Predicting Bariatric Surgical Outcomes: Does Preoperative Weight Gain Correlate with Lesser Postoperative Weight Loss?

Variation in pre-operative insurance requirements for bariatric surgery

BACKGROUND

For patients who wish to undergo bariatric surgery, variation in pre-operative insurance requirements may represent inequity across insurance plan types. We conducted a cross-sectional assessment of the variation in pre-operative insurance requirements.

METHODS

Original insurance policy documents for pre-operative requirements were obtained from bariatric surgery programs across the entire USA and online insurance portals. Insurance programs analyzed include commercial, Medicaid, and Medicare/TriCare plans. Poisson regression adjusting for U.S. Census region was used to evaluate variation in pre-operative requirements. Analyses were done at the insurance plan level. Our primary outcome was number of requirements required by each plan by insurance type. Our secondary outcome was number of months required to participate in medically supervised weight loss (MSWL).

RESULTS

Among 43 insurance plans reviewed, representing commercial (60.5%), Medicaid (25.6%), and Medicare/TriCare (14.0%) plans, the number of pre-operative requirements ranged from 1 to 8. Adjusted Poisson regression showed significant variation in pre-operative requirements across plan types with Medicaid-insured patients required to fulfill the greatest number (4.1, 95%CI 2.7 to 5.4) compared to 2.7 (95%CI 2.2 to 3.2, P = 0.028) for commercially insured patients and 2.1 (95%CI 1.1 to 3.1, P = 0.047) for Medicare/TriCare-insured patients. Medicaid-insured patients were also required to complete a greater number of months in MSWL (6.6, 95%CI 5.5 to 7.6) compared to commercially (3.8, 95%CI 2.9 to 4.8, P < .001) and Medicare/TriCare-insured patients (1.7, 95%CI 0.3 to 3.0, P = .001).

CONCLUSION

The greater frequency of pre-operative requirements in Medicaid plans compared to Medicare/TriCare and commercial plans demonstrates inequity across insurance types which may negatively impact access to bariatric surgery. Pre-operative insurance requirements must be reevaluated and standardized using established evidence to ensure all individuals have access to this life-saving intervention.

Preoperative Weight Loss as a Predictor of Bariatric Surgery Postoperative Weight Loss and Complications

BACKGROUND

The association between preoperative weight loss and bariatric surgery outcomes remains unclear. We explored the utility of preoperative weight loss as a predictor of postoperative weight loss success. Additionally, we examined the association of preoperative weight loss with perioperative complication rates.

METHODS

Retrospective chart review of patients who underwent primary sleeve gastrectomy or primary Roux-en-Y gastric bypass for weight loss at a single institution between January 2003 and November 2017. Additional follow-up was obtained by a postoperative standardized patient questionnaire. Statistical analysis consisted of bivariate and multivariate logistic regression analysis.

RESULTS

Our study included 427 patients. Majority were female (n = 313, 73.3%) and underwent sleeve gastrectomy (n = 261, 61.1%). Average age was 45.6 years, and average follow-up was 6.3 years. Greater preoperative weight loss was associated with decreased length of stay (1.8 vs 1.3 days) in patients who underwent sleeve gastrectomy. Multivariable regression analysis revealed that preoperative weight loss was not associated with postoperative weight loss.

CONCLUSIONS

Preoperative weight loss is not predictive of postoperative weight loss success after bariatric surgery. Greater preoperative weight loss was associated with a mild decreased in length of stay but was not associated with a reduction in operative time, overall complication rates, ICU admissions, or intraoperative complications. The inconclusive literature and our findings do not support the medical necessity of weight loss prior to bariatric surgery for the purpose of reducing surgical complications or predicting successful postoperative weight loss success.

Meta-analysis of the influence of lifestyle changes for preoperative weight loss on surgical outcomes

Background

The aim was to investigate whether preoperative weight loss results in improved clinical outcomes in surgical patients with clinically significant obesity.

Methods

This was a systematic review and aggregate data meta-analysis of RCTs and cohort studies. PubMed, MEDLINE, Embase and CINAHL Plus databases were searched from inception to February 2018. Eligibility criteria were: studies assessing the effect of weight loss interventions (low-energy diets with or without an exercise component) on clinical outcomes in patients undergoing any surgical procedure. Data on 30-day or all-cause in-hospital mortality were extracted and synthesized in meta-analyses. Postoperative thromboembolic complications, duration of surgery, infection and duration of hospital stay were also assessed.

