Qualitative Insights Into Adherence to HIV Pre-Exposure Prophylaxis (PrEP) Among Australian Gay and Bisexual Men

Abstract

The number of gay and bisexual men (GBM) taking HIV pre-exposure prophylaxis (PrEP) to prevent HIV has rapidly increased since 2010, but limited information about barriers and facilitators to adherence has been reported outside of formal trial settings. We conducted semistructured in-depth interviews with 24 Australian cis- and transgender GBM with a history of PrEP use to gather data on adherence to PrEP. The majority of participants were able to access PrEP at no cost through implementation studies. Three key domains were explored—how individuals took PrEP, factors that aided PrEP adherence, and barriers to PrEP use. All participants recognized the importance of regular dosing to ensure protection from HIV, with some participants taking the initiative to pre-empt possible adherence obstacles and plan around these. Multiple strategies were used to aid adherence, including using tools such as a phone alarm and support and tips from other PrEP users, friends, or clinicians. Barriers to PrEP adherence included stigma, concerns about side effects, and difficulties in accessing PrEP. Although most participants encountered at least one barrier to PrEP use, they were resourceful and utilized a variety of approaches to ensure good adherence to PrEP was maintained. These narratives highlight a commitment to finding ways to make PrEP work in the daily lives of this cohort of Australian GBM, demonstrated by their active investigation of different routines to determine the most suitable dosing strategy, and creation of contingency plans if they were unable to access PrEP in their usual or preferred manner.

Introduction

HIV pre-exposure prophylaxis (PrEP), an oral regimen based on tenofovir and emtricitabine, is a highly efficacious HIV prevention strategy when used daily.^1,2 There is also increasing evidence to show that it is effective when used solely around the time of potential sexual exposures (“on-demand” or “event-driven” PrEP).^3,4 However, it comes with the caveat that high levels of adherence must be maintained to ensure protection.² Since the first trials demonstrating the efficacy of daily PrEP were published in 2010, PrEP has been recommended by a growing number of national^5
–7 and scientific^8,9 bodies.

Among gay and bisexual men (GBM), one of several key populations affected by HIV, the first randomized controlled trial (RCT) reported highly variable levels of adherence, and thus, differing levels of protection from HIV.^10,11 However, more recent data from open-label studies have displayed higher levels of PrEP adherence among GBM.^12
–14 The difference in adherence between the initial RCTs and the later open-label trials is likely attributable to participants in the later studies both knowing that PrEP is effective, and that they are taking an active drug.^15,16 Nevertheless, the heterogeneity of adherence results observed to date in this population, combined with a variety of barriers—financial, structural, or social—that an individual may face¹⁷ and how GBM manage adherence to PrEP, warrants further attention.

Factors that have been reported to be associated with higher levels of adherence to PrEP in quantitative studies of GBM include older age^18
–20 and higher education levels.^19,21,22 Engaging in riskier sexual practices, such as having condomless sex with casual partners, has also been found to be associated with higher rates of adherence in some studies.^21
–23 Similarly, barriers to PrEP use by GBM have been identified quantitatively. These include high costs,^19,24,25 disruptions such as homelessness or drug binges^26
–28 and side effects and concerns about long-term toxicities.^23,29,30 Adherence to PrEP has regularly been observed to decline over time,^18,31 a phenomenon reported across a range of therapeutic and nontherapeutic interventions for a number of conditions.^32,33

Previous Australian research has shown that two-thirds of GBM express a preference for daily PrEP, with smaller numbers preferring event-driven or periodic dosing strategies,³⁴ which entails taking four pills around the time of risk events,⁴ or taking PrEP daily only during seasons of risk,³⁵ respectively.

To date, there has been considerable qualitative literature exploring potential users' willingness to use^36
–38 or acceptability^16,39
–41 of PrEP. These behaviors comprise the early stages of the Motivational PrEP Cascade,⁴² but do not necessarily ensure uptake, as other barriers still need to be overcome before gaining access to PrEP.^43,44 With substantial increases in the number of people taking PrEP in recent years—particularly in the United States,⁴⁵ and also in other high-income settings such as France⁴⁶ and Australia⁴⁷—additional quantitative data about factors associated with PrEP uptake and usage are becoming available. Despite this, there is a dearth of information on the underlying processes, barriers, and facilitators that shape adherence outside formal clinical trial contexts, and as such, qualitative research is needed to elucidate the reasons behind the observed adherence patterns.

