bluuebunny/crossref_metadata_2025 huggingface dataset:
Plasma Adiponectin Levels in High Risk African‐Americans with Normal Glucose Tolerance, Impaired Glucose Tolerance, and Type 2 Diabetes**
Authors: Osei Kwame , Gaillard Trudy , Schuster Dara
Published: April 2008

Objective: We studied plasma adiponectin, insulin sensitivity, and insulin secretion before and after oral glucose challenge in normal glucose tolerant, impaired glucose tolerant, and type 2 diabetic first degree relatives of African‐American patients with type 2 diabetes.

Research Methods and Procedures: We studied 19 subjects with normal glucose tolerance (NGT), 8 with impaired glucose tolerance (IGT), and 14 with type 2 diabetes. Serum glucose, insulin, C‐peptide, and plasma adiponectin levels were measured before and 2 hours after oral glucose tolerance test. Homeostasis model assessment‐insulin resistance index (HOMA‐IR) and HOMA‐β cell function were calculated in each subject using HOMA. We empirically defined insulin sensitivity as HOMA‐IR < 2.68 and insulin resistance as HOMA‐IR > 2.68.

Results: Subjects with IGT and type 2 diabetes were more insulin resistant (as assessed by HOMA‐IR) when compared with NGT subjects. Mean plasma fasting adiponectin levels were significantly lower in the type 2 diabetes group when compared with NGT and IGT groups. Plasma adiponectin levels were 2‐fold greater (11.09 ± 4.98 vs. 6.42 ± 3.3811 μg/mL) in insulin‐sensitive (HOMA‐IR, 1.74 ± 0.65) than in insulin‐resistant (HOMA‐IR, 5.12 ± 2.14) NGT subjects. Mean plasma adiponectin levels were significantly lower in the glucose tolerant, insulin‐resistant subjects than in the insulin sensitive NGT subjects and were comparable with those of the patients with newly diagnosed type 2 diabetes. We found significant inverse relationships of adiponectin with HOMA‐IR (r = −0.502, p = 0.046) and with HOMA‐β cell function (r = −0.498, p = 0.042) but not with the percentage body fat (r = −0.368, p = 0.063), serum glucose, BMI, age, and glycosylated hemoglobin A1C (%A1C).

Discussion: In summary, we found that plasma adiponectin levels were significantly lower in insulin‐resistant, non‐diabetic first degree relatives of African‐American patients with type 2 diabetes and in those with newly diagnosed type 2 diabetes. We conclude that a decreased plasma adiponectin and insulin resistance coexist in a genetically prone subset of first degree African‐American relatives before development of IGT and type 2 diabetes.
Trends in Obesity and Overweight‐Related Office Visits and Drug Prescriptions in Canada, 1998 to 2004
Authors: Padwal Raj S.
Published: April 2008

Objective: Obesity and overweight are affecting increasing numbers of Canadians and have received considerable amounts of medical, governmental, and media attention in recent years. This study sought to determine whether this rise in prevalence and awareness has resulted in an increased frequency of obesity and overweight‐related office visits or antiobesity drug prescriptions over the past 5 years.

Research Methods and Procedures: Data from IMS Health Canada were used to derive nationally representative estimates of trends in the annual number of obesity and overweight‐related office visits (1999 to 2003) and the quarterly prescription volume of antiobesity drugs (July 1998 to March 2003) in Canada.

Results: The number of obesity and overweight‐related office visits increased by 20% between 1999 and 2000 but then remained constant. The number of antiobesity drug prescriptions peaked in 2001 and has since declined, with parallel trends being observed for all individual agents. In contrast, the overall frequency of office visits and drug prescriptions in Canada (for any reason) progressively increased over the study period. Middle‐aged women were the most common type of patient to seek physician advice regarding obesity, and general practitioners were the most common type of physician visited.

