Controlling Nutritional Status (CONUT) Score and Micronutrient Deficiency in Bariatric Patients: Midterm Outcomes of Roux-en-Y Gastric Bypass Versus One Anastomosis Gastric Bypass/Mini Gastric Bypass

Can AI Answer My Questions? Utilizing Artificial Intelligence in the Perioperative Assessment for Abdominoplasty Patients

BACKGROUND

Abdominoplasty is a common operation, used for a range of cosmetic and functional issues, often in the context of divarication of recti, significant weight loss, and after pregnancy. Despite this, patient-surgeon communication gaps can hinder informed decision-making. The integration of large language models (LLMs) in healthcare offers potential for enhancing patient information. This study evaluated the feasibility of using LLMs for answering perioperative queries.

METHODS

This study assessed the efficacy of four leading LLMs-OpenAI's ChatGPT-3.5, Anthropic's Claude, Google's Gemini, and Bing's CoPilot-using fifteen unique prompts. All outputs were evaluated using the Flesch-Kincaid, Flesch Reading Ease score, and Coleman-Liau index for readability assessment. The DISCERN score and a Likert scale were utilized to evaluate quality. Scores were assigned by two plastic surgical residents and then reviewed and discussed until a consensus was reached by five plastic surgeon specialists.

RESULTS

ChatGPT-3.5 required the highest level for comprehension, followed by Gemini, Claude, then CoPilot. Claude provided the most appropriate and actionable advice. In terms of patient-friendliness, CoPilot outperformed the rest, enhancing engagement and information comprehensiveness. ChatGPT-3.5 and Gemini offered adequate, though unremarkable, advice, employing more professional language. CoPilot uniquely included visual aids and was the only model to use hyperlinks, although they were not very helpful and acceptable, and it faced limitations in responding to certain queries.

CONCLUSION

ChatGPT-3.5, Gemini, Claude, and Bing's CoPilot showcased differences in readability and reliability. LLMs offer unique advantages for patient care but require careful selection. Future research should integrate LLM strengths and address weaknesses for optimal patient education.

LEVEL OF EVIDENCE V

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Changes in Nutritional Outcomes After Roux-en-Y Gastric Bypass: A Systematic Review and Meta-Analysis

BACKGROUND

Bariatric surgery (BS) is the most effective treatment for severe obesity and it has beneficial effects on glycemic control and metabolism outcomes. However, the effects of BS on nutritional outcomes are controversial. Therefore, we aimed to evaluate the changes in several nutritional outcomes after Roux-en-Y gastric bypass (RYGB).

METHODS

A comprehensive search was performed using the following databases: PubMed, Embase, Web of Science, Cochrane Library, WanFang and Chinese National Knowledge Infrastructure. The following outcomes were evaluated: vitamin A, 25-hydroxyvitamin D [25(OH)D], calcium, phosphorus, parathormone (PTH), iron, ferritin, vitamin B12, folate, and zinc. The pooled outcomes were expressed as standard mean difference (SMD) and 95% confidence interval (CI) using a random effects model.

RESULTS

Fifty-six studies including 5645 individuals with obesity met the inclusion criteria. Serum 25(OH)D (SMD = 0.78, 95%CI 0.38 to 1.20, P < 0.001), phosphorus (SMD = 0.48, 95%CI 0.22 to 0.74, P < 0.001), PTH (SMD = 0.35, 95%CI 0.11 to 0.59, P = 0.005), vitamin B12 (SMD = 1.11, 95%CI 0.41 to 1.80, P = 0.002), and folate (SMD = 1.53, 95%CI 0.77 to 2.28, P < 0.001) significantly increased after RYGB compared with the baseline. Serum ferritin (SMD =  - 1.67, 95%CI - 2.57 to - 0.77, P < 0.001), vitamin A (SMD =  - 0.64, 95%CI - 0.99 to - 0.29, P < 0.001), and plasma zinc (SMD =  - 0.58, 95%CI - 1.09 to - 0.06, P = 0.027) significantly decreased after RYGB. No significant changes in serum calcium (SMD =  - 0.14, 95%CI - 0.40 to 0.11, P = 0.219) and iron (SMD = 0.26, 95%CI - 0.11 to 0.64, P = 0.165) were observed after RYGB.

CONCLUSIONS

Despite the increased levels of 25(OH)D, phosphorus, vitamin B12 and folate, this meta-analysis revealed the unfavorable nutritional consequences after RYGB.