The highly regulated nature of clinical trials means that reported or actual behaviors such as adherence may be very different to “real-world” practices. Generally, adherence in early RCTs was low, attributed, in part, to participants not knowing if they were receiving PrEP or placebo.^18,48 However, participation in trials may include additional benefits such as improved access to healthcare and resources, which cannot be easily separated from motivations for accessing PrEP.⁴⁹ To this end, the Sydney IN-depth PrEP study (SIN-PrEP) was undertaken to explore issues related to PrEP use, including the notion of safe sex, attitudes to PrEP, and management of adherence. We present qualitative data from interviews conducted with current and former PrEP users investigating factors that shaped their pill-taking experiences and explore the reasons these specific factors aided or diminished their adherence.

Methods

Study design and population

SIN-PrEP was a qualitative study that explored the impact of PrEP on safe sex cultures in Sydney, Australia. Participants were recruited from a number of sources, including advertisements on online social networking sites, and by contacting participants in PrEP implementation studies who had consented to be contacted for other research. People eligible to be interviewed included GBM taking PrEP, HIV-positive or HIV-negative GBM whose sex partners were taking PrEP, and Australian-based healthcare providers and sector professionals. This analysis will focus on a subset of the interviews—only those conducted with HIV-negative cis- or transgender GBM who reported current or previous PrEP use. For the purposes of this study, we assume PrEP was taken daily, as specified in the Australian PrEP guidelines,⁵ and thus, adherence was defined as reporting taking seven pills a week.

Interviews began in October 2015, and at this time, the availability of PrEP in Sydney was limited to participants in a 300-person demonstration project,⁵⁰ or to those who were able to personally import medication. The personal importation of PrEP—ordering pills online in 3-month shipments from overseas, is legal in Australia with a valid prescription from a doctor. In March 2016, a large implementation project was launched in New South Wales,⁴⁷ which provided broad-scale free access to PrEP, subject to risk-related eligibility criteria. Initially, all participants who volunteered to be interviewed were cis-gender and taking PrEP continuously. To increase the diversity of experiences in the sample, transgender men who identified as GBM and GBM enrolled in PrEP studies who reported PrEP cessation were purposively sampled from a database of PrEP implementation study participants who had consented to be contacted.

All SIN-PREP participants provided written informed consent before being interviewed. The study was approved by the UNSW Sydney Human Research Ethic Committee (approval no. HC15305) and the ACON Research Ethics Review Committee (RERC 2015/08).

Data collection

Interviews were conducted between October 2015 and March 2017. Brief demographic information was collected from each participant before the interview, and participants were asked to choose personal pseudonyms for use in reporting results. The interviews were semistructured, with discussions revolving around three key themes: mechanics of PrEP access, reasons for PrEP use, and sex and HIV. The full list of possible interview domains is found in Supplementary Appendix SA1 (Supplementary Data are available online at www.liebertpub.com/apc). Topics covered in each interview depended on how the discussion unfolded, and what was deemed relevant for the individuals and their personal situation. Interviews lasted approximately 1 h and were audio-recorded then transcribed verbatim. At the conclusion of the interview, participants were invited to consent to being contacted for a follow-up interview in 9–12 months.

Analysis

This analysis was restricted to first-round interviews conducted with HIV-negative cis- and transgender GBM, who were taking PrEP within the 6 months before interview (n = 24). Further, it focused on how participants adhered to PrEP, which was one part of the broader interview about the impact of PrEP on participants' lives.

S.J.V. listened to the full audio recording of each of the interviews to understand the broader discussion and context and how this could impact on PrEP use, before focusing on the adherence section of each interview through close reading of each transcript. Notes were made about each interview and added to throughout the analysis process.

Iterative coding⁵¹ was used in conjunction with thematic analysis.⁵² An initial coding framework was developed based on the three key interview domains, with new codes added as new concepts identified from the interviews during the coding process. Each transcript was read and coded by S.J.V. to identify key domains and relevant quotations. After the first batch of transcripts had been analyzed, S.J.V. and B.G.H. met to discuss the preliminary coding and narrow down the broader topics initially included in the framework to more specific themes. All data were manually coded using Microsoft Word.

