Failure of preoperative resting energy expenditure in predicting weight loss after gastroplasty.

OBJECTIVE: To evaluate the predictive efficacy of preoperative resting energy expenditure (REE) on weight loss after vertical banded gastroplasty (VBG). When subjected to a gastric restriction procedure of similar extent, the patients with higher energy expenditure should experience a greater negative energy balance than those with lower-energy expenditure, and thus, lose more weight, thereby making REE a reliable predictor of weight loss after VBG. RESEARCH METHODS AND PROCEDURES: This was a prospective investigation after VBG, taking into account the relationship between preoperative REE values and the results at 1-year follow-up in terms of weight loss and success of the procedure. The correlations were evaluated by multiple and logistic regression analysis. RESULTS: The weight loss and the outcome at 1 year after VBG seemed to be completely independent of preoperative energy expenditure. DISCUSSION: These findings suggest that, despite gastric restriction, patients may voluntarily adjust their energy intake, and that the weight outcome after VBG is influenced more by behavioral and cognitive variables than by biological or surgical factors.

Glycemic control in diabetic patients after bariatric surgery.

BACKGROUND: Morbid obesity is associated with a high prevalence of diabetes mellitus, and weight loss is fundamental to improve glycemic control. The aim of the present study was to evaluate the impact of weight reduction during the late postoperative period (> or = 12 months) after gastric bypass on the glycemic control of diabetic patients. METHODS: Fasting glycemia (glucose oxidase) and glycohemoglobin A1c (enzymatic fluorescence, reference value: 4-6%) were determined before and after surgery. Results were compared by the Student t-test for paired samples (P <0.05). RESULTS: 23 women and 8 men with diabetes, with a mean follow-up of 27.2 months and a mean age of 42.5 years (30-68), were studied. Before surgery, mean +/- SD weight, BMI, excess weight, glycemia and glycohemoglobin were 135.9+/-11.6 kg, 51.8+/-6.4 kg/m2, 68.3+/-14.5 kg, 173+/-71.2 mg/dl, and 7.4+/-1.9%, respectively. After surgery, mean weight, BMI, excess weight, percent weight loss, percent excess weight loss, glycemia and glycohemoglobin were 89.7+/-8.8 kg, 35+/-4.5 kg/m2, 24.6+/-11.6 kg, 32.6%+/-1.8 (12.6-46.5%), 64.7+/-18.3%, 98+/-17.3 mg/dl (P <0.01), and 5.4+/-1.0% (P <0.05), respectively. Oral anti-diabetic drug and/or insulin treatment was discontinued in 89.2% of the patients. After surgery, 90.3% of the patients maintained glycohemoglobin A1c levels <7.0%. CONCLUSION: weight loss led to a significant and sustained improvement of glycemic control in these patients submitted to bariatric surgery.

Weight goals in a college-age population.

OBJECTIVE: Although a growing body of literature has found unrealistic weight loss goals to be common among older, primarily female, subjects, little is known about weight loss goals of younger adults. RESEARCH METHODS AND PROCEDURES: Three hundred seventy-nine college students had their height and weight taken and reported their "goal," "dream," "happy," "acceptable," and "disappointed" weights. A series of 2 (gender) x 2 (nonoverweight vs. overweight) ANOVAs were conducted with both absolute weight goals and percentage of weight loss needed to obtain those goals as dependent variables. RESULTS: When examined in terms of absolute weight goals, women generally had lower body mass index (BMI) goals than men, and nonoverweight participants had lower BMI goals than overweight participants. Surprisingly, most overweight participants would accept a weight loss that would still place them in the overweight BMI range. When examined in terms of percentage loss needed to reach those goals, only overweight women chose goal and dream weights that would require a loss greater than can be expected from nonsurgical weight-loss treatments, and all overweight participants chose happy and acceptable weights within 15% of current weight. DISCUSSION: Participants in this study had generally reasonable weight-loss goals, and even the most extreme weight loss goals were much more moderate than those found in previous studies. These results are surprising given the extreme social pressures for thinness facing young adults. Future studies should examine the variables that influence selection of goal weights and how goal weights affect actual dieting behavior.

