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Biomedical subjects

F Xavier Pi-Sunyer

Publications and source records attributed to F Xavier Pi-Sunyer.

At least 19 recordsLinked to original sources
PubMed2007

Efficacy and tolerability of vildagliptin monotherapy in drug-naïve patients with type 2 diabetes.

UNLABELLED: This 24-week, double-blind, randomized, multicenter, placebo-controlled, parallel-group study performed in 354 drug-naïve patients with type 2 diabetes (T2DM) assessed efficacy and tolerability of vildagliptin (50mg qd, 50mg bid, or 100mg qd). The primary assessment was change from baseline to endpoint in hemoglobin A1c (A1C), comparing vildagliptin to placebo by ANCOVA. Baseline A1C averaged 8.4% and the between-treatment difference (vildagliptin-placebo) in adjusted mean change (AMDelta) in A1C was -0.5+/-0.2% (P=0.011), -0.7+/-0.2% (P<0.001), and -0.9+/-0.2% (P<0.001) in patients receiving vildagliptin 50 mg qd, 50 mg bid, or 100 mg qd, respectively. Baseline FPG averaged 10.5 mmol/L; the between-treatment difference in AMDelta FPG was -0.6+/-0.4 mmol/L in patients receiving vildagliptin 50mg qd and -1.3+/-0.4 mmol/L (P=0.001) in both groups receiving 100mg daily. Relative to baseline, body weight did not change significantly in any of the three vildagliptin groups and decreased by 1.4+/-0.4 kg in the placebo group. Adverse events (AEs) occurred with similar frequency in each group: 55.8%, 59.3%, 59.3%, and 57.6% of patients receiving vildagliptin 50 mg qd, 50 mg bid, 100 mg qd, or placebo, respectively, experienced an AE. No confirmed hypoglycemia was reported. CONCLUSION: Vildagliptin is effective and well-tolerated in drug-naïve patients with T2DM and 100 mg vildagliptin provides similar clinical benefit whether given as single or in divided doses.

Adamantane↗
PubMed2006

Metabolic inflexibility in substrate use is present in African-American but not Caucasian healthy, premenopausal, nondiabetic women.

CONTEXT: There is an increased prevalence of obesity and insulin resistance in African-American compared with Caucasian females. Metabolic inflexibility (MI) is the inability to switch the use of lipids and carbohydrates in the peripheral tissue (i.e. muscle) based upon substrate availability. OBJECTIVE: We examined whether MI exists in African-American females. MAIN OUTCOME MEASURES AND DESIGN: We measured substrate use differences during eucaloric, macronutrient-manipulated diets [high fat (50% fat, 35% carbohydrate, 15% protein) vs. low fat (30% fat, 55% carbohydrate, 15% protein)] between Caucasian and African-American women. We also compared differences in substrate use in response to insulin infusion during two-step pancreatic-euglycemic clamps and epinephrine infusion during lipolysis studies. In each study, similar groups of Caucasian and African-American women were compared. RESULTS: Caucasians had significantly higher fat oxidation (FO) (P = 0.01) and lower carbohydrate oxidation (P < 0.01) during the high-fat vs. low-fat diet, whereas no significant differences were observed in African-Americans. The African-American women also failed to significantly suppress FO during the second step of the pancreatic-euglycemic clamp despite a doubling of their fasting plasma insulin and failed to increase their FO or decrease their carbohydrate oxidation in response to epinephrine infusion as much as Caucasian women did. The response of free fatty acid turnover rates to insulin and epinephrine stimulation was similar between races. CONCLUSION: The impaired substrate use observed in African-American women during these three studies demonstrates the existence of MI and may contribute to their greater prevalence of obesity and insulin resistance.

Adult↗
PubMed2006

Effect of rimonabant, a cannabinoid-1 receptor blocker, on weight and cardiometabolic risk factors in overweight or obese patients: RIO-North America: a randomized controlled trial.

