Overweight, obesity, and blood pressure: the effects of modest weight reduction

Several large epidemiological studies have shown an association between body mass index and blood pressure in normal weight and overweight patients. Weight gain in adult life especially seems to be an important risk factor for the development of hypertension. Weight loss has been recommended for the obese hypertensive patient and has been shown to be the most effective nonpharmacological treatment approach. However, long-term results of weight loss programs are disappointing with people often regaining most of the weight initially lost. In recent years, a modest weight loss, defined as a weight loss of 5% to 10% of baseline weight, has received increasing attention as a new treatment strategy for overweight and obese patients. A more gradual and moderate weight loss is more likely to be maintained over a longer period of time. Several studies have confirmed the blood pressure-lowering effect of a modest weight loss in both hypertensive and nonhypertensive patients. A modest weight loss can normalize blood pressure levels even without reaching ideal weight. In patients taking antihypertensive medication, a modest weight loss has been shown to lower or even discontinue the need for antihypertensive medication. In patients with high normal blood pressure, a modest weight loss can prevent the onset of frank hypertension. The blood pressure-lowering effect of weight loss is most likely a result of an improvement in insulin sensitivity and a decrease in sympathetic nervous system activity and occurs independent of salt restriction. In conclusion, a modest weight loss that can be maintained over a longer period of time is a valuable treatment goal in hypertensive patients.     

Effect of a hypocaloric diet on serum visfatin in obese non-diabetic patients

OBJECTIVE: Obesity and insulin resistance are associated with classic and new cardiovascular risk factors, such as inflammatory markers and adipocytokines. The aim of this study was to examine whether weight reduction could change visfatin serum concentrations in obese patients. METHODS: This was an interventional longitudinal study analyzing a population of 80 obese non-diabetic outpatients. Weight, blood pressure, fasting serum glucose, C-reactive protein, plasma insulin, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triacylglycerols, and insulin resistance (homeostatic model assessment) were measured before and after 3 mo on a hypocaloric diet. RESULTS: Eighty patients were enrolled. The mean age was 46.7 +/- 16.7 y, the mean body mass index was 34.1 +/- 4.8 kg/m(2), with 20 men (25%) and 60 women (75%). After 3 mo on a hypocaloric diet, body mass index, fat mass, waist circumference, systolic blood pressure, fasting serum glucose, total cholesterol, and low-density lipoprotein cholesterol decreased. The serum concentration of visfatin decreased with weight loss (112.14 +/- 70.2 versus 99.4 +/- 58.1 ng/mL, P < 0.05). In the multivariate analysis of visfatin concentration before and after treatment, as a dependent variable, only age remained an independent predictor in the model (F = 12.5, P < 0.02), with an inverse correlation: visfatin decreased 4.1 g/mL (F = 12.5, P < 0.05) and 3.7 g/mL (95% confidence interval 1.2-6.1), respectively, for each year of age. CONCLUSION: Weight reduction after a 3-mo period of a hypocaloric diet is associated with a significant decrease in circulating serum concentrations of the novel adipokine visfatin in obese subjects. Visfatin is inversely correlated with age.     

Impact of different levels of weight loss on blood pressure in overweight and obese women.

This study sought to determine the impact of different levels of weight loss on blood pressure in overweight/obese women. One hundred fifty-nine overweight/obese women (age 48.7 +/- 9.7, weight 101.3 +/- 18.7 kg, BMI 37.3 +/- 6.6 kg/m(2)) completed a six-month clinical weight loss program that included weekly nutrition, behavior, and exercise instruction. Participants consumed a very-low-energy diet (VLED) for 12 weeks. VLED was followed by four weeks of gradual reintroduction to solid foods. At week 16, participants received a diet to maintain weight or slightly reduce weight (<0.5 lb/week) which they followed for the duration of the study. All lab and blood pressure assessments were performed at baseline and six months. Three groups were formed according to the proportion of weight loss after six months; Group 1 had < 10% (n = 19), Group 2 had 10%-20% (n = 64), and Group 3 had >20% (n = 76) weight loss. Differences in systolic blood pressure (mm Hg) were found in dose response fashion for weight loss at six months with 125 +/- 17 (<10%), 119 +/- 13 (10%-20%), and 117 +/- 15 (>20%; p = 0.005). Differences in diastolic blood pressure (mm Hg) were also found in dose response fashion with 81 +/- 9 (<10%), 77 +/- 9 (10%-20%), and 75 +/- 9 (20%; p = 0.003). These data indicate that increasing weight loss beyond 10% of initial body weight may provide added improvements in blood pressure compared to less than 10% weight loss in overweight or obese women.     

