ASMBS updated position statement on insurance mandated preoperative weight loss requirements

The effect of preoperative body weight loss on 5-year bariatric surgery outcomes

OBJECTIVES

This study aimed to evaluate the effect of preoperative total body weight loss (TBWL) following a structured 6-month lifestyle change programme (LCP) on the level of TBWL at 12 months and its maintenance at 60 months post bariatric surgery (BS), as well as its impact on operation time, hospital stay, surgical complications and obesity-associated pathology remission.

METHODS

This retrospective, single-centre study analysed patients undergoing primary BS between 2013 and 2014. Outcomes were compared between patients participating in the LCP (LCP group) and those receiving standard preoperative education (Control group: CG). Data collected included anthropometric measurements, obesity-related pathologies, surgical complications, and weight-related outcomes.

RESULTS

Among 340 BS procedures performed, 165 patients met the inclusion criteria; 59 in the LCP group and 106 in the CG. The mean age was 47 ( ± 11.6) years in the LCP group and 45 ( ± 11.1) years in the CG with no significant differences in baseline clinical characteristics. At surgery, the LCP group showed significant weight reduction (-5.9 kg vs. -0.72 kg in controls, p = 0.008) and their BMI was significantly lower (46.55 vs. 49.47 kg/m², p = 0.002). Postoperatively, weight-related outcomes [BMI and TBWL] were better in the LCP group at 1 and 5 years. Additionally, patients achieving a preoperative TBWL > 5% demonstrated a significantly lower weight and BMI, along with a higher postoperative TBWL. Surgical complications were minimal, with no significant differences in 30-day complication rates. We did not observe a greater resolution of comorbidities in patients who participated in the LCP or those who achieved a preoperative TBWL ≥ 5%.

CONCLUSIONS

While current evidence suggests that preoperative TBWL provides short-term benefits, our data suggest this may also be the case for TBWL in the long-term. Further research is needed to fully elucidate the role of preoperative TBWL in comorbidity resolution in BS patients.

How Weight Bias and Stigma Undermine Healthcare Access and Utilization

PURPOSE OF REVIEW

To highlight recent evidence of the impact of weight bias and stigma on healthcare access and utilization.

RECENT FINDINGS

Healthcare access for patients with obesity is limited by weight-discriminatory policies such as body mass index cutoffs and weight loss requirements. These policies are based on flawed justifications without demonstrated medical benefits. Healthcare providers continue to hold negative views of patients with obesity, but recent evidence does not suggest that providers' weight-stigmatizing attitudes affect obesity treatment referrals. With the rise of new anti-obesity medications, more research is needed to understand how weight stigma may or may not affect providers' prescribing behavior and patients' access to this form of treatment. Experienced, anticipated, and internalized weight stigma is associated with patients' avoidance of healthcare and reduced utilization. Weight bias and stigma limit healthcare access and utilization. Structural changes are needed to remove weight-discriminatory barriers to care.

Beyond race: social vulnerability and access to metabolic and bariatric surgery

BACKGROUND

Metabolic and bariatric surgery (MBS) is under-accessed by non-White patients, who are disproportionately affected by obesity. We hypothesized that unique barriers experienced by socially vulnerable patients drive disparate MBS utilization.

OBJECTIVES

To determine whether socially vulnerable patients experience greater attrition and face more insurance-mandated medical weight management (MWM) requirements.

SETTING

Urban, academic center.

METHODS

This retrospective cohort study included adults evaluated for MBS in 2018. Social vulnerability was determined using the 2018 Social Vulnerability Index. Outcomes included attrition, or failure to undergo surgery within 1year, and the number and duration of MWM requirements. Multivariable logistic regression and negative binomial regression tested these associations.

RESULTS

In 2018, 339 patients were evaluated for MBS (83% female, 70% Black). The attrition rate was 57%. On adjusted analyses, patients in the highest social vulnerability quartile had double the odds of attrition compared to their least vulnerable counterparts (OR 2.33, 95% CI 1.11-4.92, P = .03). Highly vulnerable patients had double the number (IRR 2.29, 95% CI 1.42-3.72, P = .001) and nearly quadruple the duration (IRR 3.90, 95% CI 1.93-7.86, P < .001) of MWM requirements compared to those with low social vulnerability. Odds of attrition increased by 11% and 20% for each additional MWM visit (OR 1.11, 95% CI 1.02-1.20, P = .02) and month (OR 1.20, 95% CI 1.08-1.33, P = .001), respectively.

CONCLUSIONS

Patients with high social vulnerability were less likely to undergo MBS and faced more insurance-mandated preoperative requirements, which independently predicted attrition. Insurance-mandated MWM is inequitable and may contribute to disparate care of patients with severe obesity.

Impact of Preoperative Weight Loss on 30-Day Complication Rate after Bariatric Surgery

BACKGROUND

The aim of this study is to evaluate the impact of preoperative weight loss on surgical outcomes and operating room (OR) times after primary bariatric procedures, including laparoscopic sleeve gastrectomy (LSG) and laparoscopic Roux-en-Y gastric bypass (RYGB).

STUDY DESIGN

A retrospective cohort study uses the 2021 MBSAQIP dataset. Preoperative total weight loss (TWL)% was calculated. Patients were then divided in to 4 groups: those with no weight loss, lost <0 to <5%, lost ≥5% to <10%, or lost ≥10% TWL preoperatively. These groups were then stratified into those with BMI less than 50 kg/m 2 and those with BMI 50 kg/m 2 or more and 30-day outcomes and OR times were compared.

RESULTS

Analysis included 171,010 patients. For BMI less than 50 kg/m 2 , preoperative weight loss led to no consistent improvement in surgical outcomes. Although >0% to <5% TWL led to a decrease in intra- and postoperative occurrences after RYGB and a decrease in reoperation rates after LSG, these observations were not seen in those with higher degree of weight loss. In patients with BMI 50 kg/m 2 or more, preoperative weight loss showed a consistent improvement in reintervention rates after LSG, and readmission rates after RYGB. There was no improvement in other outcomes, however, irrespective of degree of preoperative weight loss.

CONCLUSIONS

In patients undergoing primary bariatric surgery, preoperative weight loss does not lead to a consistent improvement in outcomes or OR times. In those with BMI 50 kg/m 2 or more, there may be improvement in select outcomes that is procedure-specific. Overall, these data do not support a uniform policy of preoperative weight loss, although selective use in some high-risk patients may be appropriate.

The impact of gender, race, and ethnicity on bariatric surgery outcomes

BACKGROUND

The rates of postoperative complications can vary among specific patient populations.

OBJECTIVES

The aim of this study is to examine how gender, race, and ethnicity can affect short-term postoperative complications in bariatric surgery patients.

SETTING

United States.

METHODS

Patients who underwent bariatric surgery between the years 2016 and 2021 were included and stratified based on gender, race/ethnicity, and procedure type. The 30-day outcomes were assessed using Clavien-Dindo (CD) classification of III-V. Wilcoxon rank-sum test was performed to compare continuous variables among groups and Chi-squared test for categorical variables. Logistic regression was performed to examine the effects of gender, race/ethnicity on CD classification ≥ III complications by the procedure type.