Results

Participants

Overall, 24 HIV-negative GBM (including 2 transgender men) who had used PrEP within the past 6 months were interviewed and included in this analysis. This included four men who had ceased taking PrEP. To protect participant identities, cis- and trans-status was not identified in this article when individual quotes are used. The age range was 18–53 years (median: 38 years). Participants reported a range of ways they accessed PrEP and often switched between modes of access. These included demonstration projects (n = 2) and implementation studies (n = 22), personal importation/ordering pills online (n = 6), or by taking the antiretroviral drugs prescribed for HIV postexposure prophylaxis (PEP) on an ongoing basis (n = 2). A diverse range of lived experiences were also described, including being a homeless man with a history of mental illness, navigating the health system as a trans man, and a teenager living with his conservative family who were not aware of his PrEP use.

Almost all study participants reported that they had taken PrEP daily, as per the Australian PrEP guidelines⁵ and the protocol of the largest Australian PrEP demonstration study, EPIC-NSW.⁵⁰ Two participants reported having stopped PrEP temporarily when they became unwell, to rule out PrEP as a causative factor of their symptoms. A further two participants took PrEP for a short period before discontinuation—one due to unbearable dizziness and nausea, and the other who said that he had only intended to take PrEP while he was using steroids and was thus engaging in higher levels of risk behaviors. Finally, one participant reported event-driven PrEP use—his pill-taking was timed with visits to his HIV-positive partner living in another city, and combined with the side effects he experienced, he wanted to minimize his exposure to PrEP.

Three major domains were explored through our analysis, each with several subthemes. Frequency of themes is shown in Table 1. These were based on the three key interview areas that specifically concerned adherence to PrEP. The first domain examined how individuals took PrEP and includes reflections on the process of establishing a routine, identifying potential disruptions to adherence and creating contingency plans for interruptions to PrEP dosing. The second investigated factor that aided individuals in taking PrEP, including tools, personal support, guidance or tips, and changing patterns of risk behaviors. The final domain concerned barriers to PrEP use, comprising discussion of actual and potential side effects, restrictions of dosing requirements, stigma surrounding PrEP use, and accessibility issues.

Table 1.

Frequency of Discussion of Adherence Subthemes During Interviews About Pre-Exposure Prophylaxis Use with Australian Gay and Bisexual Men (n = 24)

Domain	How do people take/adhere to PrEP?			What helps people take PrEP?				What barriers are identified?
Participant pseudonym	Figuring out a routine	Identifying known challenges	Planning for disruptions	Tools	Personal support	Guidance/tips	Risk behaviors	Health related	Adherence issues	Disclosure/stigma	Other
Calvin	X			X	X				X	X
Christopher	X						X		X
Chukki	X	X								X
David	X	X	X	X			X	X	X
Gordon	X		X	X	X	X			X	X	X
Ian	X		X	X					X
Jack	X	X	X	X	X				X		X
James	X		X	X		X				X	X
Jason	X					X
Josh	X	X	X		X	X	X	X
Lance	X	X		X	X						X
Liam	X			X					X	X
Manacounda	X	X		X	X		X
Mannie	X		X				X
Marc	X		X	X	X
Mark	X			X		X
Mitch				X						X
Paul	X	X	X	X
Rob		X		X
Ryan	X		X	X
Scott	X	X	X	X		X				X
Steve	X			X		X		X
Sugarballs	X	X		X	X	X		X
Teddie	X	X	X	X	X	X	X		X

PrEP, pre-exposure prophylaxis; X, subtheme arose during the interview.

How individuals adhere to PrEP

Participants reported three distinct strategies that were fundamental in determining how PrEP was incorporated into their lives. Almost all participants spoke about the importance of establishing a routine to determine the best time for them to take their PrEP pill. About half of participants were aware of aspects of their personal situations that could present difficulties in taking PrEP as intended, and a similar proportion also discussed how they planned for and counteracted disruptions to their regular routines.

Establishing a routine

Establishing a routine to support pill-taking was a pivotal part of initiating PrEP for most individuals. Participants experimented with a range of different schedules, but their choice of dosing time was primarily determined by one of three overlapping criteria: Taking PrEP with a meal, choosing a time that would minimize side effects, or incorporating PrEP into a previously established routine or pill-taking schedule.

I have it with my breakfast 'cause I [also take] two fish oil capsules. So I just make sure that when I'm having those, I've got my little blue pill next to it … I'm a very routine-based kind of guy. (Chukki, 43)

Some individuals also had to re-evaluate their preferred routine after a period of PrEP use due to varying circumstances. This included changing the dosing time to limit the impact of side effects (e.g., switching from morning to night dosing if they suffered from nausea), or to accommodate varying work or travel schedules.

