Weight loss before gastric bypass: feasibility and effect on postoperative weight loss and weight loss maintenance

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.

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.

Does Preoperative Weight Loss Predict Significant Postoperative Weight Loss Among Patients who Underwent Laparoscopic Sleeve Gastrectomy?

Background Some bariatric practices, mainly those conducted under public-funded services, have adopted achieving a target preoperative weight loss (PrWL) before offering surgery. There are varied opinions on the correlation between preoperative and postoperative weight loss (PoWL) for the different surgical options. This study investigated the impact of target PrWL on PoWL for patients who underwent laparoscopic sleeve gastrectomy (LSG). Materials and methods A longitudinal retrospective cohort study was carried out on patients who had documented preoperative weight before LSG (n=155) from the authors' institution between February 2008 to October 2017. Patients were grouped into two cohorts based on meeting the 5% target PrWL or not. The endpoint included percent postoperative weight loss (% PoWL) at one year and two to three years. Results A total of 155 individuals were identified and analysed. Of these patients, 78.7% of them (n=122) achieved the 5% target PrWL (target group) while 21.3% (n= 33) did not (non-target group). At one year, there was no statistical significant difference in the mean % PoWL between the non-target and target groups (22.3 ± 8.1% versus 19.4 ± 11.8% p value= 0.08). A similar observation was made at two-three years, where the mean % PoWL in the non-target group was 14.7 ± 10.7% versus 16.3 ± 14.4% in the target group (p value= 0.07). Our further analysis highlighted a statistically significant weak inversely proportional correlation between % PrWL and % PoWL at one year and two to three years. Conclusion Meeting target PrWL does not significantly impact on PoWL after LSG. Therefore, it should not serve as exclusion criteria for eligible patients who are in need of surgery.

Short-Term Preoperative Weight Loss and Postoperative Outcomes in Bariatric Surgery

BACKGROUND

Preoperative weight loss is often encouraged before undergoing weight loss surgery. Controversy remains as to its effect on postoperative outcomes. The aim of this study was to determine what impact short-term preoperative excess weight loss (EWL) has on postoperative outcomes in patients undergoing primary vertical sleeve gastrectomy (SG) or Roux-en-Y gastric bypass (RYGB).

STUDY DESIGN

All patients who underwent SG (n = 167) or RYGB (n = 188) between 2014 and 2016 and who completed our program-recommended low calorie diet (LCD) for 4 weeks immediately preceding surgery were included. These patients (N = 355) were then divided into 2 cohorts and analyzed according to those who achieved ≥8% EWL (n = 224) during the 4-week LCD period and those who did not (n = 131). Primary endpoints included percent excess weight loss (% EWL) at 1, 3, 6, and 12 months postoperatively.

RESULTS

Patients achieving ≥8% EWL preoperatively experienced a greater % EWL at postoperative month 3 (42.3 ± 13.2% vs 36.1 ± 10.9%, p < 0.001), month 6 (56.0 ± 18.1% vs 47.5 ± 14.1%, p < 0.001), and month 12 (65.1 ± 23.3% vs 55.7 ± 22.2%, p = 0.003). Median operative duration (117 minutes vs 125 minutes; p = 0.061) and mean hospital length of stay (1.8 days vs 2.1 days; p = 0.006) were also less in patients achieving ≥8% EWL. No significant differences in follow-up, readmission, or reoperation rates were seen. Linear regression analysis revealed that patients who achieved ≥8% EWL during the 4-week LCD lost 7.5% more excess weight at postoperative month 12.

CONCLUSIONS

Based on these data, preoperative weight loss of ≥8% excess weight, while following a 4-week LCD, is associated with a significantly greater rate of postoperative EWL over 1 year, as well as shorter operative duration and hospital length of stay.

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.

Short-term carbohydrate-restricted diet for weight loss in severely obese women

BACKGROUND

Weight loss in bariatric pre-surgery period reduces surgical complications, surgery time, blood loss, and length of hospital stay. Carbohydrate-restricted diets have been used as an alternative for weight loss. We tested the efficacy of a low-calorie carbohydrate-restricted diet (RD) for short-term weight loss in women with severe obesity and evaluate its metabolic effects in relation to a conventional low-calorie diet (CD).

