Biomedical subjects

M Apfelbaum

Publications and source records attributed to M Apfelbaum.

At least 19 recordsLinked to original sources

PubMed1999

Long-term maintenance of weight loss after a very-low-calorie diet: a randomized blinded trial of the efficacy and tolerability of sibutramine.

BACKGROUND: Very-low-calorie diets are a well established method to achieve substantial short-term weight loss in obese patients, but long-term maintenance of the weight loss is very disappointing. A combined very-low-calorie diet and pharmacologic approach could be an effective means of prolonging its benefits. PATIENTS AND METHODS: Eligible patients had a body-mass index greater than 30 kg/m2; those who lost 6 kg or more during a 4-week treatment with a very-low-calorie diet were randomly assigned to 1 year of treatment with sibutramine (10 mg) or identical placebo. RESULTS: In an intention-to-treat analysis, mean (+/-SD) absolute weight change at 1 year (or study endpoint) was -5.2 (+/-7.5) kg in the 81 patients in the sibutramine group and +0.5 (+/-5.7) kg in the 78 patients in the placebo group (P = 0.004). When compared with their weight at study entry (before the very-low-calorie diet), 86% of patients in the sibutramine group had lost at least 5% of their weight, compared with only 55% of those in the placebo group (P <0.001) at the study endpoint. Similarly, at month 12, 75% of subjects in the sibutramine group maintained at least 100% of the weight loss achieved with a very-low-calorie diet, compared with 42% in the placebo group (P <0.01). CONCLUSION: Following a very-low-calorie diet, sibutramine is effective in maintaining and improving weight loss for up to 1 year.

Adult↗

PubMed1998

Cost-effectiveness of coronary artery bypass surgery in octogenarians.

OBJECTIVE: The objective of this retrospective cohort study was to determine whether coronary artery bypass graft (CABG) surgery is effective and cost-effective relative to medical management of coronary artery disease (CAD) in the elderly. SUMMARY BACKGROUND DATA: The aging of the U.S population and the improvements in surgical techniques have resulted in increasing numbers of elderly patients who undergo this surgery. The three randomized, controlled trials (RCTs) that established the efficacy of CABG surgery completed patient enrollment from 19 to 24 years ago excluded patients older than 65 years. Although information regarding outcomes of CABG in this population is mainly available in case series, a major lacuna exists with respect to information on quality of life and cost effectiveness of surgery as compared with medical management. METHODS: The authors retrospectively formed surgical and medically managed cohorts of octogenarians with significant multivessel CAD. More than 600 medical records of patients older than 80 years who underwent angiography at our institution were reviewed to identify 48 patients who were considered reasonable surgical candidates but had not undergone surgery. This cohort was compared with 176 patients who underwent surgery. RESULTS: The cost per quality-adjusted life year saved was $10,424. At 3 years, survival in the surgical group was 80% as compared with 64% in the entire medical cohort and 50% in a smaller subset of the medical cohort. Quality of life in patients who underwent surgery was measurably better than that of the medical cohort with utility index scores, as measured by the EuroQoL, (a seven-item quality of life questionnaire) of 0.84, 0.61, and 0.74, respectively. CONCLUSIONS: Performing CABG surgery in octogenarians is highly cost-effective. The quality of life of the elderly who elect to undergo CABG surgery is greater than that of their cohorts and equal to that of an average 55-year-old person in the general population.

Age Factors↗

PubMed1997

Plasma levels of tissue plasminogen activator and plasminogen activator inhibitor-1 are correlated with the presence of transplant coronary artery disease in cardiac transplant recipients.