Evaluating Artificial Intelligence's Role in Teaching the Reporting and Interpretation of Computed Tomographic Angiography for Preoperative Planning of the Deep Inferior Epigastric Artery Perforator Flap

Background

Artificial intelligence (AI) has the potential to transform preoperative planning for breast reconstruction by enhancing the efficiency, accuracy, and reliability of radiology reporting through automatic interpretation and perforator identification. Large language models (LLMs) have recently advanced significantly in medicine. This study aimed to evaluate the proficiency of contemporary LLMs in interpreting computed tomography angiography (CTA) scans for deep inferior epigastric perforator (DIEP) flap preoperative planning.

Methods

Four prominent LLMs, ChatGPT-4, BARD, Perplexity, and BingAI, answered six questions on CTA scan reporting. A panel of expert plastic surgeons with extensive experience in breast reconstruction assessed the responses using a Likert scale. In contrast, the responses' readability was evaluated using the Flesch Reading Ease score, the Flesch-Kincaid Grade level, and the Coleman-Liau Index. The DISCERN score was utilized to determine the responses' suitability. Statistical significance was identified through a t-test, and P-values < 0.05 were considered significant.

Results

BingAI provided the most accurate and useful responses to prompts, followed by Perplexity, ChatGPT, and then BARD. BingAI had the greatest Flesh Reading Ease (34.7±5.5) and DISCERN (60.5±3.9) scores. Perplexity had higher Flesch-Kincaid Grade level (20.5±2.7) and Coleman-Liau Index (17.8±1.6) scores than other LLMs.

Conclusion

LLMs exhibit limitations in their capabilities of reporting CTA for preoperative planning of breast reconstruction, yet the rapid advancements in technology hint at a promising future. AI stands poised to enhance the education of CTA reporting and aid preoperative planning. In the future, AI technology could provide automatic CTA interpretation, enhancing the efficiency, accuracy, and reliability of CTA reports.

Micronutrient status 2 years after bariatric surgery: a prospective nutritional assessment

Background

Among commonly performed bariatric surgeries, biliopancreatic diversion with duodenal switch (BPD-DS) provides greater weight loss than Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG), with sustained metabolic improvements. However, the risk of long-term nutritional deficiencies due to the hypoabsorptive component of BPD-DS hinders its widespread use.

Objective

The aim of the study was to examine nutritional status over 2 years after BPD-DS, RYGB or SG.

Methods

Patients were recruited in the REMISSION trial (NCT02390973), a single-center, prospective study. Out of 215 patients, 73, 48 and 94, respectively, underwent BPD-DS, RYGB or SG. Weight loss, micronutrient serum levels (including iron, calcium, parathormone, vitamins A, B12 and D), and nutritional supplementation were assessed over 2 years. Patients were supplemented according to the type of surgery and individual micronutrient level evolution.

Results

At baseline, BPD-DS patients were younger than SG patients (p = 0.0051) and RYGB patients had lower body mass index (p < 0.001). Groups had similar micronutrient levels before surgery, with vitamin D insufficiency as the most prevalent nutritional problem (SG: 38.3%, RYGB: 39.9%, BPD-DS: 54.8%, p = 0.08). BPD-DS patients showed lower levels of iron, calcium and vitamin A than SG patients at 24 months. Groups had similar levels of vitamin D at 24 months. Prevalence of vitamin D, calcium, iron, vitamin A and vitamin B12 deficiency was similar among groups at 24 months. Rates of vitamin D insufficiency and iron deficiency were lower at 24 months than at baseline. Micronutrient intake was consistent with recommendations in groups post-surgery, but most BPD-DS patients took vitamin A and vitamin D supplement doses above initial recommendations.

Conclusion

With appropriate medical and nutritional management, all surgeries led to similar rates of vitamin D, calcium, iron, vitamin A and vitamin B12 deficiencies at 24 months. However, initial vitamin A and vitamin D supplementation recommendations for BPD-DS patients should be revised upwards.

Baseline 25(OH)D level is a prognostic indicator for bariatric surgery readmission: a matched retrospective cohort study

Introduction

Managing postsurgical complications is crucial in optimizing the outcomes of bariatric surgery, for which preoperative nutritional assessment is essential. In this study, we aimed to evaluate and validate the efficacy of vitamin D levels as an immunonutritional biomarker for bariatric surgery prognosis.

