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The autonomic nervous system (ANS) and hypothalamic-pituitary-adrenal (HPA) axis are reported as activated in excess in the morbidly obese state and, therefore, changes after weight loss can be anticipated. The aim of this study was to investigate the impact of a massive (approximately 30%) weight reduction on the activation of the HPA axis and the ANS following bariatric surgery. Eight (7 women, 1 man) severely obese (125+/-12 kg; body mass index [BMI], 45+/-4 kg/m2) nondiabetic subjects, underwent a 3-hour hyperinsulinemic (1,034 pmol/kg/h) glucose clamp study at hypoglycemia of arterial B-glucose concentration of 3.4 mmol/L. Cognitive function was evaluated by a visuospatial computerized problem-solving test, the Perceptual Maze Test (PMT). The mean weight loss was 40+/-9 kg approximately 12 months postsurgery when their weight was stabilized (85+/-6 kg; BMI, 31+/-3 kg/m2), and insulin sensitivity improved to an average increase of 376%+/-250% (P<.01) of initial value. Before weight reduction, all patients demonstrated brisk peak responses in glucagon, epinephrine, pancreatic polypeptide (PP), norepinephrine, and cortisol, indicative of preserved or exaggerated activation of ANS and HPA axis. In the reduced-obese state, all these responses were attenuated and most markedly so for glucagon, which was totally abolished. In contrast, the growth hormone (GH) response was increased after weight reduction. The cognitive function was clearly modified by weight reduction both during normoglycemia and hypoglycemia and was changed preferentially to a speed-preferring strategy in the reduced-obese state compared with a more accuracy preferred problem-solving process of PMT test presurgery. These results demonstrate a reduction of the glucose counterregulatory hormonal responses, increased insulin sensitivity, and perturbed cognitive function after massive weight reduction. It may be speculated on if the increased insulin sensitivity and reduced counterregulation to hypoglycemia could predispose to low plasma glucose concentrations.

Background: The two main reasons for reoperation after vertical banded gastroplasty (VBG) in the treatment of obesity are staple-line disruption and stomal stenosis., Patients: Seven morbidly obese patients of mean (+/-SEM) body mass index (BMI) 43.7 +/- 1.9 kg/m2 treated with an adjustable vertical banded gastroplasty (AVBG)., Results: No complications of the band system were reported. Weight-loss [BMI at 2 years follow-up 33.9 +/- 6.9 kg/m2 (n = 5)] was equivalent to that seen after VBG with a fixed band. Two of the patients developed staple-line disruption at 18 and 24 months after surgery., Conclusion: AVBG allows adjustment of the stoma, but staple-line disruption was common in this small series. It is possible that an excessive filling of the band in order to achieve excess weight loss results in a high pressure in the upper pouch which increases the risk of staple-line disruption.

The aim of the present study was to study the interdigestive motor complex (MMC), distal small intestinal hormones, and gastric emptying in normal-weight and obese subjects before and after jejunoileal bypass (JIB). Therefore, fasting antroduodenal motility, gastric emptying, and RIA for motilin (MOT), neurotensin (NT), peptide YY (PYY), and glucagon-like peptide-1 (GLP-1) was performed in nine obese subjects before (BMI 42 +/- 4 kg/m2) and nine months after (BMI 31 +/- 4) JIB, and in two groups of nine age- and sex-matched controls (BMI 23 +/- 1 and 21 +/- 1). The rate of gastric emptying was faster in obese subjects and GLP-1 lower compared to normal-weight controls. After JIB, fewer phase III of the MMC were observed; fasting levels of PYY were elevated during the MMC; postprandial levels of NT, PYY, and GLP-1 were elevated; and gastric emptying was delayed. Our results suggest that there may be an association between an impaired GLP-1 response after food intake and obesity, and after JIB, PYY seems to regulate interdigestive motility while GLP-1 may regulate early gastric emptying.

Objective: Some studies have shown a more rapid gastric emptying in obese subjects. Six to twelve months after jejunoileal bypass (JIB) neurotensin (NT) and enteroglucagon have been shown to be elevated after food intake. These hormones, together with peptide YY (PYY) and glucagon-like peptide-1 (GLP-1) have been implicated in the reduction of upper gastrointestinal motility seen after infusion of nutrients into the ileum., Aim: To study if the postprandial gut hormone pattern and gastric emptying is altered 20 y after JIB., Subjects: Seven subjects operated with JIB a mean (s.d.) 20 +/- 3 y ago, with a BMI of 44 +/- 4 kg/m2 at the time of surgery and 31 +/- 4 at present. For comparison seven sex-matched non-operated obese controls (BMI 43 +/- 3) were studied., Methods: Serial blood samples were obtained every 10 min after intake of a 280 kcal meal. Radioimmunoassays for motilin, cholecystokinin (CCK), NT, PYY and GLP-1 were performed. Gastric emptying of a solid meal was studied using a radioactively labelled omelette (of 310 kcal) for 120 min)., Results: After JIB postprandial motilin, CCK, NT, PYY and GLP-1 were elevated compared to non-operated obese subjects. Similarly, basal levels of CCK, motilin, GLP-1 and PYY were elevated in the operated group. No difference was observed in the rate of gastric emptying between the two groups., Conclusion: Both fasting and postprandial gut hormone levels are elevated 20 y after JIB. The impact of long-term rapid stimulation of the ileum and subsequent raised gut hormone levels on gastric emptying is not clear.