Hemostatic factors are involved in the pathogenesis of native coronary artery disease. However, their role in transplant coronary artery disease is less established. To assess the role of hemostatic factors in transplant coronary artery disease we studied 52 consecutive cardiac transplant patients. The presence of transplant coronary artery disease was determined by angiography. Plasma levels of tissue plasminogen activator (t-PA), plasminogen activator inhibitor-1 (PAI-1), von Willebrand Factor (vWF), and fibrin D-dimer were determined by enzyme-linked immunosorbent assays. Serum lipids were measured by enzymatic methods. Patients with transplant coronary artery disease had higher circulating t-PA (8.6 +/- 0.8 vs. 5.4 +/- 0.6 ng/ml, p = 0.021) and PAI-1 antigen concentrations (38.0 +/- 3.4 vs 25.8 +/- 2.2 ng/ml, p = 0.037). t-PA and PAI-1 antigen concentrations correlated with the severity of angiographic disease (R = 0.34; p = 0.014 for t-PA, and R = 0.45; p = 0.001 for PAI-1). Serum cholesterol levels were higher in patients with transplant coronary artery disease (221 +/- 7.6 vs 191 +/- 9.2 mg/dl, p = 0.039). Serum triglycerides were also higher in patients with transplant coronary artery disease by angiography (246 +/- 38.3 vs 139 +/- 20.8 mg/dl, p = 0.050). Multivariate analysis identified t-PA antigen (p = 0.003) and triglyceride levels (p = 0.038) as independent predictors for the presence of transplant coronary artery disease. We conclude that cardiac transplant patients with evidence of transplant coronary artery disease on coronary angiography have altered hemostatic function which is reflected by elevated levels of circulating t-PA and PAI-1 antigens. The interaction of the hemostatic system and serum lipids in the development of transplant coronary artery disease warrants further study.

Cholesterol↗

PubMed1997

Hind III polymorphism of the lipoprotein lipase gene and plasma lipid response to low calorie diet.

OBJECTIVE: To assess the effects of a low calorie diet on plasma lipids according to the Hind III polymorphism of the lipoprotein lipase (LPL) gene in overweight patients. DESIGN: Diet intervention study (25% restriction in energy intake during 2.5 months) in relation to genetic factors. SUBJECTS: 115 unrelated patients (77 women and 38 men) recruited on the basis of 120% of ideal body weight. MEASUREMENTS: Body weight, body mass index, blood lipids and lipoproteins, at entry and after 2.5 months, determination of LPL Hind III genotypes. RESULTS: On spontaneous diet, lipid and lipoproteins differed significantly between Hind III genotypes. Homozygous subjects for the presence of the Hind III cutting site, H2H2, had significantly higher plasma and VLDL triglyceride and apolipoprotein B concentrations than subjects carrying H1 allele. H2H2 subjects reduced their VLDL-triglyceride and apolipoprotein B concentrations more than H1 carriers, in such a way that differences in lipid levels according to genotypes were no more significant after diet. The magnitude of the decrease in triglycerides was positively correlated with the initial concentration but, among hypertriglyceridemic subjects, H2H2 still had the largest decrease in plasma and VLDL-triglycerides. CONCLUSION: The genetic variation at the LPL gene locus affects the response of serum lipid levels to caloric restriction. Overweight subjects with the H2H2 genotype of the LPL Hind III polymorphism are predisposed to hypertriglyceridemia but they are good responders to diet in terms of lipid levels.

Adult↗

PubMed1997

Increase in diet-induced thermogenesis at the start of refeeding in severely malnourished anorexia nervosa patients.

Many reports describe the difficulty for anorexia nervosa patients to gain weight during refeeding. To assess whether an increase in diet-induced thermogenesis (DIT) participates to this resistance, we studied DIT by indirect calorimetry in 11 severely malnourished anorexia nervosa patients [body mass index (BMI; in kg/m2) = 13] to accomplish two purposes: 1) to compare DIT in a strict semistarvation state with that obtained after 1 wk refeeding, when metabolism is shifted to a dynamic trend toward regaining weight, without significant change in body composition; 2) to study the effect on DIT of two energetic loads representing each one-third of the energy intake during semistarvation and refeeding, respectively: 1.25 and 2.92 MJ. To avoid bias, the two liquid loads were infused intragastrically in a random double-blind fashion. A significant increase in DIT during refeeding was observed for the two loads (204 +/- 23 kJ for the 1.25-MJ liquid meal and 482 +/- 78 kJ for the 2.92-MJ one, P < 0.02). The higher the load, the larger the increase with refeeding (P < 0.001). This increment in DIT exceeded the increase in active lean body mass and was poorly correlated with lean body mass. These results provide clear evidence of a strong cellular "waste" mechanism in anorexia nervosa patients during the early phase of refeeding, which enhances the adaptative resistance to overfeeding that we have already shown for resting energy expenditure.