Long-term effects of weight loss on pharmaceutical costs in obese subjects. A report from the SOS intervention study.

BACKGROUND: Although intentional weight reduction improves obesity-related comorbidities, the associations between weight reduction, medication and related costs are rarely studied. This study investigates the long-term effects of weight change on medication for diabetes and cardiovascular disease (CVD) in severely obese subjects. METHODS: In the intervention study Swedish Obese Subjects, 510 surgically and 455 conventionally treated obese patients have so far been followed for 6 y. Changes in the use and costs of medication were analyzed in relation to treatment and weight change. RESULTS: In comparison with controls, larger fraction of surgically treated patients discontinued the use of medication for CVD and diabetes at 2 and 6 y (risk ratios 0.56-0.77). Among subjects not initially on medication, surgery reduced the frequency of started treatments (risk ratios 0.08-0.80). Relative weight loss >or=10% was necessary to reduce costs of medication for CVD and diabetes among subjects with such treatment at baseline. To reduce initiation of new treatment against the two conditions, weight loss >or=15% was required. Over 6 y, the average annual cost for diabetes and CVD medication increased by 463 SEK (96%) in subjects with weight loss <5%, and decreased by 39 SEK(8%) in the weight loss group >or=15%. CONCLUSION: Long-term intentional weight loss is associated with reduced medication and medication costs for diabetes and CVD. The effects appear to be more marked among subjects who are initially on medication for these conditions, whereas greater weight reduction is needed to prevent new subjects from starting on medication.

Prevention or Surgical Treatment of Gallstones in Patients Undergoing Gastric Bypass Surgery for Obesity.

It is well known that obesity is a risk for gallstone formation and biliary sludge. Additionally, it has been clearly shown that rapid weight loss following bariatric surgery is a risk factor for cholesterol cholelithiasis. Multiple serious complications from gallstones such as cholecystitis, cholangitis, gallstone pancreatitis, and cholecystenteric fistulae may occur. Thus, it is necessary to employ medical or surgical methods to prevent or treat gallstones in this group. Therapy should be individualized. Although there is a high incidence of gallstones in this group, only a minority of individuals will develop symptomatic disease. When used in patients who are compliant, ursodeoxycholic acid therapy can be effective to prevent gallstone formation during rapid weight loss. The cost effectiveness of routine ursodeoxycholic acid therapy compared with the potential costs of complicated gallstone disease needs to be further investigated. Combined cholecystectomy with Roux-en-Y gastric bypass surgery is a safe and appropriate therapeutic option in those with preoperatively known gallstones, biliary sludge, and prior episodes of cholecystitis. However, routine cholecystectomy at the time of gastric bypass surgery is not warranted for all patients because of the increased time of operation and postoperative hospitalization, as well as all the potential complications after cholecystectomy. The approach of routine cholecystectomy in this setting subjects many patients to an unnecessary procedure because the majority will not develop symptoms or complications of gallstones. Furthermore, cholecystectomy is technically easier to perform after weight loss occurs.

Adenosine triphosphate infusion increases liver energy status in advanced lung cancer patients: an in vivo 31P magnetic resonance spectroscopy study.

