Nutritional consequences of adjustable gastric banding and gastric bypass: a 1-year prospective study. Obes Surg. 2009;19:56-65. [PMID: 18542847 DOI: 10.1007/s11695-008-9571-2]

Predictive factors of weight loss 1 year after laparoscopic gastric bypass in obese patients

BACKGROUND

Substantial weight loss is achieved in majority of severely obese subjects undergoing laparoscopic gastric bypass (LGBP) but some fail to obtain expected results. Our aim was to identify preoperative factors that could influence weight loss (WL) 1 year after LGBP.

METHODS

We studied the predictive value of clinical, biological, and dietary preoperative factors on weight loss in obese patients referred for LGBP. WL was assessed according to mean absolute weight loss (AWL) and mean percent excess weight loss (%EWL) 1 year after LGBP.

RESULTS

One hundred twenty-three subjects were included (112 women, age 42 ± 10 years; weight 127 ± 23 kg; BMI 47 ± 8 kg/m(2)). Mean AWL was 39.4 ± 10.5 kg at 1 year, corresponding to a mean %EWL of 70.5 ± 21.2%. AWL was positively correlated with initial weight, BMI, and energy intake and negatively with age, female sex, and treatment for hypertension and diabetes. %EWL was negatively correlated with initial weight, BMI, and positively correlated with triglycerides and ferritinemia. In multivariate analysis, %EWL was negatively correlated only with initial BMI (p < 0.001). AWL was positively correlated with initial BMI and male sex (both p < 0.001), and negatively correlated with protein intake (p = 0.039) and treatment for diabetes (p = 0.021), but not with biomarkers of diabetes and insulin resistance.

CONCLUSION

Initial BMI appears to be a strong determinant of individual WL, but predictive factors differ when WL was expressed as %EWL or AWL. The treatment of diabetes rather than diabetes itself appears to affect WL.

Long-term results of bariatric restrictive procedures: a prospective study

Laparoscopic adjustable gastric banding (LAGB) and vertical-banded gastroplasty (VBG) are surgical treatment modalities for morbid obesity. This prospective study describes the long-term results of LAGB and VBG. One hundred patients were included in the study. Fifty patients underwent LAGB and 50 patients, open VBG. Study parameters were weight loss, changes in obesity-related comorbidities, long-term complications, re-operations including conversions to other bariatric procedures and laboratory parameters including vitamin status. From 91 patients (91%), data were obtained with a mean follow-up duration of 84 months (7 years). Weight loss [percent excess weight loss (EWL)] was significantly more after VBG compared with LAGB, 66% versus 54%, respectively. All comorbidities significantly decreased in both groups. Long-term complications after VBG were mainly staple line disruption (54%) and incisional hernia (27%). After LAGB, the most frequent complications were pouch dilatation (21%) and anterior slippage (17%). Major re-operations after VBG were performed in 60% of patients. All re-operations following were conversions to Roux-en-Y gastric bypass (RYGB). In the LAGB group, 33% of patients had a refixation or replacement of the band, and 11% underwent conversion to another bariatric procedure. There were no significant differences in weight loss between patients with or without re-interventions. No vitamin deficiencies were present after 7 years, although supplement usage was inconsistent. This long-term follow-up study confirms the high occurrence of late complications after restrictive bariatric surgery. The failure rate of 65% after VBG is too high, and this procedure is not performed anymore in our institution. The re-operation rate after LAGB is decreasing as a result of new techniques and materials. Results of the re-operations are good with sustained weight loss and reduction in comorbidities. However, in order to achieve these results, a durable and complete follow-up after restrictive procedures is imperative.

Zinc deficiency: a frequent and underestimated complication after bariatric surgery

BACKGROUND

Although zinc deficiency is common after bariatric surgery, its incidence is underestimated. The objective was to monitor zinc and nutritional status before and 6, 12 and 24 months (M6, M12 and M24) after gastric bypass (Roux-en-Y gastric bypass), sleeve gastrectomy and biliopancreatic diversion with duodenal switch (DS) in patients receiving systematised nutritional care.

METHODS

Data for 324 morbidly obese patients (mean body mass index 46.2 ± 7.3 kg/m(2)) were reviewed retrospectively. The follow-up period was 6 months for 272 patients, 12 months for 175, and 24 months for 70. Anthropometric, dietary and serum albumin, prealbumin, zinc, iron and transferrin saturation measures were determined at each timepoint.

RESULTS

Nine percent of patients had zinc deficiency pre-operatively. Zinc deficiency was present in 42.5% of the population at M12 and then remained stable. Zinc deficiency was significantly more frequent after DS, with a prevalence of 91.7% at M12. Between M0 and M6, variation in plasma prealbumin, surgery type and zinc supplementation explained 27.2% of the variance in plasma zinc concentration. Surgery type explained 22.1% of this variance between M0 and M24. Mean supplemental zinc intake was low (22 mg/day). The percentage of patients taking zinc supplementation at M6, M12 and M24 was 8.9%, 20.6% and 29%, respectively.