Adolescent↗

PubMed1996

High resting energy expenditure in normal-weight bulimics and its normalization with control of eating behaviour.

Resting energy expenditure (REE) has been found to be lower in normal weight-bulimics (NWBs) than in controls and it was speculated that metabolic abnormalities might underlie bulimia. This study consisted of a longitudinal assessment of REE, body composition and energy intake before, during and after the control of eating behaviour, with comparisons between REEs in NWBs, those in controls, and estimated basal energy expenditure (EBEE). NWBs in acute phase of bulimia were assessed the 1st, 2nd, and last day of a one-week hospitalization that warranted compliance with normal diet. Assessments were then repeated after a six-week outpatient psychotherapy. Mean REE in NWBs was higher than that in controls and EBEE on admission. It decreased down to normal rate at discharge and at therapy termination. Fat-free mass (FFM) decreases slightly during hospitalization despite a weight-maintenance diet, but REE-FFM ratio also decreased significantly. Metabolic factors which might account for these results are discussed. Data suggest that: (1) caloric requirements in NWBs were higher than estimated weight-maintenance rations; (2) binge-eating increased REE; (3) control of eating behaviour decreased REE.

Adult↗

PubMed1996

Histologic appearance of transmyocardial laser channels after 4 1/2 weeks.

Preliminary results of clinical studies suggest that transmyocardial laser revascularization is an effective treatment for patients with chronic angina that cannot be treated by other means. The mechanism of this effect remains controversial. We present autopsy results from a patient obtained 4 1/2 weeks after operation that show that the channels do not maintain patency. Further work is needed to determine the frequency of channel patency and its relation to clinical benefit.

Aged↗

PubMed1996

Polymorphisms of uncoupling protein (UCP) and beta 3 adrenoreceptor genes in obese people submitted to a low calorie diet.

OBJECTIVE: To investigate whether the genetic polymorphisms of the uncoupling protein (UCP) and beta 3 adrenergic receptor (beta 3 AR) were associated with differences of weight loss in obese patients submitted to a low calorie diet. DESIGN: Longitudinal, clinical intervention study of a 25% restriction in energy intake with respect to genotypes. SUBJECTS: 163 patients with a body mass index above 27. MEASUREMENTS: Body weight and body mass index at baseline and after 2.5 months, genotypes by polymerase chain reaction followed by enzymatic digestion. RESULTS: For the UCP polymorphism, two alleles, 1 and 2 were identified with respective frequencies of 0.27 and 0.73. The allele 1 was associated with lower body weight loss after diet: 4,6,5.7 and 7.1 kg for the 1-1, 1-2 and 2-2 genotypes respectively (P < 0.05). No difference in weight loss was found according to the beta 3 AR Trp64Arg mutation. CONCLUSIONS: A genetic variant of the UCP gene is associated with a resistance to low calorie diet. This result, together with previous data on body weight gain, supports the hypothesis of a role of UCP and brown adipose tissue in the body weight regulation in humans. The importance of the Trp64Arg mutation of the beta 3 AR in the resistance to low calorie diet is still to demonstrate.

Adult↗

PubMed1995

Cognitive factors in the dietary response of restrained and unrestrained eaters to manipulation of the fat content of a dish.

This study examined the dietary intake and rated internal state of 16 normal-weight young women following the manipulation of the actual or the presented fat and energy content of a test dish eaten at lunch. Half of the subjects were classified as restrained and half as unrestrained eaters. The test dish was either 2473 kJ (591 kcal) in its high-fat version or 1485 kJ (355 kcal) in its low-fat version, and was provided either with a correct or incorrect information about its fat content. All the intakes at the three meals during the following 8 h were covertly recorded in the laboratory, and internal state rated on four occasions. After the low-fat test dish presented as low-fat, unrestrained eaters increased their energy intake compared to that in other conditions. Restrained subjects did not exhibit this pattern and compensated for the missing energy in the low-fat test dish, compared to the high-fat test dish, only when they were informed that both dishes were high in fat. Irrespective of the information, both restrained and unrestrained subjects reported weaker sensations of hunger after the actual high-fat test dish than after the actual low-fat test dish whereas only restrained eaters reported stronger sensations of fullness. Thus, the influence of the cognitive factors on food intake and ratings of internal state is modulated by restrained eating behaviour.

