Jessica R. Golbus

BACKGROUND Physical activity is essential for heart failure (HF) management, yet most patients are not adequately active. Mobile health interventions grounded in self-determination theory (SDT) hold promise for supporting physical activity but are insufficiently tailored to the unique needs of patients with HF. OBJECTIVE This study aimed to identify barriers, facilitators, and motivations for physical activity in patients with HF and to iteratively develop and evaluate SDT-informed mHealth intervention components—including messages and user interface prototypes—through a sequential HCD process. METHODS We conducted a three-phase human-centered design (HCD) study with HF patients. Phase 1 involved focus groups identifying barriers, facilitators, and motivations for physical activity. Phase 2 evaluated prototype messages (e.g., gentle reminders, context-tailored messages) and user interfaces. Phase 3 used A/B-style testing to compare refined message variations. All phases were grounded in SDT and motivational interviewing principles. Transcripts were thematically coded by three investigators. RESULTS Eight participants (mean age 66 years [SD 10.6]; 50% women) completed all three HCD sessions. A universal theme emerged: unpredictable daily fluctuations in perceived ability driven by physiological (e.g., fatigue, dyspnea) and psychological (e.g., low vitality, perceived competence) barriers. These required distinct approaches. Physiological barriers necessitated validation and permission to rest, while psychological barriers benefited from autonomy-supportive prompts encouraging reflection on personal goals and values. Participants identified "windows of opportunity" for re-engagement following low-ability days. Caregiving responsibilities functioned paradoxically as both barriers and motivators. In A/B-style testing, participants strongly preferred contextually tailored messages promoting self-reflection over prescriptive directives. CONCLUSIONS Mobile health interventions for HF require dynamic, context-aware tailoring that distinguishes physiological from psychological barriers, leverages temporal windows of opportunity, and supports autonomy. This HCD approach successfully operationalized SDT principles into acceptable intervention components, providing a foundation for pilot testing and future efficacy trials.

Background: Achieving adequate blood pressure control is challenging for patients and clinicians. Digital hypertension management solutions that use push notifications to promote lifestyle management have been proposed as an approach, but their effectiveness remains unknown. Objective: This analysis was designed to interrogate the independent and short-term effects of push notifications, tailored to participant and environmental factors, and on physical activity levels and sodium intake among individuals with hypertension. Methods: The myBPmyLife study was a 6-month randomized controlled trial of participants with self-reported hypertension recruited from an academic medical center and federally qualified health centers. A core component of the intervention consisted of microrandomized push notifications promoting lifestyle modifications that were randomly delivered at 4 daily time points and focused on physical activity and dietary sodium intake. Our primary outcome for this secondary analysis was the step count 60 minutes after a physical activity notification and lower-sodium food choices 24 hours after a dietary notification. This analysis focuses on the results of the microrandomized trial and used a centered and weighted least squares method adapted for 2 or more treatments. Results: A total of 298 participants were randomized to the intervention arm, of whom 287 had data available for analysis. Participants’ mean age was 59.5 (SD 13.1) years, 138 (48.1%) were women, and 206 (71.8%) were White. Participants were randomized at 187,517 time points over 6 months, which led to 0.96 (SD 0.86) push notifications per day divided between activity (50.4%; SD 0.4) and dietary (49.8%; SD 0.4) notifications. Activity notifications did not increase step count in the 60 minutes after a notification (estimate 1.01, 95% CI 0.98‐1.04; P =.40). Similarly, dietary notifications did not impact the number of lower-sodium food choices in the subsequent 24 hours (estimate 0.93, 95% CI 0.83‐1.04; P =.23), but in exploratory post hoc analyses, did increase mobile app use by 95.5% (95% CI 1.81‐2.10; P <.001), mobile app clicks or searches by 93.7% (95% CI 1.72%‐2.16%; P <.001), and low sodium searches by 113.0% (95% CI 1.73‐2.53; P <.001), all within 60 minutes. Conclusions: In patients with hypertension, push notifications did not impact short-term physical activity levels or dietary sodium intake but did improve intervention engagement.

