Modeling the impact of adjustable gastric banding on survival in patients with morbid obesity.

OBJECTIVE: Morbid obesity is associated with premature death. Adjustable gastric banding may lead to substantial weight loss in patients with morbid obesity. Little is known about the impact of weight loss on survival after adjustable gastric banding. We therefore developed a mathematical model to estimate life expectancy in patients with a body mass index (BMI) > or =40 kg/m(2) undergoing bariatric surgery. RESEARCH METHODS AND PROCEDURES: We developed a nonhomogeneous Markov chain consisting of five states: the absorbing state ("dead") and the four recurrent states BMI > or =40 kg/m(2), BMI 36 to 39 kg/m(2), BMI 32 to 35 kg/m(2), and BMI 25 to 31 kg/m(2). Scenarios of weight loss and age- and sex-dependent risk of death, as well as BMI-dependent excess mortality were extracted from life tables and published literature. All patients entered the model through the state of BMI > or =40 kg/m(2). RESULTS: In men aged either 18 or 65 years at the time of surgery, who moved from the state BMI > or =40 kg/m(2) to the next lower state of BMI 36 to 39 kg/m(2), life expectancy increased by 3 and 0.7 years, respectively. In women aged either 18 or 65 years at the time of surgery, who moved from the state BMI > or =40 kg/m(2) to the next lower state BMI 36 to 39 kg/m(2), life expectancy increased by 4.5 and 2.6 years, respectively. weight loss to lower BMI strata resulted in further gains of life expectancy in both men and women. DISCUSSION: Within the limitations of the modeling study, adjustable gastric banding in patients with morbid obesity may substantially increase life expectancy.

Thermogenesis and weight loss in obese individuals: a primary association with organochlorine pollution.

The main objective of this study was to investigate the potential impact of body organochlorine (OC) pollution on the adaptive change in thermogenesis induced by body weight loss. Fat mass (FM), fat-free mass (FFM), and sleeping metabolic rate (SMR) were measured in obese individuals before and after a weight-reducing program. The measured values of SMR were then compared to those predicted from a reference equation established from FM and FFM in control subjects. Plasma OC, leptin, total tri-iodothyronine, and free thyroxine concentrations were also measured in obese subjects before and after weight loss. After weight loss, the measured decrease in SMR was greater than that predicted by changes in FM and FFM. Increased plasma OC concentration was the factor explaining the greatest proportion of the difference between predicted and measured SMR changes induced by body weight loss. OC pollution seems to be a new factor affecting the control of thermogenesis in some obese individuals experiencing body weight loss.

Neck circumference a good predictor of raised insulin and free androgen index in obese premenopausal women: changes with weight loss.

OBJECTIVE: Severe obesity can be associated with evidence of androgen excess and insulin resistance, which are features of the metabolic and polycystic ovary syndromes (PCOS). In this study, we examined the association between clinical and biochemical features of these syndromes and assess changes with weight loss. DESIGN: A consecutive series of 107 severely obese premenopausal women presenting for obesity surgery. MEASUREMENTS: Pre-operative assessment included details of clinical comorbidity, anthropometric measures and biochemical measures, including fasting insulin, glucose, lipid profile and sex hormone analysis. Changes in these measures for 42 of 52 (81%) patients at 1 year post surgery are reported. RESULTS: Neck circumference and younger age were independent predictors of higher free androgen index (FAI) (combined r2 = 0.36). If neck circumference is not included, then younger age, higher body mass index and raised fasting insulin levels were all independent predictors of FAI (r2 = 0.29). Waist to hip ratio showed no predictive value (r = 0.14). Neck circumference was also a good clinical predictor of menstrual irregularity, hirsutism, infertility, insulin resistance and the PCOS. Neck circumference of less than 39, 39-42 and greater than 42 cm reflect a low, intermediate and high risk of the metabolic and PCOS syndromes in obese premenopausal women. For 42 patients who were followed for 1 year after surgery, the weight loss was associated with reduction of FAI, less insulin resistance and improved menstrual regularity and resolution of the PCOS in 11 of 12 cases. CONCLUSIONS: Neck circumference is a good predictive measure of hyperinsulinaemia and raised androgens in obese premenopausal women. weight loss following surgery improves ovarian function and vasculopathic risk.

Long-term follow-up of untreated patients with sleep apnoea syndrome.

Obstructive sleep apnoea (OSA) is a common disorder with numerous potential sequelae. Although the majority of these consequences can be reduced with appropriate treatment, only limited data exist regarding the natural progression ofthis disorder in untreated individuals. We hereby report a long-term follow-up of all untreated patients (n = 40) followed-up in the Technion Sleep Clinic, using both subjective and objective measurements. In addition, we report a long-term follow-up of 11 patients who attempted dietary weight loss. The average time interval between the first and second polysomnographies for the untreated group was 5.0 +/- 2.8 yrs, and 2.5 +/- 2.3 yrs for the weight reduction group. There was no significant change in Body Mass Index (BMI) or Respiratory Disturbance Index (RDI) between the two Polysomnographic (PSG) evaluations in the untreated patients. However, eight patients developed hypertension (n=5) or ischaemic heart disease (IHD) (n=3) between the two evaluations. RDI, age and BMI at the time ofthe initial evaluation were not predictive of changes in RDI, snoring intensity or minimal oxygen saturation. However, the patients who developed hypertension/IHD had significantly higher RDI than the patients who did not (46 +/- 27 vs. 23 +/- 17 h(-1), P < 0.005). In the weight-loss group, BMI decreased by a mean of 3.1 kg m(-2), and RDI decreased by 20events h(-1), P<0.05 for both.There was a significant correlation between the weight loss and improvement in RDI (R = 0.75, P = 0.005). We conclude that in untreated obstructive sleep apnoea patients RDI does not necessarily increase over time, but associated hypertension or ischaemic heart disease may develop.When weight loss is successfully achieved, sleep apnoea significantly improves with a high correlation between the extent of weight loss and the improvement in apnoea status.