Adult↗

PubMed1995

Anatomic and physiologic heterogeneity in patients with syndrome X: an intravascular ultrasound study.

OBJECTIVES: We used intravascular ultrasound imaging of the epicardial vessels to assess coronary morphology, vasomotor response to exercise and exercise-vasomotion after beta-adrenoceptor blockade in patients with syndrome X. BACKGROUND: Syndrome X is defined as chest pain, abnormal exercise test results and normal coronary angiographic findings. Because of the limitations of coronary angiography, intravascular ultrasound was used to define coronary pathophysiology. METHODS: Thirty patients with syndrome X were studied with intravascular ultrasound imaging (30 MHz, 4.3F catheter) of all three major epicardial vessels. Supine arm exercise was performed during coronary imaging. Lumen area was assessed at rest and during peak exercise. The exercise-imaging protocol was repeated after loading with 0.1 mg/kg body weight of intravenous propranolol. RESULTS: Three morphologic groups were identified using intravascular ultrasound: normal coronary arteries (no plaque, intimal thickness < 0.25 mm, n = 12), atheromatous disease (mean [+/- SD] area stenosis 37.9 +/- 7.2%, n = 10) and marked intimal thickening (0.73 +/- 0.11 mm, n = 8). Patients with normal coronary arteries displayed a vasodilatory response to exercise (+16.9% area increase); patients with abnormal coronary arteries displayed a vasoconstrictive response to exercise (-17.4% in the group with plaque; -17.6% in the group with intimal thickening). Propranolol loading attenuated the vasodilatory response in the group with normal coronary arteries (+6.4% area increase) and attenuated the vasoconstrictive response in the two groups with abnormal coronary arteries (-8.0% in the group with plaque; -8.8% in the group with intimal thickening). CONCLUSIONS: Most patients with syndrome X have abnormal coronary arteries by intravascular ultrasound. Intravascular ultrasound identifies three distinct morphologic groups: normal coronary arteries, atheromatous plaque and intimal thickening. Exercise-vasomotion is normal in patients with syndrome X who have normal coronary arteries by ultrasound; patients with abnormal arteries (plaque or intimal thickening) have an abnormal (constrictive) response to exercise. Propranolol loading attenuates vasoreactivity in all subgroups, suggesting divergent therapeutic utility.

Analysis of Variance↗

PubMed1995

Effect of a covert fat dilution on the spontaneous food intake by lean and obese subjects.

Nine lean and nine obese subjects participated in two laboratory studies comparing the effects of a traditional high-fat dish (2.42 MJ and 49% as fat) and its convert fat-reduced version (1.53 MJ and 23% as fat) on subsequent food intake. Each version was consumed at the beginning of a free-choice lunch (experiment 1) or alone at lunch time (experiment 2). All subjects experienced both experiments. Three and 7 h after lunch, subjects were free to consume any of the items available in a vending machine. Food intake was measured directly. In experiment 1, by 8 h after lunch, mean cumulative energy intake (test dish included) was not different between the test dish conditions in both lean and obese subjects, and ad libitum energy intake (i.e. without test dish) was significantly higher under the low-fat than under the high-fat test dish condition. Thus, lean compensated 86% and obese 70% of the initial energy reduction. The cumulative fat intake (test dish included) was lower under the low-fat than under the high-fat dish condition for both weight groups. Nevertheless, the percentage of ad libitum energy intake derived from fat was significantly higher after the low-fat test dish in obese but not in lean subjects. In experiment 2, both weight groups maintained the energy and fat reduction. Thus, obese subjects did not respond differently to lean subjects to the fat and energy manipulation of the test dish, except for the percentage of fat in their diet. These results suggest that different ways of including fat-reduced foods into the habitual diet might have different effects on subsequent energy compensation.

Adult↗

PubMed1995

Lipoprotein lipase gene polymorphisms: associations with hypertriglyceridemia and body mass index in obese people.