METHODS

The subjects received a 1,200-kcal diet with or without carbohydrate restriction for a period of 1 week in the hospital. Nineteen obesity class III women were distributed into two groups: experimental (n = 10) and control (n = 9). The following variables were assessed at the beginning and end of the study: anthropometric measurements, body composition, resting energy expenditure, substrate oxidation, and biochemical tests.

RESULTS

Compared with CD, RD led to larger weight loss (2.6 and 4.4 kg, respectively; p = 0.01) and waist circumference reduction (p < 0.01). Among the assessed biochemical indicators, only plasma and urine acetone levels were different (p < 0.01); higher values were found in the experimental group with no symptoms and other diet-related complaints. There was also a significant decrease in triglycerides and carbohydrate oxidation, as well as a significant enhancement in lipid oxidation in the RD group.

CONCLUSION

Short-term RD was more efficient than CD regarding quick weight loss and waist circumference reduction, which may favor gastroplasty. Also, RD did not lead adverse metabolic effects.

[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.

The Effect of Preoperative Weight Loss before Gastric Bypass: A Systematic Review

Background. Many insurance companies require obese patients to lose weight prior to gastric bypass. From a previous study by the same authors, preoperative weight at surgery is strongly predictive of weight loss up to one year after surgery. This review aims to determine whether preoperative weight loss is also correlated with weight loss up to one year after surgery. Methods. Of the 186 results screened using PubMed, 12 studies were identified. A meta-analysis was performed to further classify studies (A class, B class, regression, and rejected). Results. Of all 12 studies, one met the criteria for A class, six were B class, four were regression, and one was rejected. Six studies supported our hypothesis, five were inconclusive, and no study refuted. Conclusions. Preoperative weight loss is additive to postsurgery weight loss as predicted from the weight at the time of surgery.

Effect of preoperative weight loss in bariatric surgical patients: a systematic review

BACKGROUND

The potential benefit of preoperative weight loss in patients undergoing bariatric surgery has led many bariatric surgeons to recommend an aggressive weight reduction regimen to their patients. Some surgeons might withhold bariatric procedures if a certain threshold of preoperative weight loss is not achieved. It is unclear whether this practice has any scientific evidence supporting it. Our study aimed to examine the current evidence surrounding this issue in a systematic review. The setting was a university hospital.

METHODS

A systematic search of multiple databases, including MEDLINE, Google Scholar, EMBASE, the Cochrane Library, and conference proceedings were reviewed, yielding a final total of 27 studies. Of the 27 studies, 7 were prospective studies (2 randomized controlled trials from the same patient population), 14 were retrospective studies (2 chart reviews from the same patient population), 1 was an editorial, and a number were conference presentations.

RESULTS

A total of 17 trials, including approximately 4611 patients, deemed preoperative weight loss beneficial, and 10 studies, including 2075 patients, deemed preoperative weight loss to be of no benefit. The operative time was 12.5 minutes shorter for the preoperative weight loss patients undergoing laparoscopic Roux-en-Y gastric bypass. With regard to the effects of preoperative weight loss on postoperative weight loss, 9 studies (39%) reported a positive correlation, and 15 (62.5%) reported no benefit. Nine studies reporting perioperative complications (852 patients) revealed no difference in the complication rates, and 2 studies (1234 patients) suggested a significant decrease was associated with preoperative weight loss.

CONCLUSION

This systematic review suggests little evidence is available to support or refute the routine use of preoperative weight reduction in bariatric surgery. Clearly, a large-scale, multicenter, randomized, controlled trial with sufficient power is necessary to clarify this significant aspect of preoperative care.

Preoperative 4-week low-calorie diet reduces liver volume and intrahepatic fat, and facilitates laparoscopic gastric bypass in morbidly obese

BACKGROUND

The aim of this study was to explore changes in liver volume and intrahepatic fat in morbidly obese patients during 4 weeks of low-calorie diet (LCD) before surgery and to investigate if these changes would facilitate the following laparoscopic gastric bypass.

METHODS

Fifteen female patients (121.3 kg, BMI 42.9) were treated preoperatively in an open study with LCD (800-1,100 kcal/day) during 4 weeks. Liver volume and fat content were assessed by magnetic resonance imaging and spectroscopy before and after the LCD treatment.