Results

A total of 6060 patients in four RCTs and 12 cohort studies, all from European and North American centres, were identified. Most were in the field of bariatric surgery and all had some methodological limitations. The pooled effect estimate suggested that preoperative weight loss programmes were effective, leading to significant weight reduction compared with controls: mean difference –7·42 (95 per cent c.i. –10·09 to –4·74) kg (P &lt; 0·001). Preoperative weight loss interventions were not associated with a reduction in perioperative mortality (odds ratio 1·41, 95 per cent c.i. 0·24 to 8·40; I2 = 0 per cent, P = 0·66) but the event rate was low. The weight loss groups had shorter hospital stay (by 27 per cent). No differences were found for morbidity.

Conclusion

This limited preoperative weight loss has advantages but may not alter the postoperative morbidity or mortality risk.

Efficacy of a Required Preoperative Weight Loss Program for Patients Undergoing Bariatric Surgery

The efficacy of mandatory medically supervised preoperative weight loss (MPWL) prior to bariatric surgery continues to be a controversial topic. The purpose of this observational study was to assess the efficacy of a MPWL program in a single institution, which mandated at least 10% excess body weight loss before surgery, by comparing outcomes of patients undergoing primary bariatric surgery with and without a compulsory preoperative weight loss regimen. We analyzed our database of 757 patients who underwent primary bariatric surgery between March 2008 and January 2015. Patients were placed into two cohorts based on their participation in a MPWL program requiring at least 10% excess weight loss (EWL) prior to surgery. Patients were evaluated at 3, 6, 12, and 24 months after surgery for weight loss, comorbidity resolution, and the occurrences of hospital readmissions. A total of 717 patients met the inclusion criteria of whom 465 underwent surgery without a preoperative weight loss requirement and 252 participated in the MPWL program. One year after surgery, 67.1% of non-participants and 62.5% of MPWL participants showed a resolution of at least one of five associated comorbidities (p = 0.45). Non-participants showed an average of 58.6% EWL, while MPWL participants showed 59.1% EWL at 1 year postoperatively (p = 0.84). Readmission rates, excluding those which were ulcer-related, at 30 days (3.4 vs. 6.40%, p = 0.11) and 90 days (9.9 vs. 7.5%, p = 0.29) postoperatively were not significantly different between the non-participants and MPWL patients, respectively. A mandatory preoperative weight loss program prior to bariatric surgery did not result in significantly greater %EWL or comorbidity resolution 1 year after surgery compared to patients not required to lose weight preoperatively. Additionally, the program did not result in significantly lower 30- or 90-day readmission rates for these patients. The value of a MPWL program must be weighed against the potential loss of bariatric surgery candidates. Patients who fail to lose 10% excess weight preoperatively are thus ineligible for a procedure from which they would otherwise benefit. Our data suggest these patients will have similar positive outcomes.

Weight loss before gastric bypass and postoperative weight change: data from the Scandinavian Obesity Registry (SOReg)

BACKGROUND

Weight loss before bariatric surgery has been found to be associated with reduced rates of postoperative complications.

OBJECTIVE

To evaluate whether preoperative weight loss was also associated with improved postoperative weight loss over time and if this was dependent on preoperative body mass index (BMI).

SETTING

Data from the Swedish national registry for bariatric surgery.

METHODS

Out of 20,564 patients undergoing primary gastric bypass from January 1, 2008 to November 30, 2011, 9570 with complete data on preoperative weight loss and 2 years postoperative weight loss were analyzed.

RESULTS

Total preoperative weight loss in the 25th, 50th, and 75th percentiles was 0%, 4.5%, and 8.6%, respectively. When comparing patients in the 50th percentile for preoperative weight loss with those in the 25th percentile, total postoperative weight loss was 5.0% and 5.3% higher at 1 and 2 years, respectively (P<.001). Corresponding values for patients in the 75th percentile for preoperative weight loss were 11.8% and 10.1% (P< .001). For patients in the 75th percentile of preoperative BMI (>45.7 kg/m(2)) the effect was even more pronounced. Thus, in this group of patients and within the 75th percentile for preoperative weight loss, the total weight reduction after 1 and 2 years was 15.2% and 13.6% higher compared with patients in the 25th percentile for preoperative weight loss.