OBJECTIVE: To compare body mass index (BMI), lipid, lipoprotein and apolipoprotein concentrations according to the Hind III and Pvu II restriction polymorphisms of the LPL gene in obese subjects. DESIGN: Cross sectional study of anthropometric and lipid variables in relation to genetic factors. SETTING: Nutrition Outpatient Clinic of Bichat Hospital in Paris, France. SUBJECTS: 236 unrelated patients (162 women and 74 men) were selected on the basis of 120% of ideal body weight. MAIN OUTCOME MEASURES: Anthropometry (body mass index, waist to hip ratio), blood lipids and lipoproteins, determination of LPL Hind III and Pvu II genotypes. RESULTS: Digestion with Hind III generated two alleles, H1 (absence of cutting site) and H2 (presence of cutting site), with frequencies of 0.30 and 0.70 respectively. Digestion with Pvu II generated two alleles P1 and P2 with frequencies of 0.49 and 0.51 respectively. The Hind III polymorphism was significantly associated with body mass index (BMI) (P < 0.05). The H2H2 genotype was associated with hypertriglyceridemia: 68% of the hypertriglyceridemic subjects have the H2H2 genotype vs 43% of the normotriglyceridemic group (P < 0.05). Plasma triglyceride levels varied significantly among the Hind III genotypes, H2H2 genotype having the highest total and VLDL-triglyceride levels; the Hind III polymorphism also showed a significant association with HDL2-cholesterol. These associations were only seen in women and were not explained by the variations in BMI and age. No significant associations were found between lipid traits and Pvu II genotype. CONCLUSION: These results suggest that genetic variation in the LPL gene in obese subjects is associated with hypertriglyceridemia and possibly with a predisposition to obesity.

Alleles↗

PubMed1995

Gastric distension, hunger and energy intake after balloon implantation in severe obesity.

OBJECTIVE: To investigate the interrelationships between satiety feelings, abdominal perception, energy intake and weight loss, related to the presence of an intragastric balloon. DESIGN: Randomized double blind study. SUBJECTS: 20 severely obese subjects, BMI > 40 kg/m2, randomly assigned either to receive an air filled balloon (n = 11) or to have a sham procedure (n = 9). All subjects had dietary counselling to help them follow a relatively low energy diet (60% of individual spontaneous intake). MEASUREMENTS: During biweekly visits, body weight was recorded, visual analogic scales for stomach distension, hunger and feeling of balloon presence were completed. Blood chemistry profiles were monitored once every 4 weeks. RESULTS: In the balloon group, the sensations related to the presence of the balloon and to abdominal distension dramatically increased after insertion, and plateaued during the next 4 weeks. Both feelings of presence and distension decreased thereafter, and after 10 weeks they were not significantly different from those of the sham balloon group. Hunger dramatically decreased to about 30% of initial rating in the first week, but slowly returned to the initial value by the 12th week. Hunger feelings were highly and negatively correlated with feelings of distension. During the same period, the sham balloon group continued to maintain the low energy intake, and did not register any feelings of distension or presence; hunger level did not differ from initial levels throughout the whole study. The energy intake and the rate of weight loss (8-9 kg) was similar in the two groups during the study, and were not correlated with the feelings of distension. CONCLUSION: This study showed that in severely obese subjects submitted to a restrictive diet, an intragastric balloon has a measurable but transient effect on the sensation of epigastric distension and is able to decrease feelings of hunger. Unfortunately, these effects were not associated with a lower energy intake or a higher rate of weight loss than the sham situation. Thus, the present study does not support the interest of such a balloon (500 ml, air filled) in the treatment of severe obesity.

Adult↗

PubMed1994

Palatability of a meal influences release of beta-endorphin, and of potential regulators of food intake in healthy human subjects.

The effect of the palatability of a meal was tested on the post-prandial release of several gut hormones or neuropeptides which are known to have an effect on intake and satiety. Hormonal response was determined in plasma during the 3 h after a highly palatable and energy-rich meal or after the same meal served cold in a poorly acceptable form, as well as while fasting. The early post-prandial pancreatic polypeptide and neurotensin response was significantly higher after the highly palatable meal than after the cold one. Later responses differed only for pancreatic polypeptide. No difference was observed in cholecystokinin and neuropeptide Y levels. Post-prandial levels of beta-endorphin were elevated only after the cold meal and were associated with an elevated response of ACTH. We suggest that beta-endorphin might be secreted in response to an aversion towards the non-palatable cold meal. This could, subsequently, inhibit the cephalic phase of pancreatic polypeptide response and the early post-prandial response of neurotensin by a central anticholinergic effect. This study evidences an effect of palatability on the modulation of the digestive hormonal response after a meal.

