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Obesity treatment: examining the premises.
Five basic premises underlie the recommendation that obese persons should lose weight: (1) obesity is physically unhealthy; (2) in obese persons, weight loss improves physical health; (3) long-term weight loss is possible; (4) the benefits of weight loss exceed the costs; and (5) weight loss is superior to or can add incrementally to the effects of alternative methods of improving the health and happiness of obese persons. Although the data are occasionally ambiguous, they generally support these premises. obesity apparently causes increased morbidity and decreased longevity, even after controlling for many plausible confounding factors. Clinical studies consistently show that weight loss reduces morbidity. No adequate data exist on which to evaluate the effects of weight loss on mortality among obese persons. Additional data are needed, but long-term weight loss seems possible, although such losses remain difficult to maintain. A crude estimate is that about 20% of obese persons who attempt to lose weight can achieve and maintain a clinically meaningful weight loss. The short-term health and psychologic costs of gradual weight loss are minor, manageable, and easily surpassed by the short-term health and psychologic benefits. Long-term effects of weight loss on mortality are difficult to judge, and further research is needed. weight loss can add incrementally to the effects of alternative methods to improve health and happiness among obese persons. Thus, these "alternatives" are better termed "complementary approaches," and their use need not preclude attempts at weight loss. Finally, we provide several guidelines to help practitioners assist obese persons in making reasonable informed decisions about weight loss.
Sibutramine ( Meridia ) treatment in obesity: initial eating behaviour in relation to weight loss results and changes in mood.
The aim of the study was to study the role of initial eating behaviour for subsequent weight loss in treatment with Sibutramine ( Meridia ) (Reductil, Meridia) an anti-obesity drug enhancing satiety, and also to assess changes in mood during the treatment. The participants were 36 obese patients with a mean BMI of 39 kg m(-2). Eating behaviour was assessed with the three factor eating questionnaire (TFEQ), and depressive features with the comprehensive psychopathological rating scale (CPRS). Sibutramine ( Meridia ) (15 mg) was administered daily. The TFEQ restraint scale was negatively related to 6 months weight loss. In particular, strategic dieting behaviour and a more controlled attitude towards self-regulation were negatively related to weight loss. A positive non-placebo controlled change in mood was found already after 2 months treatment. The changes in mood were not related to the weight loss. Patients with more unrestrained eating seem to have reduced their amount of food intake more radically with enhanced satiety, manifested by greater weight loss. Physiologically enhanced satiety could have the greatest weight loss effect for patients whose eating is more governed by hunger drives and appetite rather that by conscious efforts and cognitive control.
Effect of the learning curve on the early outcomes of laparoscopic Roux-en-Y gastric bypass.
Open gastric bypass has been demonstrated to provide durable weight loss in morbidly obese patients. As laparoscopic techniques have evolved surgeons are offering patients such an approach for performance of gastric bypass. The purpose of this study was to evaluate the relationship between increasing experience and outcome for this technically challenging operation. A retrospective analysis was performed on the initial 160 consecutive patients undergoing laparoscopic gastric bypass by a single surgeon over a 24-month period. Patients were divided into quartiles for data analysis. Duration of surgery decreased significantly between quartiles: 324 +/- 124, 225 +/- 70, 190 +/- 47, and 168 +/- 40 minutes, respectively (P < 0.01). However, the conversion rate (3.1%) and mean hospital length of stay (2.1 +/- 2.4 days) were unaffected by surgeon experience. The early and late postoperative complication rates were 9.4 and 3.1 per cent, respectively. Early complications included: leak (1.3%), bleeding (3.8%), obstruction (1.9%), acute gastric distention (0.6%), subphrenic abscess (0.6%), and wound infection (0.6%). Late complications include: obstruction (1.3%), anastomotic stricture (1.3%), and marginal ulcer (0.6%). The complication rates did not change statistically between quartiles. The excess weight loss at one year was 77.4 +/- 16.7 per cent. These data suggest that throughout the learning curve laparoscopic gastric bypass can be accomplished with acceptable complication rates, conversion rates, and hospital length of stay. Duration of surgery improves with experience. Early weight loss results compare favorably with those of open gastric bypass.
Neurobiologic changes in the hypothalamus associated with weight loss after gastric bypass.
BACKGROUND: Effects of Roux-en-Y gastric bypass (RYGB) on hypothalamic food intake regulation have not been investigated. The hypothalamic arcuate nucleus (ARC) and the magnocellular (m) and parvocellular (p) parts of the paraventricular nucleus (PVN) regulate hunger and satiety, and are under control of the orexigenic neuropeptide Y (NPY), and the anorexigenic alpha-melanocyte stimulating hormone (alpha-MSH) and serotonin (5-HT). We hypothesized that after RYGB, weight loss is associated with hypothalamic down regulation of NPY and up regulation of 5-HT and alpha-MSH. STUDY DESIGN: obesity was induced in 12 Sprague Dawley rats using a high-energy diet for 7 weeks, and then the rats were divided into three groups (n = 4/group): RYGB, sham-operated pair-fed (PF), and sham-operated ad libitum (obese control). Ten days after operation, immunohistochemical quantification of NPY, alpha-MSH, and 5-HT(1B)-receptors in ARC and PVN was performed. Data were analyzed using ANOVA and Tukey's test. RESULTS: Body weight decreased in RYGB (417 +/- 21 g; mean +/- SE) and in PF (436 +/- 14 g) rats 10 days after operation compared with obese control rats (484 +/- 15 g; p < 0.05 for each comparison). NPY in ARC, pPVN, and mPVN decreased by 43%, 43%, and 61%, respectively in RYGB and by 55%, 42%, and 71% in PF, respectively, compared with obese controls (p < 0.05 for each pairwise comparison). RYGB versus PF did not show differences. alpha-MSH in ARC, pPVN and mPVN increased by 35%, 175%, and 67%, respectively in RYGB and by 29%, 162%, and 116% in PF, respectively, compared with obese controls (each p < 0.05). In mPVN, alpha-MSH significantly decreased by 23% in RYGB versus PF (p < 0.05). 5-HT-(1B)-receptor in pPVN increased by 58% in RYGB and by 26% in PF, compared with obese controls (p < 0.05). Compared with obese controls, 5HT-(1B)-receptor in mPVN increased by 39% in RYGB (p < 0.05) and by 9% in PF (p > 0.05). An increase of 5-HT-(1B)-receptor in pPVN and mPVN occurred in RYGB versus PF (p < 0.05). CONCLUSIONS: Obese rats that undergo weight loss after RYGB demonstrate changes in hypothalamic down regulation of NPY and up regulation of alpha-MSH and serotonin.
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