Banded Versus Non-banded Sleeve Gastrectomy: A Systematic Review and Meta-Analysis

Standard bariatric surgeries include biliopancreatic diversion (BPD), sleeve gastrectomy (SG), Roux-en-Y gastric bypass (RYGB), and adjustable gastric banding (AGB). Laparoscopic sleeve gastrectomy (LSG) is currently favored due to safety, efficacy, and shorter operation time. However, previous literature shows 75.6% weight regain post LSG. Introducing Laparoscopic band sleeve gastrectomy (LBSG) to maintain pouch size is proposed to improve outcomes and reduce weight regain. This study aims to compare the safety and efficacy of LSG vs. LBSG in obese patients. A comprehensive search strategy was executed to identify pertinent literature comparing LBSG and LSG in obese patients. Eligible studies underwent independent screening, and pertinent data were systematically extracted. The analysis employed pooled risk ratios (RR) for dichotomous outcomes and mean differences (MD) for continuous variables, each accompanied by their respective 95% confidence intervals (CI). Our systematic review and meta-analysis included 15 studies encompassing 3929 patients. Regarding body mass index (BMI), at six, 12, and 24 months, no substantial differences were found between LBSG and LSG groups (p < 0.05). Still, at 36 months, LBSG exhibited significantly lower BMI than LSG (MD = -2.07 [-3.84, -0.29], p = 0.02). Excess Weight Loss (EWL) favored LBSG at 12, 24, and 36 months with MD of 3.30 [0.42, 6.18], 4.13 [1.44, 6.81], and 18.43 [9.44, 27.42], p = 0.02, 0.003, < 0.00001, respectively). Operative time did not significantly differ between the procedures (MD = 2.95, 95%CI [-0.06, 5.95], p = 0.05). Resolution of comorbidities, overall complications, post-operative bleeding, reflux, and early complications did not significantly differ between LBSG and LSG. However, LBSG showed higher post-operative regurgitation than LSG (RR = 2.38, 95%CI [1.25, 4.54], p = 0.008). LBSG showed a substantial decrease in BMI at three-year follow-up and higher EWL at one, two, and three years. However, LBSG procedures exhibited a higher incidence of post-operative regurgitation symptoms than LSG. No substantial differences were noted in BMI at six, 12, or 24 months, EWL at six months, operative time, bleeding, reflux, or overall complications.


Introduction And Background
Obesity is a multifactorial disease that is linked to several comorbidities, mainly cardiovascular diseases and type 2 diabetes, and is associated with increased mortality rates [1].The obesity rate has dramatically increased in both sexes, across all ages, with the highest rate in the elderly and females [1].The exact mechanism of obesity remains controversial but is believed to be related to a complex interaction between factors such as regulation of energy balance, appetite, and physical activity besides hereditary and environmental factors [2].Adopting lifestyle changes continues to serve as the fundamental approach to addressing obesity, with consideration given to body mass index (BMI) thresholds.When BMI reaches or exceeds 30, pharmaceutical interventions can assist in achieving weight loss.However, individuals with a BMI surpassing 40 or those with a BMI exceeding 35, coupled with concurrent health conditions, are advised to consider bariatric surgery as the recommended course of action [3,4].
Standard bariatric surgeries are Biliopancreatic diversion (BPD), sleeve gastrectomy (SG), Roux-en-Y gastric bypass (RYGB), and adjustable gastric banding (AGB) [5].While the optimal procedure remains a subject of debate, the Laparoscopic sleeve gastrectomy (LSG) is currently the prevailing choice in practice [6].This preference stems from its established safety profile, efficacy, and notably shorter duration in the operating room [6].
Extended follow-up studies reveal a significant incidence of long-term weight regain, affecting approximately 75.6% of patients six years post LSG.This aspect notably constitutes a primary drawback of this procedure.Consequently, introducing a laparoscopic band sleeve gastrectomy (LBSG) to maintain the gastric pouch's size has been hypothesized as a means to enhance surgical outcomes and mitigate the postoperative weight regain, akin to the principles observed in banded RYGB [7,8].
Multiple clinical trials showed that the banded procedure has several benefits, including reduced food intake, delayed gastric emptying, altered hormonal levels, and esophageal peristalsis.Besides weight loss, less weight regain, reduction of reflux symptoms, and resolution of comorbidities [9,10].The superiority between banded and non-banded procedures remains a key inquiry in this field.Although a previous metaanalysis sought to address this query, its findings were constrained by several limitations, including limited incorporated randomized controlled trials (RCTs), small sample sizes, and insufficient follow-up durations.Thus, further investigations were warranted to provide more comprehensive insights into this matter [11].Our study aims to comprehensively compare the safety and efficacy of LSG vs. LBSG in obese patients.

