Short- and long-term effectiveness of a smartphone application for improving measures of adiposity: A randomised clinical trial – EVIDENT II study

Background: Evidence on the efficacy of smartphone applications (apps) for reducing body weight and other measurements of adiposity sustainably is not conclusive. Objective: To evaluate the effect of adding an app for 3 months to traditional counselling on physical activity (PA) and a heart-healthy diet for the modification of measurements of adiposity at 3 and 12 months after intervention. Methods: This randomised clinical trial included 833 subjects. The counselling and app group (IG) had 415 subjects, while 418 were included in the counselling only group (CG). The primary outcome was adiposity measurements at 3 and 12 months after intervention. The secondary outcome was the effect of the intervention by sex. Intervention: Counselling on a heart-healthy diet and PA was given to both groups. The IG also received training in the use of a smartphone app designed to promote a heart-healthy diet and PA, and this group was given access to this application for 3 months. Outcome measurements included waist circumference (WC), body mass index (BMI) and Clínica Universidad de Navarra – body adiposity estimator (CUN-BAE). Results: In the IG at 12 months, the following decreased: WC −0.72 cm (95% confidence interval [CI]: −2.35 to −0.02) and CUN-BAE −0.35 (95% CI: −0.63 to −0.06). These decreases were only observed in women. After baseline adjustment, the beneficial effect was maintained in the IG compared to the CG at 12 months in terms of WC (−0.67; 95% CI: −0.29 to −0.02) and CUN-BAE (−0.57; 95% CI: −1.10 to −0.04), but only in women. Conclusions: An intervention of nutritional counselling and PA plus the smartphone app with personalised recommendations compared to CG showed beneficial results in terms of reduction of abdominal obesity and the percentage of body fat in women, but not in men.

EVIDENT 3 Study: A randomized, controlled clinical trial to reduce inactivity and caloric intake in sedentary and overweight or obese people using a smartphone application: Study protocol

INTRODUCTION

Mobile technology, when included within multicomponent interventions, could contribute to more effective weight loss. The objective of this project is to assess the impact of adding the use of the EVIDENT 3 application, designed to promote healthy living habits, to traditional modification strategies employed for weight loss. Other targeted behaviors (walking, caloric-intake, sitting time) and outcomes (quality of life, inflammatory markers, measurements of arterial aging) will also be evaluated.

METHODS

Randomized, multicentre clinical trial with 2 parallel groups. The study will be conducted in the primary care setting and will include 700 subjects 20 to 65 years, with a body mass index (27.5-40 kg/m), who are clinically classified as sedentary. The primary outcome will be weight loss. Secondary outcomes will include change in walking (steps/d), sitting time (min/wk), caloric intake (kcal/d), quality of life, arterial aging (augmentation index), and pro-inflammatory marker levels. Outcomes will be measured at baseline, after 3 months, and after 1 year. Participants will be randomly assigned to either the intervention group (IG) or the control group (CG). Both groups will receive the traditional primary care lifestyle counseling prior to randomization. The subjects in the IG will be lent a smartphone and a smartband for a 3-month period, corresponding to the length of the intervention. The EVIDENT 3 application integrates the information collected by the smartband on physical activity and the self-reported information by participants on daily food intake. Using this information, the application generates recommendations and personalized goals for weight loss.

DISCUSSION

There is a great diversity in the applications used obtaining different results on lifestyle improvement and weight loss. The populations studied are not homogeneous and generate different results. The results of this study will help our understanding of the efficacy of new technologies, combined with traditional counseling, towards reducing obesity and enabling healthier lifestyles.

ETHICS AND DISSEMINATION

The study was approved by the Clinical Research Ethics Committee of the Health Area of Salamanca ("CREC of Health Area of Salamanca") on April 2016. A SPIRIT checklist is available for this protocol. The trial was registered in ClinicalTrials.gov provided by the US National Library of Medicine-number NCT03175614.