RESULTS

A total of 975,642 bariatric surgery patients were included. Descriptive univariate analysis showed that CD ≥ III complications were higher among non-Hispanic blacks (NHB) and lowest in Hispanic patients, regardless of their gender, except in the duodenal switch DS group, where non-Hispanic whites (NHW) had the lowest complication rate. There was no difference between male and female patients with regards to postoperative complications, except in the sleeve gastrectomy (SG) group, where NHW males had more complications than NHW females. Sleeve gastrectomy showed the lowest complication rates followed by gastric bypass and DS in all groups. In multivariate logistic regression model, for both females and males NHBs had higher odds of postoperative complications compared to NHWs in sleeve gastrectomy (Female aOR:1.31, 95% CI: [1.23-1.40]; Male aOR:1.24, 95% CI: [1.08-1.43], P < .001) and gastric bypass (Female aOR:1.24, 95% CI: [1.16-1.33]; Male aOR:1.25, 95% CI: [1.06-1.48], P < .01).

CONCLUSIONS

Non-Hispanic Black patients are at a higher rate of developing CD ≥ III complications compared to non-Hispanic Whites after bariatric surgery. The male gender was not a significant risk factor for serious postoperative complications. Among the different types of bariatric procedures, sleeve gastrectomy has the lowest rates of severe complications, followed by gastric bypass and duodenal switch. These results highlight the significance of considering gender, race, ethnicity, and procedure type during preoperative evaluation, surgical planning, and postoperative care.

Addressing uncertainty about the role of structured lifestyle modification for metabolic surgery patients

There is good evidence that structured lifestyle modification programmes improve health in patients with metabolic and cardiovascular disorders, but there is no specific evidence that they improve outcomes in patients undergoing metabolic or obesity surgery. Despite expert consensus guidelines stating this fact, some healthcare systems still compel patients to participate in a structured lifestyle modification programme prior to metabolic or obesity surgery. There is a well-established need for individualised multidisciplinary dietetic and physical activity care for metabolic and obesity surgery patients, and the benefits of intentional weight loss prior to surgery are well proven, but these are distinct from potentially harmful requirements for patients to undertake compulsory structured lifestyle programmes of fixed duration, frequency and intensity, which may delay surgery and reinforce obesity stigma. A critical step in rejuvenating metabolic surgery is to reframe patient participation in structured lifestyle modification programmes as an opportunity for education and empowerment, not as an indicator of motivation or suitability for metabolic surgery. Large, well-designed and adequately powered clinical trials are needed to address uncertainties in the evidence base for these programmes. Given genuine equipoise, they will need to determine whether "surgery plus lifestyle" is superior to "surgery plus placebo". Moreover, they will need to determine the cost-effectiveness of these programmes and identify some of the factors giving rise to the substantial heterogeneity in responses to structured lifestyle modification.

Evaluate the Effects of Different Types of Preoperative Restricted Calorie Diets on Weight, Body Mass Index, Operation Time and Hospital Stay in Patients Undergoing Bariatric Surgery: a Systematic Review and Meta Analysis Study

Previous studies investigated low-calorie diets (LCD), very-low-calorie diets (VLCD), and very-low-calorie ketogenic diets (VLCKD) in relation to weight loss and outcomes for bariatric surgery patients. However, the overall effects of these diets on various outcomes remain unclear. This study aimed to assess the impact of preoperative restricted calorie diets on weight, body mass index (BMI), operation time (OT), and hospital stay (HS) in bariatric surgery patients. Seventeen articles were analyzed, revealing the highest weight loss (-8.62) and BMI reduction (-5.75) with VLCKD. Due to insufficient data, the impact of these diets on OT and HS could not be determined. Further interventional studies are required to determine the ideal preoperative diet that achieves optimal weight loss, patient compliance, tolerance, acceptance, and surgical outcomes.

Preoperative Weight Gain Is Not Related to Lower Postoperative Weight Loss, But to Lower Total Weight Loss up to 3 Years After Bariatric-Metabolic Surgery

INTRODUCTION

Weight loss prior to bariatric-metabolic surgery (BMS) is recommended in most bariatric centers. However, there is limited high-quality evidence to support mandatory preoperative weight loss. In this study, we will evaluate whether weight gain prior to primary BMS is related to lower postoperative weight loss.

METHODS

A retrospective analysis of prospectively collected data was performed. Preoperative weight loss (weight loss from start of program to day of surgery), postoperative weight loss (weight loss from day of surgery to follow-up), and total weight loss (weight loss from start of program to follow-up) were calculated. Five groups were defined based on patients' preoperative weight change: preoperative weight loss of >5 kg (group I), 3-5 kg (group II), 1-3 kg (group III), preoperative stable weight (group IV), and preoperative weight gain >1 kg (group V). Linear mixed models were used to compare the postoperative weight loss between group V and the other four groups (I-IV).

RESULTS

A total of 1928 patients were included. Mean age was 44 years, 78.6% were female, and preoperative BMI was 43.7 kg/m2. Analysis showed significantly higher postoperative weight loss in group V, compared to all other groups at 12, 24, and 36 months follow-up. Up to three years follow-up, highest total weight loss was observed in group I.

CONCLUSION

Weight gain before surgery should not be a reason to withhold a bariatric-metabolic operation. However, patients with higher preoperative weight loss have higher total weight loss. Therefore, preoperative weight loss should be encouraged prior to bariatric surgery.

The involvement of circulating CD69+ CD56bright natural killer cells in weight loss before bariatric surgery: A retrospective cohort study

As the impact of the immune system on weight loss prior to bariatric surgery has never been proven, we elucidated the clinical utility of the immune system as an indicator of preoperative weight loss before bariatric surgery. We examined the relationships between preoperative weight loss and biochemical and clinical data at the initial visit in 34 obese patients. Patients were divided according to preoperative weight loss, and peripheral blood mononuclear cells were compared using flowcytometry. The Δpreoperative excess weight loss [Δpre-EWL: pre-EWL (%)/period of preoperative weight loss (days)] showed negative correlations with total and subcutaneous fat area (P = .02, r = -0.41, P = .02, r = -0.42 respectively). The Δpre-EWL and Δpreoperative total weight loss (Δpre-TWL) were negatively correlated with white blood cell count, lymphocyte count, and C-reactive protein (CRP) levels at the initial visit (Δpre-EWL; P = .02, r = -0.37, P = .01, r = -0.41, P = .008, r = -0.45, Δpre-TWL; P = .01, r = -0.40, P = .01, r = -0.42, P = .01, r = -0.42, respectively). Multivariate regression modeling showed that both Δpre-EWL and Δpre-TWL were significantly associated with lymphocyte count (Δpre-EWL; P = .01, Δpre-TWL; P = .01). A comparison between the high (Δ pre-EWL > 0.098) and low weight loss group (Δ pre-EWL < 0.098) demonstrated a significant difference in the expression of the activation marker CD69 on CD56bright Natural killer (NK) cells (P = .01), whereas there was no difference in the frequency of T cells, Natural killer T cells, or NK cells. Additionally, high CRP levels were associated with CD69 expression in CD56bright NK cells (P = .01, R = 0.57). Peripheral lymphocytes, especially CD69-positive CD56bright NK cells, are involved in preoperative weight loss after bariatric surgery, and systemic inflammation may inhibit weight loss before surgery.

