Periodic Text Messages Can Improve Daily Activity During Cardiac Rehab

Jessica Golbus, MD
Credit: Michigan Medicine

Personalized text messages could help promote physical activity among patients in cardiac rehabilitation, according to a new study.

An analysis of data from a randomized trial known as the VALENTINE study, results indicate contextually tailored text messages during the early stages of cardiac rehabilitation could help improve rates of physical activity,but investigators caution this effect varied based on time and device.¹

“Our study shows incredible promise for simple, low cost interventions delivered through mobile technology and their potential to help prevent secondary cardiovascular events in patients,” said study investigator Jessica Golbus, MD, assistant professor of internal medicine-cardiology at University of Michigan Medical School and member of the U-M Precision Health initiative.²

Named the Virtual Application-supported Environment to Increase Exercise (VALENTINE) study, the original trial assessed a mobile health intervention aimed at improving using delivered via a smartwatch. Although the trial failed to achieve its primary endpoint of a significant effect on outcomes at 6 months, secondary analyses pointed to evidence of device-specific benefits.^1,2

Within the intervention arm of the VALENTINE study was a microrandomized trial where patients were randomized 4 times per day over the 6-month trial to receive no text message or a message encouraging low-level physical activity. Investigators highlighted these messages were tailored based on 4 contextual factors: time of day, day of the week, weather, and time since enrollment.¹

Among the 220 patients included in the original trial, 112 participants were randomized to the intervention arm of the trial. These patients had a mean age of 59.5 (SD, 10.7) years, 32.4% were female, and 82.4% were White. Among this cohort, 63% owned an iPhone and were provided with an Apple Watch for study participation while the remaining 37% used a FitBit.¹

For Apple Watch participants, contextually tailored text messages led to a trend in increased step count by 10% in the 60-minutes following a message during days 1 to 30 (95% CI, −1% to 0%), with no effect from days 31 to 120 (1%; 95% CI, −4% to 5%), and a significant 6% increase during days 121 to 182 (95% CI, 0% to 11%). A subgroup analysis found no significant difference in results based on indication for cardiac rehabilitation.¹

For FitBit users, contextually tailored text messages significantly increased step count by 17% (95% CI, 7% to 8%) in the 60 minutes following a message during the first 30 days, but no effect was seen beyond this point. A subgroup analysis yielded similar results as the Apple Watch participants, with no significant difference in results based on indication for cardiac rehabilitation.¹

Investigators called attention to multiple limitations within their study. These included requiring all participants to own a compatible smartphone and other inclusion criteria, a relatively active cohort of participants, the inability to know when messages were delivered or read, and others.¹

“We learned a lot in this study on how patients could better use digital health tools like smartwatches in the future,” said senior investigator Brahmajee Nallamothu, MD, MPH, professor of internal medicine-cardiology at U-M Medical School.² “While the most consistent effects were seen in the first month after smartwatch use, this study was conducted will allow us to further narrow down on how different individuals are likely to be impacted. This is an incredibly exciting time in the field of mobile health technology.”

References:

1. Golbus JR, Shi J, Gupta K, et al. Text Messages to Promote Physical Activity in Patients With Cardiovascular Disease: A Micro-Randomized Trial of a Just-In-Time Adaptive Intervention. Circ Cardiovasc Qual Outcomes. 2024;17(7):e010731. doi:10.1161/CIRCOUTCOMES.123.010731
2. Fromson N. Physical activity improves early with customized text messages in patients with heart problems. Michigan Medicine. July 24, 2024. Accessed July 25, 2024. https://www.michiganmedicine.org/health-lab/physical-activity-improves-early-customized-text-messages-patients-heart-problems.