bluuebunny/crossref_metadata_2025 huggingface dataset:
Neural Mechanisms Underlying Hyperphagia in Prader‐Willi Syndrome
Authors: Holsen Laura M. , Zarcone Jennifer R. , Brooks William M. , Butler Merlin G. , Thompson Travis I. , Ahluwalia Jasjit S. , Nollen Nicole L. , Savage Cary R.
Published: April 2008

Objective: Prader‐Willi syndrome (PWS) is a genetic disorder associated with developmental delay, obesity, and obsessive behavior related to food consumption. The most striking symptom of PWS is hyperphagia; as such, PWS may provide important insights into factors leading to overeating and obesity in the general population. We used functional magnetic resonance imaging to study the neural mechanisms underlying responses to visual food stimuli, before and after eating, in individuals with PWS and a healthy weight control (HWC) group.

Research Methods and Procedures: Participants were scanned once before (pre‐meal) and once after (post‐meal) eating a standardized meal. Pictures of food, animals, and blurred control images were presented in a block design format during acquisition of functional magnetic resonance imaging data.

Results: Statistical contrasts in the HWC group showed greater activation to food pictures in the pre‐meal condition compared with the post‐meal condition in the amygdala, orbitofrontal cortex, medial prefrontal cortex (medial PFC), and frontal operculum. In comparison, the PWS group exhibited greater activation to food pictures in the post‐meal condition compared with the pre‐meal condition in the orbitofrontal cortex, medial PFC, insula, hippocampus, and parahippocampal gyrus. Between‐group contrasts in the pre‐ and post‐meal conditions confirmed group differences, with the PWS group showing greater activation than the HWC group after the meal in food motivation networks.

Discussion: Results point to distinct neural mechanisms associated with hyperphagia in PWS. After eating a meal, the PWS group showed hyperfunction in limbic and paralimbic regions that drive eating behavior (e.g., the amygdala) and in regions that suppress food intake (e.g., the medial PFC).
Obese Subjects Respond to the Stimulatory Effect of the Ghrelin Agonist Growth Hormone‐Releasing Peptide‐2 on Food Intake
Authors: Laferrère Blandine , Hart Allison B. , Bowers Cyril Y.
Published: April 2008

Objective: The administration of the growth hormone (GH) secretagogue GH‐releasing peptide (GHRP)‐2, like ghrelin, increases food intake (FI) in lean healthy men. The aim of this study was to investigate whether this effect occurs in obese subjects and whether it is dose‐dependent.

Research Methods and Procedures: Nineteen subjects (10 lean and nine obese), all healthy and weight stable, received a double‐blind randomized subcutaneous infusion of GHRP‐2 at high dose (HD; 1 μg/kg per hour), low dose (0.1 μg/kg per hour), or placebo for 270 minutes over three study visits. Blood for hormone assays was collected through an intravenous forearm catheter. Hunger and fullness were rated on visual analog scales before and after a fixed breakfast (320 kcal at 120 minutes) and a buffet lunch at 240 minutes. Before lunch, subjects received taped instructions to eat as much as they wanted.

Results: GHRP‐2 infusion significantly increased ad libitum FI in a dose‐dependent manner by 10.2 ± 3.9% at low dose (p = 0.011) and by 33.5 ± 5.8% at HD (p = 0.000) compared with placebo. Obesity status did not influence the effect of GHRP‐2 on FI. All subjects had greater ratings of appetite before but similar levels of fullness after the meal with the HD GHRP‐2. Serum GH levels increased dose dependently in all subjects.

Discussion: The dual stimulatory effect of GHRP‐2 on FI and human GH is dose dependent. Obese individuals retain their ability to respond to GHRP‐2 both in terms of FI and human GH.
Lifestyle Intervention in Obese Patients with Type 2 Diabetes: Impact of the Patient's Educational Background
Authors: Gurka Matthew J. , Wolf Anne M. , Conaway Mark R. , Crowther Jayne Q. , Nadler Jerry L. , Bovbjerg Viktor E.
Published: April 2008

Objective: To determine whether people with different educational backgrounds respond differently to a lifestyle intervention program for obese patients with type 2 diabetes.

Research Methods and Procedures: The study consisted of a 12‐month randomized controlled trial of 147 health plan members with type 2 diabetes who were overweight or obese (BMI ≥ 27 kg/m2). Participants were randomized to lifestyle case management or usual care. Case management (CM) involved group and individual education, support, and referral by registered dietitians. Usual care (UC) participants received educational material. Both groups received ongoing primary care. A post hoc analysis was performed, evaluating the impact of education level on intervention group differences with respect to change in weight and waist circumference.

Results: There was a significant education by group interaction for both changes in weight (p = 0.02) and waist circumference (p = 0.01) during the study period. Contrary to expectations, CM participants with less formal education had greater risk reductions compared with more educated participants. Models predicted that, by 12 months, those with less education in the UC group gained 1.71 kg more in weight and 3.67 cm more in waist circumference than those with greater education. However, by 12 months, those in the CM group with less education lost a model‐predicted 3.30 kg more in weight and 4.95 cm more in waist circumference than those with more formal education.

Discussion: People with varied educational backgrounds may respond differently to a lifestyle intervention for weight management and diabetes control.
Energy Restriction with Different Protein Quantities and Source: Implications for Innate Immunity
Authors: McFarlin Brian K. , Flynn Michael G. , Mahon Anne K. , Stewart Laura K. , Timmerman Kyle L. , Lyle Roseann M. , Campbell Wayne W.
Published: April 2008

Objective: Physical age, energy restriction (ER), and weight loss have been reported to suppress indices of innate immunity, which may increase the risk of illness. To evaluate these interactions, we recruited older, postmenopausal women (50 to 80 years) to fill one of the following 9‐week ER (1250 kcal/d) groups: beef [n = 14; reported intakes 46% carbohydrate (CHO):24% protein (PRO):30% fat], chicken (n = 15; 51% CHO:25% PRO:24% fat), or CHO (n = 14; 59% CHO:17% PRO:24% fat), or a non‐intervention control (n = 11).

