Abstract 12260: The SMARTER Trial: Is Engagement With Mhealth Better With Daily Feedback to Self-Monitoring Compared to No Feedback?

Abstract

Introduction: Self-monitoring (SM) is the cornerstone of behavior change for weight loss as is providing feedback (FB) to SM. FB to SM can be delivered remotely and in real time. Hypothesis: Participants assigned to SM+FB will show greater engagement in the weight loss intervention, as measured by adherence to dietary goals, than the SM group. Methods: SMARTER was a 2-arm trial that randomized 502 adults aged ≥18 years with a body mass index (BMI) 27-43 kg/m 2 to 1) self-monitoring of diet and physical activity with up to 3 daily FB messages (SM+FB: n=251) or 2) self-monitoring only (SM: n=251). Daily calorie goals were based on baseline body weight and gender; the fat goal was 25% of caloric intake. Monthly adherence to calorie and fat goals were defined as number of days with intake within 85% -115% of daily goals divided by number of valid days (≥15 days with ≥50% of daily goals recorded) multiplied by 100%. Linear mixed modeling with random intercept and slope was used to examine the effect of treatment assignment on adherence over 12 months. Results: Participants were predominantly female (79%) and White (83%) with a mean age of 45±14.4 years and a mean BMI of 33.7±3.96 kg/m 2 . Monthly percentages of days adherent to calorie goal (b [95% CI]: -2.07 [-3.58, -0.56], b^2: 0.34 [0.08, 0.59], b^3: -0.02 [-0.03, -0.01], all P<.05 ) and fat goal (b: 2.14 [1.03, 3.25], b^2: -0.31 [-0.50, -0.12], b^3: 0.01 [0.003, 0.02], all P<.05 ) decreased curvilinearly over time. On average, SM+FB had greater monthly percentages of days adherent to calorie goal (4.42 [0.41, 8.45], P=.03 ) and fat goal (3.90 [1.44, 6.36], P<.05 ) than SM. Moreover, the rate of decline in monthly percentages of days adherent to calorie (b: -1.98 [-3.03, -0.93], b^2: -0.14 [0.06, 0.22], all P<.05 ) and fat (b: -1.18 [1.94, -0.42], b^2: 0.10 [0.04, 0.16], all P<.05 ) goals were non-linear but different between groups. Conclusions: Personalized FB messages were effective in promoting adherence to dietary goals; however, overall engagement with the intervention was low, which may explain small between group differences.