Effect of gastric banding on aminoterminal pro-brain natriuretic peptide in the morbidly obese

OBJECTIVE: Aminoterminal pro-brain natriuretic peptide (NT-proBNP), like brain natriuretic peptide, might have diagnostic utility in detecting left ventricular hypertrophy and/or left ventricular dysfunction. The aim of the study was to investigate the relationship between morbid obesity and NT-proBNP and the effect of weight reduction on this parameter. RESEARCH METHODS AND PROCEDURES: A total of 34 morbidly obese patients underwent laparoscopic adjustable gastric banding (LAGB). NT-proBNP levels were measured before and 12 months after the surgery. RESULTS: Metabolic features and systolic and diastolic blood pressure were significantly decreased (p < 0.00001 for both) after a cumulative weight loss of 19.55 kg 1 year after LAGB. NT-proBNP concentration was significantly higher in morbidly obese patients before LAGB than in normal-weight control subjects (341.15 +/- 127.78 fmol/mL vs. 161.68 +/- 75.78 fmol/mL; p < 0.00001). After bariatric surgery, NT-proBNP concentration decreased significantly from 341.15 +/- 127.78 fmol/mL to 204.87 +/- 59.84 fmol/mL (p < 0.00001) and remained statistically significantly elevated (204.88 +/- 59.84 fmol/mL vs. 161.68 +/- 75.78 fmol/mL; p = 0.04) compared with normal-weight subjects. DISCUSSION: This investigation demonstrates higher levels of NT-proBNP in morbidly obese subjects and a significant decrease during weight loss after laparoscopic adjustable gastric banding. In obesity, NT-proBNP might be useful as a routine screening method for identifying left ventricular hypertrophy and/or left ventricular dysfunction.     

The relationship of health outcomes to improvement in BMI in children and adolescents

OBJECTIVE: To evaluate the clinical outcomes of patients participating in an outpatient program for managing childhood and adolescent obesity. RESEARCH METHODS AND PROCEDURES: Based on a retrospective chart review, 394 physician-referred obese youth (BMI > 95th percentile), 5 to 19 years of age, were treated in an interdisciplinary, family-centered, behavioral weight management program in a hospital-based outpatient setting. Treatment included group exercise, parent education, and behavioral intervention therapies to improve diet and physical activity. RESULTS: A total of 177 (45%) completed the initial phase of treatment (mean duration = 5.6 months). For the completion group, there were significant improvements (all p < 0.001) in weight (-2.0 +/- 4.9 kg), BMI (-1.7 +/- 1.9 kg/m(2)), and BMI z score (-0.15 +/- 0.15), without interfering with growth (height, 2.2 +/- 1.3 cm; p < 0.001). Significant improvement was also found for blood pressure, total cholesterol, low-density lipoprotein (LDL)-cholesterol, triglycerides, insulin, and aerobic fitness. At onset of treatment, 134 (84%) patients had abnormal fasting insulin concentration, 88 (50%) had abnormal total cholesterol, 14 (8%) had abnormal diastolic blood pressure, and 69 (40%) had abnormal LDL-cholesterol. At the end of treatment, a significant proportion of patients with baseline abnormal blood pressure, total cholesterol, and LDL-cholesterol had normal values (p < 0.001). A decrease in BMI z score was associated with significant improvements in insulin and lipid values (all p < 0.05). DISCUSSION: We have demonstrated that a modest decrease in BMI in an ongoing clinical pediatric weight management program is accompanied by significant improvements in related health measures. These results may be helpful in counseling families with overweight children and adolescents.     

