Weight-Loss and Metabolic Outcomes of a Swallowable Fluid-Filled versus an Adjustable Intragastric Balloon in Adults with Overweight or Obesity: A Retrospective Single-Center Study with 12-Month Weight Outcomes

INTRODUCTION: Intragastric balloons (IGBs) improve weight and metabolic parameters, but structurally different devices are rarely compared within one center and are conventionally assessed at very different time points. We compared a swallowable fluid-filled IGB with an adjustable IGB, both at the end of treatment and at a common 12-month horizon.

MATERIALS AND METHODS: Retrospective single-center analysis of adults completing IGB treatment. Weight, glycated hemoglobin (HbA1c), fasting glucose, lipid profile and blood pressure were recorded before and at the end of treatment; weight was also recorded 12 months after placement. The primary outcome was percentage total weight loss (%TWL) at end of treatment. Between-device differences were adjusted for baseline value, age, sex, diabetes and dyslipidemia and by propensity weighting, and metabolic comparisons were corrected for multiple testing.

RESULTS: Of 357 patients treated, 239 were analyzed (133 swallowable, 106 adjustable; 76.6% women); attrition before analysis was far higher in the adjustable group (48.5% vs. 11.9%). Both devices reduced weight, HbA1c and atherogenic lipids and raised high-density lipoprotein cholesterol. At end of treatment the adjustable balloon achieved greater %TWL (10.2 ± 4.2% over ≈ 12 months vs. 8.9 ± 4.0% over ≈ 4 months; adjusted difference 1.27%, 95% CI 0.20 to 2.34). At 12 months, swallowable-group %TWL had fallen to 6.6 ± 7.1% and the difference widened to 3.6% (95% CI 2.2 to 5.1). No between-device difference in metabolic change survived correction for multiple testing. A tipping-point analysis showed the end-of-treatment difference to be fragile to the observed attrition, whereas the 12-month difference was not.

CONCLUSION: Both IGBs produced meaningful weight loss and metabolic improvement, but comparison between them is strongly time-dependent: the swallowable balloon's short-term advantage per month of dwell was not maintained at 12 months. Incomplete adjustable-group follow-up means the device comparison should be read as an upper bound. Metabolic improvement was similar between devices and not proportional to weight loss.