Adult↗

PubMed1994

Comparing the effects of aspartame and sucrose on motivational ratings, taste preferences, and energy intakes in humans.

This study compared the effects of four breakfast preloads on motivational ratings, taste preferences, and energy intakes of 24 normal-weight nondieting young men and women. The preloads, composed of creamy white cheese (fromage blanc), were either plain or sweetened with aspartame or sucrose. Their energy value was either 1255 or 2929 kJ (300 or 700 kcal). Taste preferences were measured before and 150 min after breakfast. Motivational ratings were obtained at 30-min intervals. The subjects ate lunch, snack, and dinner meals in the laboratory. The consumption of low-energy as opposed to high-energy breakfasts, regardless of sweetness, led to elevated motivational ratings and increased energy intakes at lunch. However, intakes at subsequent meals were the same for all preloads, and no overall compensation in energy was observed. Aspartame did not promote hunger or lead to increased energy intakes in normal-weight subjects.

Adult↗

PubMed1994

Effects of cycles of food restriction followed by ad libitum refeeding on body composition and energy expenditure in obese rats.

Male Wistar rats rendered obese by a cafeteria diet were subjected to three successive cycles alternating food restriction with ad libitum cafeteria-diet feeding (WC rats). Body composition, energy intake, energy required for maintenance, and oxygen consumption were studied. Results were compared with those for rats fed a standard stock diet (CON rats) or a cafeteria diet (CAF rats). The rate of weight loss or regain was independent of the number of cycles. WC rats were fatter than CON rats and as fat as CAF rats after the third cycle. Cost of maintenance of WC rats decreased; their oxygen consumption decreased in the lean state, increased again in the fat state, but remained lower than that of CON and CAF rats. We conclude that the practice of successive restriction and refeeding did not result in resistance to weight loss, but rather in a defect in the utilization of energy intake, facilitating the development of obesity.

Animals↗

PubMed1994

Mechanisms of decreased food intake during weight loss in adult Crohn's disease patients without obvious malabsorption.

Because weight loss is common in colonic Crohn's disease and is poorly correlated with disease activity, we analyzed food intake in 63 patients without malabsorption, 30 patients with weight loss (9.2 +/- 4.2 kg), and 33 patients without weight loss. Energy and protein intakes were lower in patients with weight loss than in those with stable weight (P < 0.01). In the former group, food restrictions were more numerous (P < 0.01) and visual analog scales showed less hunger, decreased appetite, and fewer sensations of pleasure related to eating, as compared with the other group (P < 0.01). Food intake reduction was also related to depressive mood and medical advice. However, there was no difference between groups in fecal energy wasting and resting energy expenditure. Weight loss in Crohn's disease may be due to a decrease in food intake rather than to an increase in energy cost of the disease. Thus, focus of attention on the diet is crucial to prevent malnutrition.

Adult↗

PubMed1994

Reproducible measurement of postprandial energy expenditure in young healthy males.

The reproducibility of measurements of postprandial energy expenditure (PEE) was determined by assessing, for 345 min, the diet-induced thermogenesis (DIT) of a 4055-kJ mixed meal in 10 lean young men on four occasions. The DIT was determined by using either a 20-min premeal baseline metabolic rate (method 1) or a single resting metabolic rate (RMR) measured on a separate day (method 2). The DIT, in kilojoules, for a given subject calculated by method 1 varied significantly between occasions, CV 15.4% (P < 0.05). The D peak (PEE peak minus baseline) did not vary significantly between the four trials (CV 13%). The results obtained by using method 2 were much more reproducible for both the DIT (CV 4.2%) and the D peak (CV 4.8%). Thus, the reproducibility of the PEE measurement is enhanced by using an RMR measured on a separate day and by using the postprandial peak value instead of the DIT.

Adult↗