Introduction
The early detection of HIV infection is an important health priority both for early treatment as well as for HIV prevention [1-5]. Among cohorts of individuals at high risk of HIV, very early detection of HIV infection is also necessary to understand the impact of vaccines or new drug treatments on primary HIV infection [6,7]. However, achieving early detection of HIV infection is problematical; many at-risk persons have difficulty seeking [8-11] and completing [12] HIV testing and counseling.
Theoretically, the early detection of HIV infection could be achieved in high-risk cohorts through increasing the frequency of standard HIV blood testing, which typically requires a blood draw and two visits to the clinic for pre- and post-test counseling. However, this method would be costly for the clinic, and inconvenient for cohort participants. Offering in-clinic rapid testing for HIV, which is now promoted by the Centers for Disease Control and Prevention [13], could improve the cost and convenience of testing [14]. However, a potentially more convenient method could utilize home specimen collection kits together with telephone counseling. This method may further reduce barriers to HIV testing among individuals at high risk [15-18], thereby allowing more frequent HIV testing and thus earlier detection of HIV infection.
Although home specimen collection kits are now available over the counter to those who can afford them, many concerns exist regarding the feasibility, acceptability, and safety of home HIV specimen collection and telephone counseling [19,20]. Few data are available on the actual effectiveness and safety of home specimen collection and telephone counseling among populations at high risk of HIV. However, results from a post marketing study [21] of one commercially available kit were encouraging. Among 174 316 clients using dried blood spot (DBS) home specimen collection and telephone counseling, 95% of the specimens received at the commercial laboratory were adequate for testing, and 97% of users called to get their test results. In addition, 88% of 1569 HIV-positive clients reportedly accepted referrals from the telephone counselors or had follow-up care. Survey data revealed that 50% had never been tested before, and those that tested HIV positive were more likely to be men who have sex with men (MSM), injecting drug users (IDU), and non-white. No significant adverse events were reported among these clients. However, these data were from a self-selected group of clients who both chose to use home-specimen collection kits, and to make a second optional telephone call to provide follow-up information.
To obtain a better understanding of the acceptability of home specimen collection and telephone counseling among participants and counselors in a high-risk cohort [the HIV Network for Prevention Trials (HIVNET) Vaccine Preparedness Study (VPS) Cohort], investigators first conducted a qualitative study [22] which revealed counselor concerns about the willingness/ability of clients to follow through with bimonthly home specimen collection for HIV testing. It was hypothesized that home collection of oral fluids (OF) may be more feasible than home collection of DBS. Counselors were also concerned that telephone counseling would be less effective and more dangerous than face-to-face risk-reduction counseling and results disclosure. However, VPS participants did not share the counselors' concerns, and found the idea of bimonthly home specimen collection and telephone counseling to be acceptable and preferable to standard HIV blood testing. Therefore, a 6 month study was designed to assess the discrepancies in the acceptability of home specimen collection noted between counselors and their clients, and to evaluate the feasibility of DBS and OF bimonthly home specimen collection and telephone counseling.
Materials and methods
The VPS is a longitudinal cohort (n = 4892) study of HIV seroincidence and risk behavior including MSM, male and female IDU, and women at heterosexual risk (WAHR) as a result of multiple sex partners or HIV-positive sex partners. The VPS followed participants through semi-annual visits for a period of 18 months. Follow-up visits included pre-test and post-test counseling and other assessments associated with vaccine and non-vaccine prevention trial planning. Participants from four sites (Denver, Philadelphia, Providence, San Francisco) with month 12 follow-up visits scheduled between July and November 1996 were randomly selected (475 of 2048) for possible participation in the HIV Early Detection Study (HEDS) (Fig. 1). This sample was stratified by site and risk group to resemble the full VPS cohort with regard to age, sex, race/ethnicity, and risk behavior (Table 1). Exclusion criteria included an HIV-positive test result at the month 12 visit, the inability to speak and read English, and inability to provide informed consent.
