Anna Laurenius

Gut hormones as mediators of appetite and weight loss after roux-en-Y gastric bypass

Objective:To evaluate the physiologic importance of the satiety gut hormones. Background:Controversy surrounds the physiologic role of gut hormones in the control of appetite. Bariatric surgery remains the most effective treatment option for obesity, and gut hormones are implicated in the reduction of appetite and weight after Roux-en-Y gastric bypass. Methods:We correlated peptide YY (PYY) and glucagon-like peptide 1 (GLP-1) changes within the first week after gastric bypass with changes in appetite. We also evaluated the gut hormone responses of patients with good or poor weight loss after gastric bypass. Finally, we inhibited the gut hormone responses in gastric bypass patients and then evaluated appetite and food intake. Results:Postprandial PYY and GLP-1 profiles start rising as early as 2 days after gastric bypass (P < 0.05). Changes in appetite are evident within days after gastric bypass surgery (P < 0.05), and unlike other operations, the reduced appetite continues. However, in patients with poor weight loss after gastric bypass associated with increased appetite, the postprandial PYY and GLP-1 responses are attenuated compared with patients with good weight loss (P < 0.05). Inhibiting gut hormone responses, including PYY and GLP-1 after gastric bypass, results in return of appetite and increased food intake (P < 0.05). Conclusion:The attenuated appetite after gastric bypass is associated with elevated PYY and GLP-1 concentrations, and appetite returns when the release of gut hormones is inhibited. The results suggest a role for gut hormones in the mechanism of weight loss after gastric bypass and may have implications for the treatment of obesity.

Changes in eating behaviour and meal pattern following Roux-en-Y gastric bypass

Background:Little is known about eating behaviour and meal pattern subsequent to Roux-en-Y gastric bypass (RYGB), knowledge important for the nutritional care process. The objective of the study was to obtain basic information of how meal size, eating rate, meal frequency and eating behaviour change upon the RYGB surgery.Materials and methods:Voluntary chosen meal size and eating rate were measured in a longitudinal, within subject, cohort study of 43 patients, 31 women and 12 men, age 42.6 (s.d. 9.7) years, body mass index (BMI) 44.5 (4.9) kg m−2. Thirty-one non-obese subjects, 37.8 (13.6) years, BMI 23.7 (2.7) kg m−2 served as a reference group. All subjects completed a meal pattern questionnaire and the Three-Factor Eating Questionnaire (TFEQ-R21).Results:Six weeks postoperatively meal size was 42% of the preoperative meal size, (P<0.001). After 1 and 2 years, meal size increased but was still lower than preoperative size 57% (P<0.001) and 66% (P<0.001), respectively. Mean meal duration was constant before and after surgery. Mean eating rate measured as amount consumed food per minute was 45% of preoperative eating rate 6 weeks postoperatively (P<0.001). After 1 and 2 years, eating rate increased to 65% (P<0.001) and 72% (P<0.001), respectively, of preoperative rate. Number of meals per day increased from 4.9 (95% confidence interval, 4.4,5.4) preoperatively to 6 weeks: 5.2 (4.9,5.6), (not significant), 1 year 5.8 (5.5,6.1), (P=0.003), and 2 years 5.4 (5.1,5.7), (not significant). Emotional and uncontrolled eating were significantly decreased postoperatively, (both P<0.001 at all-time points), while cognitive restraint was only transiently increased 6 weeks postoperatively (P=0.011).Conclusions:Subsequent to RYGB, patients display markedly changed eating behaviour and meal patterns, which may lead to sustained weight loss.

Early Complications After Laparoscopic Gastric Bypass Surgery : Results From the Scandinavian Obesity Surgery Registry

Objective:To identify risk factors for serious and specific early complications of laparoscopic gastric bypass surgery using a large national cohort of patients. Background:Bariatric procedures are among the most common surgical procedures today. There is, however, still a need to identify preoperative and intraoperative risk factors for serious complications. Methods:From the Scandinavian Obesity Surgery Registry database, we identified 26,173 patients undergoing primary laparoscopic gastric bypass operation for morbid obesity between May 1, 2007, and September 30, 2012. Follow-up on day 30 was 95.7%. Preoperative data and data from the operation were analyzed against serious postoperative complications and specific complications. Results:The overall risk of serious postoperative complications was 3.4%. Age (adjusted P = 0.028), other additional operation [odds ratio (OR) = 1.50; confidence interval (CI): 1.04–2.18], intraoperative adverse event (OR = 2.63; 1.89–3.66), and conversion to open surgery (OR = 4.12; CI: 2.47–6.89) were all risk factors for serious postoperative complications. Annual hospital volume affected the rate of serious postoperative complications. If the hospital was in a learning curve at the time of the operation, the risk for serious postoperative complications was higher (OR = 1.45; CI: 1.22–1.71). The 90-day mortality rate was 0.04%. Conclusions:Intraoperative adverse events and conversion to open surgery are the strongest risk factors for serious complications after laparoscopic gastric bypass surgery. Annual operative volume and total institutional experience are important for the outcome. Patient related factors, in particular age, also increased the risk but to a lesser extent.