Review Methods
This meta-analysis followed the preferred reporting item for systematic reviews and meta-analysis (PRISMA) guidelines and implemented the guidelines of the Cochrane Handbook for Systematic Reviews of Interventions [12,13].

Literature Search
We extensively searched various electronic databases, including Cochrane Library, PubMed, Scopus, Web of S.
cience, and EMBASE.Two reviewers independently searched Each database using the following research key terms: (Band OR Banded OR "Non-Banded" OR Banding OR "Silastic Band") AND (Gastrectom* OR "Stomach stapling" OR "Gastric sleeve surgery") AND (Bariatric OR Metabolic OR Obes*).This extensive search was conducted from inception till January 2024.Additionally, reference lists of eligible articles and previous meta-analyses were examined manually to identify relevant citations.

Eligibility Criteria
Two reviewers evaluated the retrieved studies independently and meticulously examined their eligibility according to our predetermined criteria: 1) We included studies on obese adults (>18 years old) with BMI > 35 kg/m 2 ).2) Studies comparing LBSG vs. LSG.3) Studies assessed any of the following outcomes for the mentioned interventions: BMI, EWL, operative time, reflux, regurgitation, or complications.
Numerous studies were excluded from analysis due to our exclusion criteria: 1) non-comparative studies, 2) studies not published in English, 3) editorial letters, abstracts, or comments only, and 4) incorporation of unpublished data.
Our primary outcome was to compare the improvement of anthropometric parameters after laparoscopic banded versus non-banded sleeve gastrectomy (BMI and percentage of Excess weight loss (EWL) after six, 12, 24, and 36 months of follow-up).The secondary outcomes were operative time, post-operative complications, bleeding, reflux, regurgitation, and resolution of comorbidities.

Data Gathering
data were extracted in offline data extraction sheets.Extracted data including various aspects such as the study ID, publication year, study location, study arms, sample size, gender distribution, participant ages, study inclusion criteria, conclusions, primary and secondary outcomes (anthropometric parameters, operative time, post-operative complications, bleeding, reflux, and regurgitation).Data in formats (such as median or range) were translated to mean ±SD using Cochrane Handbook Standard Deviation guidelines [10].

Risk of Bias Assessment
The quality assessment of the included trials was performed using the Cochrane Risk of Bias assessment tool 1 (ROB1) (designed for interventional studies) [14].It includes the following Items: random sequence generation, allocation concealment, blinding of investigators and participants, attrition bias, selective reporting, and other biases.Each domain was meticulously assessed to evaluate potential biases within the included studies comprehensively.The quality assessment of our included cohort studies was judged by the National Institutes of Health (NIH) tool [15].Also, we used MINORS Criteria for the assessment of nonrandomized clinical trials, which encompass the following seven domains: study aim, consecutive patient inclusion, prospective data collection, an appropriate endpoint to aim, evaluation of endpoint, follow-up period and percentage of loss of follow up [16].

Data Synthesis
We utilized different statistical methods based on outcome types: mean differences (MD) with standard deviations were pooled for continuous outcomes, while risk ratios (RR) with 95% confidence intervals were employed using the Mantel-Haenszel method for dichotomous outcomes.A fixed-effect model was initially 2024 Al-Juhani et al.Cureus 16(1): e52799.DOI 10.7759/cureus.52799used for homogeneous studies, but a random-effects model was applied for heterogeneous ones.Statistical heterogeneity was evaluated through I2 and Chi2 tests, with a p-value < 0.10 indicating heterogeneity and I2 ≥ 50% suggesting high heterogeneity.We used Review Manager (RevMan) version 5.4 to conduct all the analyses.