Individuals randomly selected for possible participation were approached in order of appearance by study site personnel at their routine 12 month visit and asked if they would be willing to participate in a study in which they would be randomly assigned to three cycles of bimonthly home OF or DBS collection. Participants were offered up to a US$60 incentive for participation in the study. Ten dollars was given at enrollment, US$10 was given for each of the three required specimen collections, US$10 was given for completing the end-of-study questionnaire, and US$10 was paid for completing all required specimen and data collection. Recruitment at a particular study site ended once the enrollment target for that site was reached.
After giving informed consent, participants were trained to collect both OF (OraSure.. HIV-1 Oral Specimen Collection Device, Epitope, Inc., Beaverton, OR, USA) and DBS (ChemTrak, Sunnyvale, CA, USA) specimens. Training included viewing a video that demonstrated both collection techniques, as well as practicing both collection techniques in the presence of study staff until they were able to collect specimens of each type adequate for testing. After completion of training, an envelope was opened that contained the participant's random assignment to three cycles of bimonthly home OF or DBS collection. Participants chose between face-to-face or telephone counseling and results disclosure, and were told that they would be asked to come to the study site for additional testing and face-to-face counseling if a DBS/OF specimen was HIV positive or indeterminate. On-site or telephone pre-test counseling could be scheduled before each specimen collection date at the participant's request.
Participants were then encouraged to take three home specimen collection kits with them, but were offered the option of having the kits mailed to them every 2 months or picking up the kits at the study site. Participants were instructed to collect specimens 4, 12, and 20 weeks after HEDS enrollment. The kits included all the necessary collection materials, collection and mailing instructions, as well as three postage-prepaid shipping boxes pre-labeled with the address for the HIVNET Central Laboratory (CL). At the end of the visit participants received calendars marked with specimen collection and post-test counseling appointments.
In addition to routine training in client-centered risk-reduction counseling recommended by the Centers for Disease Control and Prevention, study counselors received phone 'crisis' intervention training and were provided with scripts and a checklist protocol to guide their telephone counseling. Each testing cycle, counselors telephoned participants to leave a reminder message for specimen collection and to offer pre-test risk-reduction counseling, or sent a reminder by mail to participants with no telephone. The content of the counseling, when accepted, included a review, assessment and revision of the client's personal risk-reduction plan.
If specimens were not received by the CL within 2 weeks after the specimen collection due date, staff telephoned participants to find out why the specimen had not been received. Participants who had not collected the specimen were asked to do so immediately. If specimens arrived within 4 weeks of the scheduled date, they were considered adherent. Participants telephoned the site to receive post-test risk-reduction counseling and test results at the pre-scheduled time. If participants did not telephone in for their test results on schedule, staff attempted to contact participants.
The CL evaluated the adequacy of all specimens upon receipt. OF specimens were adequate for testing if the pad was appropriately packaged in a vial of preservative fluid with 0.75 ml of specimen available after centrifugation. DBS specimens were adequate if two one inch circles on a filter paper card were completely and uniformly covered with blood, soaked through, and free of layering, moisture, and debris. If specimens were inadequate, participants were notified, retrained if necessary, and asked to submit another specimen.
DBS and OF specimens were tested for HIV antibody using the appropriate version of the Vironostika HIV-1 Microelisa System (Organon Teknika, Durham, NC, USA). Specimens with initially reactive enzyme immunoassays were repeated in duplicate, and, if repeatedly reactive, confirmed using the Immunetics miniblot system with the Epitope HIV-1 Western blot. DBS specimens were also tested for HIV DNA using the Amplicor HIV-1 assay (Roche Diagnostic Systems Somerville, NJ, USA) polymerase chain reaction (PCR).