CONCLUSION

In this Swedish national bariatric registry data set, weight loss before gastric bypass was associated with sustained improved postoperative weight reduction. Moreover, there was a relationship between the degree of pre- and postoperative weight loss and the relationship was stronger in patients with high BMI.

Does Preoperative Weight Change Predict Postoperative Weight Loss After Laparoscopic Sleeve Gastrectomy?

Background: Some institutions and insurance companies mandate a preoperative weight loss regimen prior to bariatric surgery. Previous studies suggest little to no correlation between preoperative and postoperative weight loss for laparoscopic Roux-en-Y gastric bypass (RNYGB). This study examined the impact of preoperative weight change for patients undergoing laparoscopic sleeve gastrectomy (LSG). Materials and Methods: A retrospective analysis was performed on patients undergoing LSG at the authors' institution from 2010 to 2012. Patients were grouped based on preoperative weight gain or loss. The correlation between preoperative BMI change and postoperative BMI change was studied, as well as length of surgery. Results: Of 141 patients with 1-year follow-up, 72 lost, six maintained, and 64 gained weight preoperatively. Percentage of excess BMI loss at 1 year was not statistically different between those who lost weight and those who gained weight. Percent change in BMI from initial visit to surgery does not correlate with change in BMI at 1 year postoperatively or with length of surgery. Conclusions: Preoperative weight loss is not a reliable predictor of postoperative weight loss or shorter operative time after LSG. Potential patients who otherwise meet indications for LSG should not be denied based on inability to lose weight.

Weight loss prior to bariatric surgery: an updated review of the literature

BACKGROUND AND AIMS

Prior to bariatric surgery, a preoperative weight-reducing regimen is usually adhered to in most centers. The clinical effects of such a regimen are yet to be determined.

MATERIAL AND METHODS

We reviewed the current literature by searching in PubMed for publications reporting clinical effects resulting from a preoperative weight loss regimen prior to bariatric surgery published from January 1, 1995 to April 30, 2014.

RESULTS

In total, we identified 23 original publications and 2 review articles which met all inclusion criteria. These were included and fully analyzed with regard to effects of preoperative weight loss. In general, for parameters such as operating time and intraoperative complications including blood loss and recovery, inconsistent data were reported. Most studies included low number of patients and with heterogenic designs, and the results could not form the base for recommendations. However, for outcomes such as postoperative complications and weight development over time, data from large-scale studies and randomized controlled trials suggest beneficial effects following adherence to weight loss prior to bariatric surgery.

CONCLUSION

Although a large amount of data in the current literature on the effects of weight loss prior to bariatric surgery are inconsistent for many outcome parameters, recently published results regarding effects on postoperative complications and weight development over time strongly suggest that such a regimen should be recommended. Whether a certain degree of weight loss should be mandatory before being accepted for bariatric surgery is, however, still controversial.

Preoperative predictors of weight loss following bariatric surgery: systematic review

BACKGROUND

Obesity affects 32% of adults in the USA. Surgery generates substantial weight loss, but 20-30% fails to achieve successful weight loss. Our objective was to identify preoperative psychosocial factors associated with weight loss following bariatric surgery.

METHODS

We performed a literature search of PubMed® and the Cochrane Database of Reviews of Effectiveness between 1988 and April 2010. Articles were screened for bariatric surgery and weight loss if they included a preoperative predictor of weight loss: body mass index (BMI), preoperative weight loss, eating disorders, or psychiatric disorder/substance abuse. One thousand seven titles were reviewed, 534 articles screened, and 115 included in the review.

RESULTS

Factors that may be positively associated with weight loss after surgery include mandatory preoperative weight loss (7 of 14 studies with positive association). Factors that may be negatively associated with weight loss include preoperative BMI (37 out of 62 studies with negative association), super-obesity (24 out of 33 studies), and personality disorders (7 out of 14 studies). Meta-analysis revealed a decrease of 10.1% excess weight loss (EWL) for super-obese patients (95% confidence interval (CI) [3.7-16.5%]), though there was significant heterogeneity in the meta-analysis, and an increase of 5.9% EWL for patients with binge eating at 12 months after surgery (95% CI [1.9-9.8%]).

CONCLUSIONS

Further studies are necessary to investigate whether preoperative factors can predict a clinically meaningful difference in weight loss after bariatric surgery. The identification of predictive factors may improve patient selection and help develop interventions targeting specific needs of patients.