RESULTS

Liver appearance and the complexity of the surgery were scored at the operation. Eighteen control patients (114.4 kg, BMI 40.8), without LCD were scored similarly. Average weight loss in the LCD group was 7.5 kg, giving a mean weight of 113.9 kg at surgery. Liver volume decreased by 12% (p < 0.001) and intrahepatic fat by 40% (p < 0.001). According to the preoperative scoring, the size of the left liver lobe, sharpness of the liver edge, and exposure of the hiatal region were improved in the LCD group compared to the controls (all p < 0.05).

CONCLUSIONS

The overall complexity of the surgery was perceived lower in the LCD group (p < 0.05), due to improved exposure and reduced psychological stress (both p < 0.05). Four weeks of preoperative LCD resulted in a significant decrease in liver volume and intrahepatic fat content, and facilitated the subsequent laparoscopic gastric bypass as scored by the surgeon.

Age and gender exert differential effects on blood lipids in patients after LAGB and LRYGB

BACKGROUND

Although bariatric surgery is known to exert favorable effects on dyslipidemia, few studies have systematically considered how the demographic variables might modulate the outcomes. The aim of the present study was to examine the interactive effects of gender, age, and surgery type on dyslipidimia in bariatric surgery patients at a tertiary hospital in the United States.

METHODS

In a retrospective review of 294 patients who had undergone laparoscopic Roux-en-Y gastric bypass (LRYGB) or laparoscopic adjustable gastric bypass (LAGB), we examined the changes in lipid profiles and antihyperlipidemic use for ≤4 years postoperatively. The data were analyzed using longitudinal mixed modeling methods, in which the effects on lipid concentrations and medication use were tested in models with gender, surgery type, age, postoperative duration, and all possible interactions entered as factors.

RESULTS

Significant 2-way interactions of surgery type*time were found for total cholesterol and high-density lipoprotein cholesterol, gender*time for high-density lipoprotein cholesterol, and age*time for triglycerides. A 3-way interaction of surgery type*age*time was noted for low-density lipoprotein cholesterol. For older patients, low-density lipoprotein cholesterol was reduced by 20% from baseline in the LRYGB group but did not lessen significantly in the LAGB group. In the younger patients, however, decreases from the preoperative concentrations were not evident in either surgery group. An interaction of surgery type*time on antihyperlipdemic medication use, in which values changed significantly from baseline was found in both groups. However, the pattern in the LRYGB patients opposed that in the LAGB patients.

CONCLUSION

Our results have demonstrated that bariatric surgery imparts a pronounced improvement in the blood lipid profile of recipients; however, these effects might be moderated by other factors, such as age and gender, independently of the baseline weight status of the patients.

Weight loss prior to bariatric surgery is not a pre-requisite of excess weight loss outcomes in obese patients

BACKGROUND

Although weight loss before bariatric surgery may carry advantages during the surgical procedure (decreased liver volume, operation duration, and blood loss), it is still debated whether it induces a greater long-term weight loss.

METHODS

We conducted a retrospective analysis over 539 patients operated by the same surgeon until September 2008. Five hundred seven primary bariatric surgical procedures were performed: gastric bypass in 381, gastric banding in 97, and sleeve gastrectomy in 29. Preoperative multidisciplinary care was similar for all the patients over a period of 12 months. Relationship between weight changes during this period and the percentage of excess weight loss (%EWL) over the 48 month after surgery was analyzed by logistic regression.

RESULTS

No relationship could be evidenced between pre- and postoperative weight loss, regardless of the surgical technique performed. Whether patients were male or female, and whether they had an initial BMI greater or lower than 50 kg/m(2), did not make a difference in the relationship between EWL at any point and weight loss prior to surgery. Despite a large range of weight changes before surgery, there was no trend for a relationship.

CONCLUSIONS

This study suggests that weight loss before surgery should not be considered a pre-requisite. Although it can reduce the difficulties of the surgical procedure, advantages for long-term weight loss are not validated.

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 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.

Benefits to patients choosing preoperative weight loss in gastric bypass surgery: new results of a randomized trial

BACKGROUND

Historically, preoperative weight loss has been encouraged for patients undergoing gastric bypass surgery to decrease liver mass, technically facilitating the procedure. In an earlier prospective randomized trial investigating effects of preoperative weight loss on patients' clinical outcomes, we reported no differences in postoperative complications or weight-loss profiles at 6-month followup. This article demonstrates results of the same study, with 1-year followup.