Study outcomes included the willingness to be randomized to bimonthly home specimen collection of OF or DBS, adherence to the home specimen collection schedule, and adequacy of specimens for testing. All outcomes were tested on the basis of the initial randomization. Participants who initially agreed to collect specimens, but changed their mind after randomization, were still included in the analysis. Outcomes were first compared using chi square analysis [23]. A general estimating equation (GEE) repeated measures logistic model was used to take into account within-subject correlation [24,25], and to assess whether adherence varied by study arm (OF, DBS) or time. With an overall expected seroincidence of approximately 1.5 per hundred person-years, this study was not expected to yield substantial information about the impact of disclosing HIV-positive test results; and in fact no new HIV infections were noted among study subjects.
A questionnaire measuring the acceptability and impact of bimonthly home specimen collection and telephone counseling was administered at the end of the study to 235 (98%) of 241 participants. Counselors (19) were also interviewed after completion of the study to solicit their opinions pertaining to the provision of home specimen collection and telephone counseling.
Results
Among the 475 VPS participants randomly selected, 297 were contacted before completion of the targeted 241 enrollments. One potential participant was ineligible as a result of the receipt of an HIV-positive test result at the month 12 visit; another was unable to speak and read English. Nine were unable to provide informed consent because of incarceration or altered mental status. Of the 286 participants who were eligible and offered enrollment, 45 refused (16%). The highest refusal rate was among MSM in San Francisco (30 of 100, 30%), which was significantly higher than the refusal rate among MSM from Denver (seven of 77, 9%, P = 0.0007), or IDU and WAHR from Philadelphia (five of 85, 6%, P = 0.00003). The refusal rate among WAHR from Providence (three of 24, 12%) was not significantly different than the refusal rates at any of the other sites. The most common reasons given for refusing enrollment was that the study would take too much time (n = 19), and that DBS collection would be too difficult or too painful (n = 10). Six participants reported that they did not want to collect specimens at home, and five reported that frequent testing would make them anxious. Three participants who refused reported that they would enroll if they could be assigned to collect OF specimens.
Telephone counseling
Of the 241 subjets enrolled, 228 (95%) chose to receive HIV counseling and results by telephone, including six out of eight participants who did not have telephones but still chose to call for their counseling and test results. All but two participants with phones agreed that study coordinators could call to remind them to collect specimens, offer pre-test counseling, or discuss inadequate specimens.
Adherence to bimonthly specimen collection
For the majority of study participants, three cycles of bimonthly home specimen collection were expected over the course of the study. However, a total of six participants in the DBS group and one participant in the OF group were late for their month 12 visit and were required to complete only two cycles of home specimen collection before their pre-scheduled 18 month visit. Among the OF and DBS groups, a total of 359 and 357 specimens were expected, respectively, over the course of the study. On an individual basis, 110 (92%) of 120 participants in the OF arm and 101 (84%) of 121 participants in the DBS arm returned all expected specimens, and 5 and 7% missed only one specimen, respectively (data not shown). Although overall adherence to the bimonthly schedule was high for both OF (96%) and DBS (90%) arms, DBS adherence was significantly lower (P = 0.02 after GEE adjustment for inter-person correlation and cycle) (Table 2). Furthermore, adherence was lower among WAHR compared with MSM (P = 0.01). There was no significant difference in adherence between male or female IDU and MSM, nor was adherence significantly associated with race or age. Moreover, adherence did not decrease over time. To achieve this adherence, reminder calls for late specimens were necessary for only 12 (5%) of the 241 participants, with 11 of the 12 participants requiring only one reminder telephone call for the entire three cycles of specimen collection.
Despite the pre-study concern that frequent home specimen collection for HIV testing might result in more clients dropping out of the VPS cohort, follow-up rates at the 18 month visit were actually higher for the group enrolled in HEDS (98%), compared with those not randomly selected to participate in HEDS (90%, P = 0.00003).
