Study protocol for a non-inferiority, multicenter, randomized study to evaluate a smartphone app-based follow-up program after bariatric surgery (BELLA plus trial).

INTRODUCTION: Adherence to follow-up (FU) care after bariatric surgery is poor despite strong recommendations. In our pilot Bella trial, we demonstrated that a completely remote follow-up program via smartphone is feasible and safe for patients after bariatric surgery. Building on this, we aim to verify our results in a multicenter, randomized controlled setting. METHODS: This trial plans to enroll 410 participants undergoing primary bariatric surgery in seven German bariatric centers. Participants are randomized into two groups: a control group receiving in-person FU according to the standard in the bariatric centers, and an interventional group monitored using a smartphone application (app). The app sends standardized questionnaires and reminders regarding regular vitamin intake and exercises. The built-in messaging function enables patients to communicate remotely with medical care professionals. After one year, all participants are evaluated at their primary bariatric centers. The primary outcome is weight loss 12 months after surgery. The secondary outcomes include obesity-related comorbidities, quality of life, serum values of vitamins and minerals, body impedance analysis, visits to the emergency department or readmission, patient compliance, and medical staff workload. DISCUSSION: The current study is the first prospective, individually randomized-controlled, multicenter trial where a mobile application completely replaces traditional in-person visits for post-bariatric surgery follow-ups in bariatric centers.

Remote Follow-up with a Mobile Application Is Equal to Traditional Outpatient Follow-up After Bariatric Surgery: the BELLA Pilot Trial.

PURPOSE: Medical follow-up after bariatric surgery is recommended. However, the compliance was poor. This study aimed to evaluate the feasibility of a smartphone-based fully remote follow-up (FU) program for patients after bariatric surgery. METHODS: In the interventional group, patients were followed up using a smartphone application (app), through which questionnaires were sent regularly. Participants in the control group underwent standard FU at the outpatient clinic every three months. After 12 months, all the participants were evaluated at an outpatient clinic. RESULTS: Between August 2020 and March 2021, 44 and 43 patients in the interventional and control groups, respectively, were included in the analysis after three patients were lost to FU, and three withdrew their informed consent because they wished for more personal contact with medical caregivers. After 12 months, total weight loss (TWL), %TWL, and percentage of excess weight loss (%EWL) did not differ between groups. There were no significant differences in the complication rates, including surgical complications, malnutrition, and micronutrition deficiency. The parameters of bioelectrical impedance analysis and quality of life did not differ between the groups. Vitamins and minerals in serum were similar in both groups except for calcium, which was significantly higher in the interventional group (2.52 mmol/L vs. 2.35 mmol/L, p = 0.038). CONCLUSION: Fully remote FU with a smartphone application is at least as effective as traditional in-person FU in an outpatient clinic after bariatric surgery. Through remote FU, patients can save time and medical professionals may have more resources for patients with more severe problems.

Smartphone application-based follow-up care of patients after bariatric surgery: A mixed-method study of usability.

Objective: Due to potential short-term and long-term complications, adequate lifelong follow-up is crucial for patients after bariatric surgery. However, compliance with postoperative follow-up is poor despite clear national and international guidelines. This feasibility trial aimed to evaluate the usability of a smartphone application-based follow-up program in patients after bariatric surgery. Methods: Patients were included after having undergone a primary bariatric surgery. Instead of attending meetings in our outpatient clinic, they were followed up using a smartphone application. After 6 months, the System Usability Scale (SUS) was used to measure participant perception. Additional interviews were performed to gain more insight into the usability of the app. Results: Between August 2020 and February 2021, 52 patients met the inclusion criteria and agreed to participate in the study, of whom 5 (9.6%) dropped out of the study. At the time of analysis, 31 patients have been followed up for 6 months, among whom 26 patients completed the SUS questionnaire. The mean overall score of SUS is 82.1 ± 19.8. In the qualitative analysis, participants were generally positive about the follow-up care and found it easy to use, despite some minor technical problems. Conclusion: Our smartphone app-based follow-up program was proven to be effective in the aftercare succeeding bariatric surgery. Our data indicates that the satisfaction, efficiency, learnability, and ease of use of the smartphone application were coherent in the acceptance and use of mobile technology by patients.