1, Ryan Dougherty 1, Jennifer Gildner 1, Sean C Beougher 1, Craig Pulsipher 2, Jorge A Montoya 3, Aaron Plant 3, Arleen Leibowitz 1
PMCID: PMC5140696  NIHMSID: NIHMS810277  PMID: 27552158

Abstract

We investigated PrEP uptake, adherence, and discontinuation among young app-using MSM in California (N=761). 9.7% of participants had ever used PrEP; 87% of those deemed good candidates for screening (indicated by a CDC risk index score ≥10) were not current or past users. PrEP use was associated with higher income (aOR:4.13; CI:1.87-9.12), receptive condomless anal sex(aOR:3.41; CI:1.71-6.78), HIV-positive sex partners (aOR:2.87; CI:1.53-5.38), popper use (aOR:3.47; CI:1.96-6.13), and recent STI diagnosis (aOR:2.90; CI:1.64-5.13). 41.5% of users wanted help remembering to take PrEP. The top reason for discontinuation was concern about long-term side effects (33.0%). YMSM app users are prime candidates for PrEP, despite low uptake. Apps may be useful tools for PrEP information dissemination, adherence monitoring, and support.

Keywords: PrEP, PrEP uptake, PrEP adherence, PrEP discontinuation, young men who have sex with men, geosocial networking applications

INTRODUCTION

Across the U.S., cities, counties, and states are developing plans for “Getting to Zero” new HIV infections.1,2 These plans rely on two strategies: (1) routinizing HIV testing in high risk communities, linking to care those who test positive, and suppressing viral load among those who are already HIV-positive; and (2) avoiding new infections using a variety of prevention approaches such as pre-exposure prophylaxis (PrEP). Unfortunately, while much is known about increasing and sustaining engagement in HIV care, less is known about uptake of, adherence to, and the factors that support or hinder long-term use of PrEP.3

In California, as elsewhere in the U.S., HIV incidence is increasing among young men who have sex with men (YMSM), especially YMSM of color4. Recent estimates attribute two-thirds of all new HIV infections to MSM,4,5 with nearly one-third of those infected aged 20-29.4 Studies suggest that YMSM who use geosocial networking apps (GSN apps) may be at increased risk for HIV6 due to their having higher numbers of sex partners,7 more frequent condomless anal sex (CAS),8-10 and greater incidence of sexually transmitted infections (STI)7,10,11 compared to those who do not use GSN apps.

While some research into willingness to engage in PrEP has focused on GSN app users,12 there are relatively few studies that measure PrEP uptake in this demographic, and research examining PrEP usage has been largely limited to participants in clinical settings.13-17 While PrEP uptake is increasing, overall estimates remain low, with previous studies finding fewer than 5% of sampled MSM having ever taken it.18-24 These estimates, however, are mostly based on findings from studies in eastern cities,23,25,26 leaving estimates on PrEP uptake among YMSM in California – the state with the largest number of new HIV infections each year27 – largely unknown.

While PrEP is recommended by the Centers for Disease Control and Prevention (CDC) for high-risk MSM,28 past studies document numerous barriers to uptake among YMSM, including cost, availability, and fears of risk compensation (i.e., increased risk behavior triggered by decreased perception of risk).29-31 Data from clinical trials suggest factors influencing PrEP use and adherence are not well identified32 and questions remain about how to motivate uptake of and sustain adherence to PrEP for HIV prevention.33 The present study sought to understand current rates and correlates of PrEP uptake as well as PrEP adherence and discontinuation among YMSM who use GSN apps.

METHODS

Participants and Procedures

This analysis used data from an online survey conducted from July 9 to August 20, 2015. Participants were recruited through several popular GSN apps using pop-up messaging and banner ads targeting users ages 18-29 in California. YMSM interested in the study completed an eligibility screener confirming they were HIV-negative, a California resident, and between18-29 years old; it also confirmed their sex at birth as male and that they had male sex partners within the past 5 years. Completing the survey took approximately 20 minutes. Participants were compensated with $20 electronic giftcards for their time. All study procedures were approved by the UCLA North Campus Institutional Review Board.