CONCLUSIONS

Reduced protein intake, impaired zinc absorption and worsening compensatory mechanisms contribute to zinc deficiency. The mechanisms involved differ according to the type of surgery and time since surgery. Zinc supplementation is necessary early after bariatric surgery, but this requirement is often underestimated or is inadequate.

Protein intake, body composition, and protein status following bariatric surgery

BACKGROUND

Daily protein intake recommendations have recently been proposed for the bariatric patient. We aimed to evaluate the accomplishment of these recommendations, and the influence of protein intake (PI) on fat free mass (FFM) and protein status changes following bariatric surgery.

METHODS

We examined 101 consecutive patients undergoing laparoscopic Roux-in-Y gastric gypass (LGBP) or laparoscopic sleeve gastrectomy (LSG). Based on 3-day food records, PI from food and supplements were quantified at 4, 8, and 12 months after surgery. The association between PI and body composition (bioelectrical impedance), plasma albumin and pre-albumin was evaluated at all study time points.

RESULTS

A PI <60 g/day was present respectively in 45%, 35%, and 37% of the cohort at 4, 8, and 12 months after surgery (p < 0.001 relative to baseline). Despite our universal recommendation of protein supplementation, supplements were taken only by 63.4, 50.5, and 33.7% of the participants at 4, 8, and 12 months. However, protein supplementation was effective in helping patients to achieve the daily protein intake goal. In linear regression analysis, male gender and weight loss, but not PI, were significantly associated with loss of FFM (p < 0.001). No significant correlation between PI and plasma albumin or pre-albumin was found.

CONCLUSIONS

Our study underscores the value of protein supplementation for the achievement of the recommended daily protein intake in the bariatric patient. However, our data does not help to define a PI goal as critical in determining the FFM and protein status changes following LGBP or LSG.

Changes in eating behavior after laparoscopic adjustable gastric banding: a systematic review of the literature

This systematic review evaluates the current evidence base for eating behavior changes after laparoscopic adjustable gastric banding (LAGB). A literature search from 1990 to February 2010 was conducted to identify original studies that assessed eating behavior in adults who have undergone LAGB. Sixteen articles (14 separate studies) met inclusion criteria. Although strength of the evidence base was limited by observational study designs and methodological weaknesses, results suggest that positive changes in eating behavior occur after surgery, including reduced over-eating in response to emotional and situational cues. There is some evidence to suggest that uncontrolled eating behaviors persist in some individuals, and that this may be problematic for weight loss after surgery. Few studies examined the relationship between changes in eating behavior and weight loss; thus, optimal behavioral strategies for promoting positive weight outcomes remain unclear. Further interventional research addressing the inherent limitations of the current-evidence base is required to guide development of evidence-based management guidelines for LAGB in future.

Obstetrical and neonatal outcomes of pregnancies following gastric bypass surgery: a retrospective cohort study in a French referral centre

BACKGROUND

The objective of this study was to analyze obstetrical and neonatal outcomes following Roux en Y Gastric Bypass procedures (RYGBP).

METHODS

A retrospective cohort study was conducted in a single French tertiary perinatal care and bariatric center. The study involved 24 pregnancies, following RYGBP (exposed group) and two different control groups (non-exposed groups). A body mass index (BMI)-matched control group included 120 pregnancies matched for age, parity, and pregnancy BMI. A normal BMI control group included 120 pregnancies with normal BMI (18.5-24.9 kg/m(2)), matched for age and parity. Hospital data were reviewed from all groups in the same 6-year period. Obstetrical and neonatal outcomes after RYGB were compared, separately, to the two different-matched control groups.

RESULTS

The median interval from RYGBP to conception was 26.6 (range: 3-74) months. Rates of perinatal complications did not differ significantly between the RYGBP group and normal BMI and BMI-matched controls groups. The rate of Cesarean section before labor was higher in the RYGBP patients than in the normal BMI control group (25% vs. 9.3% respectively, p = 0.04). Weight gain was lower in the RYGBP patients than normal BMI control group (5.8 kg vs. 13.2 kg respectively, p < 0.0001). Birthweight was also lower in the RYGBP group than those in normal BMI and BMI-matched controls groups (2,948.2 g vs. 3,368.2 g and 3,441.8 g, respectively, p < 0.0001).

CONCLUSIONS

RYGBP surgery was associated with reduced birthweight, suggesting a possible role of nutritional growth restriction in pregnancy.