Objective: To present our experience with a group of obese patients treated by vertical banded gastroplasty., Design: Open prospective study., Setting: Teaching hospital, Sweden., Subjects: 198 Morbidly obese patients operated on between 1986 and April 1994., Interventions: Modified Mason vertical banded gastroplasty., Main Outcome Measures: Weight loss, mortality, early and late morbidity, and reoperation., Results: The mean (SEM) age was 40 (0.7) and 149 of the 198 were women (75%). 22 Patients (11%) were lost to follow-up. Five patients died (3%), one soon after operation. Mean (SEM) body mass index (BMI) was 44.4 (0.5) preoperatively and this decreased to 32.6 (0.6) after four years (n = 99) and 33.8 (1.3) after seven years (n = 20). 21 patients developed 24 early postoperative complications, and 31 patients were reoperated on 41 times for late complications., Conclusion: All patients lost weight after vertical banded gastroplasty, and their weight continued to decrease during a seven-year follow-up. This was somewhat offset by the high rate of reoperations required.

Obesity is often associated with an increased hepatic secretion rate of cholesterol and saturated gallbladder bile. In order to evaluate the role of hepatic esterification of cholesterol in this phenomenon, we assayed the activity of acyl CoA:cholesterol acyl transferase (ACAT), which catalyzes the esterification of cholesterol, in liver microsomes obtained from 19 morbidly obese patients without gallstones undergoing vertical banded gastroplasty. Gallbladder bile was obtained and analyzed for lipid composition, cholesterol saturation, nucleation time, and occurrence of cholesterol crystals. Fourteen non-obese gallstone-free subjects undergoing cholecystectomy because of suspected polyp or adenomyoma in the gallbladder served as controls. The hepatic content of esterified cholesterol was increased by about 70% in the obese patients (P < 0.05). Still, the mean levels of the ACAT activity were equal in the obese and non-obese patient groups (11 +/- 1 and 11 +/- 2 pmol/min per mg protein, respectively). When exogenous cholesterol was added to the assay system, the activity was increased markedly in both groups. The ACAT activity was higher in obese patients with steatosis of the liver compared with those displaying normal liver morphology (12 +/- 1 vs 8 +/- 1 pmol/min per mg, P < 0.05). Obese patients did not have significantly more saturated gallbladder bile than the non-obese controls (84 +/- 7 and 77 +/- 8%, respectively). They had a normal nucleation time and their gallbladder bile did not contain any cholesterol crystals. We conclude that obese patients without gallstones usually have a normal esterification rate of cholesterol in the liver. Steatosis of the liver was associated with increased ACAT activity.(ABSTRACT TRUNCATED AT 250 WORDS)

The influence of excessive weight loss, with decreased muscle mass, on pulmonary function was evaluated in 16 obese patients without clinical evidence of respiratory disease. Weight loss was induced with vertical banded gastroplasty. Six nonobese age-matched patients undergoing elective cholecystectomy acted as controls. Preoperative values for static and dynamic lung function variables and for pulmonary gas distribution and respiratory muscle strength were compared with postoperative values after approximately 10% and 18% weight reduction. Before gastroplasty the dominant abnormality of respiratory function was slight restrictiveness, with reduced lung volumes. Body weight and lean body mass decreased significantly during the study period, and respiratory muscle strength was significantly reduced after 10% weight loss. Lung function tests nevertheless showed significant increase of vital capacity, functional residual capacity, total lung capacity and maximal voluntary ventilation. No correlation was found between the reduction of respiratory muscle strength and that of lean body mass. The controls did not diminish the body weight after surgery and the lung volumes and respiratory muscle strength was not changed.

A 35-year-old woman became pregnant 15 months after gastric banding, during which time she lost 55 kg in weight. During the third trimester, severe vomiting was noted and she lost a further 6 kg. Ultrasound examination showed oligohydramnions and fetal growth retardation of 38%. Enteral nutrition was given until delivery and ultrasound verified normalization of the oligohydramnions and weight gain for the fetus. The woman was delivered by cesarean section of a female infant with birthweight 2,470 g. It is concluded that special care must be taken with regard to the nutritional status of pregnant women who have previously been operated on with gastric procedures for obesity, in order to diminish the risk of fetal growth retardation. Ultrasound examinations should be performed on wide indications and enteral nutrition must start immediately once fetal growth retardation is discovered.