Measures

The survey queried demographic information, including race/ethnicity, age, gender identity, sexual orientation, sexual behavior, current employment, highest level of education, annual income, current insurance coverage, homelessness in the past 12 months, and U.S. citizenship. Questions regarding sexual risk behavior in the past 6 months included number of male sexual partners, number of instances of receptive condomlessanal sex (CAS) and insertive CAS with an HIV-positive partner, number of HIV-positive partners, and ever exchanging sex for money. Other risk factors measured were STI diagnoses in the past year, substance use in the last 6 months, last HIV/STI test, and perceived risk for and concern about contracting HIV.

Using six of these risk measures, we calculated the MSM risk index based on the CDC’s recommendations.34 This risk index considers age, number of male partners, HIV-positive partners, receptive CAS, insertive CAS with an HIV-positive partner and methamphetamine use as factors in calculating a risk score (which can range from 0 to 45). Those with scores ≥10 on this scale warrant evaluation for intensive HIV prevention services including PrEP. Participants were also asked if they had ever taken PrEP. Those who had taken PrEP were asked if they were current users and about their experience using PrEP; those who had stopped taking PrEP were asked why.

Data Analysis

Bivariatechi-square tests comparing demographics and risk behaviors of those who had ever versus those who had never taken PrEP were performed to determine variables of interest for multivariate modeling. In cases where sample size was too small, Fisher’s exact test was performed. We used the Benjamini and Hochberg procedure, which ranks p-values from most to least significant, to control for false discovery at the 0.05 significance level.35 Statistically significant variables at the bivariate level were included in a multivariate logistic regression model of PrEP uptake; stepwise regression was used to arrive at the final model.

RESULTS

We screened 3,868 survey respondents, of which 1,777 met our inclusion criterion. Our final sample of complete surveys included 761 California MSM aged 18-29 who were sexually active in the past 5 years and had never been diagnosed with HIV/AIDS. Less than ten percent of participants (9.7%) reported ever taking PrEP, with 71.6% of those who had ever taken PrEP being current users. Mean participant age was 23 years (SD=3.2) with a smaller percentage of younger participants (ages 18-24) having ever taken PrEP (48.6%) compared to older participants (ages 25-29)(63.2%, p<0.05). The sample was racially/ethnically diverse and there were no statistically significant differences in PrEP uptake by race/ethnicity. Most men identified as gay (81.9%); among PrEP users, nearly all were gay identified (97.3%). Among those who had ever taken PrEP, 55.4% reported annual salaries ≥$30,000 compared to those who had never taken PrEP (28.5%). A higher percentage of those who had ever taken PrEP were currently insured (86.5%) compared to those who had never used PrEP (74.1%; p<0.05).

In general, PrEP users engaged in higher levels of HIV risk behavior than non-PrEP users. A greater percentage of those who had ever used PrEP reported six or more sexual partners within the past 6 months (71.6%) compared to those who had never used PrEP (37.0%; p<0.001). Similarly, greater percentages of PrEP users reported recent receptive CAS (82.4%) and insertive CAS with an HIV-positive partner (43.2%) than those who had never taken PrEP (52.4% and 22.0%, respectively; p<0.001). Higher percentages of PrEP users reported using poppers(63.5% vs. 21.5%) and other illicit drugs in the last 6 months (41.9% vs. 16.9%; p<0.001 in both cases) as well as testing positive for an STI within the past year (55.4% vs. 19.5%; p<0.001) compared to those who had never taken PrEP. A full list of bivariate correlates of PrEP uptake is listed in Table 1.

Table 1.

