Acceptability and efficacy of interactive short message service intervention in improving HIV medication adherence in Chinese antiretroviral treatment-naïve individuals
Patient Preference and Adherence
Acceptability and efficacy of interactive short message service intervention in improving hiV medication adherence in chinese antiretroviral treatment-naïve individuals
Ye ruan 2
Xueling Xiao 1
Jia chen 1
Xianhong li 1
Ann Bartley Williams 0
honghong Wang 1
0 school of n ursing, Yale University , West haven, cT, UsA
1 Xiangya school of n ursing, central south University , changsha, hunan, People's republic of china
2 n ursing Department, s econd Xiangya hospital
8 1 0 2 - l u J - 2 1 n o 7 0 2 . 6 4 . 9 5 . 7 3 y b / m o c . s s e r p e .vdo l.yn w o w e /w su :/s la tp n th rso froedm rpeoF PowerdbyTCPDF(ww.tcpdf.org)
Aim: The aim of this study was to examine the acceptability and efficacy of interactive short
message service (SMS) in improving medication adherence in antiretroviral treatment
(ART)naïve individuals living with HIV/AIDS in Hengyang, Hunan, China.
Background: SMS via mobile phone has emerged as a potential tool for improving ART
adherence. However, most studies used SMS only as a medication reminder, with few studies
exploring the effect of comprehensive, interactive SMS.
Patients and methods: In a randomized controlled trial, 100 HIV-positive patients on ART
for ,3 months were randomized into control or intervention arm. Participants in the control group
received routine standard instruction for ART medication in the HIV clinics, while the intervention
group received 6 months of an SMS intervention in addition to the standard care. A total of 124
text messages within 6 modules were edited, preinstalled, and sent to participants according to
personalized schedules. Knowledge (of HIV and HIV medications), self-reported antiretroviral
adherence (Visual Analog Scale [VAS] and Community Programs for Clinical Research on AIDS
[CPCRA] Antiretroviral Medication Self-Report), and CD4 count were assessed at baseline and
immediate post-intervention. Intervention participants were interviewed after completion of the
study about their satisfaction with and acceptability of the SMS intervention.
Results: Baseline assessments were comparable between arms. Repeated-measures analysis
showed that both HIV-related and ART medication knowledge of the intervention group showed
better improvement over time than those of the control group after the intervention (P,0.0001).
For the adherence measures, compared with the control group, participants in the intervention
group had significantly higher VAS mean score (Z=2.735, P=0.006) and lower suboptimal
adherence rate (Z=2.208, P=0.027) at the end of the study. The intervention had no effect on CD4
cell count. Almost all (96%) intervention participants reported satisfaction or high satisfaction
with the SMS intervention, with 74% desiring to continue to receive the SMS intervention. The
preferred frequency of messages was 1–2 messages per week.
Conclusion: An interactive SMS intervention with comprehensive content shows promising
efficacy in promoting medication adherence in ART-naïve individuals. Future work might further
refine its ability to optimally tailor the intervention for individual preferences.
Keywords: HIV, short message service, antiretroviral treatment, adherence, China
Antiretroviral treatment (ART) was initiated in 1996 and has contributed greatly to
the reduction in morbidity and mortality among people living with HIV (PLWH).1
The annual number of people dying from AIDS-related
causes worldwide has dropped from 2.2 million in 2005 to
1.6 million in 2012, due to the well-developed and rapid
scale-up of ART programs. The availability of and access to
ART have turned the HIV infection from a fatal disease into
a chronic and manageable one. ART also plays an important
role in HIV prevention under the strategy of
treatment-as8201 prevention.2 However, medication adherence is one of the
l--Ju most important determinants for treatment effectiveness.