Examining effectiveness of Ahmadreza Movahedi's metabolic theory and model for weight control.

Is it possible to establish a dietary program for weight loss or gain in which hypothalamus may not be stimulated in decline or increase Basal Metabolic Rate? The purpose of this study was to examine Ahmadreza movahedi's metabolic theory and model for weight control.18 healthy male and female (25 to 50 years old) were assigned to three groups. Group A experienced weight loss metabolic program, they decreased 10% of their normal daily calorie for three days (action phase) and returned to their normal daily calorie for one day (changing return phase) (We called this 3 and 1 day cycle). They observed it for twelve days and for the second twelve day period they decreased 15% of their normal daily calorie for the action phases and returned to their normal daily calorie minus 5% for the changing return phases. The decreases for the remaining twelve -day periods were 20%, 25%, 30%, for the action phases and 5%, 10%, 10%, for the changing return Phases alternatively. The program went on so that at the last nine twelve -day period the calorie decreased for action phases was 30% and for the changing return phases was 10%. Group B followed weight gain metabolic program just like the program for weight loss group except that they increased the percents instead of decrease. Group C was as control group. The total period for the experimental and control groups was 60 days. To analyze data T test was used. Results: Group A decreased their body weight from 86.5 kg to 79.33 kg that was significant. Group B gained 2.16kg that was significant. No significant change in body weight was seen in control group. Theory: It is possible to establish a proper diet program for regulating relationship among hypothalamus, Basal metabolism, routine metabolism and calorie consumption to modify body weight (I.e weight loss and weight gain). Model : By modifying the amount of calories consumption in each meal for a given period of time (I.e for three days: The action phase) and observing the previous dietary habit for a short period of time (I.e for one day: Changing return phase) with progressive changes in the calorie of action phase and return phase and follow the cycle for a long period of time (I.e for one or two months), it is possible to regulate human metabolic rate properly so that one may lose his/her excess weight (or gain weight) without any side effect.The amount of calories that is to be modified and the periods in each cycle, may be varied according to one's individual differences.The next step is to establish a new dietary habit for the reference part of the cycle.

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.

Weight Loss and exercise: implications for muscle lipid metabolism and insulin action.

Implications for Muscle Lipid Metabolism and An accumulation of intramuscular lipid has been reported with obesity and linked with insulin resistance. The purpose of this paper is to discuss: 1) mechanisms that may be responsible for intramuscular lipid accumulation with obesity, and 2) the effects of common interventions (weight loss or exercise) for obesity on skeletal muscle lipid metabolism and intramuscular lipid content. Data suggest that the skeletal muscle of morbidly obese humans is characterized by the preferential partitioning of lipid toward storage rather than oxidation. This phenotype may, in part, contribute to increased lipid deposition in both muscle and adipose tissue, and promote the development of morbid obesity and insulin resistance. weight loss intervention decreases intramuscular lipid content, which may contribute to improved insulin action. On the other hand, exercise training improves insulin action and increases fatty acid oxidation in the skeletal muscle of obese/morbidly obese individuals. In summary, the accumulation of intramuscular lipid appears to be detrimental in terms of inducing insulin resistance; however, the accumulation of lipid can be reversed with weight loss. The mechanism(s) by which exercise enhances insulin action remains to be determined.

Pork quality, processing, and sensory characteristics of dry-cured hams as influenced by Duroc crossing and sex.

This study was designed to evaluate Duroc (DU) crossing for Carso dry-cured ham production. One hundred fifty-four pigs (81 females and 73 castrates) of four different genotypes, pure Landrace pigs (LAN), offspring of LAN females crossed with Large White (LW) males (LWxLAN), offspring of LAN females crossed with DU males (DUxLAN), and offspring of LWxLAN females crossed with DU males (DUx[LWxLAN]), were chosen in the weight range of 105 to 120 kg (112.7 +/- 0.4 kg). Raw material quality was evaluated for ham fatness (intra- and intermuscular and subcutaneous) and meat quality (pH, color, water-holding capacity) of longissimus dorsi, biceps femoris, and semimembranosus muscles. Ham weight losses were recorded at different stages of processing. The biceps femoris and semimembranosus muscles were analyzed for chemical composition before (lipid, moisture, total nitrogen, nonprotein nitrogen) and after (moisture, salt, total nitrogen, nonprotein nitrogen) processing. Chemical and sensory analyses were performed on 96 dry hams (12 castrates and 12 females per genotype). Biceps femoris and semimembranosus muscles were evaluated for color, saltiness, aroma, and texture. Pigs of the four genotypes had similar ham fatness as estimated by subcutaneous fat thickness. Duroc crosses exhibited higher intramuscular fat content, marbling, and intermuscular fat. Crossing with DU resulted in lower weight losses during ham processing. Castrates were fatter and had more intra- and intermuscular fat and lower ham processing weight losses than females. A strong negative relationship between ham fatness and ham processing losses was observed. Chemical and sensory traits of dry ham muscles were little affected by DU crossing. Lower salt content of biceps femoris was found in DU crosses. Dry hams from female pigs had higher total and nonprotein nitrogen, but drier, firmer texture and higher resistance to cutting force compared to dry hams from castrated pigs. Crossing with DU demonstrated some disadvantages (more intermuscular fat, more slice visible fat) and advantages (lower weight loss and salt intake) for the quality of dry-cured ham.