Decreased energy density and changes in food selection following Roux-en-Y gastric bypass.

Background/Objectives:The main objective was to test the hypothesis that dietary energy density (DED) decreases after Roux-en-Y gastric bypass (gastric bypass).Subjects/Methods:A total of 43 patients (31 women and 12 men) aged 43 (s.d. 10) years, with body mass index (BMI) 44.3 kg/m2 (4.9), were assessed preoperatively at 6 weeks and 1 and 2 years after gastric bypass. Self-reported energy intake (EI), food weight (FW) and food choice were assessed using a dietary questionnaire. DED was calculated by dividing EI by FW (kcal/g). Number of dropouts was 4 of 203 visits.Results:Percent weight loss (%WL) was 13.5% at 6 weeks, 30.7% at 1 year and 31.8% at 2 years post surgery (P<0.001 for all). EI decreased from 2990 to 1774, 2131 and 2425 kcal after 6 weeks and 1 and 2 years postoperatively, respectively (P<0.001 at all time points). FW changed from 2844 to 1870 g/day at 6 weeks (P<0.001) and 2416 g/day after 1 year (P<0.05), but was not significantly different from baseline 2 years postoperatively (2602 g/day, P=0.105). DED decreased from 1.07 to 0.78 kcal/g at 6 weeks (P<0.001) and 0.90 kcal/g (P<0.001) and 0.96 kcal/g (P=0.001) after 1 and 2 years, respectively. All statistical comparisons were made from baseline. There was no correlation between changes in DED and %WL, neither after 1 year (r=−0.215; P=0.183) nor after 2 years (r=−0.046; P=0.775) post surgery.Conclusions:Besides substantial reduction in EI and large variation in FW, patients reported decreased DED over 2 years following gastric bypass. Despite lack of association between the reduction in DED and percentage weight loss, changes in food choice were overall nutritionally beneficial.

More symptoms but similar blood glucose curve after oral carbohydrate provocation in patients with a history of hypoglycemia-like symptoms compared to asymptomatic patients after Roux-en-Y gastric bypass

BACKGROUND Laparoscopic Roux-en-Y gastric bypass (LRYGB) is an effective treatment for obesity through altering several physiologic mechanisms. Some patients experience symptoms suggestive of hypglycemia after LRYGB, but whether these symptoms always are associated with low blood glucose are unclear. The objective of this study was to investigate the correlation between symptoms suggestive of hypglycemia, plasma glucose levels and gut hormones involved in glycemic control. METHODS Eight LRYGB patients with hypglycemia-like symptoms (SY) and 8 patients with no hypglycemia-like symptoms (ASY) ingested a liquid carbohydrate meal. Insulin, plasma-glucose, glucagon-like peptide 1 (GLP-1) and glucagon were measured intermittently 180 minutes postprandially. In addition, pulse rate, blood pressure and symptoms were assessed. RESULTS Plasma glucose at 120 min was lower in the ASY mean (95% CI) 2.4 (1.6,3.3) mmol/L (43.2 mg/dL) compared to the SY group 3.0 (3.1,4.6) mmol/L (54.6 mg/dL), (P = .050). The ASY group had larger reduction in plasma glucose than the SY group from pre- to 120 min postmeal -2.2 (-2.8,-1.7) mmol/L (-39.6 mg/dL) versus -1.1 (-1.7,-0.4) mmol/L (-19.8 mg/dL), (P = .011). The concentrations of insulin, GLP-1 and glucagon did not differ significantly between groups. Blood pressure was similar between groups, but the AUC for pulse rate was higher in the SY than ASY group 13009 (11148,14870) versus 11569 (10837,12300) beats/180 minutes, (P = .038). The SY group reported more symptoms than the ASY group, AUC for Sigstad scale 60 to 180 minutes was 970 (-274,1667) for SY versus 170 for ASY (-39,379), (P = .028). CONCLUSION Patients with a history of symptoms suggestive of hypglycemia after LRYGB neither demonstrated lower plasma glucose nor greater insulin response compared to asymptomatic patients in response to a liquid carbohydrate meal, but perceived more symptoms.

Substantial Decrease in Comorbidity 5 Years After Gastric Bypass: A Population-based Study From the Scandinavian Obesity Surgery Registry

Objective: To evaluate effect on comorbid disease and weight loss 5 years after Roux-en-Y gastric bypass (RYGB) surgery for morbid obesity in a large nationwide cohort. Background: The number patients having surgical procedures to treat obesity and obesity-related disease are increasing. Yet, population-based, long-term outcome studies are few. Methods: Data on 26,119 individuals [75.8% women, 41.0 years, and body mass index (BMI) 42.8 kg/m2] undergoing primary RYGB between May 1, 2007 and June 30, 2012, were collected from 2 Swedish quality registries: Scandinavian Obesity Surgery Registry and the Prescribed Drug Registry. Weight, remission of type 2 diabetes mellitus, hypertension, dyslipidemia, depression, and sleep apnea, and changes in corresponding laboratory data were studied. Five-year follow-up was 100% (9774 eligible individuals) for comorbid diseases. Results: BMI decreased from 42.8 ± 5.5 to 31.2 ± 5.5 kg/m2 at 5 years, corresponding to 27.7% reduction in total body weight. Prevalence of type 2 diabetes mellitus (15.5%–5.9%), hypertension (29.7%–19.5%), dyslipidemia (14.0%–6.8%), and sleep apnea (9.6%–2.6%) was reduced. Greater weight loss was a positive prognostic factor, whereas increasing age or BMI at baseline was a negative prognostic factor for remission. The use of antidepressants increased (24.1%–27.5%). Laboratory status was improved, for example, fasting glucose and glycated hemoglobin decreased from 6.1 to 5.4 mmol/mol and 41.8% to 37.7%, respectively. Conclusions: In this nationwide study, gastric bypass resulted in large improvements in obesity-related comorbid disease and sustained weight loss over a 5-year period. The increased use of antidepressants warrants further investigation.