BACKGROUND: Anecdotal evidence suggests that symptoms and physical activity levels in patients with heart failure (HF) fluctuate considerably, though empirical data to support this claim are sparse. We examined how stable psychosocial traits (eg, intrinsic motivation), situational psychosocial states (eg, vitality), and HF symptoms vary in stable patients with HF and their association with physical activity. METHODS: The MOVIN-HF study (Mobile Health Intervention to Increase Activity in Heart Failure) was a prospective, observational study of patients with symptomatic HF. We collected data on (1) psychosocial traits at baseline and (2) twice daily ecological momentary assessments for 28 days of participants’ symptoms and current psychosocial states. Physical activity was measured by smartwatch step counts. We evaluated the association between baseline psychosocial states and mean daily step counts and between ecological momentary assessments of symptoms and psychosocial states and short-term step counts (12 hours after ecological momentary assessments). Mixed effects models quantified associations. RESULTS: Between February and June 2024, 30 participants enrolled in the study; the mean age was 59.7 (SD, 13.6) years, 53% were female, and most (63%) had New York Heart Association class 2 HF symptoms. Baseline psychosocial traits like motivational quality were significantly associated with daily step count. For example, each 1-point increase in intrinsic motivation was associated with 39% higher daily step count (95% CI, 3%–87%). There was also significant variability in ecological momentary assessment scores of symptoms and psychosocial states: 10 (33%) participants experienced a 50% or greater change in HF symptoms, and 18 (60%) a 50% or greater change in vitality. HF symptoms and psychosocial states (eg, vitality, competence) were significantly associated with 12-hour step count. CONCLUSIONS: Baseline psychosocial traits are associated with daily physical activity. In addition, symptoms and psychosocial states fluctuate frequently among patients with HF and are associated with short term physical activity. These findings suggest tailored interventions may improve physical activity levels.

Background: Efforts to improve diversity in clinical trials often prioritize recruitment based on broad demographic factors. This approach may overlook the influence of community context and health-related social needs on health behaviors, including sodium intake, a key modifiable risk factor for hypertension and cardiovascular disease. Objective: This study aims to assess the impact of enrollment site, sociodemographic factors, and health-related social needs on baseline dietary sodium intake among participants in a mobile health clinical trial aimed at lowering blood pressure. Methods: The myBPmyLife study is a prospective, randomized controlled trial evaluating a mobile health intervention to lower blood pressure through increased physical activity and lower sodium food choices. Participants with hypertension were recruited from a university health system and a federally qualified health center (FQHC). All participants completed a validated sodium screener at enrollment. Sociodemographic data and health-related social needs were self-reported. Univariable and multivariable linear regression models were used to evaluate the associations between sodium intake and participant characteristics. This analysis presents a cross-sectional examination of the baseline characteristics of participants enrolled in the myBPmyLife study. Results: Among 600 included participants, 96 (16.0%) were from the FQHC. Mean age was 60.1 (SD 13.5) years; 48.2% (289/600) were women, and 13.0% (78/600) were Black. FQHC participants were significantly younger (mean age 47.9, SD 11.1 vs 62.5, SD 12.7 years), more likely to be Black (43/96, 44.8% vs 35/504, 6.9%), and 8.5 times more likely to have difficulty paying for their health-related social needs. Mean baseline sodium intake was 3082.3 (SD 1072.5) mg/day, with 85.5% (513/600) of participants exceeding the World Health Organization’s recommended daily sodium limit. Baseline sodium intake was significantly higher for FQHC participants (mean difference 381.1, SD 1064.2 mg/d; 95% CI 84.5-677.7; P=.01), men (mean difference 543.9, SD 1038.3 mg/d; 95% CI 377.3-710.5; P<.001), Black participants (mean difference 442.5, SD 1043.4 mg/d; 95% CI 119.7-765.3; P=.008) and those with difficulty affording basic needs (mean difference 338.1, SD 1066.7 mg/d; 95% CI 95.2-581.0; P=.02). Sodium intake was lower in older participants (−196.4 mg/d per 10 years; 95% CI −258.0 to −134.9; P<.001). In a multivariable analysis, age, gender, and race remained independently associated with sodium intake, while differences by site and health-related social needs were not statistically significant. Conclusions: Differences in sodium intake were observed across sociodemographic groups. While the enrollment site was not independently associated with sodium intake after adjustment, it played a role in shaping the participant population, evidenced by the differences in demographics and health-related social needs among participants based on enrollment site. These findings underscore the importance of recruiting from distinct clinical settings to capture a range of contextual factors that influence health behaviors. Clinical trials aiming for representativeness should consider both individual- and community-level factors during recruitment to more accurately inform interventions and health outcomes.