Research Methods and Procedures: Fasting blood was collected before and after ER to determine leukocyte phenotype, neutrophil oxidative burst capacity, natural killer cell activity, stimulated interleukin‐2 and interferon‐γ production, and blood zinc and iron concentrations.

Results: No significant effects of ER (8.6% weight loss) or PRO quantity and source were found for the majority of indices of innate immunity. Small but significant (p < 0.05) declines in interleukin‐2 production were found in the chicken and CHO groups only; however, the clinical significance of this finding is not known.

Discussion: In the present study, 9 weeks of moderate ER did not suppress immunity in postmenopausal women. Also, contrary to our hypothesis, differential zinc and iron intakes did not significantly alter immunity.
Changes in Food Cravings during Low‐Calorie and Very‐Low‐Calorie Diets
Authors: Martin Corby K. , O'Neil Patrick M. , Pawlow Laura
Published: April 2008

Objective: This study examined food cravings during a primarily food‐based low‐calorie diet (LCD) and a supplement‐based very‐LCD (VLCD).

Research Methods and Procedures: The Food Craving Inventory (FCI) was used to measure general cravings and cravings for specific types of foods (sweets, high fats, carbohydrates/starches, and fast food fats). The FCI was completed by participants in the LCD and VLCD programs at baseline and after 11 weeks of dieting. The VLCD group also completed the FCI at Week 6 and after 5 weeks of a refeeding phase, when their diet consisted primarily of solid food.

Results: From baseline to Week 12, craving decreases were greater for the VLCD group than for the LCD group on all measures. All craving measures decreased significantly for the VLCD group. The LCD group experienced a marginally significant decrease in sweet cravings. Within the VLCD group, all craving measures decreased significantly by Week 6 and did not change thereafter, including after resumption of solid food intake, and craving scores during all dieting points were lower than baseline. Changes in cravings were not related to weight loss.

Discussion: Cravings did not increase during either diet; all changes represented decreases. Compared with a primarily food‐based diet (LCD), a more restrictive supplement‐based diet (VLCD) resulted in significantly larger decreases in food cravings that occurred by the end of the 5th week of supplement use and did not rebound with resumption of solid food intake. The results of this study suggest that food cravings diminish with calorie restriction.
Two‐Year Internet‐Based Randomized Controlled Trial for Weight Loss in African‐American Girls
Authors: Williamson Donald A. , Walden Heather M. , White Marney A. , York‐Crowe Emily , Newton Robert L. , Alfonso Anthony , Gordon Stewart , Ryan Donna
Published: April 2008

Objective: A randomized controlled trial tested the efficacy of an internet‐based lifestyle behavior modification program for African‐American girls over a 2‐year period of intervention.

Research Methods and Procedures: Fifty‐seven overweight (mean BMI percentile, 98.3) African‐American girls (mean age, 13.2 years) were randomly assigned to an interactive behavioral internet program or an internet health education program, the control condition. Overweight parents were also participants in the study. Forty adolescent‐parent dyads (70%) completed the 2‐year trial. Outcome data including BMI, body weight, body composition, and weight loss behaviors were collected at baseline and at 6‐month intervals. A computer server tracked use of the web sites.

Results: An intention‐to‐treat statistical approach was used, with the last observation carried forward. In comparison with the control condition, adolescents in the behavioral program lost more mean body fat (BF) (−1.12 ± 0.47% vs. 0.43 ± 0.47% BF, p < 0.05), and parents in the behavioral program lost significantly more mean body weight (−2.43 ± 0.66 vs. −0.35 ± 0.64 kg, p < 0.05) during the first 6 months. This weight loss was regained over the next 18 months. After 2 years, differences in fat for adolescents (−0.08 ± 0.71% vs. 0.84 ± 0.72% BF) and weight for parents (−1.1 ± 0.91 vs. −0.60 ± 0.89 kg) did not differ between the behavioral and control programs.

Discussion: An internet‐based weight management program for African‐American adolescent girls and their parents resulted in weight loss during the first 6 months but did not yield long‐term loss due to reduced use of the web site over time.
Fasting‐based Estimates of Insulin Sensitivity in Overweight and Obesity: A Critical Appraisal
Authors: Ruige Johannes B. , Mertens Ilse L. , Bartholomeeusen Ellen , Dirinck Eveline , Ferrannini Ele , Van Gaal Luc F.
Published: April 2008

Objective: To identify simple methods to estimate the degree of insulin resistance.

Research Methods and Procedures: The performance of a wide range of fasting‐based index estimates of insulin sensitivity was compared by receiver operating characteristic analysis (area under curves and their 95% confidence intervals) against the M value from euglycemic insulin clamp studies collected in the San Antonio (non‐Hispanic whites and Hispanic residents of San Antonio, TX) and European Group for the Study of Insulin Resistance (non‐diabetic white Europeans) databases (n = 638).