Discussion: Increases in the prevalence and awareness of obesity have not resulted in major increases in office visits or drug prescriptions for this condition over the past 5 years. A number of patient, physician, and drug‐related factors may explain these results, which are likely a reflection primarily of the current lack of effective weight loss strategies for obese individuals.
Effects of Irbesartan on the Growth and Differentiation of Adipocytes in Obese Zucker Rats
Authors: Di Filippo Clara , Lampa Enrico , Tufariello Elisabetta , Petronella Pasquale , Freda Fulvio , Capuano Annalisa , D'Amico Michele
Published: April 2008

Objective: The aim of this study was to evaluate the effects of the selective angiotensin receptor 1 antagonist irbesartan on the growth and differentiation of the adipocytes in obese Zucker fa/fa rats.

Research Methods and Procedures: Obese Zucker fa/fa rats were treated by oral route for 3 weeks with irbesartan at doses of 3–10‐30 mg/kg per day. The adipocyte differentiation was evaluated by analyzing tissue samples of white (retroperitoneal) or brown (interscapular) adipose tissue for the presence of peroxisome proliferator activated receptor γ, leptin, and the activity of glycerol‐3‐phosphate dehydrogenase.

Results: This study showed that the treatment of obese Zucker fa/fa with irbesartan effectively reduced the differentiation of adipocytes within brown (interscapular) and white (retroperitoneal) adipose tissue. In fact, irbesartan significantly (p < 0.01) and dose‐dependently reduced the tissue levels of leptin, peroxisome proliferator activated receptor γ, and the activity of the enzyme glycerol‐3‐phoshate dehydrogenase accepted markers of adipocyte differentiation. None of the tested doses of irbesartan affected these markers in non‐obese rats.

Discussion: The antagonism of the angiotensin receptor 1 receptors with irbesartan reduces the adipogenic activity of angiotensin II in obese Zucker rats, with the endpoint being reduction of the growth and differentiation of the adipocytes within the adipose tissue.
(+)‐Z‐Bisdehydrodoisynolic Acid Ameliorates Obesity and the Metabolic Syndrome in Female ZDF Rats
Authors: Banz William J. , Davis Jeremy , Steinle Jena J. , Adler Stuart , Oitker Jennifer , Winters Todd A. , Higginbotham D. Allan , Hou Yuqing , Henry Nancy , Peterson Richard , Meyers Cal Y.
Published: April 2008

Objective: The putative selective estrogen receptor modulator (+)‐Z‐bisdehydrodoisynolic acid (Z‐BDDA) has been found to improve cardiovascular risk in rodents. The objective of this study was to investigate the effectiveness of (+)‐Z‐BDDA compared with the antidiabetic drug, rosiglitazone, in treating obesity and risk factors associated with the metabolic syndrome.

Research Methods and Procedures: Female Zucker Diabetic Fatty rats were randomly assigned to three treatment groups for 29 weeks: control (C), 1.8 mg (+)‐Z‐BDDA/kg diet [control diet + (+)‐Z‐BDDA (CB)], or 100 mg rosiglitazone/kg diet [control diet + rosiglitazone (CR)]. At sacrifice, physiological, biochemical, and molecular parameters were examined.

Results: CB animals gained less weight and exhibited a decrease in total body lipids (p < 0.05) as compared with C or CR rats. Body weight and total body lipids were the highest in CR rats (p < 0.05). Liver weights in CB and CR rats were lower (p < 0.05) than in C rats, whereas kidney weights were lower in CB (p < 0.05) than in C and CR animals. Fasting plasma glucose was lower (p < 0.05) in the CB and CR animals when compared with C animals. C rats exhibited the highest concentration of total plasma cholesterol, and CR‐treated rats exhibited the lowest concentration. Plasma triglycerides followed the same pattern as plasma cholesterol. Histomorphometry of heart vasculature revealed that CB and CR treatments produced a significant shift from small to large venules and arterioles compared with C (p < 0.05). Liver expression profiles of peroxisome proliferator‐activated receptor (PPAR) α, PPARγ, and PPAR‐regulated genes revealed encouraging CB‐induced effects.

Discussion: These results suggest that (+)‐Z‐BDDA may have applications in treating obesity and complications associated with the metabolic syndrome.
Weight Loss Expectations in Obese Patients and Treatment Attrition: An Observational Multicenter Study
Authors: Dalle Grave Riccardo , Calugi Simona , Molinari Enrico , Petroni Maria Letizia , Bondi Mario , Compare Angelo , Marchesini Giulio ,   QUOVADIS Study Group
Published: April 2008

Objective: To investigate the influence of weight loss expectations (expected 1‐year BMI loss, dream and maximum acceptable BMI) on attrition in obese patients seeking treatment.