We recently observed inhibition of weight loss in patients with advanced nonsmall-cell lung cancer after intravenous infusion of ATP. Because liver ATP levels were found to be decreased in lung cancer patients with weight loss, the present 31P magnetic resonance spectroscopy (MRS) study was aimed at investigating whether ATP infusion restores liver energy status in these patients. Nine patients with advanced nonsmall-cell lung cancer (stage IIIB/IV) were studied 1 week before (baseline) and at 22 to 24 hours of continuous ATP infusion (37-75 microg/kg/min). Localized hepatic 31P MR spectra (repetition time 15 seconds), obtained in the overnight-fasted state, were analyzed for ATP and P(i) content. Ten healthy subjects (without ATP infusion) served as control. Liver ATP levels in lung cancer patients increased from 8.8 +/- 0.7% (relative to total MR-detectable phosphate; mean +/- SE) at baseline to 12.2 +/- 0.9% during ATP infusion (P <.05), i.e., a level similar to that in healthy subjects (11.9 +/- 0.9%). The increase in ATP level during ATP infusion was most prominent in patients with > or = 5% weight loss (baseline: 7.9 +/- 0.7%, during ATP infusion: 12.8 +/- 1.0%, P < 0.01). In conclusion, ATP infusion restores hepatic energy levels in patients with advanced lung cancer, especially in weight-losing patients. These changes may contribute to the previously reported beneficial effects of ATP infusion on the nutritional status of lung cancer patients.

Effects of a 3-week integrated body weight reduction program on leptin levels and body composition in severe obese subjects.

The effects of short-term (3 weeks) integrated body weight reduction (BWR) program (including energy-restricted diet, aerobic and strength exercise (5 days/week), nutritional education and psychological counseling) on plasma leptin levels and body composition were investigated in 54 morbidly obese patients (38 females/16 males; mean BMI +/- SE: 41.8 +/- 0.1 kg/m2, range 35-58 kg/m2; mean age: 29.8 +/- 1.0 yr, age range: 18-46 yr). The BWR program induced a significant (p < 0.001) weight loss (BMI reduction: -4.8%) and a significant modification in body composition, consisting in a fat mass (FM) decrease (-7.0 +/- 0.4%, p < 0.001) with a concomitant fat-free (FFM) mass increase (1.8 +/- 0.3%, p < 0.001). On average, plasma leptin levels decreased significantly both in males (from 19.4 +/- 2.6 ng/ml to 11.6 +/- 1.3 ng/ml, p < 0.001) and in females (from 41.1 +/- 3.6 ng/ml to 29.9 +/- 3.0 ng/ml, p < 0.001). Both before and after weight loss, leptin levels were positively correlated (p < 0.001) with BMI and percent fat mass (FM) values. Weight changes after the BWR program were negatively correlated with baseline leptin concentrations both in absolute terms and expressed per unit FM. In conclusion, a short-term diet plus aerobic/strength training effectively induces body composition changes and reduces plasma leptin levels. Body FM reduction appears to be not the unique determinant of leptin levels regulation and the degree of leptin over-expression may negatively affect weight loss in morbidly obese patients.

Comparison of methods for assessing body composition changes during weight loss.

PURPOSE: Four cross-sectional studies have reported that percent body fat (%BF) measured by dual-energy x-ray absorptiometry (DXA) is significantly higher compared with values obtained with air displacement plethysmography (ADP) using the Bod Pod(R) in normal-weight individuals. This study was performed to confirm these findings in an overweight population and to assess whether DXA and ADP detected similar changes in body composition after moderate weight loss. METHODS: Twelve women (42 +/- 8 yr) and 10 men (40 +/- 11 yr) had their %BF, fat mass (FM), and fat-free mass (FFM) measured using DXA and ADP before and after an 8-wk weight-loss program involving moderate energy restriction and exercise. RESULTS: Body weight decreased significantly in women (-4.3 +/- 3.4 kg) and men (-4.7 +/- 3.1 kg). There were significant method (ADP vs DXA) and time (pre and post) effects but no method by time or gender interactions. Methods were significantly different in estimating %BF, FM, and FFM with ADP estimates of %BF and FM being lower and estimates of FFM higher than corresponding DXA values (P = 0.000). There were significant correlations accounting for a high degree of the shared variance between DXA and ADP (r = 0.98 to 0.99) for %BF, FM, and FFM and lower correlations for the changes in %BF (r = 0.66), FM (r = 0.86), and FFM (r = 0.34). In response to weight loss, the mean changes in %BF, FM, and FFM were not significantly different between methods (P > 0.05). CONCLUSION: Both DXA and ADP measure changes in body composition after small to moderate weight loss to the same extent and with similar sensitivity.