I started taking it at night at first 'cause I'd heard things about side effects … And then I kind of gradually just changed the time of day. Every day I took it a little earlier and so I started taking them at the mornings. (Mark, 24)

Identifying disruptions

Almost half of the participants interviewed personally identified difficulties in maintaining their chosen PrEP dosing schedule. Travel and side effects were mentioned by a number of participants as having the potential to disrupt pill-taking, although this was not the case for all participants experiencing these disruptions.

The only time where it's become difficult to manage adherence is when shifting time zones. (Jack, 39)

Other participants also recognized periods in which they had been more forgetful or less adherent to their usual pill-taking schedule, and some participants implemented additional routines to help them manage such periods. Some participants became aware of regular occurrences of missed pills and made changes to their pill-taking routine to maximize the possibility of taking PrEP at the same time every day, as prescribed.

Weekends I don't have the same process for having breakfast. I generally go out … in the first couple of months, the only dosages I missed were on the weekend. (Chukki, 43)

Many participants had not previously taken daily medication and thus establishing a routine was in itself a novel challenge that required special attention.

It's interestingly hard, isn't it? Like if you've never taken a pill once a day. (Sugarballs, 30)

Creating contingency plans

Half of the participants commented that they had made contingency plans for potential or actual disruptions to their PrEP regimen. A common example centered on making plans for pill-taking when traveling, including carrying spare pills in their hand luggage or incrementally adjusting the time they took their pill to maximize convenience and minimize disruptions to their usual schedule.

I certainly have no dramas with travelling with the medication. I usually throw the bottle in my bag and just put one or two pills in my hand baggage so I can take one in-flight and there's usually a backup one in case the suitcase decides to go walk around. (David, 40)

Some participants also commented on being aware of refilling prescriptions with sufficient time to allow for any delays. This was particularly important for the individuals ordering PrEP online, for whom delays due to shipping or customs regulations were not uncommon.

I'm a very organised person … I can buy them in three lots at a time … sometime during the second one you make sure you placed your reorder for the next one, and you kind of keep a rolling stash going. (Mannie, 35)

A number of participants reported carrying spare pills with them at all times, either as a backup if they had forgotten to take their pill one day, or if they did not return home at night and thus did not have access to their pills.

I always have a bag with me, with a couple of tablets … you never know, you might sleep around one night. (Paul, 43)

Finally, a few participants also mentioned they were aware of alternative (albeit emergency) sources of PrEP if they were temporarily unable to access their own pills, including from friends, sexual health clinics, and hospital emergency departments (as nonoccupational PEP), or through health promotion services at LGBTI events.

If I needed, I know either through friends I could borrow one … Or, if it was a couple of days, I know how accessible it is through hospitals and through GPs, and health clinics for emergency supplies. (Teddie, 32)

Factors that aid adherence to PrEP

The vast majority of participants reported the use of a tool or tools to assist them with adherence, including phone reminders and pill boxes. A smaller number of participants were also aided in their adherence by support or tips from clinicians, friends, or other external sources such as online communities and forums. Finally, one-quarter of participants referred to varying levels of risk behaviors impacting on their adherence to PrEP.

Tools

Using a phone reminder or alarm was the most common strategy used by participants to aid adherence. However, phone reminders became irritating for some participants, particularly if they had not yet determined the most convenient time to take their pill, as reminders at inopportune moments were not useful prompts for pill-taking.

I used to get a notification reminding me to take it every day. But, yeah, eventually that just got annoying. (James, 32)

There were mixed attitudes among participants toward using pill boxes. While those who used them found them an effective tool to aid adherence, others viewed them with disdain as they were seen as something reserved for old or sick people.

I see pill boxes and I immediately think of very, very, very old people. And I'm not prepared to think of myself like that. (Steve, 53)

Another strategy that some participants used to aid adherence was keeping their PrEP pills in a visible location, whether this was storing the bottle in plain sight or removing a pill from the bottle in advance so they were aware if they had actually taken their PrEP for the day.

I, basically, just put my pill bottle next to my toothbrush and hair products in the morning so that it jogs my memory to make sure I take it. (Ryan, 30)

Many participants commented on the importance of being mindful when taking PrEP, enabling them to think back and recall if they had taken their pill. This was enhanced by associating pill-taking with another activity, such as a meal or brushing their teeth. When this was not possible, some participants reported emptying out their PrEP bottles and counting the number of remaining pills, or marking dates on a calendar each day to keep track of their pill taking. Finally, some participants noted that packaging similar to the oral contraceptive pill, with days of the week or dates marked on the packet, rather than loose pills in a bottle, would help them to ensure they had taken their pill each day.

