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The enigma of increased non-cancer mortality after weight loss in healthy men who are overweight or obese.
OBJECTIVE: To study effects on non-cancer mortality of observational weight loss in middle-aged men stratified for body mass index (BMI), taking a wide range of possible confounders into account. DESIGN: Prospective, population based study. SETTING: Male population of Malmo, Sweden. PARTICIPANTS: In all 5722 men were screened twice with a mean time interval of 6 years in Malmo, southern Sweden. They were classified according to BMI category at baseline (<21, 22-25, overweight: 26-30, and obesity: 30+ kg m(-2)) and weight change category until second screening (weight stable men defined as having a baseline BMI +/- 0.1 kg m(-2) year-1 at follow-up re-screening). MAIN OUTCOME MEASURES: Non-cancer mortality calculated from national registers during 16 years of follow-up after the second screening. Data from the first year of follow-up were excluded to avoid bias by mortality caused by subclinical disease at re-screening. RESULTS: The relative risk (RR; 95% CI) for non-cancer mortality during follow-up was higher in men with decreasing BMI in all subgroups: RR 2.64 (1.46-4.71, baseline BMI <21 kg m(-2)), 1.39 (0.98-1.95, baseline BMI 22-25 kg m(-2)), and 1.71 (1.18-2.47, baseline BMI 26+ kg m(-2)), using BMI-stable men as reference group. Correspondingly, the non-cancer mortality was also higher in men with increasing BMI, but only in the obese group (baseline BMI 26+ kg m(-2)) with RR 1.86 (1.31-2.65). In a subanalysis, nonsmoking obese (30+ kg m(-2)) men with decreased BMI had an increased non-cancer mortality compared with BMI-stable obese men (Fischer's test: P=0.001). The mortality risk for nonsmoking overweight men who increased their BMI compared with BMI-stable men was also significant (P=0.006), but not in corresponding obese men (P=0.094). CONCLUSIONS. weight loss in self-reported healthy but overweight middle-aged men, without serious disease, is associated with an increased non-cancer mortality, which seems even more pronounced in obese, nonsmoking men, as compared with corresponding but weight-stable men. The explanation for these observational findings is still enigmatic but could hypothetically be because of premature ageing effects causing so-called weight loss of involution.
The effect of weight change on nursing care facility admission in the NHANES I Epidemiologic Followup Survey.
Data from the first National Health and Nutrition Examination Survey Epidemiologic Followup Survey were used to examine whether weight change was associated with an increased relative risk of nursing care facility admission. Hazard ratios were calculated with Cox proportional hazards models and stratified by overweight status at baseline. Moderate and large weight loss was associated with an increased risk of nursing care facility admission in overweight and non-overweight subjects. Large weight gain was associated with an increased relative risk in only overweight subjects. In the process of functional decline that results in nursing care facility admission, weight loss may be a sign of acute illness, starvation, or aging. Preventing weight loss may help delay this process of decline. In overweight subjects, preventing weight gain may also be important in delaying this process of decline.
Who will lose weight? A reexamination of predictors of weight loss in women.
BACKGROUND: The purpose of this study was to analyze pretreatment predictors of short-term weight loss in Portuguese overweight and obese women involved in a weight management program. Behavioral and psychosocial predictors were selected a priori from previous results reported in American women who participated in a similar program. METHODS: Subjects were 140 healthy overweight/obese women (age, 38.3 +/- 5.9 y; BMI, 30.3 +/- 3.7 kg/m2) who participated in a 4-month lifestyle weight loss program consisting of group-based behavior therapy to improve diet and increase physical activity. At baseline, all women completed a comprehensive behavioral and psychosocial battery, in standardized conditions. RESULTS: Of all starting participants, 3.5% (5 subjects) did not finish the program. By treatment's end, more than half of all women had met the recomended weight loss goals, despite a large variability in individual results (range for weight loss = 19 kg). In bivariate and multivariate correlation/regression analysis fewer previous diets and weight outcome evaluations, and to a lesser extent self-motivation and body image were significant and independent predictors of weight reduction, before and after adjustment for baseline weight. A negative and slightly curvilinear relationship best described the association between outcome evaluations and weight change, revealing that persons with very accepting evaluations (that would accept or be happy with minimal weight change) lost the least amount of weight while positive but moderate evaluations of outcomes (i.e., neither low nor extremely demanding) were more predictive of success. Among those subjects who reported having initiated more than 3-4 diets in the year before the study, very few were found to be in the most successful group after treatment. Quality of life, self-esteem, and exercise variables did not predict outcomes. CONCLUSIONS: Several variables were confirmed as predictors of success in short-term weight loss and can be used in future hypothesis-testing studies and as a part of more evolved prediction models. Previous dieting, and pretreatment self-motivation and body image are associated with subsequent weight loss, in agreement with earlier findings in previous samples. Weight outcome evaluations appear to display a more complex relationship with treatment results and culture-specific factors may be useful in explaining this pattern of association.
Cytokine pattern is solely influenced by priming vaccine but immunity and disease by both priming and boosting vaccines in mice challenged with respiratory syncytial virus.
