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Impact of rapid weight reduction on risk of cholelithiasis after bariatric surgery.
BACKGROUND: obesity alone and rapid weight loss induced by bariatric surgery are recognized risk factors for the development of cholelithiasis. The decision to perform prophylactic cholecystectomy at the time of bariatric operations remains controversial and at the surgeon's discretion. METHODS: From June 1998 to April 2001, 103 patients underwent Roux-en-Y gastric bypass (RYGBP) in Hospital das Clinicas/Unicamp (SP). 88 of these 103 patients had their preoperative ultrasonography of gallbladder recovered. 19 of these 88 patients showed gallstones before RYGBP, and the remaining 69 did not have ultrasonographic evidence of cholelithiasis. 36 of these 69 patients were followed with ultrasonography during the 12 postoperative months. They were divided into 2 groups: those who formed gallstones (n=19) and those who did not (n=17), to evaluate the importance of sex, age, preoperative BMI, preoperative excess weight and postoperative percent excess weight loss as risk factors in the gallstone formation. RESULTS: Preoperative incidence of cholelithiasis in the 88 operated patients was 21.6% and postoperative incidence in the 36 patients followed by ultrasonograph was 52.8%. There was no statistical evidence that postoperative gallstone formation is associated significantly with the variables studied. CONCLUSION: This study confirms the high correlation between morbid obesity, rapid weight loss and gallbladder disease. Predictive risk factors for gallstone formation were not found.
Recursive partitioning analysis of pretreatment variables of 416 patients with locoregional esophageal cancer treated with definitive concomitant chemoradiotherapy on Intergroup and Radiation Therapy Oncology Group trials.
PURPOSE: To analyze the relative contributions of uniformly collected pretreatment patient- and tumor-related variables to survival and to identify the terminal nodes via recursive partitioning analysis (RPA) that could be used as a stratification variable for future Phase III trials. METHODS AND MATERIALS: From two Intergroup trials (85-01, n = 130; and 94-05, n = 218) and one Radiation Therapy Oncology Group trial (92-07, n = 68), we identified 416 patients who were treated with definitive concomitant cisplatin and 5-FU-based chemoradiotherapy and analyzed their data for survival by RPA to define prognostic classes. The following pretreatment factors were evaluated: histologic type, age, weight loss, Karnofsky performance status, gender, race, T stage, tumor location, tumor size, N stage, and degree of dysphagia. The entire data set was considered as the initial node. The criterion for split points was the smallest p value less than unadjusted 0.05. RESULTS: Of the 416 patients, 336 (81%) were dead at the time of the analysis. The RPA identified only one significant split: pretreatment weight loss in the prior 6 months of <10% vs. > or =10%. After adjusting for multiple comparisons, no other split approached statistical significance. CONCLUSION: Unlike our experience with malignant glioma, brain metastases, and locally advanced non-small-cell lung cancer, RPA failed to identify novel prognostic information that could be incorporated into the stratification scheme of future chemoradiotherapy trials for esophageal cancer. Furthermore, our analysis validated the percentage of weight loss as a stratification variable for esophageal cancer.
Weight requirements for return of menstruations in teenage girls with eating disorders, weight loss and secondary amenorrhoea.
AIM: To investigate the weight requirements for return of menstruation in teenage girls with eating disorders (ED), weight loss and secondary amenorrhoea. METHODS: Growth charts from the school health services and measurements of weight and stature at assessment and during follow-up were obtained for 127 girls with ED, secondary amenorrhoea and subsequent return of menstruation. Measurements were used to estimate weight and body mass index (BMI) before puberty, at menarche, at the highest weight prior to the onset of the ED, at the last menstruation preceding amenorrhoea, at the lowest weight during treatment, and at return of menstruation. RESULTS: Before onset of the ED, the girls were taller, heavier and less lean than the population average as evidenced by standard deviation scores (SDS) for weight, height and BMI above zero. weight loss started from an average weight of 58.9 +/- 9.8 kg (mean +/- SD), a last menstruation occurred at 51.5 +/- 6.9 kg, the lowest weight during treatment was 45.6 +/- 7.0 kg and menstruation returned at 52.9 +/- 6.0 kg. Return of menstruation occurred within a wide weight range. However, if weight at return of menstruation was expressed in SDS, it could be predicted by a linear regression on weight SDS at loss of menstruation (r2 = 0.76; p < 0.001). CONCLUSIONS: The weight level required for return of menstruation is highly individual but can be predicted by the weight at which menstruations cease. In the treatment of ED, there is a need for such individual weight targets--a target based on the population weight for height and/or age may be too generalized and too low.