Impact of Treatment with GLP1 Receptor Agonists, Liraglutide 3.0 mg and Semaglutide 1.0 mg, While on a Waiting List for Bariatric Surgery

BACKGROUND

Weight loss before undergoing metabolic and bariatric surgery (MBS) has been suggested to reduce perioperative complications, although with controversial results. The objective of this study is to evaluate the impact of treatment with GLP1-R agonists (liraglutide 3.0 mg and semaglutide 1.0 mg) on preoperative weight loss and patients' decisions regarding MBS while on a surgical waiting list.

MATERIALS AND METHODS

One hundred and two patients on a waiting list for MBS started treatment with GLP1-RA for at least 6 months. Changes in weight at 26 and 52 weeks, the number of patients achieving >5% weight loss, and patients' decisions regarding MBS were evaluated.

RESULTS

After 52 weeks, patients lost 16.9 ± 7.2% of weight with semaglutide 1.0 mg and 16.1 ± 5.8% of weight with liraglutide 3.0 mg. All patients lost ≥5% of initial weight, 84.7% lost ≥10%, 54.6% lost ≥15%, and 27.5% reached ≥20%. A total of 68.6% of participants were satisfied with the achieved weight loss and withdrew from the waiting list for MBS. A threshold of >15.1% weight loss had the greatest sensitivity and specificity for the final decision regarding undergoing MBS.

CONCLUSIONS

Losing >15% of initial weight after 52 weeks of treatment with liraglutide 3.0 mg or semaglutide 1.0 mg during the waiting list for MBS impacts patients' decisions regarding the final acceptance or rejection of the procedure.

Barriers to Bariatric Surgery: a Mixed Methods Study Investigating Obstacles Between Clinic Contact and Surgery

PURPOSE

Populations most affected by obesity are not reflected in the patients who undergo bariatric surgery. Gaps in the referral system have been studied, but there is a lack of literature investigating obstacles patients encounter after first contact with bariatric surgery clinics. We aim to identify patient populations at risk for attrition during bariatric surgery evaluation and determine patient reported barriers to bariatric surgical care.

MATERIALS AND METHODS

This study was a single institution, retrospective, mixed methods study from 2012 to 2021 comparing patients who underwent bariatric surgery to those that withdrew. Surveys were performed of patients who withdrew, collecting information on patient knowledge, expectations, and barriers.

RESULTS

This study included 5982 patients evaluated in bariatric surgery clinic. Those who attained bariatric surgery (38.8%) were more likely to be White (81.2 vs. 75.6%, p<0.001), married (48.5 vs. 44.1%, p=0.004), and employed full time (48.2 vs. 43.8%, p=0.01). They were less likely to live in an area with low income (37.1 vs. 40.7%, p=0.01) or poverty (poverty rate 15.8 vs. 17.4, p<0.001). Of the 280 survey respondents, fear of complications, length of insurance approval process, and wait time between evaluation and surgery were the most reported barriers.

CONCLUSION

Patients who undergo bariatric surgery were more likely to be White, married, employed full time, and reside in more resourced environments which is not reflective of communities most affected by obesity. The complexity of insurance coverage requirements was a major barrier to bariatric surgery and should be a focus of future healthcare reform.

Insurance-mandated weight management program completion before bariatric surgery provides no long-term clinical benefit

BACKGROUND

There is no evidence that insurance-mandated weight loss before bariatric surgery affects outcomes.

OBJECTIVE

This retrospective study evaluated the relationship between insurance-mandated weight management program (WMP) completion before primary bariatric surgery and postoperative outcomes.

SETTING

Suburban academic medical center.

METHODS

Patients who underwent laparoscopic Roux-en-Y gastric bypass (LRYGB, n = 572) or sleeve gastrectomy (SG, n = 484) from 2014 to 2019 were dichotomized to presence (LRYGB n = 431, SG n = 348) or absence (LRYGB n = 141, SG n = 136) of insurance-mandated WMP completion. Primary endpoints included follow-up rate, percent total weight loss (%TWL), and percent excess weight loss (%EWL) through 60 months after surgery. The Mann-Whitney U test compared between-group means with significance at P < .05.

RESULTS

Follow-up rate, %TWL, and %EWL were not different (P = NS) up to 60 months postoperation between groups for either surgery. Both LRYGB and SG patients without WMP completion maintained greater %TWL (LRYGB: 34.4 ± 11.1% versus 29.8 ± 11.0%, P = .159; SG: 21.4 ± 10.0% versus 18.2 ± 10.5%, P = .456) and %EWL (LRYGB: 71.3 ± 26.3% versus 67.6 ± 26.5%, P = .618; SG: 49.2 ± 18.8% versus 47.5 ± 28.8%, P = .753) at 36 months after surgery. Secondarily, duration of time to get to surgery was significantly greater among yes-WMP patients (LRYGB: 178 days versus 121 days, P < .001; SG: 169 days versus 95 days, P < .001).

CONCLUSION

Insurance-mandated WMP completion before bariatric surgery delays patient access to surgery without improving postoperative weight loss potential and must be abandoned.

Preoperative Weight Loss as a Predictor of Short and Midterm Postoperative Weight Loss in Patients Undergoing Bariatric Surgery

Objective

To examine if preoperative weight loss correlates to postoperative weight loss 2 and 3 years after surgery.

Methods

A review was conducted of bariatric surgery patients who underwent either gastric bypass or sleeve gastrectomy during 2015-2018 and had 3-year follow-up data. Demographic and outcome data were collected. A best-fit regression model for weight loss was constructed.

Results

Eight hundred fifty-nine patients underwent surgery during the selected period, of which 199 patients (23%) were analyzed. Eighty-two percent of patients had gastric bypass and 82% were female. Preoperative percent excess weight loss (%EWL) was not significantly associated with 2- and 3-year postoperative %EWL (p = 0.18). Patients demonstrated significant weight regain at 3 years postoperatively versus 1 year (p < 0.01). Higher preoperative weight loss was associated with lower %EWL 3 years postoperatively versus 1 year (p = 0.04). Postoperative %EWL had a significant negative association with higher preoperative weight, diabetes, baseline use of a mobility device, and sleeve gastrectomy.

Conclusions

In a cohort of bariatric surgery patients, there was no statistically significant association between preoperative and midterm postoperative %EWL. Postoperative %EWL was negatively associated with several patient-specific factors and increasing time since operation.

Variation and outcomes of liver-reducing dietary regimens before bariatric surgery: a national retrospective cohort study

BACKGROUND

Liver-reducing diets (LRDs) are mandated prior to bariatric surgery, but there are no guidelines on their implementation.

OBJECTIVE

To establish the variation and effectiveness of LRDs utilized in clinical practice.

SETTING

A nationwide, multicenter, retrospective cohort study.

METHODS

A total of 1699 adult patients across 14 bariatric centers in the United Kingdom were included. Multilevel logistic regression models were developed to examine factors predictive of 5% weight loss.