I won't remember if I've taken it or not … I also go into my calendar and I put an event down. It'll say ‘PrEP’ for that day … So then if a couple of days later, I'm like, “Did I take my pill a few days ago?” I can check. (Calvin, 19)

Personal support

The importance of having a good support network to help people remember to take their pills, find out information about PrEP, persevere through difficulties such as side effects or setbacks in accessing medication, and make changes to dosing schedules cannot be underestimated. Support came from a range of sources, including siblings, friends, and colleagues.

One of the girls at work … It's like, “Have I taken my tablet this morning?” And she'll remember … It's not just me involved in all of this. There's lots of people. (Lance, 34)

Other participants were grateful for people in their lives who were more directly involved with their PrEP use, such as their doctor or partner. This could be for the advice they provided, or just the extra-friendly reminder to take their pills every day.

I'm a little bit forgetful myself but my partner always remembers when I don't. So that helps. (Marc, 32)

I really, really like the doctor that's looking after me. He's been really excellent at asking lots of questions and making sure that I feel comfortable and have a good understanding. (Manacounda, 30)

As mentioned previously, support also came in the form of knowing alternate sources of PrEP, such as friends (HIV positive or negative) or sexual health clinics. This empowered participants and made them feel more confident that that could maintain adequate adherence even if they were to forget to take a pill or be unable to access pills temporarily.

Guidance/tips

Participants were grateful for the guidance and tips they received, particularly when initiating PrEP or if they were having difficulties maintaining adherence. This information came from a range of sources, including clinicians and friends using PrEP, and was usually well received by participants.

There were some conversations with my friends to find out who else was on it and what their side effects were. And then, through the same conversation, we talked about the rhythms that worked for them. (Teddie, 32)

For instance, one participant who was part of a PrEP group on social media posted a question about how to space his doses when traveling, and received helpful advice from other PrEP users who had been in similar situations previously.

There's a Facebook group that I'm part of, I think it's one of the biggest PrEP information groups. And I made a little post in there asking what people thought. (Mark, 24)

However, a few participants also noted a lack of support or guidance from doctors or other medical staff, particularly when applied to some of the more complex cases. One participant was attempting to take PrEP on an event-driven basis and sought additional information from clinicians, but felt that they did not adequately provide the advice he was seeking. Another participant felt dismissed when he reported to clinicians that he was struggling with side effects, which led to several periods of stopping and restarting PrEP.

The doctors were really like, “You have to get back on it! You have to get back on it!” and really trying to get me back on it again. I was, “Oh, I don't want to! Okay, I'll try it again.” So I tried it three times and by the third time I was like, “I can't, I'm sorry. Like the side effects are too much”… The only thing they said was like, “Are you eating it with food?” (Sugarballs, 30)

Risk practices

As part of broader discussions about sexual practices, one-quarter of participants remarked that their adherence was directly affected by their perception of their HIV risk in the context of current or recent behaviors. Judgment of a sexual encounter as “higher risk” led to participants being more careful with the timing of their doses or taking additional steps, such as setting a temporary phone reminder, to ensure they did not miss a dose.

I can honestly say I am more vigilant and certainly acutely more aware of self-discipline in taking them [PrEP pills] if I have had a recent sexual encounter, particularly if it is I guess what you would call a higher risk. (David, 40)

Some participants also discussed a more general fear or anxiety surrounding HIV that motivated them to remain adherent to PrEP. This was not tied to any particular risk event, but rather, they relied on PrEP as an additional layer of HIV prevention, giving them more confidence in their sex lives. Knowledge of the importance of maintaining good adherence to ensure high levels of protection from HIV, regardless of risk events, was also evident as a motivating factor for some participants.

I tend to catastrophise … if you know it only works and it's most effective when you take it every day without fail, that's a very good motivator to make sure you do take it every day. (Mannie, 35)

Adherence also varied among participants who did not see PrEP as a long-term HIV prevention strategy, but rather, as a safety net during periods of heightened risk. A few participants noted that they had started PrEP due to a specific period of risk, such as an overseas holiday, or during a cycle of steroid use, which may have been associated with increased libido and sexual activity. This led to additional difficulties with adherence due to disruptions to regular schedules, combined with the short-term nature of pill-taking in these contexts.