Results: Insulin resistance differed substantially between lean (BMI < 25 kg/m2), overweight or obese (BMI ≥ 25 kg/m2), and type 2 diabetic individuals. Estimates of insulin resistance were, therefore, assessed in each group separately. In the overweight and obese subgroup (n = 302), the receiver operating characteristic performance of fasting‐based indices varied from 0.72 (0.62 to 0.82), in the case of the insulin/glucose ratio, to 0.80 (0.72 to 0.88) in the case of Belfiore free fatty acids. One superior method could not be identified; the confidence intervals overlapped, and no statistically significant differences emerged. All indices performed better when using the whole study population, with fasting plasma insulin, homeostatic model assessment, insulin/glucose ratio, quantitative insulin sensitivity check index, glucose/insulin ratio, Belfiore glycemia, revised quantitative insulin sensitivity check index, McAuley index, and Belfiore free fatty acids showing area under curves of 0.83, 0.90, 0.66, 0.90, 0.66, 0.90, 0.85, 0.83, and 0.86, respectively, because of the inclusion of very insulin sensitive (lean) and very insulin resistant cases (diabetic subjects).

Discussion: In conclusion, a superior fasting‐based index estimate to distinguish between the presence and absence of insulin resistance in overweight and obesity could not be identified despite the use of the large datasets.
BMI Modifies Associations of IL‐6 Genotypes with Insulin Resistance: The Framingham Study
Authors: Herbert Alan , Liu Chunyu , Karamohamed Samer , Liu Jun , Manning Alisa , Fox Caroline S. , Meigs James B. , Cupples L. Adrienne
Published: April 2008

Objective: The −174 interleukin (IL)‐6 gene polymorphism has been proposed as a risk factor for type 2 diabetes, but data are conflicting. Because white fat is a major source of IL‐6 in resting individuals, we tested the hypothesis that BMI modifies the association among the IL‐6 genotype, insulin resistance (IR) (measured using the homeostasis model), and risk of diabetes.

Research Methods and Procedures: Outcomes were assessed in a community‐based cohort study of 1525 adults (mean age, 55.6 years; 753 men), who participated in the Framingham Offspring Study during the 1991 to 1995 examinations.

Results: We found a significant interaction between IL‐6 genotype and BMI on levels of IR in men (p < 0.0001), with obese homozygotes for the minor C allele being most resistant. The IL‐6‐BMI interaction was not significant (p = 0.46) in women. Among men with the CC genotype, increasing BMI was associated with increased prevalence of diabetes [odds ratio (OR) per unit increase in BMI, 1.30; 95% confidence interval (CI), 1.11 to 1.50] but not among those with the GG (OR, 1.10; 95% CI, 0.98 to 1.22) or GC genotype (OR, 1.05; 95% CI, 0.97 to 1.14).

Discussion: The −174 IL‐6 promoter polymorphism modifies the association of obesity with IR and diabetes risk in men. Weight loss regimens targeted at reducing the risk of diabetes may be of particular benefit for men with a −174 IL‐6 CC genotype.
Midlife Obesity and Long‐Term Risk of Nursing Home Admission
Authors: Elkins Jacob S. , Whitmer Rachel A. , Sidney Stephen , Sorel Mike , Yaffe Kristine , Johnston S. Claiborne
Published: April 2008

Objective: Obesity is a growing problem among middle‐aged individuals. We investigated whether obesity in middle‐aged individuals influences the need for future nursing home care and whether the risk of nursing home admission associated with obesity is greater in whites than in blacks.

Research Methods and Procedures: The study population (N = 8804) consisted of long‐term members of the Kaiser Permanente Medical Care Plan ages 75 to 85 years in 1995 who had completed a standardized, multiphasic health checkup while in their 50s. The multiphasic health checkup examinations were performed as part of routine medical care between the years 1964 and 1973 and included standardized measurements of BMI. We used health plan records to assess incident nursing home admissions from 1995 to 2002. The risk of nursing home admission associated with standard categories of midlife BMI was estimated using Cox proportional hazard analysis.

Results: During an average follow‐up of 5.1 years, the nursing home admission rate was 6.8 per 100 person‐years of observation. After adjustment for comorbidities, midlife obesity predicted incident nursing home admission ∼25 years later [hazard ratio (HR), 1.30; 95% confidence interval (CI), 1.15 to 1.46; p < 0.001]. Overweight BMI at midlife was not associated with future nursing home admission (HR, 1.05; 95% CI, 0.97 to 1.14; p = 0.23). The risk of nursing home admission associated with midlife obesity was higher in whites (HR, 1.34; 95% CI, 1.17 to 1.54; p < 0.001) than in blacks (HR 1.15; 95% CI, 0.87 to 1.52; p = 0.32), but the difference between races was not significant (p for interaction = 0.65).

Discussion: Obesity among middle‐aged individuals is associated with an increased risk of nursing home admission in late life and may be an important target for reducing the future societal burden of nursing home care.
Night Eating: Prevalence and Demographic Correlates
Authors: Striegel‐Moore Ruth H. , Franko Debra L. , Thompson Douglas , Affenito Sandra , Kraemer Helena C.
Published: April 2008

Objective: To examine the prevalence and correlates of night eating, the core behavioral symptom of night eating syndrome among adolescents and adults, using two public access survey databases of nationally representative samples.

Research Methods and Procedures: Data were extracted for individuals age 13 years or older who completed food diary data for the National Health and Nutrition Examination Survey III (N = 18, 407) or the Continuing Survey of Food Intakes by Individuals (N = 10, 741). Prevalence estimates were calculated for three commonly used definitions of night eating. Logistic regression was used to examine correlates of night eating: type of day, season, gender, age, race/ethnicity, and BMI or obesity.

Results: With few exceptions, findings were similar in the two surveys. Night eating is most common during the weekend; prevalence is greatest among young adults (18 to 30 years of age) and least common among individuals age 65 years or older; and is not associated with BMI or obesity. Gender or ethnicity effects were not found to be stable across surveys.