Pre-bariatric surgery weight loss requirements and the effect of preoperative weight loss on postoperative outcome

Pre-bariatric surgery requirements vary between surgeons and surgical centers, with standards of practice not yet established. The goal of this systematic review was to summarize and evaluate the available literature on pre-bariatric surgery weight loss requirements and the relation between preoperative weight loss and postoperative outcome. Major databases, including Medline, PubMed and PsychINFO were searched for relevant articles. Case studies, studies>20 years old and studies that utilized self-reported body weight data were excluded. Data on the effect of the following was summarized: (1) preoperative requirements on preoperative weight loss; (2) insurance-mandated preoperative requirements; (3) the contingency of receipt of surgery; (4) preoperative weight loss on postoperative weight loss and (5) preoperative weight loss on perioperative and postoperative complication and comorbidity rates. The majority of studies suggest that: (1) current preoperative requirements held by the majority of third party payer organizations in the United States are ineffective in fostering preoperative weight loss; (2) making receipt of surgery contingent upon achieving preoperative weight loss, and meal-replacement diets, may be particularly effective in fostering preoperative weight loss and (3) preoperative weight loss may lead to improvements in at least some relevant postoperative outcomes. However, a preoperative weight loss mandate may lead to the denial of surgery and subsequent health benefits to individuals who are unable to achieve a prespecified amount of weight. Overall, the limited number and quality of prospective studies in this area prohibits the much-needed establishment of standards of practice for pre-bariatric requirements.

[Preoperative weight loss in bariatric surgery candidate patients. evidence-based recommendations]

INTRODUCTION

Bariatric surgery is becoming increasingly more common in the treatment of morbid obesity in our hospitals. One of the measures being used to optimise the results of this surgery seems to be the standardising the preoperative weight loss. As there are no universal recommendations for carrying out this weight loss, a review of this topic is presented.

OBJECTIVES

To analyse whether sufficient scientific evidence exists to recommend preoperative weight loss in candidate patients for bariatric surgery. What would be the best options to carry out this weight loss is also analysed, as well as making some recommendations based on the scientific evidence.

RESULTS

There is great heterogeneity in the designs of the different studies, with different guidelines for weight loss and various surgical techniques. However, preoperative weight loss leads to a decrease in the size of the liver and intra-abdominal fat, which improves the surgical field and intra-operative view, which in turn helps during the surgical act, both in open as well as laparoscopic surgery. There is no consensus on the effect of preoperative weight loss has in predicting the medium or long term results after bariatric surgery.

CONCLUSION

The current scientific evidence makes preoperative weight loss recommendable in candidate patients for bariatric surgery. However, there is no consensus on what is the best procedure to achieve this preoperative weight loss.

Effectiveness of a prebariatric surgery insurance-required weight loss regimen and relation to postsurgical weight loss

Most US insurance companies require patients to participate in a medically supervised weight loss regimen prior to bariatric surgery. However, the utility of this requirement has not been documented. Data was collected from 94 bariatric surgery patients who were required, and 59 patients who were not required, by their insurance company to participate in a presurgical weight loss regimen. Weight change in the required group, as well as group differences in weight change, was examined from 3 and 6 months presurgery to 1 week presurgery, and from 1 week presurgery to 3 months postsurgery. Weight change presurgery was then used to predict weight loss postsurgery. In the 6 months prior to surgery, required patients gained 3.7 kg +/- 5.9 (s.d.) (P < 0.0005), which did not differ from nonrequired patients. From surgery to 3 months postsurgery, required patients lost 23.6 +/- 8 kg (P < 0.0005), also without differing from nonrequired patients. Patients who gained more weight prior to surgery, lost more weight postsurgery (P = 0.001), while controlling for initial weight. Findings suggest that the common weight loss regimen requirements of US insurance carriers were ineffective in producing presurgical weight loss in this sample. Most patients (>70%) in this sample gained weight prior to surgery, potentially taking advantage of final opportunities to overindulge in preferred foods. Required patients fared no better in terms of weight change postsurgically and, surprisingly, presurgical weight gain predicted better postsurgical weight loss outcome. Several potential explanations for this finding are offered.

Does Preoperative Weight Change Predict Postoperative Weight Loss after Laparoscopic Roux-en-Y Gastric Bypass in the Short Term?

