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Activity-induced GLP-1 release in lean and obese subjects.
The aim of the study was to determine whether physical activity stimulates GLP-1 release on the short-term in normal weight and in obese subjects compared to rest and, furthermore, whether modest weight loss affects GLP-1 release or sensitivity in the obese. Normal weight (n=28; 12 males, 16 females; BMI 22.9+/-1.4; age 35+/-12.7), as well as obese subjects (n=27; 21 males, 6 females; BMI 30.9+/-2.7; age 47.1+/-11.86) were tested in a resting and a physical activity condition. Obese subjects were matched over two groups for a weight loss period of 3 months. After weight loss, the tests were repeated. The area under the curve (AUC pmol/lxmin) for GLP-1 concentrations was significantly increased in the physical activity condition compared to rest in lean subjects (P=0.05) as well as in the obese subjects after weight loss (P<0.05), but not in the obese subjects before weight loss. Physical activity-stimulated GLP-1 release in lean and obese subjects after a weight loss period supports the idea of a neuroendocrine loop in addition to distal-intestinal stimulation of GLP-1 release. Modest weight loss might be effective for increasing GLP-1 sensitivity to acute stimulation.
Effects of identical weight loss on body composition and features of insulin resistance in obese women with high and low liver fat content.
Our objective was to determine how 8% weight loss influences subcutaneous, intra-abdominal, and liver fat (LFAT), as well as features of insulin resistance, in obese women with high versus low LFAT. A total of 23 women with previous gestational diabetes were divided into groups of high (9.4 +/- 1.4%) and low (3.3 +/- 0.4%) LFAT based on their median LFAT (5%) measured with proton spectroscopy. Both groups were similar with respect to age, BMI, and intra-abdominal and subcutaneous fat. Before weight loss, women with high LFAT had higher fasting serum insulin and triglyceride concentrations than women with low LFAT. At baseline, LFAT correlated with the percent of fat (r = 0.44, P < 0.05) and saturated fat (r = 0.45, P < 0.05) of total caloric intake but not intra-abdominal or subcutaneous fat or fasting serum free fatty acids. weight loss was similar between the groups (high LFAT -7.4 +/- 0.2 vs. low LFAT -7.7 +/- 0.3 kg). LFAT decreased from 9.4 +/- 1.4 to 4.8 +/- 0.7% (P < 0.001) in women with high LFAT and from 3.3 +/- 0.4 to 2.0 +/- 0.2% (P < 0.001) in women with low LFAT. The absolute decrease in LFAT was significantly higher in women with high than low LFAT (-4.6 +/- 1.0 vs. -1.3 +/- 0.3%, P < 0.005). The decrease in LFAT was closely correlated with baseline LFAT (r = -0.85, P < 0.001) but not with changes in the volumes of intra-abdominal or subcutaneous fat depots, which decreased similarly in both groups. LFAT appears to be related to the amount of fat in the diet rather than the size of endogenous fat depots in obese women. Women with initially high LFAT lost more LFAT by similar weight loss than those with low LFAT, although both groups lost similar amounts of subcutaneous and intra-abdominal fat. These data suggest that LFAT is regulated by factors other than intra-abdominal and subcutaneous fat. Therefore, LFAT does not appear to simply reflect the size of endogenous fat stores.
Laparoscopic Swedish adjustable gastric banding: a five-year prospective study.
BACKGROUND: Laparoscopic adjustable gastric banding is a popular bariatric operation in Europe. However, the long-term complication rate and weight loss are still unclear. METHODS: 824 patients underwent a laparoscopic Swedish Adjustable Gastric Banding (SAGB) in a 5-year period. Preoperative data, postoperative weight loss and long-term complications were prospectively obtained for analysis. RESULTS: Mean age of the 824 patients was 43 +/- 1 years, with mean preoperative BMI 43 +/- 1 kg/m(2). No intra- or postoperative death occurred in the first 30 postoperative days. Intraoperative conversion rate was 5.2%. Peri-operative complication rate was 1.2%. 97% of the patients were available for follow-up (maximum 5 years). Long-term complications occurred in 191 patients (23.2%). 135 complications (16.4%) were related to the band, and 56 (6.8%) to the access-port or to the tube. Mean excess weight loss was 30, 41, 49, 55 and 57 % after 1, 2, 3, 4 and 5 years respectively. 82.9% of the patients obtained >50% EWL after initial treatment. CONCLUSIONS: The results of this study suggest that laparoscopic SAGB can achieve an effective weight loss, with an acceptable mortality and morbidity rate.
Bariatric weight loss surgery: patient education, preparation, and follow-up.
Bariatric weight loss surgery is no small undertaking. It requires a lifelong commitment on the part of the patient. Education is the key to helping patients achieve optimal health and a better quality of life as a result of having undergone weight loss surgery.