Dumping symptoms is triggered by fat as well as carbohydrates in patients operated with Roux-en-Y gastric bypass

BACKGROUND Dumping syndrome after Roux-en-Y gastric bypass (RYGB) is traditionally associated with the consumption of refined carbohydrates, but the role of dietary fat is unclear. OBJECTIVES This study compares symptoms after consumption of a carbohydrate-rich or fat-rich beverage to determine perceived symptoms, glycemic control, and pulse rate. SETTING University hospital. METHODS We assessed perceived symptoms (Sigstads Dumping Index) and glycemic control (P-glucose and S-insulin) as well as autonomic nervous system activity (reflected by arterial pulse rate) after a standardized liquid meal test (440 kcal/300 mL carbohydrates [CARB] or fat [FAT]) in a randomized crossover blinded setting. Blood samples were drawn before and 1, 15, 30, and 60 minutes after finishing each meal and the area under the curve (AUC) was calculated. RESULTS Twelve patients 42±10 months after undergoing RYGB were studied. AUC differed between drinks for glucose (P = .003) and insulin (P = .005). Pulse rate increased more after CARB than after FAT (P = .01). AUC for perceived symptoms in the Sigstads Dumping Index were similar after meals (P = .79), yet the pattern of type of symptoms differed. CONCLUSION In patients with RYGB, a meal with predominant fat content resulted in as much perceived dumping symptoms as a carbohydrate-profiled meal. As expected, an increase in glucose and insulin levels were found only after carbohydrate intake and the pulse rise was more pronounced for carbohydrates than fat. Dietary counseling in patients undergoing RYGB should address dietary fat as well as traditional information about carbohydrates to avoid dumping symptoms.

Nordiske retningslinjer for oppfølging etter fedmekirurgi

INGMAR NÄSLUND Ingmar Näslund (f. 1947) er spesialist i kirurgi med fedmekirurgisk erfaring fra 1970-årene. Han er dosent ved Örebro Universitet, Sverige, og overlege ved Universitetssjukhuset i Örebro. Forfatter har fylt ut ICMJE-skjemaet og oppgir følgende interessekonflikter: Han har mottatt konsulentog forelesningshonorar fra Baricol Bariatrics, som produserer mineral-vitaminkombinasjoner spesifikt rettet mot pasienter som har gjennomgått fedmekirurgi.

Five-year changes in dietary intake and body composition in adolescents with severe obesity undergoing Laparoscopic Roux-en-Y Gastric Bypass surgery

BACKGROUND Information is scarce on long-term changes in energy intake (EI), dietary energy density (DED), and body composition in adolescents undergoing laparoscopic Roux-en-Y gastric bypass (RYGB). OBJECTIVES To investigate long-term changes in EI, DED, and body composition in adolescents after LRYGB. SETTING University hospitals, multicenter study, Sweden. METHODS Eighty-five adolescents (67% girls; mean ± standard deviation, age 16.0 ± 1.2 yr, body mass index 45.5 ± 6.1 kg/m2) were assessed preoperatively (baseline) and 1, 2, and 5 years after LRYGB with diet history interviews and dual-energy x-ray absorptiometry. Matched obese adolescent controls receiving nonsurgical treatment were assessed only at 5 years. RESULTS Weight decreased 31%, 33%, and 28% at 1, 2, and 5 years after LRYGB (P < .001) while controls gained 13% over 5 years (P < .001). Dietary assessments were completed in 98%, 93%, 87%, and 75% at baseline and 1, 2, and 5 years, respectively, and in 65% of controls. Baseline EI (2558 kcal/d), decreased by 34%, 22%, and 10% after 1, 2, and 5 years (P < .05). DED decreased at 1 year (P = .03). Macronutrient distribution was not different from controls at 5 years, but EI and DED were 31% and 14% lower (P < .015). Fat, fat-free, and muscle mass decreased through 5 years after LRYGB (P < .001). Boys preserved muscle mass more than girls (P < .01). Adequate protein intake was associated with preservation of muscle mass (P = .003). CONCLUSIONS In adolescents undergoing LRYGB EI remained 10% lower 5 years after surgery. Decreased EI and DED, rather than macronutrient distribution, are important factors in weight loss after surgery. Higher protein intake may facilitate preservation of muscle mass.