21 PLWH may need to maintain as much as 90% adherence to
on7 suppress the HIV replication.3 Nonadherence and incomplete
.260 adherence are of concern because suboptimal adherence to
.594 ART leads to failure of viral suppression, occurrence of
.73 resistant viral strains, advanced disease progress, and much
/yb higher health costs.4,5 Previous studies showed that the
non.com adherence rate to ART ranged from 20% to 40%.6–8
rsse China has Asia’s second-largest HIV epidemic with
ep an estimated 0.78 million of PLWH.9 According to China
.vdow l.yno Center for Disease Prevention and Control, the
accumula/ww sue tive reported cases of HIV/AIDS were 574,755 by the end
:/tsp lan of 2015.10 Although HIV prevalence in the general
populaftroedhm rrspeooF tiisoinncisrelaoswin, gtraranpsmidilsys.ioAn naamtioonngalmpernoghraavmingtosepxrowviidthe mfreene
ART was launched in 2003, under which 448,196 PLWH
are currently receiving ART, 50,124 (11.2%) on second-line
ART and the rest on first-line regimens.10 However, the HIV
epidemic continues to advance, with the number of AIDS
cases still rising. By the end of 2014, among the 501,000
survived PLWH, 205,000 progressed to AIDS,11 suggesting
a great need for ART interventions to improve the
management of HIV infection.
Mobile telephones have become a new tool in chronic
disease management, including HIV infection.12,13
Interventions associated with information technology may include
reminders for patients and the promotion of information
transmission.14 Short message service (SMS) is a frequently
used communication tool that has become a widespread
medium for the delivery of behavioral interventions.15 A
systematic review showed that the majority of published
text-message interventions were effective in improving
medication adherence to ART.16 SMS offers many advantages,
such as low cost, easy and wide coverage, and the potential
for individualized instant delivery. Surveys showed that
.80% of the PLWH studied believed that SMS aided them
in treatment adherence and indicated their willingness to
SMS-based interventions have been tested in many
countries, but only one study using real-time text-message
reminders to improve adherence to ART has been conducted
in China,19 which showed only the reminding function
of SMS. Past studies mainly used SMS as a reminder for
medication taking,19,20 and studies on more comprehensive
functionality of SMS are lacking. In addition, information
on the optimal content, frequency, and scheduling of SMS
messages is limited.
In this study, we aimed to investigate the acceptability
and efficacy of an SMS intervention via mobile phones in
improving ART adherence in PLWH in China. Our goal was
to create a more comprehensive support system based on our
prior work in China.
conceptual framework for the study
The conceptual model in this study was based on the
Starks et al’s21 3-step adherence model that was formulated
for the intervention program on medication adherence and
within the context of tight-knit families and to address the
environment of societal stigma (Figure 1). This model
consisted of 3 steps to medication adherence, which is defined
as the actual ingestion of the correct dose of ART at the
appropriate time. First, patients ask for correct instructions
to take their medications (a cognitive component). Second,
patients have to be motivated to take the medications (a
psychological component). Third, patients need to have
the medication available and remember to take the
medication at the appropriate time, by either an internal cue (they
remember) or an external cue such as a prompt from a family
member or an alarm (social/mechanical component). The
current study addressed these 3 components via interactive
and comprehensive SMS intervention.
Patients and methods
Design, participants, and setting
We conducted a randomized controlled trial between March
2013 and March 2014, recruiting patients from an HIV clinic
in Hengyang city, a major HIV clinic in Hunan Province,
China. This clinic currently manages 3,900 patients, of
whom 2,800 are on ART. Eligible individuals 1) were at least
18 years old; 2) had confirmed an HIV diagnosis; 3) were
on ART for no more than 3 months; 4) were able to speak,
understand, and read Mandarin; and 5) had their own mobile
phone or regular access to a mobile phone. The study was
approved by the institutional review board Committee of
Xiangya School of Nursing, Central South University.
Participants who provided written informed consent were
randomized into a control or intervention group. Patients in
the control group received regular health education in the
clinic, including informational pamphlets, psychological
support, and personalized health education from nurses and
physicians in the HIV clinic. Participants in the intervention
group received the same usual care as the control group plus
SMS for 6 months. Data were collected at the baseline
(pretest) and at the end of the 6-month study (posttest).