CONTEXT: Rimonabant, a selective cannabinoid-1 receptor blocker, may reduce body weight and improve cardiometabolic risk factors in patients who are overweight or obese. OBJECTIVE: To compare the efficacy and safety of rimonabant with placebo each in conjunction with diet and exercise for sustained changes in weight and cardiometabolic risk factors over 2 years. DESIGN, SETTING, AND PARTICIPANTS: Randomized, double-blind, placebo-controlled trial of 3045 obese (body mass index > or =30) or overweight (body mass index >27 and treated or untreated hypertension or dyslipidemia) adult patients at 64 US and 8 Canadian clinical research centers from August 2001 to April 2004. INTERVENTION: After a 4-week single-blind placebo plus diet (600 kcal/d deficit) run-in period, patients were randomized to receive placebo, 5 mg/d of rimonabant, or 20 mg/d of rimonabant for 1 year. Rimonabant-treated patients were rerandomized to receive placebo or continued to receive the same rimonabant dose while the placebo group continued to receive placebo during year 2. MAIN OUTCOME MEASURES: Body weight change over year 1 and prevention of weight regain during year 2. Additional efficacy measures included changes in waist circumference, plasma lipid levels, and other cardiometabolic risk factors. RESULTS: At year 1, the completion rate was 309 (51%) patients in the placebo group, 620 (51%) patients in the 5 mg of rimonabant group, and 673 (55%) patients in the 20 mg of rimonabant group. Compared with the placebo group, the 20 mg of rimonabant group produced greater mean (SEM) reductions in weight (-6.3 [0.2] kg vs -1.6 [0.2] kg; P<.001), waist circumference (-6.1 [0.2] cm vs -2.5 [0.3] cm; P<.001), and level of triglycerides (percentage change, -5.3 [1.2] vs 7.9 [2.0]; P<.001) and a greater increase in level of high-density lipoprotein cholesterol (percentage change, 12.6 [0.5] vs 5.4 [0.7]; P<.001). Patients who were switched from the 20 mg of rimonabant group to the placebo group during year 2 experienced weight regain while those who continued to receive 20 mg of rimonabant maintained their weight loss and favorable changes in cardiometabolic risk factors. Use of different imputation methods to account for the high rate of dropouts in all 3 groups yielded similar results. Rimonabant was generally well tolerated; the most common drug-related adverse event was nausea (11.2% for the 20 mg of rimonabant group vs 5.8% for the placebo group). CONCLUSIONS: In this multicenter trial, treatment with 20 mg/d of rimonabant plus diet for 2 years promoted modest but sustained reductions in weight and waist circumference and favorable changes in cardiometabolic risk factors. However, the trial was limited by a high drop-out rate and longer-term effects of the drug require further study. Clinical Trials Registration ClinicalTrials.gov Identifier: NCT00029861.

Adult↗
PubMed2006

Serum iron and body fat distribution in a multiethnic cohort of adults living in New York City.

OBJECTIVE: To examine the relationship between serum iron and body composition in a multiracial adult cohort. METHODS: The analysis consisted of 670 participants on whom blood analysis and anthropometric data were available. The participants were recruited as part of the Rosetta Study (1990-2000), which was designed to assess body composition in a multiethnic cohort of healthy adults. Fasting iron level was measured as part of a biochemistry panel. Dual x-ray absorptiometry was used to assess fat mass. Anthropometric measures included waist circumference and body mass index (BMI; calculated as kg/m(2)) as an index of abdominal adiposity and overall body fatness, respectively. RESULTS: In the study cohort the mean age was 54+/-17 years and 60.9% were overweight or obese (BMI > or =25). Men had higher serum iron levels (94.91+/-34.52 microg/dL [16.99+/-6.18 micromol/L] vs 82.17+/-32.62 microg/dL [14.71+/-5.84 micromol/L]) and larger waist circumference (91.98+/-11.87 cm vs 85.24+/-12.37 cm) compared with women (P<0.001). Iron was inversely correlated with BMI (r=-0.23, P<0.001), waist circumference (r=-0.19, P<0.05), and fat mass (r=-0.19, P<0.05) among Hispanic women but not among African-American, white, or Asian women or in men of any race/ethnic group. CONCLUSIONS: The results of this study show an inverse association of measures of body fat distribution and total fat mass with serum iron level in Hispanic women. Studies designed to explore how micronutrients are used by the body at varying degrees of body fatness could provide useful information on the micronutrient-related comorbidities of obesity.

Abdominal Fat↗
PubMed2006

The relation of adipose tissue to cardiometabolic risk.