RESULTS

Most centers (n = 9) prescribed an 800- to 1000-kcal diet, but the duration and formulation of diet was variable. Overall, 30.6% (n = 510) of patients achieved 5% weight loss during the LRD. After adjustment for preoperative weight, women had reduced odds (odds ratio [OR], .65; 95% confidence interval [CI], .48-.88; P = .005), while increasing age (OR, 1.01; 95% CI, 1.00-1.02; P = .043) and having type 2 diabetes (OR, 1.49; 95% CI, 1.16-1.92; P = .002) increased odds of 5% weight loss. A normal consistency food LRD (OR, .64; 95% CI, .42-.98; P = .041) and energy prescription of >1200 kcals/d (OR, .33; 95% CI, .13-.83; P = .019) reduced odds, while an LRD with a duration of 3 weeks (OR, 2.28; 95% CI, 1.02-5.09; P = .044) or greater increased odds of 5% weight loss.

CONCLUSIONS

There is wide variation in how LRDs are delivered in clinical practice, highlighting the need for an evidence-based consensus. Our findings suggest the optimal LRD before bariatric surgery contains 800 to 1200 kcals/d over a duration of 3 to 4 weeks. Further research is required to determine the optimal formulation of LRD and whether women may require a lower-energy LRD than men.

Reasons for Preoperative Patient Attrition among Bariatric Surgery Candidates: Patients' Point of View

PURPOSE

Obesity has become a global health concern, associated with decreased quality of life and life expectancy. Although bariatric surgery has many benefits (e.g., substantial and durable weight loss, amelioration of comorbidities, and improvement in functionality), its patient attrition rate is relatively high. Therefore, we aim to assess the causes of withdrawal from our program.

MATERIALS AND METHODS

We interviewed patients who dropped out of our bariatric surgery program between January 2016 and December 2021. A total of 1999 patients were eligible for bariatric surgery during this period, and 255 patients withdrew from the program. We interviewed patients over the phone to find out the reason for withdrawal. We divided participants into two groups: dropouts before and during the COVID-19 pandemic. Several options explaining the reason for leaving the program were presented to the patients to choose from.

RESULTS

The number of patients who withdrew from the program before and during the COVID-19 pandemic was 135 (8.9%) and 120 (25.2%), respectively. Before the COVID-19 pandemic, most patients (49.1%) stated that the long waiting time was the cause of withdrawal. Even though during the COVID-19 pandemic, the main causes of attrition were the fear of contracting the disease and COVID-19 infection; the most common reason unrelated to COVID-19 was still the long preoperative preparation.

CONCLUSION

Long waiting time was the most common cause of patient attrition before bariatric surgery. To reduce the attrition rate, more studies should be conducted to find an optimized waiting time before bariatric surgery.

2022 American Society of Metabolic and Bariatric Surgery (ASMBS) and International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO) Indications for Metabolic and Bariatric Surgery

MAJOR UPDATES TO 1991 NATIONAL INSTITUTES OF HEALTH GUIDELINES FOR BARIATRIC SURGERY: Metabolic and bariatric surgery (MBS) is recommended for individuals with a body mass index (BMI) >35 kg/m2, regardless of presence, absence, or severity of co-morbidities.MBS should be considered for individuals with metabolic disease and BMI of 30-34.9 kg/m2.BMI thresholds should be adjusted in the Asian population such that a BMI >25 kg/m2 suggests clinical obesity, and individuals with BMI >27.5 kg/m2 should be offered MBS.Long-term results of MBS consistently demonstrate safety and efficacy.Appropriately selected children and adolescents should be considered for MBS.(Surg Obes Relat Dis 2022; https://doi.org/10.1016/j.soard.2022.08.013 ) © 2022 American Society for Metabolic and Bariatric Surgery. All rights reserved.

2022 American Society for Metabolic and Bariatric Surgery (ASMBS) and International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO): Indications for Metabolic and Bariatric Surgery

Major updates to 1991 National Institutes of Health guidelines for bariatric surgery.

Literature review on antiobesity medication use for metabolic and bariatric surgery patients from the American Society for Metabolic and Bariatric Surgery Clinical Issues Committee

The following literature search is in response to inquiries made to the American Society for Metabolic and Bariatric Surgery (ASMBS) regarding antiobesity medication (AOM) use in patients who are having or have already had metabolic and bariatric surgery (MBS). These recommendations are based on current clinical knowledge, expert opinion, and published peer-reviewed scientific evidence available at this time. This paper is not intended to establish a local, regional, or national standard of care. The paper will be revised in the future as additional evidence becomes available.

Ketogenic Diet for Preoperative Weight Reduction in Bariatric Surgery: A Narrative Review

Bariatric surgery (BS) is the most effective treatment in reducing weight and the burden of comorbidities in patients with severe obesity. Despite the overall low mortality rate, intra- and post-operative complications remains quite common. Weight loss before BS reduces surgical risk, but studies are inconclusive regarding which is the best approach to apply. In this review, we summarize the current evidence on the effect of a ketogenic diet (KD) before BS. All studies agree that KD leads to considerable weight loss and important improvements in terms of surgical risk, but populations, interventions and outcomes are very heterogeneous. KD appears to be a safe and effective approach to induce weight loss before BS. However, randomized controlled trials with better-defined dietary protocols and homogeneous outcomes are necessary in order to draw firm conclusions.

Nutritional Management and Role of Multidisciplinary Follow-Up after Endoscopic Bariatric Treatment for Obesity

The prevalence of obesity has risen exponentially, and patients living with obesity suffer from its debilitating consequences. The treatment options for obesity have expanded significantly and include lifestyle changes, pharmacotherapy, endoscopic bariatric therapies (EBTs), and bariatric surgery. Endoscopic bariatric therapies comprise volume-reducing procedures such as endoscopic gastroplasty and gastric space-occupying devices such as intragastric balloons. Because of its minimally invasive nature and ease of delivery, EBTs are increasingly being adopted as a treatment option for obesity in several centers. These procedures mainly achieve weight loss by inducing early satiety and reducing meal volume. While the technical aspects of EBTs have been well explained, the nutritional management surrounding EBTs and the effectiveness of multidisciplinary team for maximizing weight loss is less described. There is considerable variation in post-EBT care between studies and centers. In this paper, we review the existing literature and share our experience on nutrition and the role of multidisciplinary management of obesity following EBT.

The avoidable delay in weight loss surgery for those with BMI over 50

BACKGROUND

Many insurance companies mandate medically supervised weight loss programs (MSWLPs) prior to bariatric surgery. This retrospective study aims to elucidate whether the average 6-month preoperative medical-management period decreases preoperative BMI for those with BMI ≥ 50.

METHODS

All adult patients with bariatric consultation at any time at the New York University Langone Health campuses during the period 2015 to 2021 were evaluated via electronic medical records. Only patients with ≥ BMI 50, without previous bariatric surgeries, and those with 6-month insurance-mandated medical visits were included. A paired t-test was performed on the difference in BMI and percent-weight loss among the subjects at least 6 months before surgery and on the day of surgery.

RESULTS

Of the 130 patients with BMI ≥ 50, undergoing preoperative 6-month office weigh-ins, the mean difference in BMI was - 1.51 (P < 0.01). The mean total body weight loss was 4.8% (P < 0.01). There were no intraoperative complications nor 30-day complications or mortality in the group.

CONCLUSIONS

We found that there was weight loss during the 6-month insurance-mandated medical management prior to surgery, but the amount (4.8%) did not reach the goal target of 10% of body weight. We found that there were no complications and question the need for prolonged delay to surgery.