The SMS intervention was designed and planned in
consultation with investigators, clinic staff, and patients and
families regarding the content, frequency, and scheduling
of the text messages. In total, 6 message modules and
124 text messages were edited and preinstalled, including
introduction and holiday and weekend greetings (14
messages), medication reminders and skills for good adherence
(47 messages), HIV/AIDS-related and medication knowledge
(49 messages), humor jokes (14 messages), and motivation
and encouragement (14 messages). The SMS intervention
aimed to increase knowledge, enhance medication adherence,
provide emotional support, and solve problems. All messages
were ,70 Chinese characters and did not specify HIV or
AIDS to maintain the confidentiality of receivers’ HIV status
(“virus” and “chronic illness” were used instead).
Scheduling of messages was determined by the
interventionists and participants at the baseline visit. For the first
3 months of the intervention, 5 preinstalled text messages
were sent to the participants every week, namely every
Monday, Wednesday, Friday, and weekends, while for the
last 3 months of the intervention, 3 text messages were
sent to the participants every week, namely every Monday,
Wednesday, and Saturday. Medication reminders were sent
to the participants about half an hour before their medication
time, while other messages were sent at 8 pm.
We adopted an interactive approach, with all text
messages sent through the working phones of interventionists
rather than the SMS platform, allowing the participants to
reply to the text messages when needed. The interventionists
chose multiple recipients (bulk messages) to improve the
efficiency. The participants were instructed that they could text
back any questions or comments to the interventionists.
We collected “demographic information” (ie, age, gender,
education level, housing condition, family yearly income,
and marital status) as well as “disease-specific data” (ie,
time since HIV diagnosis, time on ART, infection routes,
and ART regimen).
We assessed “HIV-related knowledge” with a
questionnaire originally developed in Mandarin and used in Chinese
workers.22 Its 10 items query the nature of the disease,
transmission routes, prevention measures, etc. Responses
to the questions were “yes”, “no”, and “not clear”, with
correct answers scoring 2 points and wrong answers scoring 0
to generate a total score from 0 to 20. “ART medication
knowledge” was assessed with a 13-item measure originally
developed and tested in China by Li23 and included items on
ART functions, methods and requirements of medication
taking, and management of side effects. The answers to
each item were right, wrong, and not clear. Correct answers
scored 1 point and other answers scored 0, with a total score
range of 0 to 13.
“ART adherence” was measured using 2 approaches.
The Community Programs for Clinical Research on AIDS
(CPCRA) Adherence Self-Report Questionnaire was used to
determine the percentage of doses taken in the 7 days before
the interview for each ARV prescribed. Participants were
asked to select 1 of 5 possible responses according to the
original measure: 100%, 80%, 50%, 30%, and 0%. A Visual
Analog Scale (VAS) was also used to measure the medication
adherence, with which participants reported their adherence
over the past 30 days on a 100-point scale (with no increments
indicated): 0 for taking no medication and 100 for taking all
of the prescribed medications. We measured the distance of
the tick mark they used to indicate adherence and created
a percentile score (a ratio-level variable). Responses were
dichotomized for the VAS, with the threshold for optimal
adherence set at 90% and above.24–26 Both measurements of
ARV adherence have been used successfully by the authors
in similar populations.27
The acceptability of the SMS intervention was assessed
in semi-structured individual interviews with participants at
the conclusion of the study. We assessed preferred message
types, preferred time and frequency of receiving messages,
and quality of messages. With 1 item, participants rated their
satisfaction toward the message intervention as 1 (highly
unsatisfied) to 4 (highly satisfied). In addition, all
textmessage communication between the interventionists and
the participants was recorded in the study log. In addition,
participants’ responses to messages were also recorded to
calculate the response rate.
0218 Data analysis
l--Ju Independent-sample t-tests, χ2-tests, and Mann–Whitney U
12 tests were used to compare the 2 study groups at the baseline.
on7 We used repeated-measures analysis of variance to compare
.602 the total score of medication knowledge in the 2 groups.
.945 Mann–Whitney U tests were used to compare the ART
adher.73 ence. Independent-sample t-tests were used to compare the
/yb differences in CD4 cell counts between the 2 groups. The
.com significance level used in the study was 0.05.