Research Methods and Procedures: Obese subjects (1785; 1393 women; median age, 46 years; median BMI, 36.7 kg/m2) seeking treatment in 23 medical Italian centers were evaluated. Baseline diet and weight history, weight loss expectations, and primary motivation for seeking treatment (health or improving appearance) were systematically recorded. Psychiatric distress, binge eating, and body image dissatisfaction were tested at baseline by self‐administered questionnaires (Symptom Check List‐90, Binge Eating Scale, and Body Uneasiness Test). Attrition and BMI change at 12 months were prospectively recorded.

Results: At 12 months, 923 of 1785 patients (51.7%) had discontinued treatment. Compared with continuers, drop‐outs had a significantly lower age, a lower age at first dieting, lower dream BMI, a higher expected 1‐year BMI loss, and a higher weight phobia. At logistic regression analysis, the strongest predictors of attrition at 12 months were lower age and higher expected 1‐year BMI loss. The risk of drop‐out increased systematically for unit increase in expected BMI loss at 12 months (hazard ratio, 1.12; 95% confidence interval, 1.04 to 1.20; p = 0.0018). The risk was particularly elevated in the first 6 months.

Discussion: Baseline weight loss expectations are independent cognitive predictors of attrition in obese patients entering a weight‐losing program; the higher the expectations, the higher attrition at 12 months. Unrealistic weight goals should be tackled at the very beginning of treatment.
Major Depression Predicts an Increase in Long‐Term Body Weight Variability in Young Adults
Authors: Hasler Gregor , Lissek Shmuel , Ajdacic Vladeta , Milos Gabriella , Gamma Alex , Eich Dominique , Rössler Wulf , Angst Jules
Published: April 2008

Objective: To test the hypothesis that major depression predicts an increase in long‐term body weight variability (BWV).

Research Methods and Procedures: This was a prospective community‐based single‐age cohort study of young adults (N = 591) followed between the ages of 19 and 40. Following initial screening, information was derived from six subsequent semistructured diagnostic interviews conducted by mental health professionals. Major depression was diagnosed on the basis of DSM criteria. BWV was defined as the root mean square error of a regression line fitted to each individual's BMI values over time. Multiple regression analysis was used to test the association between major depression and BWV while controlling for potentially confounding variables including antidepressant treatment, eating disorder symptoms, and physical activity. We used random effects models to determine the temporal relationship between repeated measures of major depression and body weight change.

Results: A highly significant positive association between major depression and BWV was found, whereas major depression was not associated with BMI level or BMI trend. Depression severity showed a dose‐response‐type relationship with the magnitude of BWV. After controlling for potentially confounding variables including antidepressant use, eating disorder symptoms, smoking, and physical activity, major depression remained a significant predictor of BWV (β= 0.13, p < 0.001). Longitudinal analysis revealed a unidirectional association between major depression and a later increase in body weight change rate irrespective of antidepressant medication.

Discussion: Results from this study implicate depression as an important risk factor for increased BWV. Given increasing evidence for a link between major depression and both diabetes and cardiovascular disease, current results encourage further research on depression, BWV, and negative health outcomes.
Associations of Maternal Prenatal Smoking with Child Adiposity and Blood Pressure
Authors: Oken Emily , Huh Susanna Y. , Taveras Elsie M. , Rich‐Edwards Janet W. , Gillman Matthew W.
Published: April 2008

Objective: To examine the extent to which maternal prenatal smoking is associated with adiposity, central adiposity, and blood pressure in 3‐year‐old children.

Research Methods and Procedures: We studied 746 mother‐child pairs in Project Viva, a prospective cohort study, and categorized mothers as never, early pregnancy, or former smokers. Main outcome measures were overweight (BMI for age and sex > 85th percentile), BMI z‐score, sum of subscapular (SS) and triceps (TR) skinfolds, SS:TR skinfold ratio, and systolic blood pressure (SBP).