Adipose tissue is an active and complex endocrine organ that secretes numerous bioactive substances, including hormones, growth factors, and cytokines. Central obesity, one of the components of metabolic syndrome, is a cardiometabolic risk factor associated with a state of chronic inflammation and coagulation, one in which the expression of certain adipocytokines, including tumor necrosis factor-alpha (TNF-(alpha), interleukin (IL)-6, and plasminogen activator inhibitor-1 (PAI-1) is more abundantly increased, while adiponectin expression is decreased. TNF-alpha initiates and organizes inflammatory changes in vascular tissue. IL-6, an inflammatory cytokine directly implicated in atherogenesis, exerts pleiotropic effects on a variety of tissues. An increased concentration of PAI-1, an important regulator of the endogenous fibrinolytic system, promotes continued clotting. Adiponectin, on the other hand, has potent vasculoprotective, angiogenic, anti-inflammatory, and antiatherogenic properties. Adiponectin levels are low in obese individuals and increase when weight is lost, thereby serving as a marker for cardioprotection. Weight loss has long been promoted as a means to reduce the risk of type 2 diabetes and cardiovascular disease; for example, exercise and a hypocaloric diet have been shown to decrease PAI-1 levels. Weight loss drugs, such as orlistat, a lipase inhibitor, and sibutramine, a serotonin and norepinephrine reuptake inhibitor, have both been shown to produce a decrease in C-reactive protein levels and an increase in serum adiponectin. Rimonabant, a selective cannabinoid 1 receptor antagonist in Phase III studies, also has been shown to increase adiponectin levels. These agents may play a role in the regulation of adipocytokines, which may directly affect the risk for cardiometabolic disease.

Adipocytes↗
PubMed2006

Use of lifestyle changes treatment plans and drug therapy in controlling cardiovascular and metabolic risk factors.

Intervention in weight management should begin before the onset of the metabolic syndrome. Therapeutic lifestyle changes (e.g., diet and physical activity) comprise the cornerstone of care for overweight and obese patients. Behavior modification approaches are useful in facilitating adherence to specific dietary regimens. Pharmacotherapy is an option for patients with a BMI >30 kg/m(2) or for those with a BMI of 27 to 30 kg/m(2) and two or more risk factors, who have failed on diet and exercise alone. To date, the U.S. Food and Drug Administration has approved three weight loss agents: sibutramine, orlistat, and phentermine.

Caloric Restriction↗
PubMed2006

Serum magnesium and type-2 diabetes in African Americans and Hispanics: a New York cohort.

OBJECTIVES: The aim of this study was to examine the relationship of serum Mg with stage of diabetes measured by fasting serum glucose in a cohort of 485 African American and Hispanic adults. METHODS: The cross sectional Rosetta study was designed to assess body composition in a multi-racial cohort of healthy adults living in New York City. The data utilized for the current analyses were collected during the years 1990 to 2000. Serum Mg and glucose were measured after a 10-12 hour fast. Dual-energy x-ray absorptiometry was used to measure fat mass (FM) and fat free mass (FFM). RESULTS: The mean age of the cohort was 53 +/- 16 years. Hispanics had significantly lower (p < 0.05) mean serum Mg levels (0.82 +/- 0.07 mmol/L vs. 0.85 +/- 0.07 mmol/L) and FFM (48.8 +/- 10.9 kg vs. 50.9 +/- 10.3 kg) compared to African Americans. In both race/ethnic groups, individuals classified as having diabetes had significantly (p < 0.001) lower serum concentrations of Mg (0.80 +/- 0.07 mmol/L) compared to the normal group (0.84 +/- 0.07 mmol/L). CONCLUSIONS: These results show that in African American and Hispanic adults, those with diabetes have lower serum Mg levels compared to those classified as pre-diabetic or those with normal fasting glucose levels.

Adipose Tissue↗
PubMed2006

Validation of a 3-dimensional photonic scanner for the measurement of body volumes, dimensions, and percentage body fat.