The effect of rate of weight loss on erythrocyte glutathione concentration and synthesis in healthy obese men.
Obesity is commonly associated with a high incidence and prevalence of dyslipidaemia, cardiovascular disease and Type II diabetes. Interestingly, studies have also reported decreased antioxidant levels in obese subjects. This may constitute an independent risk factor in the pathogenesis of coronary artery disease as obese subjects would have a decreased capacity to prevent the oxidative modification of low-density lipoproteins, which is a mechanism suggested as central to the development of atherogenesis. As part of a study to investigate responses to weight loss, we have assessed the effects on GSH status of a decrease in body mass of 5%, either after 6 days of complete starvation or 11 days of a very low calorie diet (2.55 MJ/day). There were significant differences between the two groups in the synthesis rate of erythrocyte GSH in response to weight loss. Both the fractional and the erythrocyte synthesis rate of GSH decreased significantly (P<0.01) in the starvation group by 22% and 16% respectively. In contrast, no change in synthesis rates was observed in the very low calorie diet group (P>0.05). Total erythrocyte concentration of GSH was unaffected by the weight loss within both groups. These results suggest that erythrocyte GSH synthesis is depressed in response to a very rapid weight loss induced by fasting. An acute reduction in GSH synthesis in response to a rapid weight loss may constitute a risk factor during periods of increased GSH demands.
Weight and BMI over 6 years in Korean children: relationships to body image and weight loss efforts.
OBJECTIVE: To investigate the relationships among longitudinal weight status, body dissatisfaction, and attitude to weight loss among Korean children from the age of 7-8 to 13-14 years old. RESEARCH METHODS AND PROCEDURES: 351 Korean school children's heights and weights were measured at the ages of 7-8 and 13-14 years old; at the age of 13-14, they completed a questionnaire about body dissatisfaction and weight loss efforts. RESULTS: At the age of 7-8, 15.7% of children were overweight by International obesity Task Force standards, as compared with 26.2% at the age of 13-14. Of the 55 7- to 8-year-old overweight children, 85.5% were still overweight at the age of 13-14 years old. Greater concerns about body image and stronger desires to be thinner were observed among stable overweight children and among those in whom there had been a rapid increase in BMI over the 6-year study period. Girls favored thinner shapes than did boys, regardless of their weight status or BMI changes. In girls, the level of body dissatisfaction was related only to weight loss desire, regardless of weight status or changes in BMI. In boys, however, weight loss desire was related only to weight loss attempts and was independent of weight status, BMI changes, and level of body dissatisfaction. DISCUSSION: Regardless of weight status, changes in BMI should be considered when dealing with body dissatisfaction and attitudes to weight loss in children.
Nutritional deterioration in cancer: the role of disease and diet.
AIMS: Under-nutrition is a major source of morbidity and mortality in cancer patients. This prospective, cross-sectional study aimed to evaluate the relative contributions of cancer staging, duration and diet on patients' nutritional deterioration. MATERIALS AND METHODS: We included 205 consecutive patients (133 men and 72 women) with head and neck, gastro-oesophageal, colon and rectum cancer, age 53 +/- 12 (33-86) years, referred for radiotherapy (primary, adjunctive to surgery, combined with chemotherapy or with palliative intent). We registered clinical variables, nutritional status (percentage of weight loss, Patient-Generated Subjective Global Assessment and body mass index), nutritional requirements, usual diet intake (diet history) and current intake (24-h recall). RESULTS: In stage III and IV, we observed a significant decrease of usual and current energy and protein intake (P=0.002), which were not observed in stage I and II. Reduction in nutritional intake was influenced by disease duration (P=0.04), but when the latter was evaluated in a multivariate analysis, current dietary intake was associated only with staging (P=0.004), thus disclosing a distinct pattern of nutritional intake between stages and diagnosis. Using a general linear model, advanced staging showed the most significant association with nutritional depletion (P=0.0001). We also found significant associations for tumour location (P=0.001), disease duration (P=0.002), nutritional intake (P=0.003) and previous surgery or chemotherapy (P=0.02). Percentage weight loss showed a consistently superior performance with regard to clinical variables and ability to detect mild to extreme nutritional changes. Patient-Generated Subjective Global Assessment had a very high sensitivity and specificity, and a strong capacity for detecting patients at nutritional risk compared with body mass index. CONCLUSIONS: Nutritional depletion is multifactorial, dependent mainly on the tumour burden of the host. Percentage weight loss is a sensitive and specific tool that can screen and identify malnutrition effectively. Its joint use with Patient-Generated Subjective Global Assessment, which establishes boundaries for nutritional therapy, will optimise the efficacy of nutritional assessment and support in cancer patients.