Impaired glucose tolerance and hyperinsulinaemia are common features of obesity. Since oxytocin has been shown to influence glucose metabolism and insulin secretion, the objective of the present study was to investigate whether the plasma level of oxytocin is elevated in obese subjects and if so, whether it is affected by weight reduction following gastric banding. Repeated blood samples were collected in connection with ingestion of a liquid test meal from subjects weighing about 130 kg. Normal weight subjects were tested likewise. Further tests were performed on obese subjects 6 months after operation with gastric banding and a subsequent weight reduction of about 30 kg. Plasma levels of oxytocin were measured by radioimmunoassay. It was found that plasma levels of oxytocin were 4-fold higher in the obese subjects when compared to the control subjects. Analysis with high performance liquid chromatography demonstrated that the oxytocin-like material, as determined by radioimmunoassay, in extracted plasma from one obese subject coeluted with synthetic oxytocin standard. Ingestion of a test meal did not seem to influence oxytocin levels. The mean oxytocin level was equally elevated in male and female obese subjects. Following operation oxytocin levels decreased significantly, but were still significantly higher than in the control subjects. The mechanism behind the hyperoxytocinaemia and possible consequence of it remain obscure.

In view of previous reports that the activity of the Mg(++)-dependent phosphatidic acid phosphatase in adipose tissues of rat and mouse is elevated in obesity, we attempted to assay this activity in biopsies of human omental adipose tissue obtained from normal-weight and morbidly obese subjects in connection with operations. The major portion of the phosphatidic acid phosphatase activity was found in the cytosol, and the small amount found in the microsomal fraction was too low for accurate measurement. It was not possible to assay the activity in the crude cytosol. After precipitation with ammonium sulfate, however, the enzyme activity was linear with both the incubation time and the concentration of enzyme. It was not possible to obtain substrate saturation of the enzyme under the conditions employed. When assayed in the presence of a high concentration of substrate (0.6 mmol/l) the activity obtained in normal-weight patients, 7.8 +/- 2.4 nmol/mg protein/min (n = 10), was not significantly different from that in morbidly obese patients, 5.6 +/- 0.8 nmol/mg protein/min (n = 10). There was no relation between the size of adipose cells and phosphatidic acid phosphatase activity. Furthermore, there was no apparent relation between phosphatidic acid phosphatase activity in omental adipose tissue and that in the liver. The findings suggest that the increased biosynthesis of triglycerides in human obesity is not associated with an increased capacity of the soluble phosphatidic acid phosphatase in adipose tissue.

The gastric acid secretion was studied in 17 extremely obese patients after injection of synthetic gastrin (Peptavlon). The mean basal acid output (BAO) and the peak acid output (PAO) were both within normal range. Positive correlation was found between PAO and body weight. Gastric banding was performed as treatment of the obesity, and the gastric acid secretion was studied in the proximal and the distal pouch after a mean postoperative interval of 8 (range 4-20) weeks. BAO was similar after banding, but PAO was significantly decreased (from 26.3 +/- 3.6 to 16.2 +/- 2.2 mmol/h). PAO and BAO were almost identical in the two pouches, despite great difference in their size.

Seventy-two patients who underwent gastric banding for extreme obesity were followed for a mean of 30 (range 12-54) months. The mean weight loss after 1 year was 41 kg. About two-thirds of the patients had only minor complaints postoperatively, but the others had complications, some of which were serious. Two patients died. Complications related to the banding technique necessitated 33 reoperations in 22 patients. The most common cause of reoperation/complication was functional stenosis of the upper pouch outlet, but only 3 of 22 revisional operations were successful. Reduction in band tension resulted in fewer reoperations but also less weight loss. The incidence of complications and the poor outcome of revision indicate that gastric banding should still be regarded as an experimental operation. Peroperative measurement of all technical details and careful and frequent follow-up examination are necessary in the search for an optimal technical procedure, giving good weight loss with a minimum of complications.

The postprandial secretion of insulin, gastrin and somatostatin was studied in 23 extremely obese subjects and nine normal-weight controls after a liquid test meal. Apart from a significantly higher insulin level in the obese group, no significant intergroup difference was found. The effect of weight loss on the same hormones was studied in 18 patients 6 months after gastric banding. The mean weight loss during this period was 33 +/- 2.1 (SEM) kg. There was significant decrease in postprandial insulin secretion after gastric banding, but neither gastrin nor somatostatin levels were altered.

Small size of the upper pouch has been considered mandatory for good weight loss after different gastric operations for extreme obesity. In most published series the estimates of upper pouch size seem to have been subjective. The present report concerns gastric banding in 18 patients, with standardized objective measurement of the upper pouch made after subjective estimation independently by two bariatrically trained surgeons. The subjective determination resulted in statistically significant underestimation compared with the objective procedure. For adequate evaluation of the surgical method, therefore, it is important to measure the pouch size objectively.