Methods

This matched retrospective cohort study included adult patients who underwent bariatric surgery at a tertiary medical center in China between July 2021 and June 2022. Patients with insufficient and sufficient 25(OH)D (< 30 ng/mL) were matched in a 1:1 ratio. Follow-up records of readmission at 3 months, 6 months, and 1 year were obtained to identify prognostic indicators.

Results

A matched cohort of 452 patients with a mean age of 37.14 ± 9.25 years and involving 69.47% females was enrolled. Among them, 94.25 and 5.75% underwent sleeve gastrectomy and gastric bypass, respectively. Overall, 25 patients (5.54%) were readmitted during the 1-year follow-up. The prognostic nutritional index and controlling nutritional status scores calculated from inflammatory factors did not efficiently detect malnourishment. A low 25(OH)D level (3.58 [95% CI, 1.16-11.03]) and surgery season in summer or autumn (2.68 [95% CI, 1.05-6.83]) increased the risk of 1-year readmission in both the training and validation cohorts. The area under the receiver operating characteristic curve was 0.747 (95% CI, 0.640-0.855), with a positive clinical benefit in the decision curve analyses. The relationship between 25(OH)D and 6-month readmission was U-shaped.

Conclusion

Serum 25(OH)D levels have prognostic significance in bariatric surgery readmission. Hence, preferable 25(OH)D levels are recommended for patients undergoing bariatric surgery.

Flowchart in Post-Bariatric Surgery: A Research for the Appropriate Type and Timing of Plasties Reshaping the Body

INTRODUCTION

Obesity is a chronic disease with significant health implications. Bariatric surgery is an effective treatment for obesity-related conditions. However, the timing of post-bariatric body contouring surgery remains uncertain.

MATERIALS AND METHODS

We conducted a retrospective study of 1336 patients who underwent bariatric surgery. We analyzed weight trends and variations after different types of bariatric procedures. The Pittsburgh Index was used to evaluate body contouring outcomes.

RESULTS

The majority of patients were women, and sleeve gastrectomy was the most common procedure. Weight loss varied depending on the surgery type, with different outcomes for male and female patients. The Pittsburgh Index remained stable in most cases.

CONCLUSION

Our findings suggest that the timing of body contouring surgery should be tailored to the type of bariatric procedure performed. Abdominoplasty is recommended as a last procedure for sleeve gastrectomy patients, while gastric bypass patients are suitable candidates for early abdominoplasty. Biliopancreatic diversion patients should stabilize their weight before abdominoplasty. The Pittsburgh Index is a valuable tool for assessing the timing of post-bariatric plastic surgery. Further research is needed to optimize surgical planning and outcomes.

LEVEL OF EVIDENCE V

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Impact of nutrition on skin wound healing and aesthetic outcomes: A comprehensive narrative review

Background

While current wound treatment strategies often focus on antimicrobials and topical agents, the role of nutrition in wound healing and aesthetic outcomes is crucial but frequently overlooked. This review assesses the impact of specific nutrients and preoperative nutritional status on surgical outcomes.

Methods

A comprehensive search was conducted in PubMed, Scopus, Web of Science, and the Cochrane Library, from the inception of the study to October 2023. The study focused on the influence of macronutrients and micronutrients on aesthetic outcomes, the optimization of preoperative nutritional status, and the association between nutritional status and postoperative complications. Inclusion criteria were English language peer-reviewed articles, systematic reviews, meta-analyses, and clinical trials related to the impact of nutrition on skin wound healing and aesthetic outcomes. Exclusion criteria included non-English publications, non-peer-reviewed articles, opinion pieces, and animal studies.

Results

Omega-3 fatty acids and specific amino acids were linked to enhanced wound-healing and immune function. Vitamins A, B, and C and zinc positively influenced healing stages, while vitamin E showed variable results. Polyphenolic compounds showed anti-inflammatory effects beneficial for recovery. Malnutrition was associated with increased postoperative complications and infections, whereas preoperative nutritional support correlated with reduced hospital stays and complications.

Conclusion

Personalized nutritional plans are essential in surgical care, particularly for enhanced recovery after surgery protocols. Despite the demonstrated benefits of certain nutrients, gaps in research, particularly regarding elements such as iron, necessitate further studies. Nutritional assessments and interventions are vital for optimal preoperative care, underscoring the need for more comprehensive guidelines and research in nutritional management for surgical patients.

The Effect of Drains and Compressive Garments Versus Progressive Tensioning Sutures on Seroma Formation in Abdominoplasty: A New Perspective for Abdominoplasty Procedure?