Results: One hundred sixty‐one (22%) mothers quit smoking before pregnancy, 71 (10%) smoked in early pregnancy, and 514 (69%) never smoked. At age 3 years, 204 (27%) children were overweight. On multivariable analysis, compared with children of never smokers, children of early pregnancy smokers had an elevated risk for overweight [odds ratio (OR), 2.2; 95% confidence interval (CI), 1.2, 3.9] and higher BMI z‐score (0.30 units; 95% CI, 0.05, 0.55), SS + TR (2.0 mm; 95% CI, 0.9, 3.0), and SBP (2.4 mm Hg; 95% CI, −0.1, 4.9). Children of former smokers were not more overweight (BMI z‐score, 0.02 units; 95% CI, −0.15, 0.19) but had higher SBP (1.5 mm Hg; 95% CI, −0.1, 3.2). We saw no relationship of smoking with central adiposity (SS:TR).

Discussion: Former and early pregnancy smokers had children with somewhat higher SBP, but only early pregnancy smokers had children who were more overweight. Mechanisms linking smoking with child adiposity and blood pressure may differ. A long‐term impact of maternal smoking on offspring cardiovascular risk provides further reason to reduce smoking in women.
Population‐based Study of Trends, Costs, and Complications of Weight Loss Surgeries from 1990 to 2002
Authors: Mehrotra Chetna , Serdula Mary , Naimi Timothy S. , Khan Laura Kettel , Miller Jacqueline , Dietz William
Published: April 2008

Objective: To describe the trends, costs, and complications associated with weight loss surgery (WLS).

Research Methods and Procedures: Wisconsin inpatient hospital discharge data from 1990 to 2003 were used for analysis. A WLS case was defined as anyone with a WLS‐related procedure code and a primary diagnosis of morbid obesity. Charges were inflation‐adjusted to 2001 constant dollars; complications were defined on the basis of readmission, extended length of stay, repeat surgical procedures, or death.

Results: The number of WLSs increased from 269 in 1990 to 1992 to 1884 in 2000 to 2002 (rate ratio = 4.6). Increases in WLSs were greatest among those 50 to 59 years of age (rate ratio = 6.4), women (rate ratio = 6.8), and blacks (rate ratio = 20.0). Between the two periods, inflation‐adjusted WLS charges increased 12‐fold, and the inflation‐adjusted charge per procedure doubled, despite a decreased length of stay. For 2000 to 2002, 23.3% of WLS patients had either an extended length of stay or readmission within 30 days, 7.4% required a repeat surgical procedure, and 0.7% died.

Discussion: In Wisconsin, the rate and costs of WLSs have increased dramatically, and the incidence of postoperative complications was high. The epidemic of obesity in the United States makes it imperative to better assess the cost‐effectiveness of WLS and to improve its safety.
Characteristics of Patients Undergoing Bariatric Surgery in Canada
Authors: Padwal Raj S.
Published: April 2008

Objective: The increasing prevalence of obesity has led to an increased use of bariatric surgery in the treatment of severely obese individuals. The characteristics of patients undergoing bariatric procedures outside of clinical studies and on a national level have not previously been reported.

Research Methods and Procedures: Acute‐care hospital discharge data from the Canadian Institute for Health Information were analyzed to determine the demographic and clinical features and in‐hospital mortality rates of individuals undergoing bariatric surgery in Canada. Data from individuals undergoing surgery in fiscal year 2002/2003 were compared with data from 1993/1994.

Results: Over 1100 bariatric surgeries were performed in Canada in 2002/2003, with the vast majority being performed in middle‐aged women. Ten percent of patients had hypertension or diabetes, and only 1% or fewer had dyslipidemia or cardiovascular or cerebrovascular disease. Compared with 1993/1994, patients undergoing surgery in 2002/2003 were older, more likely to have diabetes or hypertension, and had shorter hospital stays. In‐hospital mortality rates were <1% in both years.