Effects of sibutramine plus orlistat in obese women following 1 year of treatment by sibutramine alone: a placebo-controlled trial

OBJECTIVE: This study assessed whether adding orlistat to sibutramine would induce further weight loss in patients who previously had lost weight while taking sibutramine alone. RESEARCH METHODS AND PROCEDURES: Patients were 34 women with a mean age of 44.1 +/- 10.4 years, weight of 89.4 +/- 13.8 kg, and body mass index (BMI) of 33.9 +/- 4.9 kg/m2 who had lost an average of 11.6 +/- 9.2% of initial weight during the prior 1 year of treatment by sibutramine combined with lifestyle modification. Patients were randomly assigned, in double-blind fashion, to sibutramine plus orlistat or sibutramine plus placebo. In addition to medication, participants were provided five brief lifestyle modification visits during the 16-week continuation trial. RESULTS: Mean body weight did not change significantly in either treatment condition during the 16 weeks. The addition of orlistat to sibutramine did not induce further weight loss as compared with treatment by sibutramine alone (mean changes = +0.1 +/- 4.1 kg vs. +0.5 +/- 2.1 kg, respectively). DISCUSSION: These results must be interpreted with caution because of the study's small sample size. The findings, however, suggest that the combination of sibutramine and orlistat is unlikely to have additive effects that will yield mean losses > or =15% of initial weight, as desired by many obese individuals.     

Experimental analysis of adherence counseling: implications for hypertension management

A time series "reversal" design demonstrated that behavioral counseling increased medication adherence from about 60 to 100% for a black, hypertensive patient. However, inadequate pharmacological treatment yielded no clinically important blood pressure decrease. The combination of improved compliance and minimal blood pressure reduction led the patient's physician to explore higher doses and alternate medications to achieve blood pressure control. The physician's aggressive medical treatment was initiated only after the patient's compliance had been improved. Thus, this study suggests that paraprofessional counseling can increase compliance and illustrates the need for both behavioral and physiological data in clinical management to avoid blaming patients for poorly controlled blood pressure.     

Dietary weight loss decreases serum angiotensin-converting enzyme activity in obese adults

OBJECTIVE: To study the effect of dietary weight loss, postural change, and an oral glucose load on serum angiotensin-converting enzyme (ACE) activity in obese adults. RESEARCH METHODS AND PROCEDURES: Sixteen obese adult men and women with a mean body mass index of 35.7 +/- 4.3 kg/m(2) were studied after 1 week on a maintenance energy lead-in diet and after 5 weeks on an identical but 40% reduced-energy diet provided by the General Clinical Research Center (GCRC). ACE activity was measured spectrophotometrically. Plasma renin activity and serum aldosterone were measured by radioimmunoassay. RESULTS: All subjects lost weight, with a mean decrease in body weight of 7.0 +/- 2.1 kg or 6 +/- 3% of initial body weight (p < 0.00001). Systolic and diastolic blood pressure, supine plasma renin activity, and serum aldosterone levels decreased with weight loss (p < 0.05). Supine ACE activity decreased 23 +/- 12% with weight loss (p < 0.00001). Standing ACE activity, which was significantly higher than supine ACE activity before and after weight loss (p < 0.05), also decreased 18 +/- 17% with weight loss (p = 0.0007). A 75-g oral glucose load had no effect on serum ACE activity over a 3-hour period. DISCUSSION: In obese adults, serum ACE activity declines with modest weight loss, increases with postural change, and is unaffected by an oral glucose load.     