I think in that three months I reckon I probably forgot to take it at least seven times … I knew I was engaging in this risky, crazy behaviour … before I had steroids, I certainly would have been more concerned than after I went on it. (Christopher, 38)

Barriers to PrEP adherence

Almost three-quarters of participants reported at least one barrier to PrEP adherence. These were divided into four main categories: health-related, dosing requirements, disclosure/stigma, and accessibility. About one-third of participants reported barriers pertaining to dosing requirements or disclosure/stigma, with fewer participants noting barriers related to general health or accessibility of PrEP. Finally, some participants faced unique individual-level barriers, including being homeless or having to navigate the health system as a trans man.

Health-related barriers

Health-related barriers to PrEP use included side effects and concerns about long-term toxicities. As noted previously, some participants experienced side effects so severe they had to stop PrEP completely, while other participants were initially affected by side effects but were able to persevere with PrEP, aided by additional support or changes to their dosing schedule.

The fact that I actually couldn't sleep started to be disturbing. I said, “Okay. I just won't take it tonight,” 'cause I was doing the night dose … So I didn't take the pill that night and I slept … But then I started taking this pill in the morning and I've never had that kind of sleeplessness since. (Steve, 53)

Some participants did not consider the potential long-term ramifications of PrEP use, as their primary concern was preventing HIV in the present. Further, the additional benefits PrEP provided, such as reduced anxiety around sex and greater awareness of sexual health, outweighed any negatives. However, other participants were worried about renal or bone toxicity with long-term PrEP use and took steps to avoid overexposure to medication.

There have been occasions where I've questioned whether I've taken it and, if I can't retrace my activities … I'll wait'til the next morning, just because I don't want to put my kidneys under an excessive workload by having to process a double dose. (David, 40)

Dosing requirements

The most commonly reported adherence barrier was forgetting to take a pill every day. This was attributed to several factors, including being busy, alarms not working, or the effect of changing time zones while traveling.

So sometimes my phone doesn't remind me … and then I won't remember if I've taken it or not. (Calvin, 19)

However, some participants emphatically noted that they had not experienced any adherence-related barriers, and even travel or being busy did not affect their ability to take their medication as prescribed.

I've never really had any issues, being in a rush and forgetting them or anything like that. It's just sort of routine. (David, 40)

Between these two contrasting groups of participants was a third group who mentioned they had occasional difficulties adhering to PrEP, usually due to short-term disruptions to their regular schedules. If pill-taking was associated with another activity that was altered for a period, PrEP could be forgotten about.

It became problematic again, when I would go away [for work] … I would have to try and remember it. So a lot of the time I did forget …'cause it's just too busy. (Sugarballs, 30)

Disclosure/stigma

There was a diverse range of lived experiences related to issues with disclosure or stigma that impacted on participants' ability to adhere to PrEP. These arose from both internal and external sources and affected pill-taking in several ways.

Some participants had not disclosed their PrEP use to their partners or family members with whom they were living, as these people were not comfortable with the idea of PrEP or the suggestions of sexual activity it was associated with. This complicated dosing regimens as participants had to keep their PrEP hidden—whereas having pills visibly displayed was a technique used to aid adherence—and also consider other peoples' schedules when identifying the best time to take their pills.

My long-term partner doesn't know I'm taking it. So that's just something that needs to be managed … I've actually taken the pills out of the container that they come in 'cause it makes too much noise. (Chukki, 43)

Alternatively, some participants were not comfortable with others finding out about their PrEP use because they themselves had not completely come to terms with it, which may be attributed to internalized stigma or homophobia, as discussed below. This discomfort was heightened for participants who were in situations where their PrEP use may have been unintentionally disclosed to others, for instance, due to a lack of privacy. One participant was temporarily staying in community housing and another traveled frequently for work and occasionally shared a room with colleagues; both of these men were concerned someone may recognize PrEP as an HIV medication.

I live in a shared environment … So I was naturally apprehensive because it's a blue tablet and it's got the name written on the outside of the bottle. I was nervous that they may work out what it was. (Mitch, 42)

Further, there was some discussion about the value judgments that may be placed on PrEP users, which came from both the PrEP user themselves and others. These concerns were associated with the implication that participants were HIV positive or engaged in certain types of stigmatized behaviors. One participant recognized this internalized stigma and noted that he had grappled with the decision about having his PrEP pills visible in his house.