The relationship between preoperative weight loss and intra and post-bariatric surgery complications: an appraisal of the current preoperative nutritional strategies

Preoperative weight loss before a bariatric surgery reduces long-term complications, but there is no solid evidence for short-term or perioperative complications. This review highlights recent evidence on dietary protocols and the possible correlation between weight loss and surgical complications. Updated evidence was searched in PubMedDirect with the terms "preoperative very low-calorie diet or very-low-calorie ketogenic diet or low-fat diet or intermittent fasting or Mediterranean diet and bariatric surgery or bariatric surgery complications." The main characteristics of each diet, achievements related to weight loss, liver reduction, peri and postoperative outcomes, surgical complications, tolerance, and adherence to the diet are presented from the selected studies. There are few reports about the Mediterranean diet as a strategy to reach these goals. The VLCKD has been associated with better body weight reduction and lesser postoperative complications risk. However, the results in animal models are still controversial. When comparing VLCD with an LCD, there is no apparent superiority between one against the other one. However, LCD has shown better tolerance and adherence than VLCD. There is still a need for more controlled studies to define the best preoperative dietary treatment for weight loss before bariatric surgery since there are controversial positions regarding this issue.

The Peripheral Kynurenine Pathway and Psychosomatic Comorbidity in Subjects with Morbid Obesity Undergoing Bariatric Surgery

Background: The Kynurenine pathway (KP) is involved in various disorders, but little is known about the KP and psychosomatic complaints. The aim was to study the peripheral KP and psychosomatic comorbidity in subjects with morbid obesity. Methods: Psychosomatic comorbidity (perceived general health, muscle-skeletal pain, well-being, mood disorders, fatigue, self-esteem, sleepiness, and sense of humour) was registered, and serum samples were collected six months before and after bariatric surgery. Results: A total of 141 subjects (men/women, 116/25) with a mean age of 43.0 (SD 8.7) years and BMI of 42.1 (SD 3.8) kg/m2 were included. No significant associations were seen between the psychosomatic disorders and the KP. There was a significant downregulation of all KP metabolites after surgery, a reduction in CRP, and strong associations between CRP and the KP, particularly with the ratios of Kynurenine/Tryptophan and Quinolinic acid (QA)/Xanthurenic acid (XA). The QA/XA ratio was negatively associated with diabetes. Conclusions: The peripheral KP seemed to be of minor importance for the psychosomatic comorbidity in subjects with morbid obesity. The downregulation of all KP metabolites after bariatric surgery indicated reduced inflammation. The QA/XA ratio seemed to be a marker of insulin sensitivity and favourable glucose control.

Association between insurance-mandated precertification criteria and inpatient healthcare utilization during 1 year after bariatric surgery

BACKGROUND

Insurance-mandated precertification requirements are barriers to bariatric surgery. The value of their prescription, based on insurance type rather that the clinical necessity, is unclear.

OBJECTIVES

To determine whether there is an association between insurance-mandated precertification criteria for bariatric surgery and short-term inpatient healthcare utilization.

SETTING

Pennsylvania Health Care Cost Containment Council's inpatient care databases for the years 2016-2017.

METHODS

The study included 2717 adults who underwent bariatric surgery in Southeastern Pennsylvania in 2016. Postoperative length of stay and rehospitalizations for these individuals were followed using clinical and claims data during the first year after bariatric surgery.

RESULTS

The requirements for 3- to 6-month preoperative medical weight management, as well as pulmonology and cardiology examinations, were not associated with the patient length of stay, number of all-cause rehospitalizations, or number of all-cause rehospitalization days after adjusting for patient age, sex, race, ethnicity, the Elixhauser comorbidity score, type of the surgery, facility where the surgery was performed, primary payer type, and the estimated median household income. Among commercially insured individuals (n = 1499), the mean number of all-cause rehospitalizations during the study period was lower in patients with no medical weight management requirement by a factor of .57 (lower by 43.1%; 95% confidence interval, .35-.94, P = .03) and higher in patients with no requirement for preoperative cardiology and pulmonology evaluations by a factor of 2.09 (95% confidence interval 1.09-4.02, P = .03).

CONCLUSION

The findings suggest that the precertification requirement for preoperative medical weight management is not associated with a reduction in inpatient healthcare utilization in the first postoperative year.

Systematic Review and Meta-Analysis of the Effectiveness of Insurance Requirements for Supervised Weight Loss Prior to Bariatric Surgery

Many insurance plans impose strict criteria mandating preoperative weight loss attempts to limit patient's access to surgery. Preoperative acute weight loss has been hypothesized to reduce perioperative risk and to identify compliant patients who may have improved long-term weight loss. In this review, the evidence from studies examining clinical and weight loss outcomes both with and without preoperative weight loss are summarized. Although preoperative weight loss may have modest impact on some factors related to perioperative conduct, the evidence does not support these programs' effectiveness at promoting long-term weight loss. Provision of weight loss surgery should not be contingent on completion of insurance-mandated weight loss goals preoperatively, and these programs may, through patient attrition, actually do more harm than good.

Obesity, metabolic syndrome, and inflammation: an update for anaesthetists caring for patients with obesity

Our understanding of chronic inflammation in obesity is evolving. Suggested mechanisms include hypoxia of adipose tissue and a subsequent increase in circulating cytokines. It is now known that adipose tissue, far from being an inert tissue, produces and secretes multiple peptides that influence inflammation and metabolism, including substrates of the renin-angiotensin-aldosterone system (RAAS). RAAS blocking antihypertensive medication and cholesterol-lowering agents are now being evaluated for their metabolic and inflammation-modulating effects. Surgery also has pro-inflammatory effects, which may be exacerbated in patients with obesity. This narrative review will summarise the recent literature surrounding obesity, metabolic syndrome, inflammation, and interplay with the RAAS, with evidence-based recommendations for the optimisation of patients with obesity, prior to surgery and anaesthesia.

Examining the Rates of Obesity and Bariatric Surgery in the United States

PURPOSE

The aim of this study is to evaluate the change in rate of increase of bariatric surgery performed compared to the growth of obesity and severe obesity in the United States (US).

MATERIALS AND METHODS

The number of primary adult bariatric procedures performed in the US between 2015 and 2018 was obtained from the Metabolic and Bariatric Surgery Accreditation Quality and Improvement Project (MBSAQIP) database. The US Census database was used to derive age-adjusted obesity and severe obesity prevalence among adults. Prevalence of bariatric surgery, by year, was estimated as the ratio of the number of patients undergoing surgery and the projected number of eligible individuals for that year.

RESULTS

There were 627,386 bariatric procedures performed for body mass index (BMI) ≥ 30 kg/m², of which 73.3% (n = 459,800) were performed for BMI ≥ 40 kg/m². Although the rate of obesity increased by 3.32% per year during this period (RR = 1.0332 per year increase; 95% CI = 1.0313, 1.0352), the rate of surgery per eligible population increased by only 2.47% (RR = 1.0247 per year increase; 95% CI = 1.0065, 1.0432). The prevalence of severe obesity increased from 7.70% (n = 17,494,910) in 2015 to 9.95% (n = 23,135,039) in 2018 while the prevalence of surgery decreased from 0.588 per 100 eligible population in 2015 to 0.566 per 100 eligible population in 2018.

CONCLUSION

The rate of utilization has not kept up with the rate of increase in this disease, our costliest illness. There is a strong need to educate the public, healthcare professionals, insurance carriers, and legislators.