Discussion: Experts need to consider type of day, age group, and possibly gender and race/ethnicity when examining population differences in night eating. Longitudinal studies are needed to further examine the link between night eating and obesity.
The Promoter Region of the Adiponectin Gene Is a Determinant in Modulating Insulin Sensitivity in Childhood Obesity
Authors: Petrone Antonio , Zavarella Sara , Caiazzo Assunta , Leto Gaetano , Spoletini Marialuisa , Potenziani Stella , Osborn John , Vania Andrea , Buzzetti Raffaella
Published: April 2008

We investigated the association of the −11,391G>A, −11,377G>C, +45T>G, and +276G>T adiponectin single‐nucleotide polymorphisms (SNPs) and expected haplotypes with the insulin resistance (IR) state in overweight/obese children; by using the haplotype background analysis, we also assessed the effect of each SNP independently. GG genotype at the −11,391 locus was associated with higher fasting insulin levels and homeostasis model assessment‐IR index and lower adiponectin levels compared with GA + AA genotypes (p = 0.01, 0.002, and 0.03, respectively). Those heterozygous and homozygous for G allele at the −11,377 locus showed higher fasting glucose (p = 0.001 for both), fasting insulin (p = 0.001 for both), homeostasis model assessment‐IR index (p < 0.001 for both), and triglyceride levels (p = 0.02 and 0.03, respectively) and lower adiponectin levels (p = 0.002 and 0.02, respectively) compared with C homozygotes. The +45G carriers showed higher fasting and 2‐hour glucose levels (p = 0.01 for both) and lower adiponectin levels (p = 0.02) compared with non‐carriers. Haplotype analysis suggested that, considering the same haplotypic background, each of the three polymorphisms exerted an independent effect on investigated parameters. The −11,391G>A, −11,377C>G, and +45T>G SNPs are associated with IR syndrome in overweight/obese children; they independently influence the investigated variables. The effect of +45T>G SNP seems to be marginal compared with the promoter SNPs. The GGT haplotype is associated with the highest degree of IR.
11β‐Hydroxysteroid Dehydrogenase Type 1 in Adipose Tissue and Prospective Changes in Body Weight and Insulin Resistance
Authors: Koska Juraj , De Courten Barbora , Wake Deborah J. , Nair Saraswathy , Walker Brian R. , Bunt Joy C. , Permana Paska A. , Lindsay Robert S. , Tataranni P. Antonio
Published: April 2008

Objective: Increased mRNA and activity levels of 11β‐hydroxysteroid dehydrogenase type 1 (11βHSD1) in human adipose tissue (AT) are associated with obesity and insulin resistance. The aim of our study was to investigate whether 11βHSD1 expression or activity in abdominal subcutaneous AT of non‐diabetic subjects are associated with subsequent changes in body weight and insulin resistance [homeostasis model assessment of insulin resistance (HOMA‐IR)].

Research Methods and Procedures: Prospective analyses were performed in 20 subjects (two whites and 18 Pima Indians) who had baseline measurements of 11βHSD1 mRNA and activity in whole AT (follow‐up, 0.3 to 4.9 years) and in 47 Pima Indians who had baseline assessments of 11βHSD1 mRNA in isolated adipocytes (follow‐up, 0.8 to 5.3 years).

Results: In whole AT, although 11βHSD1 mRNA levels showed positive associations with changes in weight and HOMA‐IR, 11βHSD1 activity was associated with changes in HOMA‐IR but not in body weight. 11βHSD1 mRNA levels in isolated adipocytes were not associated with follow‐up changes in any of the anthropometric or metabolic variables.

Discussion: Our results indicate that increased expression of 11βHSD1 in subcutaneous abdominal AT may contribute to risk of worsening obesity and insulin resistance. This prospective relationship does not seem to be mediated by increased 11βHSD1 expression in adipocytes.
Thermoregulatory Control of Feeding and Sleep in Premature Infants
Authors: Chardon Karen , Cardot Virginie , Léké André , Delanaud Stéphane , Bach Véronique , Dewasmes Gérard , Telliez Frédéric
Published: April 2008

Objective: The aim of the present study was to test the thermoregulatory feeding control hypothesis in sleeping, premature infants.

Research Methods and Procedures: In premature infants, the energy supply from food intake is crucial for (in order of importance): organ operation, body homeothermia, and optimal growth. The Himms‐Hagen model of thermoregulatory feeding control involving activation of heat production by brown adipose tissue (BAT) was formulated on the basis of work in (awake) rats. This hypothesis has also been put forward for the human neonate, which can also use BAT to produce metabolic heat. According to the model, feeding episodes occur during a transient increase in body temperature. Feeding is initiated by a dip in blood glucose concentration after sugar uptake by activated BAT.

Results: In 14 neonates (bottle‐fed on demand), food intake always took place during an increase in skin temperature (+0.19 ± 0.21 °C). Awakening occurred 18 ± 17 minutes after the minimum skin temperature level had been reached. When feeding time was imposed, feeding was not necessarily situated during an increase in skin temperature, and the sleep duration after food intake increased significantly (+43%). This could be considered as an adaptive response to the short‐term sleep deprivation and/or stress elicited by an imposed feeding rhythm.

Discussion: The validity of the model supports the use of on‐demand feeding in neonatal care units, in accordance with the infant's physiological body temperature oscillations.
Hip‐Hop to Health Jr. for Latino Preschool Children
Authors: Fitzgibbon Marian L. , Stolley Melinda R. , Schiffer Linda , Van Horn Linda , KauferChristoffel Katherine , Dyer Alan
Published: April 2008

Objective: Hip‐Hop to Health Jr. was a diet/physical activity intervention designed to reduce gains in BMI (kilograms per meter squared) in preschool minority children.