Short-term effects of weight loss on the cardiovascular risk factors in morbidly obese patients

OBJECTIVE: To analyze the short-term effects of weight loss on the cardiovascular risk factors in morbidly obese patients. RESEARCH METHODS AND PROCEDURES: Five metabolic cardiovascular risk factors (blood glucose, blood pressure, total cholesterol, high-density lipoprotein (HDL)-cholesterol, and triglycerides) were determined before and 15.3 +/- 2.1 months after laparoscopic gastric banding in 650 morbidly obese patients. Global cardiovascular risk was calculated according to the Prospective Cardiovascular Münster (PROCAM) scoring system. RESULTS: Mean weight loss was 22.7 +/- 20.4 kg. Normalization of the metabolic alteration was observed in 67.3% of patients with diabetes, 38.3% of patients with hypercholesterolemia, 72.5% of patients with low HDL-cholesterol, 72.3% of patients with hypertriglyceridemia, and 46.7% of patients with hypertension. PROCAM score fell from 31.4 +/- 11.6 to 28.0 +/- 12.0 points (p < 0.001). The modifications of total cholesterol and blood pressure were unrelated to percentage weight loss. Percentage weight loss was significantly related to the reductions of fasting blood glucose, triglyceride level, and the PROCAM score and to the increase of HDL-cholesterol concentrations observed after surgery. However, the strength of these four relationships was generally low. The variations of HDL-cholesterol concentrations and blood pressure levels were more influenced by actual energy balance than by the extent of weight loss. DISCUSSION: Weight loss observed in the first 12 to 18 months after gastric banding was associated with a significant improvement of single cardiovascular risk factors and global risk. On the other hand, the extent of weight loss was poorly related to the magnitude of improvement in cardiovascular risk.     

Comparison of cardiovascular risk factors in obese blacks and whites

Blacks are known to have higher blood pressure levels, a higher prevalence of hypertension, and higher body weights than whites. However, the interrelationships of these and other cardiac risk factors have not been analyzed in an obese population. We compared blood pressure (BP) and lipid levels in 174 obese blacks and 939 obese white patients who were entering a weight loss program; we also assessed the effects of weight loss on these factors. Prevalence of treated hypertension was similar in blacks and whites (28% vs. 25%, respectively). In patients not taking BP medication, black women weighed more (108 kg) than white women (102 kg) and black and white males' weights were similar (135 kg vs. 131 kg). Systolic and diastolic BP were similar in black and white women; black males had similar SBP but a significantly lower DBP than white males (83 mmHg vs. 89 mmHg, respectively). Lipid levels were similar in black and white women except black women had lower triglycerides (1.30 mmol/L) than white women (1.58 mmol/L, p < 0.05); and black males compared to white males had significantly lower total cholesterol (4.76 mmol/L vs. 5.56 mmol/L), LDL-cholesterol (3.15 mmol/L vs. 3.52 mmol/L) and triglycerides (1.31 mmol/L vs. 2.17 mmol/L, p < 0.05). Adult-onset obesity adversely affected a number of cardiovascular risk factors in whites, but not in blacks. Blacks lost significantly less weight (-13 kg) than whites (-19 kg). However, controlling for the difference in weight loss, blacks sustained comparable improvement in lipids and blood pressure, except for TC/HDL-C (whites improved significantly more, -0.36 kg/m2, than blacks, 0.03 kg/m2). Thus, the impact of obesity on cardiovascular risk factors seems ameliorated in blacks compared to whites.     

Impact of visceral fat on blood pressure and insulin sensitivity in hypertensive obese women

