abiliti Closed-Loop Gastric Electrical Stimulation System for Treatment of Obesity: Clinical Results with a 27-Month Follow-Up

Abstract

Background: The aim of the study was to evaluate the safety and effectiveness of a novel closed-loop gastric electric stimulation device (abiliti system) featuring a transgastric sensor to detect food intake and an accelerometer to record physical activity to induce and maintain lifestyle changes to treat obesity.

Methods: In a prospective, multi-center study, 34 obese subjects (BMI of 42.1 ± 5.3 kg/m(2)) who passed an eligibility evaluation were implanted with the abiliti system. Safety evaluation included an endoscopic exam to assess the intragastric electrode healing. Efficacy evaluation at 1 year of therapy included weight loss, improvements in eating, and exercise behavior and quality of life.

Results: The transgastric implant controlled by endoscopy was stable for all participants. At 12 months (12 M) the mean excess weight loss (EWL) was 28.7% (95%CI, 34.5 to 22.5%), and mean reduction in BMI was 4.8 ± 3.2 kg/m(2). At 27 months (27 M), the EWL was 27.5% (95% CI, 21.3% to 33.7%). Eating behavior, evaluated by the "Three Factor Eating Questionnaire", showed a significant increase in the cognition factor and decrease in the disinhibition and hunger factors at 12 M in comparison to baseline (p < 0.001). Participants significantly increased their weekly physical activity (p < 0.001). Quality of life was improved in 55.2% of the patients.

Conclusions: Gastric electrical stimulation with abiliti system in obese participants is well tolerated and leads to significant 12 M weight loss, which was stable to 27 M. We suggest that weight loss is achieved due to the assessed alteration of eating behavior in particular the reduction in disinhibition and hunger, and the measured increase in physical activity.

Trial registration: ClinicalTrials.gov NCT01539850.

Figures

Fig. 1

The transgastric sensor detects food entry into the stomach and then triggers the gastric stimulator to deliver therapy at the lesser curvature in the location of the “crow’s foot”

Fig. 2

Weight loss outcomes: %EWL at 3, 6, 9, and 12 months (mean ± 95 % CI, n = 31), and Individual BMI change at 12 months (n = 31) each line segment represents the change in BMI for each subject from baseline to 12 months, showing no correlation between baseline BMI and reduction achieved

Fig. 3

%EWL ± 95%CI throughout the 27 months, with the number of patients remaining in the study at each follow-up indicated with the corresponding bar

Fig. 4

The weekly exercise (min/week) is shown for high performers (a EWL ≥ 25, N = 18) and lower performers (b EWL < 25, N = 13) groups at baseline, 3, 6, and 12 months. The higher performing group exercised consistently between months 3 and 12, at a higher level than baseline, while the low performing group also maintained a higher exercise level compared to baseline, but between M3 and M12 showed a linear decrease (R2 = 0.97) in exercise

Fig. 5

Change in overall QOL score and key area scores from baseline to 12 months. From baseline to 12 months, the overall quality of life improved for 16 subjects (55.17 %), remained the same for 10 (34.48 %) and declined for 3 (10.34 %). Analyzing individual key area scores, four areas were significantly improved at 12 months, self esteem, physical, sexual, and focus on eating (p < 0.001)