Background. Many institutions mandate preoperative weight loss prior to bariatric surgery. This study examines the correlation between preoperative weight change and postoperative success following laparoscopic Roux-en-Y gastric bypass. Methods. We retrospectively studied the correlation between change in BMI before surgery and change in BMI postoperatively, using linear regression analyses and one-way ANOVA, in 256 consecutive gastric bypass patients with 1-year followup. Results. Of 256 patients, 125 lost weight preoperatively (mean -1.7% BMI), while 131 maintained or gained weight (mean +1.2% BMI). Postoperatively, there was no significant difference in percent BMI loss between the two groups (34.6% and 34.5%). The percent change in BMI preoperatively did not predict postoperative BMI change after 1 year (P = n.s.). Conclusions. Our study did not show any correlation between preoperative weight change and postoperative weight loss after Roux-en-Y gastric bypass. Therefore, we do not believe that potential patients should be denied bariatric surgery on the basis of their inability to lose weight preoperatively.

Does weight loss immediately before bariatric surgery improve outcomes: a systematic review

BACKGROUND

Preoperative weight loss before bariatric surgery has been proposed as a predictive factor for improved patient compliance and the degree of excess weight loss achieved after surgery. In the present study, we sought to determine the effect of preoperative weight loss on postoperative outcomes.

METHODS

A search of MEDLINE was completed to identify the patient factors associated with weight loss after bariatric surgery. Of the 909 screened reports, 15 had reported on preoperative weight loss and the degree of postoperative weight loss achieved. A meta-analysis was performed that compared the postoperative weight loss and perioperative outcomes in patients who had lost weight preoperatively compared to those who had not.

RESULTS

Of the 15 articles (n = 3404 patients) identified, 5 found a positive effect of preoperative weight loss on postoperative weight loss, 2 found a positive short-term effect that was not sustained long term, 5 did not find an effect difference, and 1 found a negative effect. A meta-analysis revealed a significant increase in the 1-year postoperative weight loss (mean difference of 5% EWL, 95% confidence interval 2.68-7.32) for patients who had lost weight preoperatively. A meta-analysis of other outcomes revealed a decreased operative time for patients who had lost weight preoperatively (mean difference 23.3 minutes, 95% confidence interval 13.8-32.8).

CONCLUSION

Preoperative weight loss before bariatric surgery appears to be associated with greater weight loss postoperatively and might help to identify patients who would have better compliance after surgery.

Preoperative weight gain does not predict failure of weight loss or co-morbidity resolution of laparoscopic Roux-en-Y gastric bypass for morbid obesity

BACKGROUND

Success with preoperative weight loss (PWL) is often mandated by the bariatric team to assess patient compliance and has been suggested to correlate with improved postoperative weight loss outcomes.

METHODS

We performed a retrospective analysis of 1629 consecutive patients undergoing laparoscopic Roux-en-Y gastric bypass at Duke University Medical Center. Patients with a preoperative weight gain (PWG) or loss of > or =10 lb were compared. Patients with <12 months of follow-up were excluded.

RESULTS

We found no difference between the 2 groups (PWG, n = 115, PWL, n = 88) with regard to age, gender, race, preoperative body mass index, presence of co-morbidities, or interval between the initial program-entry weight and surgery (149 versus 141 d). No difference was found in the percentage of excess weight loss (EWL) at 12 months, when calculated using the patient's immediate preoperative weight (PWG group, 63.5% EWL versus PWL group, 63.9% EWL, P = NS). If the %EWL was calculated using the initial program-entry weight, the PWL did confer a transient postoperative weight loss advantage; however, this did not persist past 24 months postoperatively. At both 12 and 24 months, the resolution rates of diabetes (82% versus 83% at 2 yr; P = NS), hypertension (48% versus 42% at 2 yr, P = NS), and continuous positive airway pressure discontinuation (87% versus 87% at 1 yr, P = NS) were equivalent. No differences in perioperative complications or conversion rates were detected. The operative time was slightly longer for the PWG group (119.7 versus 104.9 min, P = .02).

CONCLUSION

The results of our study have shown that weight loss before laparoscopic Roux-en-Y gastric bypass is not mandatory and might deter patients from considering weight loss surgery. Laparoscopic Roux-en-Y gastric bypass can be performed safely with equivalent co-morbidity resolution and %EWL regardless of PWG or PWL.