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. 2022 Aug;32(8):2556-2566.
doi: 10.1007/s11695-022-06128-3. Epub 2022 Jun 1.

Body Composition Differences Between Excess Weight Loss ≥ 50% and < 50% at 12 Months Following Bariatric Surgery

Jonathan Sivakumar  1   2 , Qianyu Chen  3 , Tom R Sutherland  4   5 , Matthew Read  3   6 , Salena Ward  3 , Lynn Chong  3 , Michael W Hii  3   6
Affiliations

Body Composition Differences Between Excess Weight Loss ≥ 50% and < 50% at 12 Months Following Bariatric Surgery

Jonathan Sivakumar et al. Obes Surg. 2022 Aug.

Abstract

Background: The relationship between weight loss and body composition is undefined after bariatric surgery. The objective of this study was to compare body composition changes in patients with excess weight loss ≥ 50% (EWL ≥ 50) and < 50% at 12 months post-operatively (EWL < 50).

Methods: A prospective cohort study was completed on patients undergoing bariatric surgery at two tertiary hospitals between 2017 and 2021. Body composition was measured with dual-energy X-ray absorptiometry immediately before surgery, and at 1, 6, and 12 months post-operatively. Body mass index (BMI), fat mass (FM), lean body mass (LBM), and skeletal muscle index (SMI) trajectories were analysed between patients with EWL ≥ 50% and EWL < 50%.

Results: Thirty-seven patients were included in this series (EWL ≥ 50% n = 25, EWL < 50% n = 12), comprising of both primary and revisional bariatric surgery cases, undergoing a sleeve gastrectomy (62.2%), Roux-en-Y gastric bypass (32.4%), or one anastomosis gastric bypass (5.4%). The EWL ≥ 50% group demonstrated a more optimal mean FM-to-LBM loss ratio than the EWL < 50% group. EWL ≥ 50% patients lost 2.0 kg more FM than EWL < 50% patients for each 1 kg of LBM lost. EWL ≥ 50% was also associated with an increase in mean SMI% over 12 months (5.5 vs. 2.4%; p < 0.0009). Across the whole cohort, the first month after surgery accounted for 67.4% of the total LBM reduction that occurred during the 12-month post-operative period.

Conclusion: This data suggests EWL ≥ 50% is associated with a more optimal body composition outcome than EWL < 50%. LBM reduction occurs predominantly in the early post-operative period.

Keywords: Bariatric surgery; Body composition; Weight loss.

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Conflict of interest statement

The authors declare no competing interests.

Figures

Fig. 1
Fig. 1
Process of patient selection for analysis
Fig. 2
Fig. 2
Linear prediction of changes in key anthropometry and body composition measurements at regular timepoints over 12 months post-operatively. EWL ≥ 50%, excess weight loss ≥ 50% at 12 months post-operatively; EWL < 50%, excess weight loss < 50% at 12 months post-operatively; BMI, body mass index; BMC, bone mineral content; SMI, skeletal muscle index
See this image and copyright information in PMC

References

    1. Buchwald H, Estok R, Fahrbach K, et al. Weight and type 2 diabetes after bariatric surgery: systematic review and meta-analysis. Am J Med. 2009;122(3):248–56.e5. doi: 10.1016/j.amjmed.2008.09.041. - DOI - PubMed
    1. Crémieux PY, Ledoux S, Clerici C, et al. The impact of bariatric surgery on comorbidities and medication use among obese patients. Obes Surg. 2010;20(7):861–870. doi: 10.1007/s11695-010-0163-6. - DOI - PubMed
    1. Grover BT, Morell MC, Kothari SN, et al. Defining weight loss after bariatric surgery: a call for standardization. Obes Surg. 2019;29(11):3493–9. doi: 10.1007/s11695-019-04022-z. - DOI - PubMed
    1. van de Laar AW, van Rijswijk AS, Kakar H, et al. Sensitivity and specificity of 50% excess weight loss (50%EWL) and twelve other bariatric criteria for weight loss success. Obes Surg. 2018;28(8):2297–2304. doi: 10.1007/s11695-018-3173-4. - DOI - PubMed
    1. Vázquez-Velázquez V, Rodríguez González A, Ordoñez Ortega S, et al. Differences in body composition in patients with obesity 1 year after Roux-En-Y gastric bypass: successful vs. unsuccessful weight loss. Obes Surg. 2018;28(3):864–8. - PubMed