The mean time from the collection due date to specimen collection was 2 days by participant self-report. The mean time from the collection due date to specimen receipt in the laboratory was 10 days. These parameters remained constant over time. The specimens were mailed via first class US Post Office mail using business-prepaid postage. Staff performed test mailings and found a 6-9 day shipping delay, consistent with participant's self-report of the collection date in comparison with the CL receipt date. This delay required that test result disclosure be scheduled 2 weeks after specimen collection.
The adequacy for testing of specimens collected at home was 99% for both OF (n = 344) and DBS (n = 321), and no participants were required to come in for additional training.
Acceptability of home specimen collection and telephone counseling
Participant findings
Acceptability was high for bimonthly home specimen collection of both OF and DBS (Table 3), as evidenced by the actual adherence rates noted above and by the willingness of almost all participants in both groups (98% OF, 93% DBS) to continue bimonthly home specimen collection in the future. When acceptability variables were analyzed by risk group there was a sufficient sample size to detect differences of 10-20% between groups. No significant differences were noted in the willingness to do future bimonthly home specimen collection between risk groups.
Most participants found the kits easy to use and relatively few found that specimen collection took too much time. However, WAHR (4%) were less likely to think that DBS collection took too much time compared with MSM (22%, P = 0.03). Approximately a third of each group either disliked the OF collection pad taste or perceived DBS collection to be uncomfortable, depending on the strategy assignment. MSM and WAHR (45%) were significantly more likely to find DBS collection uncomfortable than male and female IDU (16%, P = 0.000). Almost all participants in both groups found specimens easy to prepare for mailing, including even DBS, which required a 4 h drying period.
When participants were asked whether they would be willing to collect specimens by the method that they did not receive, only 86% of those randomly assigned to OF said that they would be willing to collect bimonthly DBS specimens in the future, whereas almost all (97%) of those randomly assigned to DBS collection indicated that they would be willing to collect bimonthly oral fluids in the future. At the end of the study, 86% reported being willing to continue bimonthly home specimen collection if kits were provided at no cost, even if no incentive were offered. However, male and female IDU (75%) were significantly less likely to participate without incentive than MSM and WAHR (91%, P = 0.001).
In this study, pretest risk-reduction counseling was offered by telephone or face-to-face with each HIV test cycle. However, among 241 participants, only 45 (19%) elected to receive pre-test telephone counseling at any time during the three collection cycles, and only nine (4%) participants elected to receive pre-test counseling with each of the three collection cycles. The telephone risk-reduction counseling was also quite brief, with 35 (78%) of the pre-test counseling phone calls 10 min or less. The average duration of pre-test telephone counseling was 8 min. In addition, when participants were asked how frequently they would like risk-reduction counseling when HIV tested every 2 months, 55% indicated that they would like counseling as infrequently as every 6-12 months. MSM (34%) were less likely than all other risk groups (61%, P = 0.000) to desire risk-reduction counseling every 2 months.
Participants noted some disadvantages of telephone counseling compared with face-to-face counseling (Table 3), despite the fact that most participants declined pre-test counseling and 95% of study participants chose to receive post-test counseling and test results by telephone. Many participants thought that telephone counseling and on-site counseling were equally private and that telephone counseling was more convenient (78%), They also felt that on-site counseling was more supportive (66%) and comfortable (54%). When comparing counseling preference differences between risk groups, MSM (32%) were less likely than male IDU (50%, P = 0.03) to find on-site counseling more private than telephone counseling. MSM were also less likely (4%) than male IDU (36%, P = 0.000) and WAHR (22%, P = 0.000) to find on-site counseling more convenient than telephone counseling. However, WAHR (22%) were more likely than MSM (7%, P = 0.02) to find telephone counseling more comfortable than on-site counseling. Furthermore, both kinds of counseling were perceived as helpful, but most participants would prefer to receive positive test results in-person at the study site. When one client at high risk was asked why he chose telephone results disclosure, when he would prefer to receive positive results in person, he stated that he would come in for additional face-to-face counseling if his results were positive.
