Health benefits from mobile app plus smart band wane once usage stops

A mobile health intervention combining a smartphone app, a smart band, and counseling offers benefits in terms of weight loss, body composition variables, and time spent in light physical activity compared to counseling alone at 3 months among sedentary adults with overweight or obesity, results of the Evident 3 Study have shown.

Once the devices have been collected, however, the downward trend is no longer sustained by the 12-month follow-up. Notably, the intervention is more effective in women, people aged ≥50 years, and married participants, according to the researchers.

In this randomized controlled, multicentre clinical trial, the researchers recruited a total of 650 participants from five primary care centres, of whom 318 were assigned to the intervention group (IG) and 332 to the control group (CG). At baseline visit, all participants received brief counseling regarding healthy diet and physical activity.

For 3 months, the IG received training to use the app and the smart band (Mi Band 2, Xiaomi). The researchers performed all measurements at baseline and at 3 and 12 months. They measured physical activity using the International Physical Activity Questionnaire–Short Form and assessed nutritional habits using the Food Frequency Questionnaire and Adherence to Mediterranean diet questionnaire.

Of the participants, 563 (86.6 percent) completed the 3-month visit and 443 (68.2 percent) accomplished the 12-month visit. [J Med Internet Res 2022;24:e30416]

At 12 months, the IG had greater reductions in weight (net difference [ND], ‒0.26 kg, 95 percent confidence interval [CI], ‒1.21 to 0.70; p=0.02), body mass index (BMI; ND, ‒0.06 points, 95 percent CI, ‒0.41 to 0.28; p=0.01), waist‒height ratio (ND, ‒0.25, 95 percent CI, ‒0.94 to 0.44; p=0.03), body adiposity index (ND, ‒0.33, 95 percent CI, ‒0.77 to 0.11; p=0.03), waist circumference (ND, ‒0.48 cm, 95 percent CI, ‒1.62 to 0.66; p=0.04), and hip circumference (ND, ‒0.69 cm, 95 percent CI, ‒1.62 to 0.25; p=0.03).

Both IG and CG had decreased daily caloric intake and increased adherence to the Mediterranean diet, with no significant between-group differences. Compared with CG, the IG had increased light physical activity time (32.6 min/week, 95 percent CI, ‒30.3 to 95.04; p=0.02).

In subgroup analyses, changes in body composition variables were observed in women, participants aged >50 years, and married people.

“The main findings of the use of a smartphone app in combination with an activity tracker wristband for 3 months and brief counseling showed a greater weight loss compared with the CG, but once these devices were collected, the trend was not maintained at 12 months,” the researchers said.

Previous meta-analyses revealed that mobile health weight loss interventions were effective relative to minimal intervention or control in the short term, but long-term results were inconclusive. [Obes Rev 2015;16:376-392; J Med Internet Res 2019;21:e12053]

Of note, women gained more benefits in terms of weight, BMI changes, and other anthropometric variables than men, potentially because of greater participation (n=445/650, 68.5 percent). In addition, women are more likely to join in weight loss interventions and use health apps. [Addict Behav 1994;19:147-158; J Med Internet Res 2015;17:e176]

“Further research is needed to determine the optimum intervention period to achieve greater results, as well as the inclusion of more tailored strategies in health apps and weight management interventions that improve intervention adherence and retention rates,” the researchers said.