Discussion: In the last decade, there has been a small increase in the average age and the number of patients with concomitant cardiovascular risk factors who are undergoing bariatric procedures in Canada. However, the vast majority of surgeries are being performed in middle‐aged women with little cardiovascular comorbidity, and this is likely contributing to very low in‐hospital death rates. Such individuals likely represent a highly selected sample of severely obese patients within Canada.
Peptide‐YY Levels after a Fat Load in Black and White Women
Authors: Davis Julianne , Hickner Robert C. , Tanenberg Robert J. , Barakat Hisham
Published: April 2008

Objective: To determine whether basal plasma peptide‐YY (PYY) levels in overweight, middle‐aged black women are different from those of white women of similar BMI and age and ascertain whether there is a difference between the two groups in plasma PYY levels in response to a liquid high fat load.

Research Methods and Procedures: Using a commercial radioimmunoassay kit, the concentration of PYY was measured at baseline and at 2, 4, 6, and 8 hours after ingesting a fatty liquid meal (86.5% of the calories from fat) in 12 black and 12 white women who were matched for age and BMI.

Results: PYY levels (picograms per milliliter) at baseline and at every other time‐point of the test meal were significantly lower in the black than in the white group. In addition, the change in PYY concentration from baseline was lower in the black than in the white group only at 8 hours after the meal.

Discussion: The lower baseline level and the blunted PYY response of the black women to the fat load indicated that this signal for appetite suppression was reduced, which, in turn, might contribute to the enhanced obesity of the black women.
Adolescent Sex Differences in Adiponectin Are Conditional on Pubertal Development and Adiposity
Authors: Woo Jessica G. , Dolan Lawrence M. , Daniels Stephen R. , Goodman Elizabeth , Martin Lisa J.
Published: April 2008

Objective: Adiponectin is an adipose tissue protein with important insulin‐sensitizing, anti‐inflammatory, and cardioprotective properties but is paradoxically lower in obese individuals. Sex differences in adiponectin have been reported in adults and adolescents but not in prepubertal children. In this study, we hypothesized that sex differences in adiponectin would develop during puberty and would be influenced by level of adiposity.

Research Methods and Procedures: Adiponectin levels were measured in 1196 white and African‐American adolescents. Insulin resistance was estimated using the homeostasis model (HOMA‐IR). Demographic, developmental, and metabolic variables, including interactions with adiposity measurements, were evaluated for independent relationships with adiponectin levels.

Results: Overall, adiponectin levels varied significantly by sex, race, adiposity, and puberty stage. Significant sex differences in adiponectin developed after the onset of puberty, particularly in lean adolescents. Adolescent boys had lower adiponectin levels in post‐puberty compared with pre‐puberty (p = 0.01) and had lower levels than girls in both puberty and post‐puberty (both p < 0.001), after adjusting for race, BMI z‐score, and natural logarithm‐(HOMA‐IR). Sex differences were also conditional on adiposity level, with significant sex differences among lean (p < 0.001) but not among non‐lean (p = 0.16) adolescents. Adiponectin levels in girls decreased more with increasing adiposity than in boys (p = 0.004), but only marginally so after standardizing for girls’ higher mean adiponectin level (p = 0.11).

Discussion: Sex differences in adiponectin are dependent on both puberty stage and adiposity in adolescents, such that by post‐puberty, non‐lean boys exhibit the lowest levels of adiponectin.
Water and Food Consumption Patterns of U.S. Adults from 1999 to 2001
Authors: Popkin Barry M. , Barclay Denis V. , Nielsen Samara J.
Published: April 2008

Objective: High water consumption has been proposed as an aid to weight control and as a means of reducing the energy density of the diet. This study examines the relationship between water consumption and other drinking and eating patterns.

Research Methods and Procedures: The National Health and Nutrition Examination Survey 1999 to 2001, with responses from 4755 individuals ≥18 years of age, provides the data for this cross‐sectional analysis. A cluster analysis was performed using z‐scores of specific food and beverage consumption to examine patterns. A multinomial logit analysis was used to examine sociodemographic characteristics of each dietary pattern and to examine the effects of water consumption on the likelihood of consuming a non–dairy caloric beverage. All results were weighted to be nationally representative and controlled for design effects.

Results: Within the sample, 87% consumed water, with an average daily consumption of 51.9 oz (1.53 liters) per consumer. Water consumers drank fewer soft/fruit drinks and consumed 194 fewer calories per day. Water consumers (potentially a self‐selected sample) consumed more fruits, vegetables, and low‐ and medium‐fat dairy products. Four distinct unhealthy dietary patterns were found that included little or no water consumption. Older and more educated persons used healthier food patterns. Mexican dietary patterns were much healthier than dietary patterns of blacks.