Current preoperative strategies applied in the Dutch bariatric centers: A national survey

There is no consensus about the optimal management of patients undergoing bariatric surgery. This study aimed to identify current weight loss goals prior to bariatric surgery, as well as aimed to explore preoperative strategies related to diet, nutritional supplements and physical activity. An online survey was distributed among bariatric surgeons and dietitians in all 18 Dutch bariatric centers. This survey included the following four domains: weight loss, diet, nutritional supplements and physical activity. For the analyses one answer per center was used, either the most common answer or the answer given by the most expert responder. All 18 centers reported at least one response. Preoperative weight loss was requested in 28% of the centers, whereas 61% desired a stable weight or weight loss, and 11% had no requests. A preoperative diet was routinely recommended in 78% of the centers and on indication (ie, depending on baseline weight and/or comorbidity status) in 22%. The most frequently prescribed diet was a low-energy diet (800-1500 kcal/day) in 44% of the centers. Nutritional supplements were recommended in 78% of the centers. Physical activity with low intensity was recommended in 83% of the centers, while physical exercise training with mid- to high-intensity was recommended in 72%. Inconsistent responses within centers were observed in 56% of the questions. The current bariatric practice within the Netherlands shows high variability and inconsistencies in preoperative management. Consensus-building and standardization of strategies should be promoted in the future.

Perioperative nutrition care and dietetic practices in the scope of bariatric surgery in Saudi Arabia using adapted protocols for evaluation

Objectives:

This study evaluates the availability of perioperative nutritional care protocols and the practices of bariatric registered dietitians in Saudi Arabia. The primary outcomes of the study were conducted using an adapted American survey “with permission.”

Methods:

A cross-sectional survey of a selected 32 dietitians providing bariatric services completed a self-administered online questionnaire from 12 hospitals in Jeddah, Saudi Arabia.

Results:

All surveyed dietitians were females, mainly Saudi nationals (93.9%, n = 30), and accredited by the Saudi Commission for Health Specialties (93.8%, n = 30). Only 37.5% (n = 6) of the dietitians were specialized in bariatric surgery. Perioperative common practices of dietitians included a conduct of screening for nutrition risk before (44%, n = 14) and after surgery (62.5%, n = 20) and applied a nutrition management protocol that is mainly based on the application of nutrition care process (62.5%, n = 20). Dietitians (81%, n = 26) reported the importance of having standardized protocols for nutritional management of patients undoing bariatric surgery, where 69% (n = 22) confirmed the availability of pre-operative written protocols in hospitals and 75% (n = 24) confirmed the existence of post-operative protocols. Pre-operative practices included using approaches for weight loss before surgery, for example, very low and low-calorie diet. Dietitians (25%, n = 8) see two to ten patients per month. The sleeve gastrectomy procedure is the most often performed surgery.

Conclusion:

This is the first study to evaluate the perioperative nutrition care protocols and practices related to bariatric surgery in Saudi Arabia. Perioperative bariatric protocols are available, but some dietitians are not aware of their availability and contents. Researchers emphasize the importance of creating national protocols by the Saudi Credentials Body to standardize practices within the field.

Structured Lifestyle Modification Prior to Bariatric Surgery: How Much is Enough?

Many healthcare systems require patients to participate in a structured lifestyle modification programme prior to bariatric surgery, even though bariatric consensus guidelines do not recommend this. While there is good evidence that such programmes improve health in other conditions such as metabolic and cardiovascular diseases, there is no evidence that they improve outcomes after bariatric surgery. The distinction needs to be drawn between the well-established need for individualised multidisciplinary dietetic and physical activity care for bariatric surgical patients and the potential harms from mandating participation in compulsory structured lifestyle programmes of fixed duration, frequency and intensity, which may delay surgery, reinforce obesity stigma, or both. Large clinical trials might help to address some of the uncertainty and provide an evidence base for clinicians and policymakers.

Nutritional Assessment and Preparation for Adult Bariatric Surgery Candidates: Clinical Practice

Bariatric surgery (BS) has proven to be highly efficacious in the treatment of obesity and its comorbidities. However, careful patient selection is critical for its success. Thus, patients should undergo medical, behavioral, and nutritional assessment by a multidisciplinary team. From the nutritional point of view, BS candidates should undergo nutritional assessment, preparation, and education by a registered dietitian in the preoperative period. Currently, detailed specified and comprehensive information on these topics is lacking. The present narrative review aimed to summarize the available literature concerning both the preoperative nutritional assessment components and the preoperative nutritional preparation and education components of patients planning to undergo BS. Current literature indicates that proper management before BS should include a comprehensive nutritional assessment, in which it is advisable to perform a clinical interview to assess patients' medical background, weight management history, eating patterns and pathologies, oral health, physical activity habits, nutritional status, supplementation usage, BS knowledge, surgery expectations and anthropometric measurements. Nutritional preparation and educational strategies should include an individualized preoperative weight-loss nutrition program, improvement of glycemic control, micronutrients deficiencies correction, eating and lifestyle habits adaptation, physical activity initiation, and strengthening knowledge on obesity and BS. At this stage, more well-designed intervention and long-term cohort studies are needed in order to formulate uniform evidence-based nutritional guidelines for patients who plan to undergo BS, including populations at higher nutritional risk. Moreover, postoperative outcomes of presurgical nutritional intervention programs should be studied.

A Qualitative Exploration of Patients' Experiences with Lifestyle Changes After Sleeve Gastrectomy in China

PURPOSE

Sleeve gastrectomy (SG) is the most widely used surgical treatment for severe obesity worldwide. Individuals who have undergone SG usually need to change lifestyle behaviors as a response to the anatomical changes imposed by SG, and patients need to sustain lifestyle changes for long-term surgical success. Little is known about how patients experience and manage lifestyle changes following SG. In China, where SG comprises over 70% of bariatric surgical procedures, there have been no reports addressing this issue. This study aimed to describe individuals' experiences related to lifestyle changes after SG in China.

MATERIALS AND METHODS

Semi-structured interviews were conducted at the Shanghai Huashan Hospital in China with adults who had undergone SG between 2012 and 2018. Two independent researchers used an interpretive thematic approach to analyze transcripts for themes and sub-themes.

RESULTS

Interviews (N = 15) revealed three major themes of participants' experiences with postoperative lifestyle changes: advantages outweigh disadvantages; developing self-management strategies (i.e., adopting new behaviors and developing habits, continuing self-monitoring, focusing on health over weight, staying determined); and experiencing culture-specific difficulties in adherence to follow-up visits and lifestyle recommendations.

CONCLUSION

The data from this study provided a rich description of the postoperative experiences of patients in China. Participants reported that surgical benefits supersede the surgery-related side effects, and participants were able to develop self-management strategies in order to achieve success. However, personal and social barriers, such as the challenges of applying postoperative dietary guidelines into daily practice, may impede patients making and sustaining recommended behavioral changes.

Clinical significance of diabetes control before metabolic surgery

BACKGROUND

Even though observational studies have suggested that poor preoperative diabetes control increases risk after major abdominal surgery, it is unclear whether this effect is seen in metabolic surgery patients.

OBJECTIVES

To determine whether poor preoperative diabetes control is associated with worse outcomes in patients with obesity and diabetes undergoing metabolic surgery.