Nutritional pyramid for post-gastric bypass patients

BACKGROUND

Life-long nutrition education and diet evaluation are key to the long-term success of surgical treatment of obesity. Diet guidelines provided for bariatric surgery patients generally focus on a progression through dietary stages, from the immediate post-surgical period to 6 months after surgery. However, long-term dietary guidelines for those surgically treated for obesity are not readily available. Therefore, there is a need for dietary recommendations for meal planning and nutritional supplementation for bariatric surgery patients beyond the short-term, post-operative period. The purpose of this paper is to construct an educational tool to provide long-term nutritional and behavioral advice for the post-bariatric patient.

METHODS

The manuscript summarizes the current knowledge on dietary strategies and behaviors associated with beneficial nutritional outcomes in the long term of post-bariatric surgery patients.

RESULTS

Dietary and nutritional recommendations are presented in the form of a "bariatric food pyramid" designed to be easily disseminated to patients.

CONCLUSIONS

The development of educational tools that are easy to understand and follow is essential for effective patient management during the surgery follow-up period. The pyramid can be used as a tool to help both therapists and patients to understand nutrition recommendations and thus promote a healthy long-term post-op dietary pattern based on high-quality protein, balanced with nutrient-dense complex carbohydrates and healthy sources of essential fatty acids.

Prevalence of anemia after Roux-en-Y gastric bypass surgery: what is the right number?

BACKGROUND

The reported prevalence of anemia after malabsorptive bariatric surgery has varied from 5% to 64% in the post-Roux-en-Y gastric bypass (RYGB) population, owing to the small study sample sizes and generally poor follow-up in surgical referral practices. The present study estimated the prevalence of anemia in the post-RYGB population and determined whether an integrated healthcare system with a shared electronic medical record could improve postoperative follow-up.

METHODS

The medical records from 1009 sequential patients who had undergone RYGB from 2000 to 2005 were retrospectively analyzed. All anemia data within the healthcare system's electronic medical record were accessible.

RESULTS

Of the 1009 medical records, 720 contained ≥1 year of follow-up data concerning anemia. Anemia had developed or worsened in 259 patients, for a prevalence of 36% in the present sample. The anemia was moderate to severe (hemoglobin <10 g/dL) in 88 patients (12.2%.), many of whom subsequently required parenteral iron. Of the 1009 patients, the follow-up data for ≥3 years concerning anemia were available for only 357 patients (35.4%).

CONCLUSION

The results of the present study have shown that in a large population of patients undergoing RYGB, the prevalence of anemia was great enough to justify more intensive long-term screening. We hope the findings from the present report influence the national screening standards for this patient population.

Micronutrient-related neurologic complications following bariatric surgery

Nearly two thirds of American adults are either overweight or obese. Accordingly, bariatric surgery experienced explosive growth during the past decade. Current estimates place the worldwide volume of bariatric procedures at greater than 300,000 cases annually. Micronutrient deficiencies are well-described following bariatric surgery, and they may present with devastating and sometimes irreversible neurologic manifestations. Clinical symptoms range from peripheral neuropathy to encephalopathy, and are most commonly caused by thiamine, copper, and B(12) deficiencies.

Incidence and risk factors for the development of anemia following gastric bypass surgery

AIM: To evaluate the incidence and risk factors for the development of anemia after Roux-en-Y gastric bypass (RYGB).

METHODS: A retrospective analysis of patients undergoing RYGB from January 2003 to November 2007 was performed. All patients had a preoperative body mass index > 40 kg/m². A total of 206 patients were evaluated. All patients were given daily supplements of ferrous sulfate tablets for 2 wk following their operation. Hematological and metabolic indices were routinely evaluated following surgery. Patients were followed for a minimum of 86 wk.

RESULTS: There were 41 males and 165 females with an average age of 40.8 years. 21 patients (10.2%) developed post-operative anemia and 185 patients (89.8%) did not. Anemia was due to iron deficiency in all cases. The groups had similar demographics, surgical procedure and co-morbidities. Menstruation (P = 0.02) and peptic ulcer disease (P = 0.01) were risk factors for the development of post-operative anemia.

CONCLUSION: Iron deficiency anemia is frequent. RYGB surgery compounds occult blood loss. Increased ferrous sulfate supplementation may prevent iron depletion in populations at increased risk.