Participant Characteristics among YMSM in California by PrEP Use (N=761)

Variable Total Ever Used PrEP Never Used PrEP χ2(p-value)*
N (%) N (%) N (%)
Total 761 (100.0) 74 (9.7) 687 (90.3)
Demographic Characteristics
Age 6.0 (0.02)
 18-24 470 (61.8) 36 (48.6) 434 (63.2)
 25-29 291 (38.2) 38 (51.4) 253 (36.8)
Race/Ethnicity 6.1 (0.11)
 White 165 (21.7) 23 (31.1) 142 (20.7)
 Black/African-American 193 (25.4) 19 (25.7) 174 (25.3)
 Hispanic/Latino 243 (31.9) 16 (21.6) 227 (33.0)
 Other/mixed 160 (21.0) 16 (21.6) 144 (21.0)
Gender Identity (0.29)
 Male 742 (97.5) 73 (98.6) 669 (97.4)
 Other 19 (2.5) 1 (1.4) 18 (2.6)
Sexual Orientation 13.5 (0.001)
 Gay 623 (81.9) 72 (97.3) 551 (80.2)
 Bisexual 120 (15.8) 1 (1.4) 119 (17.3)
 Other 18 (2.4) 1 (1.4) 17 (2.5)
Education 4.3 (0.12)
 Less than high school 45 (5.9) 1 (1.4) 44 (6.4)
 Completed high school 155 (20.4) 12 (16.2) 143 (20.8)
 Some college and above 556 (73.1) 60 (81.1) 496 (72.2)
Employment 4.4 (0.22)
 Employed full-time 311 (40.9) 38 (51.4) 273 (39.7)
 Employed part-time 170 (22.3) 13 (17.6) 157 (22.9)
 Full-time student 181 (23.8) 13 (17.6) 168 (24.5)
 Other 99 (13.0) 10 (13.5) 89 (13.0)
Income 19.5 (<0.001)
<$9,999 186 (24.4) 10 (13.5) 176 (25.6)
 $10,000-$29,999 275 (36.1) 21 (28.4) 254 (37.0)
>$30,000 237 (31.1) 41 (55.4) 196 (28.5)
Current insurance 573 (75.3) 64 (86.5) 509 (74.1) 5.5 (0.02)
Homeless in the last 12 months 54 (7.1) 7 (9.5) 47 (6.8) 0.7 (0.41)
U.S. citizen 684 (89.9) 68 (91.9) 616 (89.7) 0.1 (0.81)
Sexual Risk and Protective Factors
6 or more male sex partners in the last 6 months 307 (40.3) 53 (71.6) 254 (37.0)
Had receptive anal sex with a man without a condom in the last 6 months 421 (55.3) 61 (82.4) 360 (52.4) 24.4 (<0.001)
Had an HIV positive male partner in the last 6 months 99 (13.0) 26 (35.1) 73 (10.6) 35.5 (<0.001)
Had insertive anal sex without a condom with an HIV positive man in last 6 months 183 (24.0) 32 (43.2) 151 (22.0) 16.5 (<0.001)
Ever exchanged sex for money, drugs, or place to stay 90 (11.8) 11 (14.9) 79 (11.5) 0.7 (0.39)
Last HIV test 49.8 (<0.001)
<6 months ago 426 (56.0) 70 (94.6) 356 (51.8)
 6-12 months ago 144 (18.9) 2 (2.7) 142 (20.7)
>12 months ago 97 (12.7) 2 (2.7) 95 (13.8)
 I’ve never been tested 94 (12.4) 94 (13.7)
STI diagnosis in the past year 175 (23.0) 41 (55.4) 134 (19.5) 48.6 (<0.001)
Last STI test 46.0 (<0.001)
<6 months ago 397 (52.2) 66 (89.2) 331 (48.2)
 6-12 months ago 160 (21.0) 6 (8.1) 154 (22.4)
>12 months ago 112 (14.7) 2 (2.7) 110 (16.0)
 I’ve never been tested 92 (12.1) 92 (13.4)
How would you rate your risk of getting HIV 29.0 (<0.001)
 Low 315 (41.4) 18 (24.3) 297 (3.2)
 Moderate 318 (41.8) 30 (40.5) 288 (41.9)
 High 94 (12.4) 23 (31.1) 71 (10.3)
How concerned are you about becoming infected with HIV 3.9 (0.14)
 Not concerned 197 (25.9) 16 (21.6) 181 (26.3)
 Somewhat concerned 235 (30.9) 18 (24.3) 217 (31.6)
 Very concerned 329 (43.2) 40 (54.1) 289 (42.1)
HIV Risk Score based on CDC Screener 25.3 (<0.001)
 Low (<10) 237 (31.1) 4 (5.4) 233 (33.9)
 High (≥10) 524 (68.9) 70 (94.6) 454 (66.1)
Substance Use (Last 6 Months)
 Alcohol 589 (77.4) 60 (81.1) 529 (77.0) 0.6 (0.43)
 Marijuana/pot 334 (43.9) 35 (47.3) 299 (43.5) 0.4 (0.53)
 Poppers 195 (25.6) 47 (63.5) 148 (21.5) 61.7 (<0.001)
Illicit drug use (i.e., heroin, cocaine/crack, methamphetamine/crystal, GHB, ecstasy/MDMA/Molly, Ketamine/K) 147 (19.3) 31 (41.9) 116 (16.9) 26.8 (<0.001)
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*