Vaccine formulation can influence cytokine and disease patterns in mice following respiratory syncytial virus (RSV) challenge. The influence of different live and killed dual-vaccine combinations on subsequent immune responses was investigated. BALB/c mice received either killed followed by killed (KV/KV), killed followed by live (KV/LV), live followed by killed (LV/KV), or live followed by live (LV/LV) RSV vaccines intramuscularly. Mouse weight loss, viral replication, cytokine expression patterns, immunoglobulin isotype antibody profiles, neutralizing antibody responses, and cytotoxicity T lymphocyte (CTL) activities in lungs were compared on subsequent live RSV challenge. On challenge, mice vaccinated initially with KV and boosted with either KV or LV expressed significantly skewed ratios of IL-4 to IFN-gamma mRNA and IgG1 to IgG2a antibody, when compared to those vaccinated initially with LV. Low levels of RSV replication were detected in lungs of mice vaccinated with KV/KV, KV/LV, and LV/KV, but not in mice vaccinated with LV/LV. Mice vaccinated with KV/LV, LV/KV, or LV/LV had RSV-specific CTL activity in lungs six days after RSV challenge, while no CTL activity was detected in KV/KV-vaccinated mice. Mice vaccinated with KV/KV had the greatest weight loss, while LV/LV-vaccinated mice resulted in the least. Mice vaccinated with either KV/LV or LV/KV had intermediate weight loss after challenge. These data indicate that an original antigenic sin-like phenomenon was exhibited in cytokine and immunoglobulin isotype responses in mice after challenge. T helper (Th)-like immune responses were determined solely by the initial vaccination, while weight loss, viral replication, neutralizing antibody responses, and CTL activities were also influenced by boosted vaccinations.
Malabsorptive gastric bypass in patients with superobesity.
weight loss in superobese patients has been problematic after conventional gastric restrictive operations including conventional Roux-en-Y gastric bypass (RYGB). The goal of the present study was to compare weight loss in patients with superobesity (body mass index > or =50 kg/m(2)) using a distal RYGB (D-RY) in which the Roux-en-Y anastomosis was performed 75 cm proximal to the ileocecal junction (N = 47) vs. patients who had Roux limbs of 150 cm (N = 152) and 50 to 75 cm (N = 99). All operations incorporated the same gastric restrictive parameters. Minimum follow-up was 3 years and ranged to 16 years. weight loss and reduction in body mass index were significantly greater after D-RY vs. both RYGB-150 cm and short RYGB and in RYGB-150 cm vs. short RYGB through 5 years. Mean percentage of excess weight loss peaked at 64% after DRY, at 61% after RYGB-150 cm, and at 56% after short RYGB. weight loss maintenance through 5 years was correlated with Roux limb length with D-RY greater than RYGB-150 cm greater than short RYGB. More than 95% of obesity-related comorbid conditions improved or resolved with weight loss. There was no difference in the early postoperative morbidity rates: 9% after D-RY; 8% after RYGB-150 cm; and 2% after short RYGB with one death (0.3%). All D-RY patients had at least one postoperative metabolic abnormality. Anemia was significantly more common after D-RY vs. the shorter RYGB with no difference in the incidence of metabolic sequelae between RYGB-150 cm and short RYGB. No operations were reversed or modified for nutritional complications. Two D-RY patients required total parenteral nutrition for protein malnutrition. These results show that Roux limb length is correlated with weight loss in superobese patients. However, the greater incidence of metabolic sequelae after D-RY vs. RYGB-150 cm calls into question its routine use in superobese patients undergoing bariatric surgery. We conclude that some degree of malabsorption should be incorporated into bariatric operations performed in superobese patients to achieve satisfactory long-term weight loss.
Who succeeds in maintaining weight loss? A conceptual review of factors associated with weight loss maintenance and weight regain.
weight loss is difficult to achieve and maintaining the weight loss is an even greater challenge. The identification of factors associated with weight loss maintenance can enhance our understanding for the behaviours and prerequisites that are crucial in sustaining a lowered body weight. In this paper we have reviewed the literature on factors associated with weight loss maintenance and weight regain. We have used a definition of weight maintenance implying intentional weight loss that has subsequently been maintained for at least 6 months. According to our review, successful weight maintenance is associated with more initial weight loss, reaching a self-determined goal weight, having a physically active lifestyle, a regular meal rhythm including breakfast and healthier eating, control of over-eating and self-monitoring of behaviours. Weight maintenance is further associated with an internal motivation to lose weight, social support, better coping strategies and ability to handle life stress, self-efficacy, autonomy, assuming responsibility in life, and overall more psychological strength and stability. Factors that may pose a risk for weight regain include a history of weight cycling, disinhibited eating, binge eating, more hunger, eating in response to negative emotions and stress, and more passive reactions to problems.
Vertical banded gastroplasty in the Aegean Region of Turkey.
BACKGROUND: obesity is increasing in Turkey. The first experience with vertical banded gastroplasty (VBG) with regular intermediate-term follow-up in the Aegean Region of Turkey is presented. METHODS: From November 1993 to August 1999, 40 morbidity obese patients underwent VBG. The patients were evaluated on the basis of excess weight loss (EWL) and satisfaction with the operation. RESULTS: Regular follow-up was obtained in 38 patients (95%), with mean follow-up 27.2 months (14-85). Average preoperative body weight (BW) was 141.4 kg (93-238) and body mass index (BMI) was 52.3 kg/m2 (41-77.8). Average EWL was 64.1% (21.2-92.3). Average postoperative BW and BMI were 93.3 kg (70-145) and 34.4 kg/m2 (25.1-53) respectively. 35 of 38 patients (92%) lost more than 25% of EW and 28 of 38 (73.6%) lost more than 50% of EW. After weight loss, hypertension disappeared or improved in 86% of patients and diabetes resolved in 75%. Sleep apnea disappeared in 100% of patients. The early and late complication rates were 7.9% and 15.8% respectively. 33 of 38 patients (87%) were satisfied with the operation. CONCLUSION: VBG was safe and effective, resulted in acceptable weight loss, and the vast majority of patients were satisfied.
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.
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