Background: Although telehealth cardiac rehabilitation (CR) may improve access, there are concerns about its long‐term effectiveness and impact on equity as compared with in‐person CR. Our objective was to tailor a patient‐centered telehealth CR program for diverse populations. Methods: CR patients and caregivers were recruited between January and September 2023 from 4 US academic medical centers. Participants engaged in human‐centered design sessions to iteratively refine a telehealth CR program. Sessions had planned topics, but there was variation across sites to account for site‐specific needs and participant feedback. Sessions were qualitatively analyzed using rapid template analysis with preselected behavioral science constructs and other emergent codes. Results: The study included 21 participants (71% aged ≥60 years, 48% women, 62% non‐Hispanic White individuals; 90% CR patients, 10% CR caregivers). Participants thought that telehealth CR could be helpful for personalized support at home and convenience but recognized that technology is not always easy to use. Some expressed concerns about the safety of telehealth CR, especially at the beginning, and desired monitoring through a mobile device or video observation of exercise. Safety protocols and technology training were developed, which addressed concerns about telehealth CR. Opportunities for social support with telehealth CR were also desired. From these findings, an implementation toolkit was developed, including a graphic program description, safety plan, home exercise plan for during and after CR, and scripts for technology training and individual and group telehealth visits. Conclusions: A patient‐centered telehealth CR program and implementation toolkit were systematically tailored to address the needs of diverse populations.

Background: Emerging data suggest that text message–based mobile health interventions may enhance physical activity levels in patients with cardiovascular disease enrolled in cardiac rehabilitation. The optimal characteristics of texts that lead to maximal patient engagement and drive meaningful behavioral change are not well understood. Objective: This study aimed to understand how text- and participant-level characteristics impact physical activity levels after text delivery. Methods: The VALENTINE (Virtual Application-Supported Environment to Increase Exercise) study was a randomized controlled trial designed to evaluate a mobile health intervention delivered to low- and moderate-risk adults enrolled in cardiac rehabilitation. Embedded within this study was a microrandomized trial focused on the effect of texts on physical activity levels among intervention participants. Participants in the intervention group received texts through a smartwatch (Apple Watch or Fitbit Versa) that were tailored to the time of day, day of the week (weekday vs weekend), weather, and time since enrollment in cardiac rehabilitation. Texts also differed in content type (walking vs antisedentary) and in the level of personalization (inclusion of the participant’s name or not). Delivery was randomized at 4 user-selected time points daily, with participants having a 25% probability of receiving a text at any time point. The primary outcome was step count 60 minutes after a decision point. This analysis focuses on the text- and participant-level factors that moderated the intervention’s effect on the primary outcome. Given potential measurement differences determined a priori, analyses were stratified by device type and phase of cardiac rehabilitation and adjusted for age, sex, and baseline activity status using a generalization of regression analysis. Results: More than 70,552 randomizations occurred in 108 participants (mean age 59.5, SD 10.7 years; n=36, 33.3% female; n=19, 17.6% non-White; n=68, 63% Apple Watch users) over 6 months. Overall, no text characteristics (including personalization with the participant’s name) or participant characteristics (including baseline physical activity) consistently impacted text responsiveness for either device type. Although the findings were not consistently significant between device types and across phases of the trial, there was a trend toward increased responsiveness to texts that promoted walking (compared to antisedentary texts) and that were delivered to younger (aged <65 years) and male participants. Conclusions: In this randomized clinical trial, we found that tailored texts improved physical activity levels among cardiac rehabilitation enrollees in the initiation phase, but this effect was not explained by text- or participant-level moderators. Additional work is needed to explore the impact of tailoring based on an extended set of personal and environmental factors to optimize the delivery and efficacy of text message–based interventions. Trial Registration: ClinicalTrials.gov NCT04587882; https://clinicaltrials.gov/study/NCT04587882 International Registered Report Identifier (IRRID): RR2-10.1016/j.ahj.2022.02.012