BACKGROUND: The 3-dimensional photonic scan (3DPS) technique has been used during the past decade in the fashion industry and for epidemiologic surveys to estimate human body sizes. OBJECTIVE: The objective of the study was to validate the accuracy of a recently developed 3DPS (C9036-02; Hamamatsu Photonics KK, Hamamatsu, Japan) for the measurement of body volume, circumferences, lengths, and percentage body fat with the use of underwater weighing (UWW) and tape measures as criterion methods. DESIGN: Ninety-two subjects (44 females and 48 males) aged 6-83 y and weighing 23-182 kg (52-400 lbs) participated in the study. The subjects were measured while they wore minimal clothing and a head cap. Similar measurements were performed on a mannequin with and without clothing RESULTS: All subjects were measured with 3DPS and a tape measure; 63 subjects underwent UWW and residual lung volume measurements. The values obtained with 3DPS were slightly but significantly greater than those obtained with UWW for body volume (81.9 +/- 4.0 L compared with 81.5 +/- 4.0 L, P < 0.0001) and those obtained with a tape measure for circumferences (P < 0.001), but the values for percentage body fat were not significantly different between 3DPS and UWW (P = 0.648). The values obtained with 3DPS were significantly greater than those obtained by UWW and a tape measure for the clothed mannequin, but the values were not uniformly significantly different for the mannequin without clothing. CONCLUSIONS: The 3DPS measures body volume, circumferences, and length rapidly and accurately. However, to generate an accurate total-body volume measurement with 3DPS to estimate percentage body fat, the subjects must wear close-fitting minimal clothing and be able to stand motionless for 10 s (normal scan mode) while holding their breath, which is done immediately after a maximum expiration.

Adipose Tissue↗
PubMed2006

Obesity and cardiovascular disease: pathophysiology, evaluation, and effect of weight loss.

Obesity is becoming a global epidemic in both children and adults, and it is associated with numerous co-morbidities such as cardiovascular diseases (CVD), type 2 diabetes, hypertension, certain cancers, and sleep apnea/sleep-disordered breathing. In fact, is an independent risk factor for CVD and CVD risks have been also documented in obese children, and is associated with reduced life expectancy. A variety of adaptations/alterations in cardiac structure and function occur in the individual as adipose tissue accumulates in excess amount. As a whole, overweight/obesity predispose or is associated with numerous cardiac complications such as coronary heart disease, heart failure, and sudden death through its impact on the cardiovascular system.

Arrhythmias, Cardiac↗
PubMed2005

Obesity and cardiovascular disease: pathophysiology, evaluation, and effect of weight loss: an update of the 1997 American Heart Association Scientific Statement on Obesity and Heart Disease from the Obesity Committee of the Council on Nutrition, Physical Activity, and Metabolism.

Obesity is becoming a global epidemic in both children and adults. It is associated with numerous comorbidities such as cardiovascular diseases (CVD), type 2 diabetes, hypertension, certain cancers, and sleep apnea/sleep-disordered breathing. In fact, obesity is an independent risk factor for CVD, and CVD risks have also been documented in obese children. Obesity is associated with an increased risk of morbidity and mortality as well as reduced life expectancy. Health service use and medical costs associated with obesity and related diseases have risen dramatically and are expected to continue to rise. Besides an altered metabolic profile, a variety of adaptations/alterations in cardiac structure and function occur in the individual as adipose tissue accumulates in excess amounts, even in the absence of comorbidities. Hence, obesity may affect the heart through its influence on known risk factors such as dyslipidemia, hypertension, glucose intolerance, inflammatory markers, obstructive sleep apnea/hypoventilation, and the prothrombotic state, in addition to as-yet-unrecognized mechanisms. On the whole, overweight and obesity predispose to or are associated with numerous cardiac complications such as coronary heart disease, heart failure, and sudden death because of their impact on the cardiovascular system. The pathophysiology of these entities that are linked to obesity will be discussed. However, the cardiovascular clinical evaluation of obese patients may be limited because of the morphology of the individual. In this statement, we review the available evidence of the impact of obesity on CVD with emphasis on the evaluation of cardiac structure and function in obese patients and the effect of weight loss on the cardiovascular system.

American Heart Association↗
PubMed2005

Korean and Caucasian overweight premenopausal women have different relationship of body mass index to percent body fat with age.

