Global 30-Day Morbidity and Mortality of Primary Bariatric Surgery Combined with Another Procedure: The BLEND Study

BLEND Study Collaborative Group

Research output: Contribution to journalArticlepeer-review


Background: No robust data are available on the safety of primary bariatric and metabolic surgery (BMS) alone compared to primary BMS combined with other procedures. Objectives: The objective of this study is to collect a 30-day mortality and morbidity of primary BMS combined with cholecystectomy, ventral hernia repair, or hiatal hernia repair. Setting: This is as an international, multicenter, prospective, and observational audit of patients undergoing primary BMS combined with one or more additional procedures. Methods: The audit took place from January 1 to June 30, 2022. A descriptive analysis was conducted. A propensity score matching analysis compared the BLEND study patients with those from the GENEVA cohort to obtain objective evaluation between combined procedures and primary BMS alone. Results: A total of 75 centers submitted data on 1036 patients. Sleeve gastrectomy was the most commonly primary BMS (N = 653, 63%), and hiatal hernia repair was the most commonly concomitant procedure (N = 447, 43.1%). RYGB accounted for the highest percentage (20.6%) of a 30-day morbidity, followed by SG (10.5%). More than one combined procedures had the highest morbidities among all combinations (17.1%). Out of overall 134 complications, 129 (96.2%) were Clavien-Dindo I–III, and 4 were CD V. Patients who underwent a primary bariatric surgery combined with another procedure had a pronounced increase in a 30-day complication rate compared with patients who underwent only BMS (12.7% vs. 7.1%). Conclusion: Combining BMS with another procedure increases the risk of complications, but most are minor and require no further treatment. Combined procedures with primary BMS is a viable option to consider in selected patients following multi-disciplinary discussion. Graphical Abstract: (Figure presented.)

Original languageEnglish
JournalObesity Surgery
Early online date13 Jun 2024
StateE-pub ahead of print - 13 Jun 2024
Externally publishedYes

Bibliographical note

Publisher Copyright:
© The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024.


  • Combined procedures
  • Concomitant cholecystectomy
  • Concomitant hiatal hernia repair
  • Concomitant ventral hernia repair
  • Primary bariatric and metabolic surgery


Dive into the research topics of 'Global 30-Day Morbidity and Mortality of Primary Bariatric Surgery Combined with Another Procedure: The BLEND Study'. Together they form a unique fingerprint.

Cite this