Research Methods and Procedures: Twelve predominantly Latino Head Start centers participated in a group‐randomized trial conducted between Fall 2001 and Winter 2003. Six centers were randomized to a culturally proficient 14‐week (three times weekly) diet/physical activity intervention. Parents participated by completing weekly homework assignments. The children in the other six centers received a general health intervention that did not address either diet or physical activity. The primary outcome was change in BMI, and secondary outcomes were changes in dietary intake and physical activity. Measures were collected at baseline, post‐intervention, and at Years 1 and 2 follow‐up.

Results: There were no significant differences between intervention and control schools in either primary or secondary outcomes at post‐intervention, Year 1, or Year 2 follow‐ups.

Discussion: When Hip‐Hop to Health Jr. was conducted in predominantly black Head Start centers, it was effective in reducing subsequent increases in BMI in preschool children. In contrast, when the program was conducted in Latino centers, it was not effective. Although the intervention did not prevent excessive weight gain in Latino children, it was very well received. Future interventions with this population may require further cultural tailoring and a more robust parent intervention.
Maternal Corticotropin‐Releasing Hormone Levels during Pregnancy and Offspring Adiposity
Authors: Gillman Matthew W. , Rich‐Edwards Janet W. , Huh Susanna , Majzoub Joseph A. , Oken Emily , Taveras Elsie M. , Rifas‐Shiman Sheryl L.
Published: April 2008

Objective: Animal models suggest that fetal exposure to glucocorticoids can program adiposity, especially central adiposity, later in life. We examined associations of maternal corticotropin‐releasing hormone (CRH) levels in the late 2nd trimester of pregnancy, a marker of fetal glucocorticoid exposure, with child adiposity at age 3 years.

Research Methods and Procedures: We analyzed data from 199 participants in Project Viva, a prospective cohort study of pregnant women and their children, At age 3 years, the main outcomes were age‐sex‐specific BMI z score and the sum of subscapular (SS) and triceps (TR) skinfold thicknesses to represent overall adiposity, and ratio of SS to TR (SS:TR) to represent central adiposity.

Results: Mean (standard deviation) maternal 2nd trimester log CRH was 4.94 (0.56) pg/mL. At age 3, mean (standard deviation) for BMI z score was 0.52 (1.02); for SS + TR, 16.51 (3.94) mm; and for SS:TR, 0.67 (0.17). Log CRH was mildly inversely correlated with birth weight (r = −0.08), chiefly because of its association with length of gestation (r = −0.21) rather than fetal growth (r = −0.004). After adjustment for sociodemographic factors, maternal smoking, BMI, and gestational weight gain, fetal growth, length of gestation, breastfeeding duration, and (for SS:TR only) child's 3‐year BMI, each increment of 1 unit of log CRH was associated with a reduction in BMI z score [−0.43; 95% confidence interval (CI), −0.73, −0.14; p = 0.004] and possible reduction in SS + TR (−1.10; 95% CI, −2.33, 0.14; p = 0.08). In contrast, log CRH was associated with higher SS:TR (0.07; 95% CI, 0.02, 0.13; p = 0.007).

Discussion: Fetal exposure to glucocorticoids, although associated with an overall decrease in body size, may cause an increase in central adiposity.
Body Composition and Fatness Patterns in Prader‐Willi Syndrome: Comparison with Simple Obesity
Authors: Theodoro Mariana F. , Talebizadeh Zohreh , Butler Merlin G.
Published: April 2008

Objective: To characterize the body composition of Prader‐Willi syndrome (PWS) subjects and compare with simple obesity.

Research Methods and Procedures: Seventy‐two individuals (27 PWS deletion, 21 PWS uniparental disomy, and 24 obese controls) 10 to 49 years old were studied with the use of DXA. Body composition measures were obtained, and regional fat and lean mass patterns were characterized. Significant differences were assessed with Student's t test and ANOVA adjusting for age, gender, and BMI.

Results: Significant differences between the PWS and obese groups were found for lean measures of the arms, legs, and trunk. Total lean mass was significantly lower in PWS than in obese subjects for arms, trunk, and especially legs. Furthermore, two body regions (legs and trunk) showed significant differences for fat and lean measures between PWS and obese males. However, significant differences between PWS and obese females for these measures were found only for the legs. No significant differences were identified between PWS deletion and uniparental disomy subjects.

Discussion: Our results demonstrate that PWS individuals do, in fact, have an unusual body composition and fatness patterns, characterized by reduced lean tissue and increased adiposity, with PWS males contributing most with fat patterns more similar to females.
Rise of Plasma Ghrelin With Weight Loss is Not Sustained During Weight Maintenance
Authors: Garcia Jose M. , Iyer Dinakar , Poston Walker S. C. , Marcelli Marco , Reeves Rebecca , Foreyt John , Balasubramanyam Ashok
Published: April 2008

Objective: Ghrelin is postulated to be an orexigenic signal that promotes weight regain after weight loss (WL). However, it is not known whether this putative effect of ghrelin is sustained after weight stabilization. The objective of this study was to investigate the relationship of plasma ghrelin concentrations to active WL and weight maintenance in obese subjects.

Research Methods and Procedures: This study was a randomized clinical trial, with a 12‐month follow‐up period. Obese Mexican‐American women matched for age and BMI were randomized to a 12‐month WL program (n = 25) or no intervention (controls, n = 23). Interventions included diet, exercise, and orlistat. Body weight and fasting ghrelin, leptin, insulin, and glucose concentrations were measured at baseline and 6 and 12 months.