Characteristics of the Included Studies
We have fifteen included studies encompassing a total of 3929 patients.Regarding geographical distribution, seven were conducted in Egypt, four in Germany, two in Italy, and the remaining in India and Belgium.In our study, 3,122 patients were subjected to LSG procedure while only 807 LBSG, estimated BMI ranged from 45 to 53 kg/m 2 , with the majority of participants were hypertensive and diabetic.Patients' characteristics and a summary of the included studies are provided in Table 1.

Regurgitation
Four studies, including 421 patients [18,24,27,28], evaluated post-operative regurgitation; our analysis showed substantially higher regurgitation symptoms in the LBSG group when compared to the LSG our RR: 2.38 [1.25,4.54] and p-value=0.008.There was substantial heterogeneity among the pooled studies with 40%, 0.17. Figure 12 shows the forest plot for this outcome.

FIGURE 12: Forest plot of regurgitation incidence Discussion
Our systematic review and meta-analysis encompassed 15 studies, including 3,929 patients.After three years of follow-up, the banded group exhibited a significantly lower BMI (p-value <0.0001) and a notably higher percentage of EWL at multiple time intervals (one, two, and three years), with the most pronounced difference observed at the three-year (p-value <0.00001).Additionally, the LBSG group significantly reduced the incidence of post-operative regurgitation symptoms (p-value = 0.008) compared to the non-banded LSG group.However, we did not identify a substantial difference between the two groups regarding BMI after one year, %EWL after six months, operative time, post-operative bleeding, reflux, or overall complication.
The superiority of the banded procedure over traditional LSG stems from its potential to address a primary concern in LSG outcomes: post-operative weight regain, which remains a predominant cause of LSG failure and subsequent revisional surgeries.This weight regain often correlates with gastric pouch dilatation.Introducing a band around the gastric tube aims to mitigate this issue by preserving the size of the gastric pouch, thereby potentially reducing the incidence of post-operative weight regain, a critical factor contributing to improved long-term outcomes in banded procedures compared to traditional LSG [7].Previous literature revealed that inserting a nonadjustable gastric band improved weight loss outcomes in various bariatric operations [31][32][33][34][35].
The potential superiority of the banded procedure may be attributed to the band's impact on reducing appetite and activating peripheral satiety mechanisms.This effect involves slowing down the transmission of food within the longitudinal part of the sleeve, exerting minimal restriction.In contrast, LSG primarily operates through size reduction with minimal influence on satiety.Therefore, LBSG is hypothesized to enhance weight loss by combining both mechanisms, potentially amplifying weight loss outcomes without introducing additional complications [36,37].
Previous studies have posited that extended operative durations, particularly exceeding four hours, could potentially lead to prolonged hospital stays and an increased likelihood of post-operative complications.Moreover, prolonged operative times might negatively impact the recovery process of patients undergoing surgery [38][39][40][41].This aligned with our findings, indicating that banded LBSG exhibits a notably shorter operative time than traditional LSG.This disparity in duration might signify the relatively simpler technical approach associated with LBSG [6].In the literature, LSG was linked to aggravated preexisting regurgitation symptoms.This may be due to the anatomic and physiological changes caused by LSG [42,43].However, our study reported an increase in regurgitation with the LBSG group.
Chaouch et al.'s meta-analysis, encompassing 753 patients and comparing LBSG and LSG, concluded that banding in sleeve gastrectomy may result in a lower BMI and a higher %EWL after one year of follow-up.
Additionally, the study noted a significant reduction in %EWL after both one year and three years of followup in the banded group.However, the analysis found no substantial evidence supporting the superiority of LBSG over LSG in terms of mitigating vomiting, de novo gastroesophageal reflux disease (GERD), food intolerance, or reducing operative time [11].This aligned with our findings regarding BMI, %EWL, reflux, and operative time.Still, our evidence was more powered with a larger sample size and more robust stratifications according to follow-up periods.