Authors comment on the paper "The effect of drains and compressive garments versus progressive tensioning sutures on seroma formation in abdominoplasty" written by Brown et al in Aesthetic Plastic Surgery.Although the authors present interesting results on the effectiveness of progressive tensioning sutures proposed originally by Pollok and Pollok, we express some considerations about the analyzed data and patients, hoping in a new research extending these findings to include both aesthetic and post-bariatric abdominoplasty patients, evaluating the effectiveness of these sutures in varied contexts.Level of Evidence V This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine Ratings, please refer to Table of Contents or online Instructions to Authors www.springer.com/00266 .

Letter on: "Platelet-Rich Plasma for Treatment of Hair Loss Improves Patient-Reported Quality of Life"

Authors comment on the paper "Platelet-Rich Plasma for Treatment of Hair Loss Improves Patient-Reported Quality of Life" written by Abigail Meyers et al in Aesthetic Plastic Surgery. Although the authors present interesting results on the quality of life of patients after platelet-rich plasma, we express some considerations about the proposed composition of PRP and hoping in larger sample study.Level of Evidence V This journal requires that authors assign a level of evidence to each article. For a full description of these evidence-based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Letter on "An Original Approach to Massive Weight Loss Deformities in the Lower Thigh: A Retrospective Assessment of Results and Patients"

Authors comment on the paper "An Original Approach to Massive Weight Loss Deformities in the Lower Thigh: A Retrospective Assessment of Results and Patients" written by Dr. Pierfranco Simone et al. Although the authors present excellent results on medial tight lift, we express some considerations about the proposed follow-up and hope in new research on this topic by Dr. Simone et al. using his interesting technique.Level of Evidence V This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Micronutrients Deficiencies in Candidates of Bariatric Surgery: Results from a Single Institution over a 1-Year Period

BACKGROUND

Micronutrient deficiencies represent a common condition after bariatric surgery (BS). The prevalence of these nutritional disorders before BS is still debated. The aim of our study was to retrospectively evaluate the prevalence of micronutrient deficiencies in candidates for BS.

METHODS

A prospectively maintained database of our institution was searched to find all patients who underwent surgery between January and December 2021. The following data were collected: age, gender, body mass index (BMI), obesity-associated diseases, and preoperative serum levels of vitamin B12, folate, and vitamin D.

RESULTS

A total of 174 patients were included in our study. Mean age and BMI were 39.2 ± 11.4 years and 44.3 ± 7.1 kg/m², respectively. One hundred and thirty-nine patients (79.9%) had at least one preoperative micronutrient disorder, with vitamin D deficiency being the most common (116, 66.7%), followed by a deficit of folate (76, 43.7%) and vitamin B12 (10, 5.7%). Forty-seven (27%) individuals had insufficient levels of vitamin D. Comparison of deficiencies between sexes showed that vitamin B12 < 20 ng/ml was significantly more frequent in women (p = 0.03). DLP showed a mild significant effect on folate levels (p = 0.01), while the association of HNT and T2DM had a mild significant effect on vitamin B12 (p = 0.02).

CONCLUSIONS

Preoperative micronutrient deficiencies were frequently found in candidates for BS. Approximately 90% of patients had deficient or insufficient serum levels of vitamin D preoperatively. Almost half of the patients had a preoperative deficit of folate, and vitamin B12 deficiency was significantly more frequent in the female population. It is mandatory to screen all patients undergoing BS for vitamin deficiencies before surgery.

Prognostic value of nutritional status in patients with human immunodeficiency virus infection-related lymphoma

Objective

To investigate the predictive value of nutritional status on the prognosis of patients with human immunodeficiency virus (HIV) infection-related lymphoma.

Materials and methods

A total of 149 patients with HIV infection-related lymphoma who were admitted to our hospital from August 2012 to May 2022 were selected as research subjects. Based on the patient prognosis, they were divided into a poor prognosis group (n = 30) and a good prognosis group (n = 119). General data from patients in both groups were collected, and the nutritional status of the patients was evaluated using the Controlling Nutritional Status (CONUT) score. Factors affecting the prognosis of HIV infection-related lymphoma were analyzed using univariate and multivariate analyses, and a prediction model was developed based on the analyzed factors. The receiver operating characteristic (ROC) curve was used to analyze the prediction model of the CONUT score alone and included the CONUT score in the prognosis of patients with HIV infection-related lymphoma. The predictive value of the data was assessed, and a survival curve was drawn to compare the survival of patients with different nutritional statuses.