Counselor findings
Staff concerns about the safety and effectiveness of telephone counseling persisted to the end of the study: 15 of 19 counselors (79%) reported that they did not have the opportunity to do sufficient risk-reduction counseling with the majority of clients during the bimonthly telephone counseling sessions. A representative comment was: ''Before, I thought it might be possible to have a strong rapport with clients during phone sessions. At best it turned out to be more of a brief check-in.''
The counselors concurred that face-to-face counseling is more conducive to establishing rapport (100%), better for forming a risk-reduction plan (100%), more comfortable for discussing sensitive topics (95%), and better for communicating test results (74%). If a participant's test results were positive, only 16% of counselors felt that they could successfully give the results and do effective counseling by phone without further training or experience; 53% felt that they would need additional training or experience, and 26% anticipated that they would never feel confident. Counselors expressed concern that participants who receive positive test results by telephone instead of face to face might engage in more destructive behavior (89%), or experience more psychological distress (90%). Despite these concerns, 74% reported that telephone counseling should be offered in future studies. However, 42% reported that telephone counseling should only be offered, as in this study, in between regular 6 month visits that include face-to-face counseling.
Impact of frequent home specimen collection HIV testing
Participant and counselor findings
Overall, 84% of participants reported no increase in anxiety about HIV, with male IDU more likely to report an increase in anxiety (28%) than MSM (14%, P = 0.03). However, 58% of counselors remained concerned that bimonthly testing would make participants worry more about HIV. Most counselors (53%) worried that having test kits at home might cause breaches of confidentiality. Nearly all participants (92%) reported that they were not bothered that someone might see the kits at home, although male IDU were more likely to report being bothered that someone might see the kits at home (18%) than MSM (5%, P = 0.005). The majority of counselors (63%) remained concerned that home specimen collection for HIV might lead to increased domestic violence, yet participants reported no episodes of domestic violence during the study as a result of home specimen collection.
Regarding the impact of this study on HIV risk behaviors, participants in HEDS felt that bimonthly home specimen collection for HIV testing had reduced (21%) or not altered (77%) their HIV risk behaviors. Significantly more WAHR (48%) than MSM or IDU (17%) said their behaviors became less risky (P = 0.000). At the month 18 visit, 6 months after HEDS enrollment, there was no significant difference in the prevalence of reported unprotected intercourse or needle/works sharing between HEDS study participants and VPS cohort members who were not selected to participate in HEDS (Table 1). However, at the end of the study, nine out of 19 counselors remained concerned that bimonthly testing might cause participants to take more HIV acquisition risks.
Projected use of commercial home test kits
Most HEDS participants (94%) agreed that early treatment of HIV results in prolonged health. Seventy-five per cent said that, if they were not in a study, they would be likely to use commercial home test kits to find out if they had become infected so that they could get early treatment. No differences were noted based on the risk group. The frequency of projected use was inversely dependent on cost (Fig. 2). At the current market price of US$35-50 per kit, only 19-27% would test themselves as frequently as every 6 months, with female IDU more likely never to test (63%) than MSM (34%, P = 0.01); at US$5, 89% would test themselves at least every 6 months and 50% every 1-2 months, with female IDU more likely to test every 1-2 months (74%) than MSM (47%, P = 0.03).
Acceptability of rapid tests for HIV
To compare home collection with on-site rapid testing, participants were asked how willing they would be to join a study in which rapid testing for HIV was offered instead of home testing. Most (77%) were more willing to join if rapid testing were offered, with no differences noted between the risk groups. The reasons cited for preferring rapid testing focused on the elimination of anxiety, stress, and worry associated with the 2 week waiting period for negative results (`it's not the test that causes anxiety but the wait', as stated by one participant). Other reasons included the convenience of a single interaction with negative results, the possibility of early treatment, and the benefit of having a counselor on hand in case of positive test results. Staff concurred with participants: 79% thought that rapid tests should be made available to participants at the study site. One staff member said, 'The most often heard complaint is the waiting period from blood draw to result - if this could be done in one visit, patients and staff would be grateful!' Those who did not think that rapid tests should be made available were concerned about the unnecessary anxiety that could be produced by a false positive screening test result. Some counselors also conjectured that the waiting period may positively influence behavior change.
