Mobile Phone Text Messages to Support Treatment Adherence in Adults With High Blood Pressure (StAR): A Single-Blind, Randomized Trial
Background—We assessed the effect of automated treatment adherence support delivered via mobile-phone short message system (SMS) text-messages on blood pressure.
Methods and Results—In this pragmatic single-blind, three-arm randomized trial (StAR), undertaken in South Africa, patients treated for high blood pressure were randomly allocated in a 1:1:1 ratio to information-only or interactive SMS text-messaging, or usual care. The primary outcome was change in systolic blood pressure at 12-months from baseline measured with a validated oscillometric device. All trial staff were masked to treatment allocation. Analyses were intention to treat. Between June 26, 2012 and November 23, 2012, 1372 participants were randomized to receive information-only SMS text-messages (n=457), interactive SMS text-messages (n=458), or usual care (n=457). Primary outcome data were available for 1256 (92%) participants. At 12-months, the mean adjusted change (95% CI) in systolic blood pressure compared to usual care was -2.2 mm Hg (-4.4 to -0.04) with information-only SMS and -1.6 mm Hg (-3.7 to 0.6) with interactive SMS. Odds ratios (95% CI) for the proportion of participants with a blood pressure <140/90mm Hg were for information-only messaging 1.42 (1.03 to 1.95) and for interactive messaging 1.41 (1.02 to 1.95) compared to usual care.
Conclusions—In this randomized trial of an automated adherence support program delivered by SMS text-message in a general outpatient population of adults with high blood pressure, we found a small, reduction in systolic blood pressure control compared to usual care at 12-months. There was no evidence that an interactive intervention increased this effect.
Clinical Trial Registration Information—ClinicalTrials.gov. Identifier: South African National Clinical Trials Register number (SANCTR DOH-27-1212-386); Pan Africa Trial Register (PACTR201411000724141).
- Received May 28, 2015.
- Revision received December 16, 2015.
- Accepted December 23, 2015.
Circulation is published on behalf of the American Heart Association, Inc., by Wolters Kluwer. This is an open access article under the terms of the Creative Commons Attribution Non-Commercial License (http://creative commons.org/licenses/by-nc/3.0/), which permits use, distribution, and reproduction in any medium, provided that the original work is properly cited and is not used for commercial purposes.