Fisher’s exact test was performed where cell sizes were small

Multivariate Correlates of PrEP Uptake

After adjusting for other variables in the model, those making ≥$30,000 had greater odds of being PrEP users compared to those making <$10,000 per year (aOR:4.13, CI:1.87-9.12, p<0.001). Receptive CAS in the last 6 months was positively associated with PrEP use (aOR:3.41, CI:1.71-6.78, p<0.001). Those who reported sex with an HIV-positive partner in the last 6 months had greater odds of being PrEP users compared to those without an HIV-positive partner (aOR:2.87, CI:1.53-5.38, p=0.001). YMSM who used poppers in the last 6 months had greater odds of being a PrEP user compared to those who did not use poppers (aOR:3.47, CI:1.96-6.13, p<0.001). Finally, an STI diagnosis in the past year was associated with being a PrEP user (aOR:2.90, CI:1.64-5.13, p<0.001). Table 2 contains multivariate results.

Table 2.

Multivariate logistic regression analysis of PrEP uptake among YMSM in California (N=698)*

Odds ratio 95% CI P-value
Annual income
 < $10,000 Ref.
 $10,000-$29,000 1.35 0.59-3.12 0.478
 $30,000 or more 4.13 1.87-9.12 <.001
Receptive CAS in the last 6 months 3.41 1.71-6.78 <.001
HIV positive partner in the last 6 months 2.87 1.53-5.38 0.001
Substance use in the last 6 months: poppers 3.47 1.96-6.13 <.001
Any STI diagnosis in the past year 2.90 1.64-5.13 <.001
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*

63 individuals were excluded due to missing income

Reasons for PrEP Initiation and PrEP Adherence

For those who had ever taken PrEP (n=74), the top five reasons for initiating PrEP were: (1) wanting to worry less about getting HIV (71.6%), (2) having more than one sexual partner (66.2%), (3) not always using condoms (52.7%), (4) having sex with people whose HIV status the participant didn’t know (50.0%), and (5) disliking condoms (32.4%). Smaller percentages reported having PrEP recommended to them by a doctor or healthcare provider (29.7%), a friend (23.0%), or a sex partner (12.2%).

Among current PrEP users (n=53), 92.5% reported taking PrEP 6-7 days per week. However, 41.5% indicated that they wanted help remembering to take PrEP. The average amount participants spent on PrEP, including clinical ancillary costs, was $88 monthly. Half (50.9%) received financial assistance and a quarter (24.5%) indicated wanting additional help paying for PrEP.