I had a little bit of discomfort 'cause you know, the bright blue Truvada pills everyone knows what they are and there was a bit in me that was just like, “Ooh, do I really wanna tell the world, anyone who goes into my bathroom?” which includes family members and people who come over for dinner … I guess it's just old-school, sexual shame stuff. I was sort of struck by having a moment of, “Ooh, I'm slightly uncomfortable with this.” I still left it out but it was kind of an interesting moment. (Liam, 37)

Despite these concerns, many participants also stated they were happy to discuss PrEP with others, particularly current or future sexual partners. This opportunity for education was viewed by participants as a way to increase knowledge, acceptance, and use of PrEP, with one potential flow-on effect of reducing HIV stigma among both HIV-positive and HIV-negative individuals.

I've actually spoken to some colleagues at work about it before and they had no idea that it was a thing. Some straight colleagues. And they were amazed … So yeah I have no worries about anybody finding it and if they did, I'd be happy to tell them. (James, 32)

Accessibility

A number of barriers regarding access to PrEP were also explored in the interviews. The mechanism through which participants obtained PrEP varied not only between individuals but also over time for some individuals, which brought with it a range of difficulties. This included participants initially accessing PrEP through online pharmacies before switching to free access through implementation studies or vice versa. Each method of access required different types of planning, for instance, ensuring orders were placed with sufficient time to allow for drug shipment from overseas, attending quarterly study follow-up visits, or being able to get to a pharmacy that stocked PrEP.

One participant who was accessing PrEP through personal importation had difficulties finding a doctor who would write him a prescription. He also experienced anxiety about ordering medication online, with concerns about both the cost and efficacy of the medication.

Obtaining the medication was a problem because getting the script in the first place was the issue … I was very anxious about … paying out a lot of money over the Internet … ‘cause it involved a company in India. (Gordon, 50)

Other participants noted that they were fortunate that their financial or personal situations allowed them to access PrEP. However, they expressed concerns that the cost of PrEP or complicated prescribing guidelines could be prohibitive to someone on a low income or who was physically or socially isolated from the gay community.

It's never really been a problem to access it in terms of having to go back every month and have it dispensed. For me that's a little different because I work across the road from the dispensary … But, if I wasn't in that situation, I imagine it might be a bit more difficult. (Jack, 39)

Discussion

The current study fills an important gap in the literature about how Australian GBM adhere to PrEP in real-world settings. As we move from demonstration studies and implementation projects to more widespread PrEP use, it is increasingly important to have detailed qualitative data about facilitators and barriers to adherence. In interviews with 24 Australian cis- and transgender GBM, three key domains regarding adherence to PrEP arose: (1) how individuals adhere to PrEP; (2) factors that aid adherence to PrEP; and (3) barriers to PrEP adherence.

A key starting point for many individuals initiating PrEP was determining a suitable dosing time and identifying a routine to ensure good adherence could be maintained. Incorporating pill-taking into pre-established routines such as meal times was a common strategy used by participants and is often recommended as an adherence tool across many health settings.^53,54 Perhaps surprisingly for a younger, well-resourced and connected population, participants in this study did not rely solely on phone reminders, but used a range of strategies to aid adherence, such as having their PrEP bottle visibly displayed.

The beneficial impact that good support networks can have in aiding medication adherence has been noted throughout the health literature.^55,56 For individuals with supportive partners, colleagues, or friends, this creates a collegial atmosphere of pill-taking and provides positive adherence reinforcement. This is especially important when examined through a cognitive psychology lens, which paints adherence as an active learning process in which beliefs and choices of the medication-user shapes their acceptability of the medication.⁵⁷ However, reports from PrEP users in the present study about fear of disclosure to partners, family, or friends highlight an additional barrier to adherence individuals may face. A new stigma, that PrEP is associated with nonconformity to safe-sex norms,⁵⁸ has led to a phenomenon described as “the PrEP closet.”⁵⁹ Although the need for covert pill-taking has seldom been described outside of the HIV field, stigma exists around other medical conditions that can be perceived as self-inflicted⁶⁰ or shameful,⁶¹ which may thus prevent or reduce medication adherence.

Contrary to a number of other health conditions where individuals may not understand the risks associated with medication nonadherence, or are dismissive of the likelihood of negative outcomes,^60,62,63 the PrEP users interviewed were acutely aware of the risk of HIV in their lives. Further, participants made an active choice to continue taking PrEP—rather than being forced to take a medication for a pre-existing condition. Combined with reports of better adherence around the time of higher risk behaviors, this suggests that, contrary to what is reported in the adherence literature for other chronic conditions,^55,63 PrEP users are highly motivated and aware of their HIV risk, and thus more likely to be adherent.