Results

There were significant differences in age, B symptoms, treatment conditions, International Prognostic Index (IPI), pathological stage, Eastern Collaborative Tumor Group physical status score (ECOG PS), CD4+ cell count, β2 microglobulin, and lactate dehydrogenase (LDH) between the poor prognosis group and the good prognosis group (p &lt; 0.05). The CONUT score of the poor prognosis group was higher than that of the good prognosis group, and the difference was statistically significant (p &lt; 0.05). A univariate analysis demonstrated that the age, B symptoms, treatment status, IPI, pathological stage, ECOG PS, CD4+ cell count, β2 microglobulin, LDH, and CONUT score were prognostic factors for patients with HIV infection-related lymphoma (p &lt; 0.05). The results of a multivariate regression analysis demonstrated that the age, B symptoms, treatment status, IPI, pathological stage, ECOG PS, and CONUT score were independent risk factors for the prognosis of patients with HIV infection-related lymphoma (p &lt; 0.05). The prediction model was constructed according to the multivariate Cox regression analysis results. The model formula was as follows: Logit(p) = −10.687 + 1.728 × age + 1.713 × B symptoms + 1.682 × treatment status + 1.810 × IPI + 1.643 × pathological stage + 1.584 × ECOG PS + 1.779 × CONUT score. The ROC curve was used to analyze the predictive value of the CONUT score alone and the predictive model including the CONUT score on the prognosis of patients with HIV infection-related lymphoma. The predictive value of the prognosis of patients with tumors was higher (p &lt; 0.05). According to the results of the ROC curve analysis, the patients were divided into a high CONUT group (CONUT &gt; 6.00 points, n = 31) and a low CONUT group (CONUT ≤ 6.00 points, n = 118) based on the Optimum threshold of the CONUT score. The survival curve showed that the survival rate of the high CONUT group was lower than that of the low CONUT group (p &lt; 0.05).

Conclusion

The poor prognosis of HIV infection-related lymphoma is related to nutritional status, which is an independent risk factor affecting the prognosis of patients and can be used as a practical indicator to predict the prognosis of patients.

Nutritional Status after Roux-En-Y (Rygb) and One Anastomosis Gastric Bypass (Oagb) at 6-Month Follow-Up: A Comparative Study

Introduction: Roux-en-Y gastric bypass (RYGB) and one anastomosis gastric bypass (OAGB) are two effective bariatric surgical procedures with positive outcomes in terms of weight loss, comorbidities remission, and adverse events profiles. OAGB seems to carry a higher risk of malnutrition, but existing data are controversial. The aim of this study is to objectively evaluate and compare malnutrition in patients undergoing RYGB and OAGB. Methods: Retrospective monocentric study of obese patients undergoing RYGB or OAGB between the 15 September 2020 and the 31 May 2021. Nutritional status was assessed using the Controlling Nutritional Status (CONUT) score and compared between groups. The primary outcome was the mean CONUT score at 6 months. The secondary outcomes included the incidence of malnutrition, comorbidities, including hypertension, insulin resistance and type II diabetes mellitus, and weight loss. Results: 78 patients were included: 30 underwent RYGB and 48 underwent OAGB. At 6-Month Follow-Up there was no difference between groups in the mean CONUT score nor in incidence of malnutrition. In both groups, the nutritional status significantly worsened 6 months after surgery (preoperative and postoperative score of 0.48 ± 0.9 and 1.38 ± 1.5; p = 0.0066 for RYGB and of 0.86 ± 1.5 and 1.45 ± 1.3; p = 0.0422 for OAGB). Type II Diabetes mellitus (DMII) and hypertension remission were significant in the OAGB group with a 100% relative remission in the DMII-OAGB group (p = 0.0265), and a 67% relative remission in the hypertension-OAGB group (p = 0.0031). Conclusions: No difference in nutritional status has been detected between patients undergoing RYGB or OAGB at the 6-Month Follow-Up. Both procedures may have significant mal-absorptive effects leading to decline in nutritional status. OAGB may be more efficacious in inducing DMII and hypertension remission. Larger prospective studies dedicated specifically to nutritional status after gastric bypass are needed to confirm the impact of different bypass procedures on nutritional status.