Reasons for Discontinuing PrEP

Among those who discontinued PrEP (n=21), the top five reasons for discontinuing were: (1) being concerned about the consequences of long-term PrEP use (33.3%), (2) being unable to afford a prescription for PrEP (28.6%), (3) using other strategies to reduce HIV risk (23.8%), (4) forgetting to take PrEP everyday (23.8%), and (5) being unable to afford the required medical visits for PrEP (19.0%).

DISCUSSION

PrEP implementation is crucial to advancing the goals of the National HIV/AIDS Strategy36 and forthcoming California statewide plan for “Getting to Zero.”37 Our study provides insights into current rates and correlates of PrEP uptake and reasons for initiation and discontinuation of PrEP among YMSM who use GSN apps. Overall, PrEP uptake remains low (9.7%), which is consistent with other studies of YMSM.18,23 While uptake is increasing, much remains to be done to increase PrEP usage among this high priority population.38

In our multivariate analysis, higher income was significantly associated with PrEP usage. These results, coupled with those indicating discontinuation of PrEP related to cost, underscore the need for programs and policies that offset the cost of taking PrEP. Programs that seek to enroll YMSM in insurance, along with co-payment assistance programs,39 are two strategies to reduce barriers among low-income YMSM. Several states, including New York, Colorado and Washington have implemented publicly funded programs to pay for PrEP – a strategy which ultimately may be cost saving.40

The remaining correlates of PrEP uptake were related to individual risk behaviors, such as receptive CAS, sex with an HIV-positive partner, and popper use, which often accompanies high risk sexual behaviors.41 While these cross-sectional results do not necessarily represent risk compensation among PrEP users, they may indicate PrEP is reaching many YMSM who are good candidates, as both CAS and sex with HIV-positive partners are screening questions on the CDC’s tool to evaluate for intensive HIV prevention services.28 The CDC tool omits popper use as a screening question, although recommended in predicting HIV incidence among MSM.34

Although not statistically significant in multivariate modeling, a greater percentage of PrEP users perceived themselves at high risk for HIV compared to non-PrEP users. These results point to the need for targeted strategies for identifying YMSM candidates for PrEP based on their risk perception and behavioral risk profile. In our study, 87% of those deemed good candidates for PrEP screening (indicated by a score ≥10 on the CDC risk index) were not current or past PrEP users. While it is important to educate and encourage health providers to ask their patients about sexual risk and PrEP, using GSN apps to disseminate information regarding PrEP, including where to go for PrEP, is warranted.

Self-reported PrEP adherence was high in our sample (>90%) – efficacy studies with MSM show that PrEP can be up to 96% effective even when taken only four times weekly42 – and may overestimate actual adherence, especially in light of the fact that nearly one-quarter of former users stated that difficulty remembering to take PrEP was a reason they discontinued it. Technology-supported adherence methods that have been successful in increasing ARV adherence may also be leveraged to support PrEP adherence.43,44

This study is among the first to measure PrEP uptake among a sample of YMSM in California. Data point to the need for increasing PrEP uptake through targeted messaging to YMSM GNS app users engaged in high-risk sexual behaviors. Developing programs and policies that offset the cost for low-income YMSM is a high priority for increasing PrEP uptake. This sample is not representative of all YMSM who use GSN apps and all data relies onself-report. Further research using medical records to track PrEP uptake and/or more sophisticated measures of adherence is warranted. Despite limitations, this study points to the importance of increased outreach to YMSM using GSN apps for PrEP information dissemination and adherence monitoring and support.

Acknowledgments

Source of Funding

This research was supported by California HIV/AIDS Research Program (CHRP; grant RP15-LA-007); the Center for HIV Identification, Prevention, and Treatment (CHIPTS; NIMH grant MH58107); the UCLA Center for AIDS Research (CFAR; NIAID grant AI028697); and the National Center for Advancing Translational Sciences through UCLA (CSTI; grant UL1TR000124).

Footnotes

Conflicts of Interest

The authors of this manuscript have no conflicts of interest to report.

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