The bariatric surgery patient: a growing role for registered dietitians

Between 1998 and 2004, the total number of bariatric procedures increased almost 10-fold, from 13,386 procedures in 1998 to 121,055 in 2004. Current estimates suggest the number of bariatric operations will exceed 220,000 in 2010. Bariatric surgery encompasses several surgical techniques classified as restrictive or malabsorptive, based on the main mechanism of weight loss. Clinical studies and meta-analyses show that bariatric surgery decreases morbidity and mortality when compared with nonsurgical treatments. A successful long-term outcome of bariatric surgery is dependent on the patient's commitment to a lifetime of dietary and lifestyle changes. The registered dietitian (RD) is an important member of the bariatric team and provides critical instructions to help patients adhere to the dietary changes consistent with surgery. Referencing current literature, this article outlines the indications, contraindications, and types of bariatric surgery. The role of the RD for preoperative and postoperative nutrition assessment and medical nutrition therapy is highlighted. Management of long-term nutrition issues is also reviewed. The current recommendations include a multivitamin/mineral supplement plus vitamin B-12, calcium, vitamin D-3, iron, and folic acid. Given the increasing prevalence of obesity and bariatric surgery procedures, caring for patients who have undergone surgery will be an expanding role for the RD. Close postoperative follow-up and careful monitoring will improve the odds for successful surgical outcomes, and RDs play a very important part in this process.

Past, present, and future: Critical analysis of use of gastric bands in obese patients

Adjustable gastric banding (AGB) is quickly becoming the most popular bariatric operation performed in the United States and Canada. Patients are particularly fond of the simplicity of the tool, the relatively low morbidity of the surgery, the quick recovery, and overall results. The gastric band has evolved over its 35-year history into a very successful adjustable tool used to restrict food consumption and limit caloric intake. The percent of excessive weight loss after banding can range from 30%-60% and depends on the time out from surgery. Along with weight loss, there is good resolution of the co-morbid conditions that are associated with excess weight and improvements in quality of life demonstrated after banding. Nutrition and follow up are extremely important after banding to ensure good compliance and adequate weight loss. Failure to follow the postoperative diet, exercise regiment, or mechanical failure of the band can lead to failure to lose adequate weight. While there are particular early and late complications associated with this surgery, the safety profile of the AGB is very appealing when compared to other bariatric operations. As we continue to reduce the morbidity of the procedure, the simple adjustable band concept has a lot of potential to remain a primary technique of maintaining long term weight loss. In conclusion, AGB has and continues to play an important role in the treatment of morbid obesity. It offers reasonably good weight loss results with very little morbidity, and the future of the adjustable band is bright.

Nutritional deficiencies in obesity and after bariatric surgery

The presence of nutritional deficiencies in overweight and obesity may seem paradoxical in light of excess caloric intake, but several micronutrient deficiencies appear to be higher in prevalence in overweight and obese adults and children. Causes are multifactorial and include decreased consumption of fruits and vegetables, increased intake of high-calorie, but nutritionally poor-quality foods, and increased adiposity, which may influence the storage and availability of some nutrients. As the obesity epidemic continues unabated and the popularity of bariatric surgery rises for severely obese adults and adolescents, medical practitioners must be aware of pre-existing nutritional deficiencies in overweight and obese patients and appropriately recognize and treat common and rare nutritional deficiencies that may arise or worsen following bariatric surgery. This article reviews current knowledge of nutritional deficits in obese and overweight individuals and those that commonly present after bariatric surgery and summarizes current recommendations for screening and supplementation.

Vitamin status after bariatric surgery: a randomized study of gastric bypass and duodenal switch

BACKGROUND

Bariatric surgery is widely performed to induce weight loss.

OBJECTIVE

The objective was to examine changes in vitamin status after 2 bariatric surgical techniques.

DESIGN

A randomized controlled trial was conducted in 2 Scandinavian hospitals. The subjects were 60 superobese patients [body mass index (BMI; in kg/m(2)): 50-60]. The surgical interventions were either laparoscopic Roux-en-Y gastric bypass or laparoscopic biliopancreatic diversion with duodenal switch. All patients received multivitamins, iron, calcium, and vitamin D supplements. Gastric bypass patients also received a vitamin B-12 substitute. The patients were examined before surgery and 6 wk, 6 mo, and 1 y after surgery.

RESULTS

Of 60 surgically treated patients, 59 completed the follow-up. After surgery, duodenal switch patients had lower mean vitamin A and 25-hydroxyvitamin D concentrations and a steeper decline in thiamine concentrations than did the gastric bypass patients. Other vitamins (riboflavin, vitamin B-6, vitamin C, and vitamin E adjusted for serum lipids) did not change differently in the surgical groups, and concentrations were either stable or increased. Furthermore, duodenal switch patients had lower hemoglobin and total cholesterol concentrations and a lower BMI (mean reduction: 41% compared with 30%) than did gastric bypass patients 1 y after surgery. Additional dietary supplement use was more frequent among duodenal switch patients (55%) than among gastric bypass patients (26%).

CONCLUSIONS

Compared with gastric bypass, duodenal switch may be associated with a greater risk of vitamin A and D deficiencies in the first year after surgery and of thiamine deficiency in the initial months after surgery. Patients who undergo these 2 surgical interventions may require different monitoring and supplementation regimens in the first year after surgery. This trial was registered at ClinicalTrials.gov as NCT00327912.