SETTING

Metabolic and Bariatric Surgery Quality Improvement Project (MBSAQIP) database.

METHODS

Using the MBSAQIP 2017 and 2018 database and preoperative glycated hemoglobin (HbA1C) as a diabetes control surrogate, we examined the association between diabetes control and major outcomes of primary laparoscopic sleeve gastrectomy (SG) or Roux-en-Y gastric bypass (RYGB) in patients with diabetes and obesity. Multivariate logistic regression modeling examined five 30-day postoperative outcomes: composite serious complications (composite of 10 adverse events), composite infection (composite of 7 infectious complications), length of stay >5 days, reoperation, and readmission. Models were adjusted for multiple covariates.

RESULTS

In total, 26,674 patients with HbA1C data available within 30 days before metabolic surgery were included in the primary analysis and 35,884 patients with HbA1C data within 90 days before surgery were included in the sensitivity analysis. The mean body mass index (BMI) and preoperative HbA1C were 45.6 ± 8.2 kg/m² and 8.2 ± 2.7%, respectively. The incidence of 30-day postoperative infections and serious complications were 1.62% and 1.35%, respectively. Neither primary analysis nor sensitivity analysis demonstrated any association between higher HbA1C and worsening of 5 primary outcomes of interest. The odds ratio of an overall effect for SG was 1.01 (95% CI .98-1.03; P = .58) and for RYGB was .99 (95% CI .96-1.02; P = .41).

CONCLUSION

Suboptimal preoperative diabetes control is not associated with increased adverse events and should not delay metabolic surgery, as metabolic surgery is generally a safe procedure and intrinsically improves diabetes control.

Insurance Coverage Criteria for Bariatric Surgery: A Survey of Policies

BACKGROUND

Bariatric surgery remains underutilized at a national scale, and insurance company reimbursement is an important determinant of access to these procedures. We examined the current state of coverage criteria for bariatric surgery set by private insurance companies.

METHODS

We surveyed medical policies of the 64 highest market share health insurance providers in the USA. ASMBS guidelines and the CMS criteria for pre-bariatric evaluation were used to collect private insurer coverage criteria, which included procedures covered, age, BMI, co-morbidities, medical weight management program (MWM), psychosocial evaluation, and a center of excellence designation. We derive a comprehensive checklist for pre-bariatric patient evaluation.

RESULTS

Sixty-one companies (95%) had defined pre-authorization policies. All policies covered the RYGB, and 57 (93%) covered the LAGB or the SG. Procedures had coverage limited to center of excellence in 43% of policies (n = 26). A total of 92% required a BMI of 40 or above or of 35 or above with a co-morbidity; however, 43% (n = 23) of policies covering adolescents (n = 36) had a higher BMI requirement of 40 or above with a co-morbidity. Additional evaluation was required in the majority of policies (MWM 87%, psychosocial evaluation 75%). Revision procedures were covered in 79% (n = 48) of policies. Reimbursement of a second bariatric procedure for failure of weight loss was less frequently found (n = 41, 67%).

CONCLUSIONS

A majority of private insurers still require a supervised medical weight management program prior to approval, and most will not cover adolescent bariatric surgery unless certain criteria, which are not supported by current evidence, are met.

Do Mandated Weight Loss Goals Prior to Bariatric Surgery Improve Postoperative Outcomes?

BACKGROUND

Most patients pursuing bariatric surgery undergo mandated preoperative weight management programs. The purpose of this study was to assess whether preoperative mandated weight loss goals lead to improved perioperative morbidity, postoperative weight loss, and resolution of comorbidities.

METHODS

Data from patients who underwent primary laparoscopic Roux-en-Y gastric bypass (LRYGB), and laparoscopic sleeve gastrectomy (LSG) between October 2012 and October of 2015 was reviewed. Patients were divided in two groups: those with BMI of 35-45 were not required to achieve a weight loss goal prior to surgery (no-WLG group) while those with BMI > 45 were given a weight loss goal proportionate to their weight (WLG group). Body mass index (BMI), history of diabetes mellitus type-II (DM-II), hypertension (HTN), hyperlipidemia (HLD), and obstructive sleep apnea (OSA) were recorded at baseline and 4 years postoperatively. Length of hospital stay (LOS) and reinterventions were considered proxies for postoperative morbidity.

RESULTS

A total of 776 patients, 81.4% LRYGB, were included in the study (age 45.1 ± 11.9). There was no difference in %ΔBMI, DM-II, HDL, HTN, LOS, or reinterventions among the two groups at 4 years postoperatively in both LRNY and LSG patients. This lack of difference persisted even when patients with similar BMI (43-45 vs 45.01-47) were compared.

CONCLUSION

WLG group did not have decreased perioperative morbidity, nor improved weight loss and comorbidity resolution 4 years after surgery. While these findings should also be confirmed by multicenter trials, they question the value of mandated WLG prior to bariatric surgery as they seem ineffective and may limit patient access to surgery.

Association Between Medicaid Status, Social Determinants of Health, and Bariatric Surgery Outcomes

OBJECTIVE

To compare outcomes after bariatric surgery between Medicaid and non-Medicaid patients and assess whether differences in social determinants of health were associated with postoperative weight loss.

BACKGROUND

The literature remains mixed on weight loss outcomes and healthcare utilization for Medicaid patients after bariatric surgery. It is unclear if social determinants of health geocoded at the neighborhood level are associated with outcomes.

METHODS

Patients who underwent laparoscopic sleeve gastrectomy (SG) or Roux-en-Y gastric bypass (RYGB) from 2008 to 2017 and had ≥1 year of follow-up within a large health system were included. Baseline characteristics, 90-day and 1-year outcomes, and weight loss were compared between Medicaid and non-Medicaid patients. Area deprivation index (ADI), urbanicity, and walkability were analyzed at the neighborhood level. Median regression with percent total body weight (TBW) loss as the outcome was used to assess predictors of weight loss after surgery.

RESULTS

Six hundred forty-seven patients met study criteria (191 Medicaid and 456 non-Medicaid). Medicaid patients had a higher 90-day readmission rate compared to non-Medicaid patients (19.9% vs 12.3%, P < 0.016). Weight loss was similar between Medicaid and non-Medicaid patients (23.1% vs 21.9% TBW loss, respectively; P = 0.266) at a median follow-up of 3.1 years. In adjusted analyses, Medicaid status, ADI, urbanicity, and walkability were not associated with weight loss outcomes.

CONCLUSIONS

Medicaid status and social determinants of health at the neighborhood level were not associated with weight loss outcomes after bariatric surgery. These findings suggest that if Medicaid patients are appropriately selected for bariatric surgery, they can achieve equivalent outcomes as non-Medicaid patients.