Tipping the scales: the effect of literacy on obese patients' knowledge and readiness to lose weight.
OBJECTIVES: The purpose of this study was to determine the association between the literacy level of overweight/obese patients and their weight-loss knowledge, attitudes, and readiness. METHODS: Structured patient interviews and a literacy screening instrument were administered in two primary care clinics at a university-based public hospital. RESULTS: A convenience sample of 210 overweight or obese adult outpatients (body mass index > or =25 kg/m2 or > or =30 kg/m2, respectively) were enrolled. Mean respondent age was 52 years; 74% were female, and 76% were black. Two thirds of patients read below a 9th grade level. Half of patients across all literacy levels reported currently attempting weight loss. There was a significant relation between literacy level and weight-loss knowledge, attitudes, and readiness (P < 0.05). CONCLUSIONS: Patients with low literacy were significantly less likely to understand the adverse health consequences of obesity and the need to lose weight and to report being ready to lose weight. Patient education and counseling for weight loss should be tailored for patients with low literacy skills.
Association of intentional changes in body weight with coronary heart disease event rates in overweight subjects who have an additional coronary risk factor.
Despite evidence that weight loss improves the severity of coronary heart disease (CHD) risk factors, a direct association between weight loss and CHD incidence has not been demonstrated. In 1994-2001, the authors conducted an observational study of intentional weight loss as related to CHD incidence among patients recruited from a network of clinics in Israel who received nutritional counseling from a dietitian to support the medical recommendation to lose weight. Subjects were outpatients aged 50-75 years with a body mass index of > or =27 kg/m(2), without CHD or cancer but with at least one risk factor for CHD in addition to overweight. Outcomes were documented over 4 years by repeated weight measurements and by medical record verification. Among 1,669 patients, 224 (13.4%) incidents of CHD were recorded. For subjects who underwent at least 6 months of dietetic counseling, the risk-factor-adjusted odds ratio for CHD incidence associated with a weight loss of 4.5 kg (the median level of weight loss) was 0.57 (95% confidence interval: 0.39, 0.84). In this, the largest known study of its type reported to date, intentional weight loss from a 6-month diet predicted lower incidence of CHD over 4 years.
Ephedrine is a sympathicomimetic agent that stimulates the central nervous and cardiovascular systems and causes bronchodilatation. It is one of the alkaloids in the herb Ephedra which is the basis of several over-the-counter herbal products, among which a number of popular weight-loss products. The Dutch Inspectorate for Health Care has received reports of adverse reactions presumably associated with Ephedra-containing weight-loss products. These adverse reactions comprised mainly palpitations, stress, headache and insomnia. The Ministry of Health in Canada has recently requested a market recall of some ephedrine-containing herbal products in response to a large number of adverse reactions reported in association with these products. The adverse reactions included stroke, heart attacks, cardiac arrhythmias, seizures and psychotic disorders. The voluntary recall concerns especially products that were marketed without approval and contain Ephedra in combination with caffeine or other stimulants. In the Netherlands, the status of Ephedra-containing products is currently reconsidered.
Body fat distribution in white and black women: different patterns of intraabdominal and subcutaneous abdominal adipose tissue utilization with weight loss.
BACKGROUND: Intraabdominal adipose tissue (IAAT) is the body fat depot most strongly related to disease risk. Weight reduction is advocated for overweight people to reduce total body fat and IAAT, although little is known about the effect of weight loss on abdominal fat distribution in different races. OBJECTIVE: We compared the effects of diet-induced weight loss on changes in abdominal fat distribution in white and black women. DESIGN: We studied 23 white and 23 black women, similar in age and body composition, in the overweight state [mean body mass index (BMI; in kg/m(2)): 28.8] and the normal-weight state (mean BMI: 24.0) and 38 never-overweight control women (mean BMI: 23.4). We measured total body fat by using a 4-compartment model, trunk fat by using dual-energy X-ray absorptiometry, and cross-sectional areas of IAAT (at the fourth and fifth lumbar vertebrae) and subcutaneous abdominal adipose tissue (SAAT) by using computed tomography. RESULTS: weight loss was similar in white and black women (13.1 and 12.6 kg, respectively), as were losses of total fat, trunk fat, and waist circumference. However, white women lost more IAAT (P < 0.001) and less SAAT (P < 0.03) than did black women. Fat patterns regressed toward those of their respective control groups. Changes in waist circumference correlated with changes in IAAT in white women (r = 0.54, P < 0.05) but not in black women (r = 0.19, NS). CONCLUSIONS: Despite comparable decreases in total and trunk fat, white women lost more IAAT and less SAAT than did black women. Waist circumference was not a suitable surrogate marker for tracking changes in the visceral fat compartment in black women.
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