1. mHEALTH to Improve Health: Effectiveness of a weekly text messaging intervention to improve ART adherence and HIV Viral Load: WelTel OAKTREE.
M.C.M. Murray1,2,3, K. Friesen2, S. O’Shaughnessy2, A. Albert3, E.J. Maan2, N. Pick2,3,4, A. Alimenti2,5, M. Kestler1,2, K. Smillie6,
D. Money2,3,7, R. Lester1, WelTel OAKTREE Study Team.
Poster number: WEPED849
University of British Columbia, Medicine, Division of Infectious Diseases, Vancouver, Canada, (2) Oak Tree Clinic, British Columbia Women's Hospital, Vancouver, Canada, (3) Women's Health Research Institute, Vancouver, Canada, (4) University of British Columbia, Medicine, Vancouver, Canada, (5) University of British Columbia, Department of Pediatrics, Vancouver, Canada, (6) British Columbia Centre for Disease Control, Vancouver, Canada, (7) University of British Columbia, Department of Obstetrics and Gynecology, Vancouver, British Columbia.
Background
Methods
Antiretroviral therapy (ART) improves health and survival of HIV-positive (HIV+) individuals. However, engagement in care and medication adherence are essential to prevent resistance, morbidity and mortality. Despite widespread availability of ART for HIV treatment in Canada, many HIV+ individuals struggle with adherence issues not improved with conventional interventions. In a randomized controlled trial in Kenya, (WelTelKenya1), a weekly mHealth (mobile phone technology for health care) intervention improved ART adherence and HIV viral load (VL) suppression (Lester et al., Lancet 2010). We conducted a repeated measures study using the WelTel model to examine effectiveness of this weekly interactive text-messaging intervention on improving ART adherence and VL in British Columbia.
To examine effectiveness of the WelTel intervention to improve engagement and outcomes for vulnerable and hard to reach HIV+ patients as measured by:
1) Change in HIV log10 VL from control year to study end.
2) Change in mean population log10 VL (control year to intervention year)
3) CD4 count change (control year to intervention year)
4) Change in antiretroviral adherence (control year to intervention year)
5) Participant attendance at outpatient visits (control year to intervention year)
Participants: 81 HIV+ participants, qualify for ART; with CD4<500, HIV VL >200 copies/mL and considered ‘vulnerable’ by the clinical team (at least one of: unstable housing, active addiction, domestic violence, poor care engagement or adherence, advanced HIV infection/AIDS, or mental health factors).
Study Period and Setting: April 2013 to May 2015, Oak Tree Clinic, Vancouver, Canada.
Intervention: Participants who did not have a cell phone were given one with unlimited texting capability. Participants then received a weekly interactive SMS/text message check-in on their health status stating “How are you?” for one year. A clinic nurse triaged responses.
Data Collection: Demographic data, CD4 counts, VL, adherence, and appointment attendance, were collected for control and intervention years. Adherence data was obtained from pharmacy refill records and patient report.
Analysis: Repeated measures mixed-effects linear regression took into account repeated measures on the same subject from pre-study to intervention years. Linear regression was used for CD4 count and VL (log10 transformed), while logistic regression was used for ART adherence and appointment attendance (Table 2). The Wilcoxon rank sum test with continuity correction was used to assess change in mean and median log10 HIV VL from control to intervention years (Figure 1a) and from the control year to study end (Figure 1b).
Objective
Results
TABLE 1
Participant Demographics (n=81)
N (%)
Gender
Female
Male
Transgender
73 (90.1%)
6 (7.4%)
2 (2.5%)
Age (years)
Median (Range)
39.4 (15-61)
Ethnicity
Caucasian
Aboriginal
Black
South Asian
31 (38.3%)
27 (33.3%)
18 (22.2%)
5 (6.2%)
Income
Disability
Welfare
Employed
Other
58 (71.6%)
4 (5.0%)
13 (16.0%)
Cell phone ownership
(baseline)
Yes No
43 (53.1%)
38 (46.9%)
Baseline CD4
350 (10-490)
FIGURE 1a
FIGURE 1b
Patient receives text message: “How are you?” OK
Problem
No Response
(at 48 hrs)
Clinician calls back to TRIAGE as needed:
Provide counseling
Provide advice
Refer to clinic/hospital
Patient OK
Follow-up text from clinician
WelTel Intervention
Figure 1: Box plots of mean population log10 VL in the control year vs. intervention year (1a); and of the control year vs. study end (1b). Using the Wilcoxon rank sum test there is a trend toward significance between years (p=0.087), and a significant decrease in log10 VL at study end (p=0.007)
FIGURE 2
TABLE 2
Effectiveness
Measure
Control Year
Intervention Year
Coefficient
P-value
Mean log10 HIV
Viral Load
2.92
2.57
-0.26
0.015
Mean CD4 Count
(cells/mm3)
345.2
356.5
0.005
0.74
ART Adherence
(predicted mean %
doses taken)
67.1%
70.0%
0.13
<0.0001
Appointment
Attendance
51.9%
48.2%
-0.15
0.12
FIGURE 3
Figure 2: Box plots of percent adherence during control and intervention years and percent change in adherence between years stratified by study end VL <40 or >40.
There is a significant difference in adherence in terms of viral load levels during control (p=0.004), study (p<0.0001) years as well as the % adherence of overall difference between the years (p=0.005).
Patients with an undetectable VL at study end had higher rates of adherence and lower viral loads in the control year.
There was a 0.26 log decrease in the population mean HIV viral load from the control year to the intervention year.
At study end VL was <40 in 35/78 participants (with a VL in the intervention year), and <200 in 46/78.
Figure 3: Box plots of VL in control year stratified by end- study log10 VL. Kruskal Wallis results: X2(1)=5.22, p=0.02.
Conclusions
Population VL decreased significantly from control to intervention year, and from control year to study end.
ART adherence improved significantly from control to intervention year, though no change was seen in CD4 count or appointment attendance.
Those with undetectable HIV VL at study end had higher ART adherence and lower VL at baseline than those who did not.
Results suggest the WelTel intervention is an effective tool for reducing HIV VL load and improving ART adherence in poorly engaged, vulnerable Canadian populations.
The Study was funded through an unrestricted grant by Gilead and with support from Telus.
Thank you to study participants for their valuable input.
For more information please contact Dr. Melanie Murray at or Dr. Richard Lester at