Results: The WL group lost 8.5% of body weight after 6 months and maintained the new weight for the next 6 months. Ghrelin concentrations increased significantly at 6 months but returned to baseline at 12 months. Baseline ghrelin concentrations were directly related to the degree of WL achieved after 12 months. Controls experienced no change in BMI or ghrelin levels. There were no associations between plasma ghrelin and leptin or insulin concentrations.

Discussion: Consistent with previous results, ghrelin rises in response to WL, perhaps as a counterregulatory mechanism. However, the present results indicate that ghrelin concentrations return to baseline with sustained weight maintenance, suggesting that its effects are unlikely to regulate long‐term energy balance. Baseline ghrelin concentrations are related to the degree of WL that can be achieved by active weight reduction.
Iron Deficiency in Obese Postmenopausal Women
Authors: Lecube Albert , Carrera Alicia , Losada Eladio , Hernández Cristina , Simó Rafael , Mesa Jordi
Published: April 2008

Objective: This study evaluates whether the iron deficiency suggested in children and adolescents with overweight is also present with increasing age.

Research Methods and Procedures: We examined 50 consecutive postmenopausal nondiabetic white women with a BMI ≥30 kg/m2 and 50 non‐obese seemingly healthy women as a control group. In addition to the traditional indices of iron status, we measured the soluble transferrin receptor (sTfR) levels, a sensitive and highly quantitative indicator of early iron deficiency not influenced by the acute phase response.

Results: Obese women have higher serum sTfR levels than control subjects [1.38 (range, 0.89 to 2.39) vs. 1.16 mg/dL (range, 0.69 to 2.03 mg/dL); p < 0.001]. However, no difference in ferritin concentration was observed between the groups [70.50 (range, 18 to 219) vs. 69.50 ng/mL (range, 24 to 270 ng/mL); p = not significant]. A positive correlation between BMI and sTfR concentration was detected. On multiple regression analyses, BMI (positively) and ferritin (inversely) were independent predictors accounting for sTfR.

Discussion: These results suggest that a moderate degree of iron deficiency is also present among adult women with obesity. The determination of sTfR is useful in the evaluation of iron status in this condition. Further studies with a greater number of patients are required to investigate the relationship between tissue iron concentrations and obesity.
Transition from Overweight to Obesity Worsens Pregnancy Outcome in a BMI‐dependent Manner
Authors: Raatikainen Kaisa , Heiskanen Nonna , Heinonen Seppo
Published: April 2008

Objective: To assess pregnancy outcomes in different BMI groups.

Research Methods and Procedures: We analyzed 25, 601 singleton pregnancies from January 1989 to December 2001. Overweight women (prepregnancy BMI = 26 to 29 kg/m2) represented 13.2% (3388) of the cases, and 7.3% (1880) were obese (BMI ≥ 30 kg/m2). The data were obtained from self‐administered questionnaires at 20 weeks of pregnancy, complemented by nurse interviews and clinical records. Multiple logistic regression analysis was used to control for confounding factors.

Results: Overweight and obese women had more previous deliveries, pregnancy terminations, miscarriages, and stillbirths, to have more diabetes and hypertension, and to smoke more often than normal weight women. The pregnancies were more often complicated by preeclampsia or chorioamnionitis (p < 0.001). Pregnancy outcomes were impaired in overweight and obese pregnant women, with respective odds ratios (95% confidence index) as follows: low Apgar score at 5 minutes, 1.54 (1.20 to 1.98) and 1.64 (1.22 to 2.28); newborn admission to a neonatal unit, 1.20 (1.06 to 1.37) and 1.38 (1.17 to 1.61); cesarean delivery, 1.22 (1.10 to 1.35) and 1.68 (1.48 to 1.91); fetal death, 1.54 (0.88 to 2.68) and 2.35 (1.28 to 4.32); perinatal death, 1.54 (0.98 to 2.42) and 2.19 (1.33 to 3.62).

Discussion: Obesity, in particular during pregnancy, should be considered as an abnormal situation. An overweight condition increases obstetric risks in a BMI‐dependent manner. The risk of perinatal death more than doubles in the transition from an overweight to an obese condition. Modest weight loss could bring substantial advantages to obstetric outcome.
MedGem Hand‐Held Indirect Calorimeter Is Valid for Resting Energy Expenditure Measurement in Healthy Children
Authors: Fields David A. , Kearney Jay T. , Copeland Kenneth C.
Published: April 2008

Objective: To assess the validity of a new hand‐held indirect calorimeter [MedGem (MG)] in the determination of resting energy expenditure (REE; kilocalories per day) in children.

Research Methods and Procedures: One hundred male (n = 54) and female (n = 46) children (10.6 ± 3.2 years, 43.9 ± 19.0 kg, 146.1 ± 18.8 cm, 19.6 ± 4.9 kg/m2) participated. Children arrived at the University of Oklahoma body composition laboratory between 5:30 am and 6:15 am after an overnight fast. On arrival, subjects voided and remained quietly in the supine position for 15 minutes before testing. REE was measured by indirect calorimetry (in random order), with both the MG (sitting upright) and the criterion Delta Trac II (DT) (supine). Data are reported as the mean ± standard deviation.

Results: The mean MG REE (1452 ± 355 kcal/d) was significantly higher than DT REE (1349 ± 296 kcal/d, p < 0.001). Bland‐Altman analysis revealed a mean bias (MG − DT) of 104 kcal/d, with limits of agreement of −241 to +449 kcal/d. To examine the difference in subject positioning, an independent sample of 38 subjects performed the MG in its normal position (sitting) and holding the MG in a supine position. REE by the MG in the sitting position (1475 ± 350 kcal/d) was significantly (p < 0.05) higher than the MG in the supine position (1419 ± 286 kcal/d).