OBJECTIVE: The relationship among body fat distribution, blood pressure, serum leptin levels, and insulin resistance was investigated in hypertensive obese women with central distribution of fat. RESEARCH METHODS AND PROCEDURES: We studied 74 hypertensive women (age, 49.8 +/- 7.5 years; body mass index, 39.1 +/- 5.5 kg/m(2); waist-to-hip ratio, 0.96 +/- 0.08). All patients were submitted to 24-hour blood pressure ambulatory monitoring (24h-ABPM). Abdominal ultrasonography was used to estimate the amount of visceral fat (VF). Fasting blood samples were obtained for serum leptin and insulin determinations. Insulin resistance was estimated by homeostasis model assessment insulin resistance index (HOMA-r index). RESULTS: Sixty-four percent of the women were postmenopausal, and all patients showed central distribution of fat (waist-to-hip ratio > 0.85). The VF correlated with systolic 24h-ABPM values (r = 0.28, p = 0.01) and with HOMA-r index (r = 0.27; p = 0.01). VF measurement (7.5 +/- 2.3 vs. 5.9 +/- 2.2 cm, p < 0.001) and the systolic 24h-ABPM (133 +/- 14.5 vs. 126 +/- 9.8 mm Hg, p = 0.04), but not HOMA-r index, were significantly higher in the postmenopausal group (n = 48) than in the premenopausal group (n = 26). No correlations were observed between blood pressure levels and HOMA-r index, leptin, or insulin levels. In the multiple regression analysis, visceral fat, but not age, body fat mass, or HOMA-r index, correlated with the 24h-ABPM (p = 0.003). DISCUSSION: In centrally obese hypertensive women, the accumulation of VF, more often after menopause, is associated with higher levels of blood pressure and insulin resistance. The mechanism through which VF contributes to higher blood pressure levels seems to be independent of leptin or insulin levels.     

Quercetin reduces blood pressure in hypertensive subjects

Epidemiological studies report that quercetin, an antioxidant flavonol found in apples, berries, and onions, is associated with reduced risk of coronary heart disease and stroke. Quercetin supplementation also reduces blood pressure in hypertensive rodents. The efficacy of quercetin supplementation to lower blood pressure in hypertensive humans has never been evaluated. We tested the hypothesis that quercetin supplementation reduces blood pressure in hypertensive patients. We then determined whether the antihypertensive effect of quercetin is associated with reductions in systemic oxidant stress. Men and women with prehypertension (n = 19) and stage 1 hypertension (n = 22) were enrolled in a randomized, double-blind, placebo-controlled, crossover study to test the efficacy of 730 mg quercetin/d for 28 d vs. placebo. Blood pressure (mm Hg, systolic/diastolic) at enrollment was 137 +/- 2/86 +/- 1 in prehypertensives and 148 +/- 2/96 +/- 1 in stage 1 hypertensive subjects. Blood pressure was not altered in prehypertensive patients after quercetin supplementation. In contrast, reductions in (P < 0.01) systolic (-7 +/- 2 mm Hg), diastolic (-5 +/- 2 mm Hg), and mean arterial pressures (-5 +/- 2 mm Hg) were observed in stage 1 hypertensive patients after quercetin treatment. However, indices of oxidant stress measured in the plasma and urine were not affected by quercetin. These data are the first to our knowledge to show that quercetin supplementation reduces blood pressure in hypertensive subjects. Contrary to animal-based studies, there was no quercetin-evoked reduction in systemic markers of oxidative stress.     

Multidisciplinary treatment of obesity with a protein-sparing modified fast: results in 668 outpatients.

Six hundred sixty-eight obese outpatients, 71 per cent (+/- 34) in excess of ideal weight, were enrolled in a multidisciplinary weight control program. The major components of the program included nutrition, education, behavior modification, and exercise. Rapid weight loss was accomplished using a very low calorie (less than 800 kcal) ketogenic diet. Patients adhered to the protein sparing modified fast (PSMF) for 17 +/- 12 weeks and averaged 9 +/- 17 weeks in a refeeding/maintenance program. Mean weight loss was 47 +/- 29 lb (21 +/- 13 kg) at the point of minimum weight and 41 +/- 29 lb (19 +/- 13 kg) at the end of the maintenance period. Systolic and diastolic blood pressure and serum triglycerides fell significantly in men and women. Success in weight loss was greatest in the heaviest patients, those who adhered the longest to the PSMF, and those who stayed the longest in the maintenance program.     

Imipramine and diet counseling with psychological support in the treatment of obese binge eaters: a randomized, placebo-controlled double-blind study.