Pre-specified Weight Loss Before Bariatric Surgery and Postoperative Outcomes

Bariatric surgery is increasing exponentially to address the steep rise in the prevalence of severe obesity. Most centers require pre-specified preoperative weight loss before allowing patients to receive surgery. We examined the current evidence surrounding the potential benefits of this requirement on postoperative outcomes. We reviewed the current literature by conducting a multistage advance electronic search in Ovid®/MEDLINE® and PubMed for publications indexed after 2008 reporting preoperative weight loss and postoperative outcomes. Thirteen original publications, three randomized control trials (RCT), and five systematic reviews that met inclusion criteria were included. These were analyzed with regards to weight loss before surgery and postoperative outcomes. There were varied reports regarding the significant effect of preoperative weight loss. Six of the original articles (50%) did not identify a significant difference in the outcome while two of the RCT (essentially the same patient population, started in 2007 and reanalyzed in 2009) demonstrated some advantage. A later RCT (2012) did not show any advantage, albeit in the short term. The results of the systematic reviews, some with heterogenic designs, show no conclusive evidence that weight loss before surgery conferred improved postoperative outcomes. There is not enough high-quality evidence to back up the requirement of pre-specified preoperative weight loss before receiving surgery. Further validation of the possible benefits of pre-specified preoperative weight loss may need to be carried out.

Weight loss after bariatric surgery: a comparison between delayed and immediate qualification according to the last resort criterion

BACKGROUND

In the Netherlands, patients only qualify for bariatric surgery when they have followed a 6-month mandatory weight loss program (MWP), also called the "last resort" criterion. One of the rationales for this is that MWPs result in greater weight loss.

OBJECTIVES

To determine weight loss during MWPs and the effect of delayed versus immediate qualification on weight loss 3 years after bariatric surgery.

SETTING

Outpatient clinic.

METHODS

This is a nationwide, retrospective study with prospectively collected data. All patients who underwent a primary bariatric procedure in 2016 were included. We compared weight loss between patients who did not qualify according to the last resort criterion at screening (delayed group) with patients that qualified (immediate group).

RESULTS

In total 2628 patients were included. Mean age was 44.4 years, 81.3% were female, and baseline BMI was 42.3 kg/m². Roux-en-Y gastric bypass (RYGB) was the most frequently performed surgery (77.0%), followed by sleeve gastrectomy (15.8%) and banded RYGB (7.3%). The delayed group (n = 831; 32%) compared with immediate group (n = 1797; 68%), showed less percentage of total weight loss (%TWL) during the MWP (1.7% versus 3.9%, P < .001) and time between screening and surgery was longer (42.3 versus 17.5 wk, P < .001). Linear mixed model analysis showed no significant difference in %TWL at 18- (P = .291, n = 2077), 24- (P = .580, n = 1993) and 36-month (P = .325, n = 1743) follow-up.

CONCLUSION

This study shows that delayed qualification for bariatric surgery compared with immediate qualification does not have a clinically relevant impact on postoperative weight loss 3 years after bariatric surgery.

Earlier Provision of Gastric Bypass Surgery in Canada Enhances Surgical Benefit and Leads to Cost and Comorbidity Reduction

Background: Effective provision of bariatric surgery for patients with obesity may be impeded by concerns of payers regarding costs or perceptions of patients who drop out of surgical programs after referral. Estimates of the cost and comorbidity impact of these inefficiencies in gastric bypass surgery in Canada are lacking but would aid in informing healthcare investment and resource allocation.

Objectives: To estimate total and relative public payer costs for surgery and comorbidities (diabetes, hypertension, and dyslipidemia) in a bariatric surgery population.

Methods: A decision analytic model for a 100-patient cohort in Canada (91% female, mean body mass index 49.2 kg/m², 50% diabetes, 66% hypertension, 59% dyslipidemia). Costs include surgery, surgical complications, and comorbidities over the 10-year post-referral period. Results are calculated as medians and 95% credibility intervals (CrIs) for a pathway with surgery at 1 year (“improved”) compared with surgery at 3.5 years (“standard”). Sensitivity analyses were performed to test independent contributions to results of shorter wait time, better post-surgical weight loss, and randomly sampled cohort demographics.

Results: Compared to standard care, the improved path was associated with reduction in patient-years of treatment for each of the three comorbidities, corresponding to a reduction of $1.1 (0.68–1.6) million, or 34% (26-41%) of total costs. Comorbidity treatment costs were 9.0- and 4.7-fold greater than surgical costs for the standard and improved pathways, respectively. Relative to non-surgical bariatric care, earlier surgery was associated with earlier return on surgical investment and 2-fold reduction in risk of prevalence of each comorbidity compared to delayed surgery.

Conclusions: Comorbidity costs represent a greater burden to payers than the costs of gastric bypass surgery. Investments may be worthwhile to reduce wait times and dropout rates and improve post-surgical weight loss outcomes to save overall costs and reduce patient comorbidity prevalence.

Diet approach before and after bariatric surgery

Bariatric surgery (BS) is today the most effective therapy for inducing long-term weight loss and for reducing comorbidity burden and mortality in patients with severe obesity. On the other hand, BS may be associated to new clinical problems, complications and side effects, in particular in the nutritional domain. Therefore, the nutritional management of the bariatric patients requires specific nutritional skills. In this paper, a brief overview of the nutritional management of the bariatric patients will be provided from pre-operative to post-operative phase. Patients with severe obesity often display micronutrient deficiencies when compared to normal weight controls. Therefore, nutritional status should be checked in every patient and correction of deficiencies attempted before surgery. At present, evidences from randomized and retrospective studies do not support the hypothesis that pre-operative weight loss could improve weight loss after BS surgery, and the insurance-mandated policy of a preoperative weight loss as a pre-requisite for admission to surgery is not supported by medical evidence. On the contrary, some studies suggest that a modest weight loss of 5-10% in the immediate preoperative period could facilitate surgery and reduce the risk of complications. Very low calories diet (VLCD) and very low calories ketogenic diets (VLCKD) are the most frequently used methods for the induction of a pre-operative weight loss today. After surgery, nutritional counselling is recommended in order to facilitate the adaptation of the eating habits to the new gastro-intestinal physiology. Nutritional deficits may arise according to the type of bariatric procedure and they should be prevented, diagnosed and eventually treated. Finally, specific nutritional problems, like dumping syndrome and reactive hypoglycaemia, can occur and should be managed largely by nutritional manipulation. In conclusion, the nutritional management of the bariatric patients requires specific nutritional skills and the intervention of experienced nutritionists and dieticians.

Predicting Responses to Bariatric and Metabolic Surgery

PURPOSE OF REVIEW

Bariatric surgery is today the most effective therapy for weight loss and reduction of comorbidity burden in patients with severe obesity. However, bariatric surgery does not benefit equally all the patients. A consistent variability in outcomes has been observed. Predicting responses to bariatric surgery could be an important tool in clinical practice, by improving patients' selection or by identifying patients in which more aggressive follow-up and post-operative intervention should be applied. Predictive factors for weight loss, weight regain, diabetes remission and recurrence are briefly reviewed in this paper.

RECENT FINDINGS

Many pre-operative factors have been proposed as negative or positive predictors of body weight reduction after surgery. However, none of these factors has been consistently demonstrated to have a sufficiently strong predictive power to influence eligibility to bariatric surgery itself. Weight regain can occur after bariatric surgery and its probability seems to be more influenced by post-operative behavioral factors than by pre-operative predictors. Several effective scores have been developed to predict diabetes remission after surgery, however long-term maintenance and diabetes recurrence after surgery seem again more influenced by post-operative behaviors and weight loss maintenance. In general, more attention and active interventions to pre-operative and post-operative eating behaviors and lifestyle modifications are probably more important at the clinical level than the search of pre-operative predictors of long-term outcomes.