An Adaptive Text Message Intervention to Promote Well-Being and Health Behavior Adherence for Patients With Cardiovascular Disease: Intervention Design and Preliminary Results

Abstract

Background: Most individuals with heart disease struggle to adhere to cardiovascular health behaviors, despite their known health benefits. Text message interventions (TMIs) are a promising treatment modality for health behavior promotion, but existing TMIs typically deliver a fixed set of messages and do not target well-being constructs associated with adherence and cardiovascular health.

Objective: To develop a 4-week TMI, which delivers daily messages to promote well-being and adherence to health behaviors and dynamically adapts based on participant feedback to deliver increasingly customized messages; and to assess its feasibility, acceptability, and preliminary efficacy in a single-arm, proof-of-concept trial in 14 individuals with coronary artery disease (age mean = 67.9, standard deviation = 8.7).

Methods: Participants received daily text messages related to well-being, physical activity, or diet, rated each message's utility, and these ratings informed the TMI's choice of future text messages. Feasibility was assessed by the proportion of messages successfully sent, and acceptability was assessed by participant ratings of intervention burden and text message utility. Finally, the intervention's preliminary efficacy was explored by measuring pre-post changes in psychologic and behavioral outcomes.

Results: The TMI was both feasible (93% of participants received all messages) and well-accepted (mean text message utility: 7.0 of 10 [standard deviation 2.5]; mean intervention utility: 6.4 of 10 [standard deviation 0.9]; mean intervention burden: 0.5 of 10 [standard deviation 0.9]). Participants reported that messages related to well-being were particularly helpful and that most messages led to an action (e.g., eating more vegetables, being kind to others). The TMI led to nonsignificant, small-to-medium effect size improvements in happiness, optimism, determination, depression, anxiety, self-rated health, and diet (d = 0.19-0.48), and, unexpectedly, small reductions in activity and physical function (d = -0.20 and -0.32).

Conclusions: The adaptive TMI was feasible, well-accepted, and associated with nonsignificant improvements in psychologic outcomes and mixed effects on behavioral outcomes. Larger, well-powered studies are needed to determine whether this TMI will be able to improve well-being and health-related outcomes in this high-risk population.

Keywords: diet; health behavior adherence; physical activity; text messaging; well-being.

Figure 1.

Text message algorithm * Utility ratings from participants were transformed from a 0–10 scale to a −5 to +5 scale, so that scores below 5 reduced the likelihood of receiving messages with an attribute, and scores above 5 increased the likelihood of receiving messages with that attribute. In this example, the participant’s rating of 8 was transformed to a score of +3.

Figure 2.

Flow of participants Dr. Celano has received salary support from BioXcel Pharmaceuticals and honoraria for talks to Sunovion Pharmaceuticals on topics unrelated to this research. The authors report no proprietary or commercial interest in any product mentioned or concept discussed in this article.