JMIR Publications

ABSTRACT

Background:

Effective treatment of obesity in children and adolescents traditionally requires frequent in-person contact and is often limited by low participant engagement. Mobile health tools may offer alternative models that enhance participant engagement.

Objective:

To assess participant engagement in a mobile application-based health-behavior change weight management program, which included health coaching via video chat, and to examine the association between that engagement and change in weight status.

Methods:

A retrospective cohort study of participant-reported data from users of Kurbo, a commercial program that provides weekly individual coaching via video chat, and supports self-monitoring of health behaviors through a mobile application. Study participants included all users, between March 2015 and March 2017, who were 5-18 years old and who were overweight or obese (BMI > 85th percentile) upon initial use. The primary outcome was the total number of health coaching sessions received. Secondary outcomes included other measures of participant engagement (retention, participation period, coaching messages, dietary logs, physical activity logs) and change in weight status (change in %BMIp95). Analyses of baseline and outcome measures were conducted across three groups, based on each participant’s initial commitment period: 4 weeks, 12-16 weeks, or 24-weeks. Most participants voluntarily chose their commitment period, but a subset were involuntarily assigned to the 12-16 week period by an employer or health plan. Multivariable linear regression models were constructed to adjust outcomes for participant age and sex. Sensitivity analyses were conducted, excluding participants involuntarily assigned to the 12-16-week group.

Results:

1120 participants were included in analyses. At baseline, participants had a mean age of 12 years (SD 2.5), mean BMI percentile of 96.6 (SD 3.1), and were predominantly female (68%). Participant distribution across commitment periods was 292 (26.1%) for 4 weeks; 690 (61.6%) for 12-16 weeks; and 138 (12.3%) for 24 weeks. 895 participants (79.9%), remained in the program for at least the duration of their commitment period. The median coaching sessions (IQR) received were 8 (3-16) for the 4-week group, 9 (5-12) for the 12-16 week group, and 19 (11-25) for the 24-week group (p<0.001). Age and sex adjusted beta-coefficients (95% CI) for coaching sessions were -8.05 (-10.22 to -5.89) for 4 weeks and -9.35 (-11.31 to -7.4) for 12 weeks, compared to reference group of 24 weeks (p < 0.001). Adjusted for age and sex, the overall mean change in %BMIp95 (95% CI) was -0.21 (-0.25 to -0.18) per additional coaching session (p < 0.001).

Conclusions:

Among overweight and obese children using a mobile application-based behavior change program, program retention was high, with increased engagement associated with longer voluntary commitment periods. Engagement with coaching sessions was also associated with decreases in weight status.