OBJECTIVE: This study with 31 obese binge eaters (body mass index [BMI] 39.5+/-8.6 kg/m(2) [SD]) was designed to assess whether diet counseling with psychological support and imipramine or placebo has an effect on the frequency of binge eating, body weight, and depression during an 8-week treatment phase. This was followed by an open medication-free phase of 6 months of continuous diet counseling with psychological support. METHODS: Randomized double-blind placebo-controlled study of 8 weeks followed by an open phase of 6 months. Patients were evaluated in medical visits by a semistructured videotaped interview, psychometric questionnaires, and hematochemical parameters. RESULTS: From Week 0 to 8, a significant reduction in binge frequency occurred in both treatment conditions (7.1+/-4.1 to 2.8+/-3.0 binges per week [imipramine] vs. 7.1+/-4.1 to 5.4+/-5.1 [placebo], p<.01). Patients on imipramine lost -2.2+/-1.8 kg compared to placebo-treated subjects (+0.2+/-3.3 kg, p<.001). On follow-up, only the patients initially treated with imipramine continued to lose weight (-5.1+/-2.8 kg [imipramine] vs. 2.2+/-6.8 kg [placebo], p<.001 [differences to Week 0]). While both treatment conditions were associated with significant improvements on a rater's measure of depressive symptoms (Hamilton Depression Scale) at Week 8, only the patients treated with imipramine still showed a significant improvement at Week 32. Scores on the Self Depression Rating Scale did not show a group difference but a significant reduction at Weeks 8 and 32, compared to baseline. DISCUSSION: These results suggest that adding low-dose imipramine to diet counseling with psychological support helps patients losing weight even for at least 6 months off medication. The effect might include a psychological priming of weight loss during the double-blind phase that continues at least for half a year after stopping the drug.     

Nine-year changes in cardiovascular disease risk factors with weight maintenance in the atherosclerosis risk in communities cohort

Few studies have focused on the impact of weight maintenance on cardiovascular disease risk factors or addressed whether changes differ by baseline weight status and medication usage. The authors examined these issues using 9 years of follow-up data on 3,235 men and women from the Atherosclerosis Risk in Communities (ARIC) Study who were aged 45-64 years at baseline (1987-1989). In participants not using medications, glucose (3.0 mg/dl, 95% confidence interval (CI): 2.4, 3.5) and triglycerides (10.1 mg/dl, 95% CI: 8.3, 11.9) increased, while total cholesterol (-9.6 mg/dl, 95% CI: -10.6, -8.6), low density lipoprotein cholesterol (-9.9 mg/dl, 95% CI: -10.9, -9.0), and high density lipoprotein cholesterol (-1.7 mg/dl, 95% CI: -2.1, -1.3) decreased. Systolic blood pressure (7.9 mmHg, 95% CI: 7.3, 8.4) increased, but diastolic blood pressure (-1.1 mmHg, 95% CI: -1.4, -0.7) declined. Normal weight (body mass index: 18.5-<25.0 kg/m(2)) participants had smaller increases in glucose compared with obese (body mass index: >/=30.0 kg/m(2)) participants. In contrast, the authors found less favorable changes in total, low density lipoprotein, and high density lipoprotein cholesterol, triglycerides, and diastolic blood pressure among normal weight compared with obese participants who maintained their weight. These patterns were similar across weight status groups regardless of medication usage.     

Blood pressure and pulse pressure during long-term weight loss in the obese: the Swedish Obese Subjects (SOS) Intervention Study