Discussion: The mean difference in REE between MG and DT was relatively small (103 kcal/d) but significant; however, a portion of this difference may have been related to differences in subject positioning. These preliminary data indicate that the MG shows promise as a valid tool in the assessment of REE in children.
The PPET Study: People and Pets Exercising Together
Authors: Kushner Robert F. , Blatner Dawn Jackson , Jewell Dennis E. , Rudloff Kimberly
Published: April 2008

Objective: Obesity is a significant public health problem that is affecting people and their pets. The human‐companion animal bond and the role of pets in providing social support provides a rationale framework for studying the effectiveness of a combined people and pets (PP) exercising together (PPET) weight loss program.

Research Methods and Procedures: Thirty‐six pairs of overweight or obese people with an obese pet (PP) and 56 overweight or obese people only (PO) participated in a 1‐year prospective controlled weight loss study. In a group format, people received dietary and physical activity counseling, and dogs were fed a calorie‐controlled prescription diet. Physical activity was recorded using the physical activity recall questionnaire.

Results: Completion rates at 1 year were 61% for the PP group and 58% for the PO group. Mean weight losses at 12 months using last observation carried forward were 4.7% (PP) and 5.2% (PO). Mean weight loss among the dogs was 15%. Time spent in physical activity increased in both groups to 3.9 (PP) and 3.5 (PO) h/wk. Two‐thirds of total physical activity in the PP group was spent with the dogs.

Discussion: The PPET study is the first program to demonstrate the effectiveness of a combined PP weight loss program. This fresh approach to the dual obesity epidemic builds on the human‐companion animal bond. Consideration of social support for weight loss of family members, friends, and coworkers should be extended to include pets.
Locomotor Strategies in Obese and Non‐obese Children
Authors: Nantel Julie , Brochu Martin , Prince François
Published: April 2008

Objective: The constant strain in obese children may increase the risks of articular problems in adulthood. In the short term, obesity in children could lead to modifications of the gait pattern. The purpose of this study was to compare biomechanical parameters between obese and non‐obese children during self‐paced walking.

Research Methods and Procedures: Gait analysis was performed on 10 non‐obese and 10 obese (body weight > 95th percentile) children between 8 and 13 years of age. Subjects were asked to walk at their own pace on a 10‐m walkway with two embedded AMTI force plates (Advanced Mechanical Technology, Watertown, MA) sampling at 960 Hz. Kinematics were captured with eight VICON optoelectronic cameras (Oxford Metrics Limited, Oxford, United Kingdom) recording at 60 Hz.

Results: Obese children modified their hip motor pattern by shifting from extensor to flexor moment earlier in the gait cycle. This led obese children to significantly decrease the mechanical work done by the hip extensors during weight acceptance and significantly increase the mechanical work done by the hip flexors compared with non‐obese children. The ratio of power‐absorption‐by‐hip‐flexors to power‐generation‐by‐hip‐flexors was also significantly increased in the obese group compared with non‐obese children. Finally, there was a significant decrease in the single support duration in the obese group compared with non‐obese.

Discussion: The kinetics analyzed showed that obese children could take advantage of a passive hip strategy to achieve forward progression during walking. However, considering that they are mechanically less efficient to transfer energy, walking at a natural cadence should be an appropriate exercise to reduce weight in obese children.
Weight Maintenance 2 Years after Participation in a Weight Loss Program Promoting Low‐Energy Density Foods
Authors: Greene Lori F. , Malpede Christie Z. , Henson C. Suzanne , Hubbert Kathy A. , Heimburger Douglas C. , Ard Jamy D.
Published: April 2008

Objective: Observational study designed to determine weight outcomes and associated dietary intake patterns for a sample of participants ≥1 year after completing the University of Alabama at Birmingham EatRight Weight Management Program.

Research Methods and Procedures: Seventy‐four former participants (64% women) completed follow‐up visits ≥1 year after participating in EatRight, which promotes low‐energy density, high‐complex carbohydrate foods. Weight maintenance was defined as gaining <5% of body weight since completion of the EatRight program and staying below their program entry weight. Those who gained ≥5% of their body weight since completion were classified as gainers.

Results: During EatRight, participants of the follow‐up study lost an average of 4.0 kg. After a mean follow‐up time of 2.2 years, the average weight change was +0.59 kg (mean BMI, 32.5 kg/m2). Seventy‐eight percent of participants gained <5% of their body weight; 46% had no weight regain or continued weight loss. Unadjusted mean intake for maintainers was 1608 kcal, whereas calorie intake for gainers was 1989 kcal. Despite eating slightly fewer calories (adjusted difference, 244; p = 0.058), maintainers ate a similar amount of food, resulting in a lower energy‐density pattern (p = 0.016) compared with those who regained ≥5% of body weight. Gainers also reported consuming larger portions of several food groups.

Discussion: Our results indicate that low‐energy‐density eating habits are associated with long‐term weight maintenance. Those who maintain weight after the EatRight program consume a low‐energy‐density dietary pattern and smaller portions of food groups potentially high in energy density than those who regain weight.
Central Obesity as a Risk Factor for Prostatic Hyperplasia
Authors: Lee Sangyeoup , Min Hong Gi , Choi Sang Han , Kim Yun Jin , Oh Sang Woo , Kim Young Joo , Park Yongsoon , Kim Sung Soo
Published: April 2008

Objective: Obesity‐related metabolic diseases may influence prostatic hyperplasia. This study examined the impact of obesity on prostate volume in men without overt obesity‐related metabolic diseases.

