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What Is Weight Loss After Bariatric Surgery Expressed in Percentage Total Weight Loss (%TWL)? A Systematic Review

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Abstract

Percentage total weight loss (%TWL) might be better than percentage excess weight loss to express weight loss in bariatric surgery. In this systematic review, performed according to the PRISMA statement, results of laparoscopic sleeve gastrectomy (LSG) and Roux-en-Y gastric bypass (LRYGB) are assessed in %TWL. A total of 13,426 studies were screened and 49 included, reporting data of 24,760 patients. The results show that, despite limiting data, LRYGB is favorable over LSG in terms of weight loss in short-term follow-up. Although recent guidelines recommend to use %TWL when reporting outcome in bariatric surgery, this study shows that there is still insufficient quality data in %TWL, especially on LSG. The use of %TWL as the primary outcome measure in bariatric surgery should be encouraged.

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  1. Department of Surgery, Spaarne Gasthuis, Spaarnepoort 1, Hoofddorp, 2134 TM, the Netherlands

    Anne-Sophie van Rijswijk, Nienke van Olst & Arnold W. van de Laar

  2. Department of Scientific Information Service, The Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Plesmanlaan 121, Amsterdam, 1066 CX, the Netherlands

    Winnie Schats

  3. Department of Surgery, Amsterdam University Medical Center, location VU University, De Boelelaan 1117, Amsterdam, 1081 HV, the Netherlands

    Donald L. van der Peet

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  1. Anne-Sophie van Rijswijk
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van Rijswijk, AS., van Olst, N., Schats, W. et al. What Is Weight Loss After Bariatric Surgery Expressed in Percentage Total Weight Loss (%TWL)? A Systematic Review. OBES SURG 31, 3833–3847 (2021). https://doi.org/10.1007/s11695-021-05394-x

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