Discussion
This study demonstrated that bimonthly home specimen collection of both OF and DBS, with telephone counseling, is both feasible and acceptable for bimonthly HIV testing among participants in a high-risk cohort enrolled in a longitudinal study. All risk groups were successful in submitting adequate bimonthly specimens, even when difficulties existed with substance use, chaotic lifestyles, the lack of education, and poverty. In addition, the vast majority of all risk groups found these methods highly acceptable, and were willing to continue bimonthly testing in the future.
This study also demonstrated that whereas participants prefer many attributes of face-to-face risk-reduction counseling, when testing more frequently than every 6 months, additional concurrent counseling is not desired. Likewise, although most participants stated that they would prefer to receive HIV-positive test results and post-test counseling in person, the vast majority chose telephone results disclosure for convenience, knowing that they could come into the site for additional counseling, if positive.
This study was, however, unable to evaluate the outcome of the home collection and telephone counseling process for newly diagnosed HIV-positive participants, or the acceptability, feasibility, and impact of home specimen collection and telephone counseling among individuals at risk outside of the context of a research study. These results do suggest, however, that it would be worthwhile to evaluate the acceptability and feasibility of home specimen collection among high-risk individuals in outreach settings, especially those who are unwilling to come to a testing site, and that test costs may have a significant impact on the frequency of use of home specimen collection kits for HIV testing. If used for outreach testing, it may be important to provide clients with an initial training to increase comfort and familiarity with home specimen collection kits, given that these data showed that participants with more experience with DBS collection were more likely to be willing to collect DBS specimens in the future. Home specimen collection and telephone counseling may also potentially improve the rates of partner testing. Kits could be given to HIV-positive clients for the testing of sex or needle-sharing partners who are unwilling to come to a testing site.
Conclusion
Within the context of HIV vaccine and early intervention trials, home specimen collection and telephone counseling may facilitate the earlier detection of HIV infection. DBS specimens tested using PCR [26] would allow the detection of very early infection before seroconversion, and could also be used in vaccine trials to help distinguish between a vaccine-induced response and true HIV infection. Home specimens might be routinely collected and banked for future 'look back' testing of specimens from newly infected vaccines to assess the effects of vaccines on viral load early in the course of an infection [27]. Home specimen collection and telephone counseling would also be a convenient method for the long-term follow-up of participants, especially for those who move away from the study site. In fact, based on the results of this study, home collection of DBS with the option of telephone and in-person counseling, have been incorporated into remote follow-up procedures in HIVNET protocols.
This study also demonstrated persistent staff concerns regarding the safety and effectiveness of telephone counseling, although self-reported data from participants in the study provided no data to support most of the counselors' concerns. Future studies would be needed to compare the effectiveness of telephone counseling and face-to-face counseling in reducing HIV risk behaviors. Larger studies will also be necessary to evaluate the actual risks of providing HIV-positive test results over the telephone. These should include evaluations of morbidity after the receipt of positive test results, as well as an assessment of the impact on partner notification and follow-up for early treatment referrals, which will be important to establish if commercial kits are to be used more widely in HIV prevention efforts.
Acknowledgements
The authors would like to thank the following HED study group members for helping to make this a successful study: Renee Holt, Dale Dondero, Ken Miller, Tom LaSalvia, Betsy Stone, Roseanne Scotti, Rebecca Widom, and Dale Lawrence. The authors would also like to thank Ann Kurth and Katherine Phillips for their helpful editorial comments, Maria Witthans for her administrative assistance and Tom Koepsell for his scholarly advice.
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