Contrary to previous reflux findings, Alexander et al. presented a substantial reduction in symptoms following LBSG.Among 15 patients with preoperative reflux, eight experienced complete resolution of reflux symptoms, while the remaining patients observed symptomatic improvement.However, three patients developed mild reflux symptoms de novo after undergoing LBSG.Notably, none of the patients in their study necessitated reoperation for band removal due to reflux-related issues [44].In a systematic review conducted by Gehrer et al., the authors concluded that the data regarding the impact of LSG on GERD were inconclusive [45].Among the included studies, four demonstrated an elevated incidence of GERD postoperatively, while seven indicated a decrease in GERD following the procedure.However, it is important to note that all studies indicating a disparity in reflux symptoms between the studied procedures had a notably limited sample size or single-arm design, potentially impacting the robustness and generalizability of their findings.
Furthermore, previous literature supported our findings as follows.Lemmens et al., conducted over a fiveyear follow-up period, revealed a stark contrast in weight regain between LBSG and LSG groups [24].The findings showcased a significantly lower incidence of weight regain in the LBSG cohort, standing at 2%, in contrast to a substantially higher proportion of 19.6% observed in the LSG group.These results were further supported by evidence indicating that removal of the band led to subsequent weight gain, corroborating the pivotal role of banding in preventing weight regain following sleeve gastrectomy procedures [46].On the other hand, Tognoni et al. noted no statistically significant variances between the non-banded and banded groups during a 12-month follow-up.However, they observed slightly lower mean BMI values within the LBSG cohort than in the LSG group [29].Similarly, in a matched-cohort analysis encompassing 50 patients evenly distributed between both study arms, Karcz et al. did not discern statistically substantial distinctions in the percentage of estimated weight loss at the 12-month milestone between the two groups [25].
Parmar et al. reviewed six studies with 236 LBSG patients, finding a 77.4% mean weight loss at 12 months, 11.8% complications, 0.85% mortality, and 5.5% reoperations.However, they were limited by long-term data, which hindered definitive conclusions, prompting a call for more extensive studies for clearer insights [42].Gentileschi et al. randomized 50 patients into banded and non-banded LSG groups over four years, finding banded LSG yielded higher weight loss without added risks [9].
Although pros regarding LBSG were mentioned, there have been notable concerns surrounding the use of banding devices in bariatric surgery, primarily due to the potential risks associated with displacement, erosion, or slippage.These concerns have emerged based on previous data associated with using AGB.This procedure led to many patients requiring revision surgery to address complications stemming from the banding device [47].Unlike the AGB, the band used in LBSG is a relatively thin ring that remains loosely positioned without applying pressure on the sleeve.Importantly, its application involves minimal dissection on the lesser omentum, distinguishing it from the approach used in AGB procedures [9].
Currently, the number of cases involving banded LBSG remains relatively restricted, particularly when compared to the volume of other interventions within the field of bariatric surgery [18].Nonetheless, a meta-analysis encompassing over 8,000 patients who underwent banded Roux-en-Y gastric bypass (RYGB) with a decade-long follow-up revealed remarkably low complication rates (2.3% for erosion and 1.5% for slippage) [48].However, it is essential to note that this analysis was a single-arm study lacking comparability, potentially impacting its inferential statistical power.
Our study represents an updated evaluation of the comparative efficacy between banded and non-banded LSG, featuring a larger sample size and an extended follow-up duration of up to three years, allowing for a more comprehensive assessment of outcomes.However, it is important to emphasize the necessity for further extended follow-up periods to monitor the emergence of potential complications such as perforation, migration, or erosion.These complications may manifest over a longer duration post-surgery [49].
Still, our study was not free of limitations as follows.Firstly, including diverse study designs introduces potential heterogeneity, impacting the coherence and generalizability of our findings.Moreover, underpowered studies with small sample sizes might compromise our meta-analysis's statistical power and precision.Additionally, confounding factors in baseline characteristics, notably variations in BMI and other comorbidities across studies, could have influenced observed outcomes.Lastly, the largest study in our analysis featured unequal arms (LBSG vs. LSG) with a substantial ratio disparity (1:10), potentially introducing bias and impacting the comparative analysis [22].These limitations underscore the need for caution when interpreting our study's findings.The restricted sample sizes, potential for longer-term complications, and the complexity of outcomes like the resolution of comorbidities warrant careful consideration and moderation in drawing definitive conclusions from our results.

FIGURE 7 :
FIGURE 7: Forest plot of operative time (min)

FIGURE 10 :
FIGURE 10: Forest plot of post-operative bleeding