Research Methods and Procedures: We recruited 146 men over the age of 40 years who did not have overt obesity‐related diseases, such as diabetes, impaired fasting glucose, hypertension, or dyslipidemia. Transrectal ultrasonography was performed on all subjects. The subjects were divided into three groups according to their BMI: normal (18.5 to 22.9 kg/m2), overweight (23 to 24.9 kg/m2), and obese (≥25 kg/m2), and two groups according to their waist circumference: normal waist (≤90 cm) and central obesity (>90 cm). The classification of the subgroups was based on the Asia‐Pacific criteria of obesity. We compared the prostate volume among subgroups and assessed factors related to prostatic hyperplasia.

Results: Mean prostate volume was 18.8 ± 5.0, 21.8 ± 7.2, and 21.8 ± 5.6 mL in the normal, overweight, and obese groups, respectively, and was 20.0 ± 5.9 and 23.7 ± 5.3 mL in the normal waist and central obesity group, respectively. Prostate volume was significantly greater in the obese group than in the normal group (P = 0.03) and in the central obesity group compared with the normal waist group (P = 0.002). Prostate volume was positively correlated with BMI and waist circumference after adjustment for age. After adjusting for confounding factors, central obesity was an independent factor affecting prostatic hyperplasia, which was defined as a prostate volume >20 mL (odds ratio = 3.37, p = 0.037). Relative to men with both low BMI (18.5 to 22.9 kg/m2) and normal waist circumference, those with high BMI (≥25 kg/m2) and central obesity were at significantly increased risk of prostatic hyperplasia (odds ratio = 4.88, p = 0.008). However, those with high BMI (≥25 kg/m2) and normal waist circumference were not at significantly increased risk.

Discussion: Prostate volume was greater in the obese and central obesity groups than in the normal group after patients with overt obesity‐related metabolic diseases were excluded. Although both BMI and waist circumference were positively correlated with prostate volume, central obesity was the only independent factor affecting prostate hyperplasia. We suggest that central obesity is an important risk factor for prostatic hyperplasia.
Regulation of Secreted Protein Acidic and Rich in Cysteine during Adipose Conversion and Adipose Tissue Hyperplasia
Authors: Chavey Carine , Boucher Jérémie , Monthouël‐Kartmann Marie‐Noëlle , Sage E. Helene , Castan‐Laurell Isabelle , Valet Philippe , Tartare‐Deckert Sophie , Van Obberghen Emmanuel
Published: April 2008

Objective: To explore the regulation of secreted protein acidic and rich in cysteine (SPARC) expression and its role in adipose tissue.

Research Methods and Procedures: We studied the regulation of SPARC expression in transgenic mice expressing the human β3 and α2 adrenergic receptors on a murine β3 adrenergic receptor null background that became obese under a high‐fat diet mainly as a result of adipose tissue hyperplasia. Furthermore, we analyzed its expression in human adipose tissue and its regulation during adipocyte differentiation.

Results: SPARC protein in adipose tissue was increased in obese transgenic mice compared with control mice, indicating that SPARC expression was associated with adipose tissue hyperplasia. Both SPARC mRNA and protein were detected in human adipose tissue. Comparing adipocytes and vascular stroma, we found that SPARC expression was mainly associated with the adipocyte fraction. Consistent with this, SPARC transcript increased during differentiation of human primary preadipocytes. 3T3‐L1 preadipocytes showed an increase in SPARC expression in differentiated cells but with biphasic expression during the process. After induction in committed cells, SPARC mRNA and protein levels declined as differentiation began and returned to elevated levels in fully differentiated adipocytes.

Discussion: SPARC expression correlated with adipose tissue hyperplasia and adipogenesis. Therefore, SPARC seems to play a role in adipose tissue physiology as it is involved in growth and differentiation.
Validation and Calibration of an Accelerometer in Preschool Children
Authors: Pate Russell R. , Almeida Maria J. , McIver Kerry L. , Pfeiffer Karin A. , Dowda Marsha
Published: April 2008

Objective: Obesity rates in young children are increasing, and decreased physical activity is likely to be a major contributor to this trend. Studies of physical activity in young children are limited by the lack of valid and acceptable measures. The purpose of this study was to calibrate and validate the ActiGraph accelerometer for use with 3‐ to 5‐year‐old children.

Research Methods and Procedures: Thirty preschool children wore an ActiGraph accelerometer (ActiGraph, Fort Walton Beach, FL) and a Cosmed portable metabolic system (Cosmed, Rome, Italy) during a period of rest and while performing three structured physical activities in a laboratory setting. Expired respiratory gases were collected, and oxygen consumption was measured on a breath‐by‐breath basis. Accelerometer data were collected at 15‐second intervals. For cross‐validation, the same children wore the same instruments while participating in unstructured indoor and outdoor activities for 20 minutes each at their preschool.

Results: In calibrating the accelerometer, the correlation between V̇o2 (ml/kg per min) and counts was r = 0.82 across all activities. The only significant variable in the prediction equation was accelerometer counts (R2 = 0.90, standard error of the estimate = 4.70). In the cross‐validation, the intraclass correlation coefficient between measured and predicted V̇o2 was R = 0.57 and the Spearman correlation coefficient was R = 0.66 (p < 0.001). Cut‐off points for moderate‐ and vigorous‐intensity physical activity were identified at 420 counts/15 s (V̇o2 = 20 mL/kg per min) and 842 counts/15 s (V̇o2 = 30 mL/kg per min), respectively. When these cutpoints were applied to the cross‐validation data, percentage agreement, kappa, and modified kappa for moderate activity were 0.69, 0.36, and 0.38, respectively. For vigorous activity, the same measures were 0.81, 0.13, and 0.62.

Discussion: Accelerometer counts were highly correlated with V̇o2 in young children. Accelerometers can be appropriately used as a measure of physical activity in this population.