STUDY DESIGN

One hundred consecutive patients in an 18-month period preparing to undergo gastric bypass surgery at Stanford University Medical Center were selected. Fifty patients were randomly assigned to lose 10% or more of their excess body weight preoperatively, and 50 patients were assigned to no preoperative weight-loss requirements. After 1 year, patient demographics and data on postoperative complications, cure or improvement of comorbidities, and differences in weight-loss profiles were collected.

RESULTS

At 1 year, the 2 groups had similar preoperative demographics and body mass indexes (BMIs). Patients in the weight-loss group, on average, lost 8.2% of their excess body weight preoperatively compared with the nonweight-loss group, which gained 1.1% (p = 0.007). After a year, the patients in both arms of the study showed no difference in weight, BMI, excess weight-loss, and number of remaining comorbidites. But when patients were divided according to those who had lost at least 5% of their excess body weight preoperatively, the 1-year results for excess weight-loss, weight, and BMI were much lower for the weight-loss group.

CONCLUSIONS

Preoperative weight loss in patients undergoing gastric bypass surgery is safe and feasible. It should be encouraged, because it will markedly improve longterm weight loss.

Evaluating preoperative weight loss, binge eating disorder, and sexual abuse history on Roux-en-Y gastric bypass outcome

BACKGROUND

Roux-en-Y gastric bypass patients often undergo preoperative dieting and psychological assessment before surgery. We examined preoperative weight loss, binge eating disorder (BED), and sexual abuse history and the interactions of these predictors to determine whether a cautionary approach to Roux-en-Y gastric bypass is warranted.

METHODS

Consecutive subjects undergoing Roux-en-Y gastric bypass at our institution from January 1997 to December 2002 were reviewed. The postoperative excess weight loss (EWL) at 1, 3, 6, 12, 18, and 24 months and the perioperative complications were measured. EWL was compared at 12 and 24 months postoperatively in the categories of the presence/absence of preoperative weight loss, BED, and sexual abuse history. The perioperative complications were examined in the preoperative weight change groups.

RESULTS

Of 154 patients, 121 were included. No significant difference in EWL or perioperative complications was observed between those who lost or gained weight preoperatively. Of the 121 patients, 32% and 17% reported a history of BED and sexual abuse, respectively. No statistically significant difference was observed in the EWL between those with and without BED at 12 and 24 months postoperatively. The EWL in those with and without a sexual abuse history at 12 and 24 months was 57.67% and 66.32% (P <.05) and 64.40% and 70.97% (P = NS). No statistically significant interaction between EWL and sexual abuse*BED/sexual abuse*preoperative weight loss was observed.

CONCLUSION

Only sexual abuse history at postoperative month 12 had a negative effect on EWL. Otherwise, physicians can expect to see successful EWL in these subjects up to 24 months postoperatively. We recommend that additional investigation be done of those with BED and a sexual abuse history.

Does preoperative weight loss predict success following surgery for morbid obesity?

BACKGROUND

We analyzed preoperative weight loss as a predictor of postoperative success in patients after bariatric surgery.

METHODS

Data were obtained from a retrospective chart review of 562 patients in a multidisciplinary obesity clinic.

RESULTS

One hundred forty-six patients met the inclusion criteria (23 men and 123 women). The mean age was 39.5 years, and the mean body mass index (BMI) was 52.6 kg/m(2). Comorbid disease includes diabetes (15.7%), hypertension (30.8%), mental illness (38.4%), and musculoskeletal disease (56.8%). Procedures performed were 16 vertical band gastroplasties, 43 open gastric bypasses, 52 laparoscopic gastric bypasses, and 35 laparoscopic adjustable gastric bands. Preoperative weight change was as follows: 31 patients gained weight (21.2%), 56 patients lost weight (38.3%), and 59 patients maintained their weight (40.4%). Postoperative weight loss was not influenced by preoperative weight change among women. However, men who gained weight preoperatively had significantly worse outcomes.

CONCLUSIONS

Patients may achieve satisfactory early postoperative outcomes despite inconsistent or marginal preoperative weight change.