.vdo l.yn Participant characteristics
/w su From July 2013 to September 2013, 283 PLWH who came to
:/tsp lan the HIV clinic for medical service were screened: 180 PLWH
did not meet the criteria and 33 participants declined
participation (Figure 2). Totally, 100 PLWH completed the
baseline questionnaire: 50 in the intervention group and 50 in
the control group. During the 6-month follow-up, 2
participants died and 1 withdrew from the study in the intervention
group, while 1 died and 2 lost to follow-up in the control
group, with 94 participants completing the study.
As shown in Table 1, there were no significant
differences in any demographic or disease-related variable
between groups at the baseline. Overall, participants were
aged 40.3 years; 41% female and 54% reporting heterosexual
Compared with the control group, the mean scores for both
HIV-related and ART medication knowledge of the SMS
intervention group demonstrated a better improvement over
time than those of the control group after the intervention
(P,0.0001). The effect size of SMS intervention over time
for HIV-related knowledge and medication knowledge was
0.35 and 0.48, respectively (Table 2).
The participants reported VAS score of 98.72% in the
SMS group at the end of the study, significantly higher than
that in the control group (93.11%; P=0.006). Similar effect
on CPCRA adherence was noticed. With no difference at the
baseline, the percentage of people with suboptimal adherence
in the control group (27%) was significantly higher than that
in the intervention group (10.7%) in the posttest (P=0.027;
CD4 cell counts of this sample showed a normal
distribution according to the Kolmogorov–Smirnov tests. t-Test was
used to analyze the treatment outcomes, and no statistical
differences were found in either pretests or posttests between
the 2 groups (P=0.623; Table 4).
Use and acceptability of sMs
The majority of the participants replied to the SMS, although
response to each text message is not required. One patient
never replied, with a response rate of 97.87% in total. Over
half of the participants responded to 30%–50% of the
messages. In average, almost every participant contacted the
interventionist and replied 37 times. The topics of replying
messages included asking whether they could stop
medication if the CD4 cell count rose; how long they could live with
AIDS; whether HIV could be transmitted through coughing,
sneezing, or mosquito bites; how to deal with delayed
medications; expressing appreciation for encouragement; and a
good mood after receiving a humor or a joke.
Most participants (96%) in the intervention arm reported
satisfaction or high satisfaction with the SMS intervention.
Two participants (4%) were dissatisfied because they
disliked the frequency of messages: one complained that the
message bothered him too often, and the other said that he
hoped to receive messages every day. Unexpectedly, 35
participants (74%) responded that they would like to
continue to receive the SMS, indicating a good acceptability
of the SMS.
Participants generally preferred disease and
therapyrelated knowledge topics, followed by greetings and jokes,
emotional support, and reminders. The majority of
participants preferred to receive 1–2 messages each week, followed
by 3–5 messages per week (Table 5).
This study shows that SMS intervention can improve HIV/
AIDS-related knowledge and ART adherence. People who
potential benefit in improving or keeping ART adherence in
different areas.14 First, SMS could be used as a medication
reminder to improve ART adherence confirmed by previous
studies.12,19,20 Second, SMS intervention could improve the
level of HIV-related knowledge and ART knowledge in
ARTnaïve individuals, which is associated with optimal
medication adherence. Third, the interactive text message offered the
ART-naïve individuals a conduit for timely communication
with health care providers as to informational, emotional, and
technical supports to overcome the multitude of barriers they
faced at the start of ART. Miller et al29 claimed that SMS was
used not only to remind or send information to PLWH but
also, as a consistent and convenient way, to access emotional
support from health care providers.
As to the frequency of message sending, the participants
preferred 1–2 messages each week, followed by 3–5 messages
each week. Since our participants were ART-naïve, we sent
5 messages in the first 3 months (2 pieces of knowledge and
3 reminder messages per week). Although our findings did not
show what frequency had better effect, from our experiences
and feedback from the participants we found daily message
was not preferable. One of our participants complained of
too much messages. Pop-Eleches et al’s study12 showed
that weekly messages were more effective in improving the
adherence than daily reminders. A survey also showed that
participants favored the weekly message, no more and no
less.30 Daily messages might be considered intrusive, might
lead to habituation, and possibly decrease the responses to
repeated stimuli. We also assessed the participants’ favorite
message types. The participants preferred SMS regarding the
intervention not only as a reminder but also as a useful source
of information on HIV infection and medication management.