OBJECTIVE: Recently we reported a complete relapse in the blood pressure (BP) of obese subjects despite a maintained 16% weight loss over 8 years. This relapse is now analyzed as a function of several variables. Pulse pressure (PP) is an independent risk factor of cardiovascular mortality. We now examine the development of PP in the obese and whether it can be modified by weight-reducing gastric surgery. RESEARCH METHODS AND PROCEDURES: A total of 1157 patients treated with gastric surgery and 1031 obese controls (body mass index of 41.0 +/- 4.6 kg/m(2) [mean +/- SD], age 48 +/- 6 years) were followed for 5.5 +/- 2.1 (range 3 to 10) years. To separate the effect of weight change from effect of time on BP, the patients were divided in cohorts based on follow-up time. RESULTS: Gastric surgery resulted in a maximum weight loss after 1 year that was followed by a moderate relapse. After 5.5 years, weight loss in the intervention group was 18 +/- 11% of initial body weight. Very little weight change was seen in controls. Systolic BP decreased in the intervention group during the first 6 months but had relapsed to control values at last examination. The adjusted change in PP was +4.7 mm Hg in obese controls but +2.9 mm Hg in the intervention group (p < 0.001). Final BP values were more closely related to follow-up time and ongoing weight increase than to initial body weight or initial weight loss. DISCUSSION: Effects of time (aging) and weight change per year on BP can be separated. An early increase in PP could be observed in the obese. This increase could be modified by weight-reducing gastric surgery.     

Effects of DMPA on weight and blood pressure in long-term acceptors.

The study of effects on weight and blood pressure in long term DMPA acceptors is reported. The objectives were to study body weight and blood pressure changes in long term DMPA users compared with intrauterine device (IUD) acceptors. A total of 50 healthy women who had been using DMPA for 120 months were compared with 50 IUD acceptors who had been using an IUD for 120 months. Age, parity, income, body weight, and blood pressure at the initiation of contraception were matched. The mean +/- SD body weight at 120 months in the DMPA and IUD groups were 60.9 +/- 7.5 kg and 62.1 +/- 9.3 kg. No difference in mean body weight was demonstrated. The blood pressure change between DMPA and IUD acceptors also was not different. It is suggested that long term DMPA use does not have unfavorable effects on weight or blood pressure.     

A weight reduction program preserves fat-free mass but not metabolic rate in obese adolescents

OBJECTIVE: To determine the effects of a multidisciplinary weight reduction program on body composition and energy expenditure (EE) in severely obese adolescents. RESEARCH METHODS AND PROCEDURES: Twenty-six severely obese adolescents, 12 to 16 years old [mean BMI: 33.9 kg/m(2); 41.5% fat mass (FM)] followed a 9-month weight reduction program including moderate energy restriction and progressive endurance and resistance training. Body composition was assessed by DXA, basal metabolic rate by indirect calorimetry, and EE by whole-body indirect calorimetry with the same activity program over 36-hour periods before starting and 9 months after the weight reduction period. RESULTS: Adolescents gained (least-square mean +/- SE) 2.9 +/- 0.2 cm in height, lost 16.9 +/- 1.3 kg body weight (BW), 15.2 +/- 0.9 kg FM, and 1.8 +/- 0.5 kg fat-free mass (FFM) (p < 0.001). Basal metabolic rate, sleeping, sedentary, and daily EE were 8% to 14% lower 9 months after starting (p < 0.001) and still 6% to 12% lower after adjustment for FFM (p < 0.05). Energy cost of walking decreased by 22% (p < 0.001). The reduction in heart rate during sleep and sedentary activities (-10 to -13 beats/min), and walking (-20 to -25 beats/min) (p < 0.001) resulted from both the decrease in BW and physical training. DISCUSSION: A weight reduction program combining moderate energy restriction and physical training in severely obese adolescents resulted in great BW and FM losses and improvement of cardiovascular fitness but did not prevent the decline in EE even after adjustment for FFM.     