Relationship between sympathetic reactivity and body weight loss in morbidly obese subjects.
OBJECTIVE: To investigate the possible role of peripheral sympathetic activity in gastric bypass-induced body weight loss. SUBJECTS AND METHODS: In 42 morbidly obese patients (sex: 36 f/6 m; BMI: 46.0+/-0.7 kg/m(2)) undergoing a gastric bypass, the skin vasoconstrictor reflex in answer to a deep inspiration was measured by laser Doppler fluximetry. The extent of vasoconstriction, measured at the second finger of the left hand, was expressed as percent reduction of the basal blood flux (% vasoconstriction). Insulin sensitivity was assessed before surgery in a subset of patients (n=11), by the method of euglycemic, hyperinsulinemic clamp. Body weight and composition were evaluated before, and 3, 6 and 12 months after surgery. At the same time points, energy intake (kJ/day) was evaluated by means of both food record diary and alimentary anamnesis. RESULTS: The % vasoconstriction, which was significantly (P=0.01) greater in normoglycemic subjects than in diabetic ones, was also significantly (P=0.03) related to the extent of insulin sensitivity measured during the euglycemic clamp.The % vasoconstriction showed a significant (P>0.0001), positive correlation with weight reduction obtained between the 6th and 12th months following surgery; as a consequence, % vasoconstriction was significantly (P=0.0004) related to the overall body weight loss achieved during the year following the operation. These correlations remained significant in multiple regression analysis with adjustment for age, initial body weight, plasma glucose and insulin (P=0.0007 and 0.006, respectively). The % vasoconstriction was also significantly (P=0.0006), negatively related to energy intake measured 12 months after surgery. CONCLUSIONS: In conditions of stable body weight, the sympathetic nervous system (SNS) reactivity is influenced by the degree of insulin resistance. A high capacity to activate the SNS, measured before surgery, is associated with both a larger gastric bypass-induced weight loss and a lower energy intake, at the phase of weight stabilization.
Weight Loss regulates inflammation-related genes in white adipose tissue of obese subjects.
Adipose tissue produces inflammation and immunity molecules suspected to be involved in obesity-related complications. The pattern of expression and the nutritional regulation of these molecules in humans are poorly understood. We analyzed the gene expression profiles of subcutaneous white adipose tissue from 29 obese subjects during very low calorie diet (VLCD) using cDNA microarray and reverse transcription quantitative PCR. The patterns of expression were compared with that of 17 non-obese subjects. We determined whether the regulated genes were expressed in adipocytes or stromavascular fraction cells. Gene expression profiling identified 100 inflammation-related transcripts that are regulated in obese individuals when eating a 28 day VLCD but not a 2 day VLCD. Cluster analysis showed that the pattern of gene expression in obese subjects after 28 day VLCD was closer to the profile of lean subjects than to the pattern of obese subjects before VLCD. weight loss improves the inflammatory profile of obese subjects through a decrease of proinflammatory factors and an increase of anti-inflammatory molecules. The genes are expressed mostly in the stromavascular fraction of adipose tissue, which is shown to contain numerous macrophages. The beneficial effect of weight loss on obesity-related complications may be associated with the modification of the inflammatory profile in adipose tissue.
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