Similar findings were shown in Georgette et al’s study,30 in
which the participants reported a desire to have more varieties
in the message contents and most of them would like to read
more information about HIV medication in the messages.
Feedback from the participants of this study also
demonstrated a good acceptability to interactive SMS. Most
participants in the intervention group reported the help of
text messages in taking their medication, satisfaction with
the SMS education, and willingness to continue to receive
SMS messages in the future. They used the interactive SMS
as a tool for seeking information and consultation from health
care providers. SMS intervention offers the participants a
simple way to contact health care providers.17 It requires
basic text-messaging skills and low cost to participate. A high
response rate from this sample also showed the good
involvement of the participants. This study, along with previous
evidences,14,31 suggests that simple SMS intervention may be
an important strategy to sustaining optimal ART responses,
especially in the resource-limited settings.
We failed to find that the SMS had a significant impact
on the increase in CD4 cell counts in the 6-month follow-up,
which was not consistent with previous studies stating that
SMS could improve ART adherence and the biological
outcomes of ART, including suppressed viral load and increased
CD4 cell counts.14,32 Mannheimer et al33 also claimed that the
higher the ART adherence, the faster the CD4 cell growth.
This study did not last long enough for us to observe the
change in CD4 cell counts. In addition, Townsend et al34
showed that when ART adherence was .70%, with no
correlation between the ART adherence and the increase in
CD4 cell counts, it might partially explain the significant
difference in CD4 cell count increase. We used CD4 cell
count only as the biological outcome because patients could
access only the test of CD4 cell counts every 6 months since
viral load test was not routinely accessible. This limits the
sensitivity for evaluating the biological outcome of SMS
intervention, because viral load test is a more sensitive
indicator for ART effectiveness.
Confidentiality is a great concern for SMS participants.
Designing ethically appropriate text messages should be
the focus to avoid unwanted disclosure of HIV status and
protect the participants’ privacy. In our study, more than
half of the participants were concerned about words such as
AIDS or HIV that might appear in the text messages; some
participants preferred to use “ABC” or “123” to replace or
code these terms. Due to the customary use of mobile phones
by more than 1 individual in some settings, cell phone
messages need to continue to consider confidentiality issues.
SMS involves risks and should not include any HIV-related
terms in the messages.35
There are several limitations in this study. The relatively
small sample size might weaken the power of the study.
Participants of the 2 arms were recruited from the same HIV
clinic and might share information, which might result in
contamination. Furthermore, 6-month follow-up is not long
enough to determine the effect of SMS intervention. A longer
follow-up is preferred.
Interactive SMS intervention has a promised acceptability
in ART-naïve individuals in China. It demonstrates the
preliminary efficacy in improving HIV-related and
medication knowledge and adherence to ART in PLWH. However,
it fails to show significant effect on the increase in CD4
cell counts during the 6-month follow-up. Findings of this
study suggest SMS program might be considered a key
component in comprehensive ART adherence support. Ideal
SMS program would be automated, easily customized and
bidirectional communication with medical providers while
maintaining confidentiality. Future studies should focus
on exploring the integration of SMS into clinical settings.
With the expansion of electronic medical records in clinical
settings, integration of SMS within existing hospital record
systems should be a priority of future research.
The authors would like to acknowledge all the physicians
and nurses in the HIV clinic of the Third People’s Hospital
of Hengyang, for their valuable input, designing the text
messages, and their cooperation in the recruitment. The
authors appreciate the active involvement of all the
participants in this study. We also acknowledge Professor Jane M
Simoni from the University of Washington, for helping us
revise the manuscript and giving us permission to use the
The authors report no conflicts of interest in this work.
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open access journal that focuses on the growing importance of patient
preference and adherence throughout the therapeutic continuum. Patient
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role in developing new therapeutic modalities and compounds to optimize
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