Consistently across the health literature, forgetting to take medication is the most commonly reported reason for nonintentional medication nonadherence.^33,64 Although forgetfulness was cited as the primary reason for not taking PrEP as recommended in the present study, few participants reported more than fleeting issues with adherence. The initiative and pragmatism displayed by participants in identifying and planning for potential disruptions showed their commitment to pill-taking, despite other barriers they may face. This was also evident in a recent hypothetical study of substance users at high risk of HIV who reported that although incorporating PrEP into their erratic routines seemed overly complicated, some participants would consider attempting a daily PrEP regimen for the added protection and benefits it could provide them, especially during periods of high risk.⁶⁵ This suggests that PrEP may have broader reaching benefits, including improved health literacy and knowledge, increased self-confidence, and better health-seeking behaviors, as hypothesized previously.^66,67

Side effects are another commonly reported reason for medication nonadherence.^33,61,64 More specifically to PrEP, the appearance of a “start-up syndrome” upon initiation, causing symptoms such as nausea, gastrointestinal disturbances, and headaches, has been associated with poorer adherence,²⁹ although this did not appear to be the case among our study participants. Participants' awareness of potential long-term complications associated with PrEP use, including renal toxicity²³ and bone mineral density loss,³⁰ shows broad knowledge of PrEP. Having a good understanding of one's prescribed medications has previously been shown to be associated with greater motivation to adhere to therapeutic interventions.^60,62,63,68

Several of the factors associated with adherence discussed in this study have been previously noted in studies of Australian HIV-positive GBM taking antiretrovirals for treatment of HIV. This includes facilitators such as greater social support⁶⁹ and having a friendly and competent healthcare provider,⁷⁰ and barriers including side effects and forgetting to take medication,⁷¹ concerns about stigma,⁷⁰ and unwanted disclosure of antiretroviral use.⁶⁹

The heterogeneity of this cohort is evident in the diverse experiences described, including being homeless and mentally ill, or navigating the healthcare system as a trans man. Although the majority of individuals interviewed were able to access PrEP for free for a period through implementation studies or demonstration projects, disparities in PrEP access resulted in some participants having to pay to personally import PrEP every 3 months. Each of these situations presented additional barriers to adherence that needed to be overcome, but in doing so highlighted the dedication of this cohort in ensuring ongoing access and good adherence to PrEP.

These findings come with some caveats. First, participants volunteered to take part in the interviews and, as such may have had positive or negative experiences they wanted to share. Despite this, participants interviewed for this study came from a wide variety of backgrounds and included vastly different lived experiences. These narratives highlight the diversity of PrEP users and the significance of the broader context of participants' lives in shaping their responses and behaviors. While most participants were of Anglo-Celtic or Mediterranean ancestry, we did not systematically collect data on education and ethnicity of participants, which is a study limitation.

The openness and willingness of participants to engage with researchers and share their stories highlights the importance of both PrEP and this research in generating a solid knowledge base about adherence to PrEP by Australian GBM. Further, this sample did not aim to be representative of all GBM, but rather to explore a range of PrEP-related experiences relevant to the Australian setting, such as personal importation, access through the implementation studies, and PrEP cessation. Thus, these findings may not be generalizable to other settings around the world, given the different modes of PrEP access and differences in geography, economy, and politics, which can all facilitate or hinder PrEP uptake and access. However, the roll-out of PrEP in New South Wales has taken place on a population-based level, and adoption has been rapid.⁴⁷ This has been achieved through working in close partnership with government health departments and community organizations, and mimics the scale up of PrEP in other jurisdictions.

This study presents detailed qualitative data on barriers and facilitators to PrEP adherence among Australian GBM. Participants portrayed PrEP in an overwhelmingly positive light, focusing on strategies that helped them maintain good adherence, despite other barriers they may have faced. There was an underlying sense of individuals taking ownership of their PrEP use, actively investigating different routines to determine the most suitable dosing strategy, and creating contingency plans if they were unable to access PrEP in their usual or preferred manner. Participants relied on various support networks and sought out information from a number of sources to ensure they had a good understanding of PrEP. Finally, while some participants reported side effects that led to the discontinuation of PrEP, or problems with disclosure that impacted on their ability to take PrEP as desired, the general consensus was that PrEP was broadly beneficial to their lives, and individuals would do all that they could to maintain high levels of adherence and take PrEP as required for the foreseeable future.

Footnotes

Acknowledgments

We thank all the interview participants without whom this work would not have been possible. Funding for the study was provided by UNSW Sydney and the AIDS Trust of Australia.

Author Disclosure Statement

No competing financial interests exist.

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