Weight loss reduces tissue factor in morbidly obese patients

OBJECTIVE: To investigate the tissue factor (TF) pathway in clinical obesity and associated metabolic syndrome. RESEARCH METHODS AND PROCEDURES: Thirty-seven morbidly obese patients (4 men; BMI, 48 +/- 7 kg/m(2); range, 42 to 53 kg/m(2)), undergoing elective gastroplasty for the induction of weight loss, were examined for hemostatic, metabolic, and inflammatory parameters at baseline and 14 +/- 5 months postoperatively. RESULTS: Weight loss significantly reduced circulating plasma TF (314 +/- 181 vs. 235 +/- 113 pg/mL, p = 0.04), coagulation factor VII (130 +/- 22% vs. 113 +/- 19%, p = 0.023), and prothrombin fragment F1.2 (2.4 +/- 3.4 vs. 1.14 +/- 1.1 nM, p = 0.04) and normalized glucose metabolism in 50% of obese patients preoperatively classified as diabetic or of impaired glucose tolerance. The postoperative decrease in plasma TF correlated with the decrease of F1.2 (r = 0.56; p = 0.005), a marker of in vivo thrombin formation. In subgroup analysis stratified by preoperative glucose tolerance, baseline circulating TF (402.6 +/- 141.6 vs. 176.2 +/- 58.2, p < 0.001) and TF decrease after gastroplasty (DeltaTF: 164.7 +/- 51.4 vs. -81 +/- 31 pg/mL, p = 0.02) were significantly higher in obese patients with impaired glucose tolerance than in patients with normal glucose tolerance. DISCUSSION: Procoagulant TF is significantly reduced with weight loss and may contribute to a reduction in cardiovascular risk associated with obesity.     

Differences in glycaemic status do not predict weight loss in response to hypocaloric diets in obese patients

OBJECTIVE: The aim of our study was to detect differences in weigth loss with a hypocaloric diet in obese patients depending on their glycaemic status. SUBJECTS AND METHODS: A population of 76 obesity outpatients was analysed in a prospective way. The following variables were specifically recorded at basal time and after 3 months of hypocaloric diet (1200 kcal/day): weight, blood pressure, body mass index (BMI), waist circumference, and waist-hip ratio. Basal glucose, insulin, fibrinogen, cortisol, c-reactive protein, total cholesterol, LDL cholesterol, HDL cholesterol and triglycerides blood levels were measured. HOMA was calculated. An indirect calorimetry, tetrapolar electrical bioimpedance and a serial assessment of nutritional intake with 3 days written food records were performed. RESULTS: The mean age was 46.9 +/- 17.1 years and the mean BMI 34.6 +/- 5.3. All subjects were weight stable during the 2 weeks period preceding the study (body weight change, 0.3 +/- 0.1 kg). Anthropometric measurements showed an average waist circumference (108.7 +/- 15.7 cm), waist-to-hip ratio (0.93 +/- 0.11), and average weight (88.7 +/- 16.9 kg). Bipolar body electrical bioimpedance showed a fat mass of 37 +/- 12.3 kg. Indirect calorimetry showed a resting metabolic rate (RMR) (1674.3 +/- 392 kcal/day). Patients were divided in to two groups by glycaemic status (group I: normal glycaemic metabolism, fasting glucose levels <109 mg/dl; n = 50) and (group II: impaired glycaemic metabolism, fasting glucose levels >110 mg/dl, n = 26). Waist circumference (I: 108 +/- 17.1cm vs. 104.6 +/- 16.7 cm; P < 0.05) and (II: 113.6 +/- 9.8 cm vs. 110.9 +/- 8.9 cm; P < 0.05), weight (I: 90.6 +/- 19.2 kg vs. 86.3 +/- 18.6 kg:P < 0.05) and (II: 89.2 +/- 11.3 kg vs. 86.4 +/- 11.6 kg: P < 0.05) and BMI (I: 34.2 +/- 5.6 vs. 33.7 +/- 5.5; P < 0.05) and (II: 34.8 +/- 4.2 vs. 34.2 +/- 4.6; P < 0.05) improved in both groups with hypocaloric diet. Blood systolic pressure, total cholesterol and LDL cholesterol improved in both groups, without statistical differences. In group II improved glucose levels and HOMA index, too. Patients of group II had higher systolic blood pressure, glucose, total cholesterol, LDL cholesterol, triglycerides, lipoprotein (a), RCP levels and HOMA index than patients in group I. ANOVA analysis did not show differences among weight loss in tertiles of HOMA and glucose. CONCLUSION: Ability to lose weight on a hypocaloric diet over a 3-month time period does not vary in obese patients as a function of glycaemic status. Improvement in cardiovascular risk factors is not related with glycaemic status, too.