Follow-up after bariatric surgery: is it time to tailor it? Analysis of early predictive factors of 3-year weight loss predictors of unsuccess in bariatric patients

Bariatric surgery (BS) is the most effective treatment strategy for obesity. Nevertheless, a subset of patients does not reach a successful weight loss or experience long-term weight regain. Conflicting evidence exists regarding predictors of BS outcomes. We aimed to define the early factors linked to 3 year unsuccessful weight loss in order to promote a tailored close follow-up. We enrolled 443 patients who underwent BS from January 2014 to December 2018 with a 3 year follow-up. An unsuccessful BS outcome was defined as a percentage of total weight loss (%TWL) < 20. We compared the characteristics between successful and unsuccessful patients in order to identify predictor factors of unsuccess after surgery. We found that the proportion of patients with unsuccessful weight loss progressively increased from one to three years after BS. In a multiple regression model, only 1 month %TWL and sleeve gastrectomy (SG) were significantly associated with 3 year unsuccessful weight loss. We stratified our cohort in four groups according to the risk of BS unsuccess, in terms of 1 month %TWL and type of surgery (SG vs gastric bypass). Interestingly, groups showed a significant difference in terms of %TWL at each follow-up point. Patients submitted to SG with lower 1 month %TWL must be considered at higher risk of future weight regain; consequently, they require a tailored and closer follow-up.

Generation and characterization of a mouse model for one anastomosis gastric bypass surgery

One anastomosis gastric bypass (OAGB) surgery became a common bariatric procedure in recent years. In this surgery, the distal stomach, duodenum, and proximal jejunum are bypassed, leading to weight loss, improvement in metabolic parameters, and a change in hormonal secretion. We sought to generate and characterize a mouse model for OAGB. Mice fed for 26 wk on a high-fat diet were assigned to OAGB, sham surgery, or caloric restriction and were followed for 50 more days on a high-fat diet. Physiological and histological parameters of the mice were compared during and at the end of the experiment. OAGB-operated mice lost weight and displayed low levels of plasma lipids, high insulin sensitivity, and rapid glucose metabolism compared with sham-operated mice. OAGB-operated mice had higher energy expenditure, higher levels of glucagon-like peptide (GLP-1), and lower albumin than weight-matched calorie-restricted mice. There was no difference in the histology of the endocrine pancreas. The livers of OAGB mice had little hepatic steatosis yet presented with a large number of phagocytic cells. The OAGB mouse model recapitulates many of the phenotypes described in patients that underwent OAGB and enables molecular and physiological studies on the outcome of this surgery.NEW & NOTEWORTHY A mouse model for one anastomosis gastric bypass (OAGB) surgery displays similar outcomes to clinical reports and enables to study the weight loss-dependent and -independent effects of this bariatric surgery.

Nutritional Complications After Laparoscopic Roux-en-Y Gastric Bypass and One-Anastomosis Gastric Bypass: A Comparative Systematic Review and Meta-Analysis

A systematic review and meta-analysis were carried out involving studies that compared the nutritional complications of Roux-en-Y gastric bypass (RYGB) and one-anastomosis gastric bypass (OAGB); these included the incidence of malnutrition as well as deficiencies of other nutritional elements, such as total protein, albumin, calcium and iron. A comprehensive search strategy was implemented in PubMed, Embase, and the Cochrane Library. Effect sizes included the pooled odds ratios (ORs) and 95% confidence intervals (95% CIs), as well as mean differences (MDs) and 95% CIs of the percentage total weight loss (%TWL) and excess weight loss percentage (%EWL).

Thirteen studies were included (12,964 patients, 66.27% females, 53.82% underwent OAGB). At the longest follow-up period (≥3 years), OAGB was associated with significantly higher %TWL (MD=5.41%, 95%CI, 1.52 to 9.29) and %EWL (MD=13.81%, 95%CI, 9.60 to 18.02) compared to RYGB. However, OAGB procedures were associated with malnutrition (OR=3.00, 95%CI, 1.68 to 5.36, p<0.0001), hypoalbuminemia (OR=2.38, 95%CI, 1.65 to 3.43, p<0.0001), hypoproteinemia (OR=1.85, 95%CI, 1.09 to 3.14, p=0.022), anemia (OR=1.38, 95%CI, 1.08 to 1.77, p=0.011), and hypocalcemia (OR=1.78, 95%CI, 1.01 to 3.12, p=0.046). On subgroup analyses, the proportions of anemia and hypoalbuminemia remained significantly higher at longer follow-up periods and in studies published in Asia.

Despite the favorable weight loss profile, the unfavorable nutritional consequences of OAGB merits further investigations to explore the malabsorptive element, ethnic variation, and the role of biliopancreatic limb length.