The aim of the study was to investigate in premenopausal women whether the relationship between percentage body fat (PBF) and body mass index (BMI; in kg/m2) differs between Korean Asians (Ko-As) living in Seoul, South Korea, and Caucasians (Ca) living in New York City. Healthy premenopausal women (50 Ko-As; 38 Ca), ages 22-50 yr, were studied. Weight, height, and PBF by dual-energy X-ray absorptiometry were measured. Total body dual-energy X-ray absorptiometry data were collected using GE-Lunar systems (Prodigy-Korea and DPXL-New York), and all scan analyses were performed by one technician in New York. Similar soft tissue phantoms were used for daily instrument calibrations at both sites. The relationship between PBF and BMI was assessed by multiple regression analysis with race, age, reciprocal of BMI (1/BMI), and a race-by-age interaction as the final independent variables. Race (P = 0.003) and 1/BMI (P < 0.001) were significantly related to PBF in this model. A significant race-by-age interaction (P = 0.039) indicated that the slope of the lines for PBF vs. age differed between Ko-As and Ca. This study demonstrates in a Ko-As sample that the BMI-fat relationship differs significantly from that in a comparable group of Caucasian women. Investigators who use BMI as an index of fatness should be aware of the well documented differences in the relationship of BMI and fatness across race/ethnic groups.

Adipose Tissue↗
PubMed2005

Assessment of human locomotion by using an insole measurement system and artificial neural networks.

A new method for measuring and characterizing free-living human locomotion is presented. A portable device was developed to objectively record and measure foot-ground contact information in every step for up to 24h. An artificial neural network (ANN) was developed to identify the type and intensity of locomotion. Forty subjects participated in the study. The subjects performed level walking, running, ascending and descending stairs at slow, normal and fast speeds determined by each subject, respectively. The device correctly identified walking, running, ascending and descending stairs (accuracy 98.78%, 98.33%, 97.33%, and 97.29% respectively) among different types of activities. It was also able to determine the speed of walking and running. The correlation between actual speed and estimated speed is 0.98, p< 0.0001. The average error of walking and running speed estimation is -0.050+/-0.747 km/h (mean +/- standard deviation). The study has shown the measurement of duration, frequency, type, and intensity of locomotion highly accurate using the new device and an ANN. It provides an alternative tool to the use of a gait lab to quantitatively study locomotion with high accuracy via a small, light and portable device, and to do so under free-living conditions for the clinical applications.

Adolescent↗
PubMed2005

Intentional weight loss reduces mortality rate in a rodent model of dietary obesity.

OBJECTIVE: We used a rodent model of dietary obesity to evaluate effects of caloric restriction-induced weight loss on mortality rate. Research Measures and Procedures: In a randomized parallel-groups design, 312 outbred Sprague-Dawley rats (one-half males) were assigned at age 10 weeks to one of three diets: low fat (LF; 18.7% calories as fat) with caloric intake adjusted to maintain body weight 10% below that for ad libitum (AL)-fed rat food, high fat (HF; 45% calories as fat) fed at the same level, or HF fed AL. At age 46 weeks, the lightest one-third of the AL group was discarded to ensure a more obese group; the remaining animals were randomly assigned to one of three diets: HF-AL, HF with energy restricted to produce body weights of animals restricted on the HF diet throughout life, or LF with energy restricted to produce the body weights of animals restricted on the LF diet throughout life. Life span, body weight, and leptin levels were measured. RESULTS: Animals restricted throughout life lived the longest (p < 0.001). Life span was not different among animals that had been obese and then lost weight and animals that had been nonobese throughout life (p = 0.18). Animals that were obese and lost weight lived substantially longer than animals that remained obese throughout life (p = 0.002). Diet composition had no effect on life span (p = 0.52). DISCUSSION: Weight loss after the onset of obesity during adulthood leads to a substantial increase in longevity in rats.

Aging↗
PubMed2005

Physical disability and obesity.

Nearly 20% of US citizens are disabled. Epidemiologic studies have shown that people with physical disabilities have a 1.2- to 3.9-fold increase in obesity prevalence. Obesity is becoming a serious problem in disabled individuals. The mechanisms by which obesity occurs in people with physical disabilities is not clear, but pathophysiological changes of body composition and energy metabolism, physical inactivity, and muscle atrophy all favor the development of obesity. Health professionals should identify disabled patients at risk and provide early prevention guidance. Research is needed to help generate detailed clinical guidelines to promote weight control among people with physical disabilities.

Body Composition↗