Is All Weight Loss Equal Following Sleeve Gastrectomy? Defining Body Composition and Anthropometric Thresholds for Hyperglycemia Remission in Women from a Prospective Cohort Study.

INTRODUCTION

Adiposity magnitude and distribution strongly influence the risk of prediabetes and type 2 diabetes (T2D). While metabolic bariatric surgery provides durable weight loss and metabolic improvement, optimal anthropometric and body composition targets for hyperglycemia remission remain undefined.

METHODS

We conducted a prospective cohort study of women undergoing sleeve gastrectomy (SG) in Melbourne, Australia (2019–2022). Anthropometric, biochemical, and dual-energy X-ray absorptiometry (DXA) derived body composition data were collected at baseline and 12 months post-surgery. The primary outcome was change in body composition. Secondary outcomes included percentage total body weight loss (%TBWL), fat-mass loss, and central adiposity thresholds associated with hyperglycemia remission, defined as HbA1c < 6.0% or fasting glucose < 6.0 mmol/L without medications.

RESULTS

Of 50 patients recruited, 39 completed the study. Marked reductions in fat mass and central adiposity were observed. All seven participants with T2D achieved hyperglycemia remission; five discontinued hypoglycemic therapy. Among those with prediabetes/T2D (n = 14), 93% achieved hyperglycemia remission. ROC analyses identified candidate thresholds associated with remission, including ≥ 21.9% TBWL (AUC 0.85), ≥ 75.8% fat-mass contribution to weight loss (AUC 0.85), postoperative waist circumference ≤ 107 cm (AUC 0.93), and waist-to-height ratio ≤ 0.72 (AUC 0.85). Logistic regression combining %TBWL and WHtR yielded an AUC of 1.00; however, this likely reflects overfitting given the very small remission subgroup.

CONCLUSION

Total weight loss and reductions in central adiposity were strongly associated with hyperglycemia remission after SG in women. Achieving 20–25% TBWL, ≥ 75% fat-mass contribution to weight loss, and postoperative waist circumference < 107 cm may represent candidate treatment targets, but require validation in larger independent cohorts.