Discussion: Water consumption potentially is a dietary component to be promoted, but much more must be understood about its role in a healthy diet. Because high water consumption is linked with healthier eating patterns—patterns more likely to be followed by higher‐educated, older adults—the target of water promotion and healthy diet options should focus on younger and less educated adults.
Trends in Height and BMI of 6‐Year‐Old Children during the Nutrition Transition in Chile
Authors: Kain Juliana , Uauy Ricardo , Lera Lydia , Taibo Marcela , Albala Cecilia
Published: April 2008

Objective: We analyzed trends in height and BMI and their interaction in 6‐year‐old Chilean children over the last 15 years.

Research Methods and Procedures: We calculated height for age z‐score (HAZ), BMI z‐score, prevalence of obesity, underweight, and stunting from cross‐sectional national school‐based annual population surveys in 1987, 1990, 1993, 1996, 2000, and 2002. Using mixed model analysis, we determined the risk of obesity according to height over time as odds ratios (ORs) and 95% confidence interval and the potential influence of height and year of study on BMI z‐score.

Results: Over the study period, height increased by 2.8 cm in boys and 2.6 cm in girls, whereas stunting declined from 5% to 2% in both. Tallness increased by ∼2%, BMI z‐score increased from +0.3 to +0.65 in boys and to +0.62 in girls, and HAZ increased from −0.47 in boys and −0.45 in girls to 0 in 2002. Underweight declined from 4% to 3%, whereas obesity rose from 5% to ∼14%. The probability of obesity among tall children was significantly greater than that for normal height children (OR, 2.3 to 3.5). The lowest obesity risk was observed between −2 and −1 HAZ. The OR for obesity in the stunted relative to normal height children was variable, ranging from 1.23 to 0.65, whereas it was significant and consistently positive (1.1 to 1.7) for boys and girls when it was compared with the lowest obesity risk according to height.

Discussion: Tallness is significantly associated with increased obesity risk in children, while stunting is also associated, but to a lesser degree.
Gastric Bypass as Treatment for Obesity: Trends, Characteristics, and Complications
Authors: Shinogle Judith A. , Owings Maria F. , Kozak Lola Jean
Published: April 2008

Objective: This paper describes national trends in gastric bypass procedures from 1998 through 2003 and explores the demographic and health profile of those who receive this procedure. Short‐term outcomes such as length of stay and in‐hospital complication rates are also examined.

Research Methods and Procedures: Data on obese hospital inpatients who had gastric bypass were obtained from the 1998 to 2003 National Hospital Discharge Survey. Gastric bypass was reported for an estimated 288,000 discharges during the 6‐year study period. Trends within the 6‐year period were tested using weighted regression. Characteristics of gastric bypass patients were compared with those of other inpatients using a χ2 test of independence and the two‐sided t test.

Results: The estimated number of hospital discharges with gastric bypass increased significantly, from 14,000 in 1998 to 108,000 in 2003. During this period, the average length of stay declined by 56% from 7.2 to 3.2 days. Gastric bypass patients were primarily women (84%), 25 to 54 years of age (82%), and privately insured (76%). A 1 in 10 complication rate was found for discharges with gastric bypass.

Discussion: Gastric bypass procedures in the United States have increased rapidly since 1998, whereas the average hospital stay has decreased. The decreasing length of stay needs to be evaluated in conjunction with potential complication rates and the permanent change in anatomy and lifestyle that must accompany this procedure. Monitoring trends in use of this procedure is important, especially if reimbursement policies change and the epidemic of obesity continues.
Obesity among People with and without Mental Retardation across Adulthood
Authors: Moran Robert , Drane Wanzer , McDermott Suzanne , Dasari Srikanth , Scurry Joy B. , Platt Tan
Published: April 2008

Objective: This study was designed to explore obesity during adulthood and the likelihood of moving out of obesity among 1809 adults without disability and 680 adults with mental retardation who received care at the same primary care practices during the period of 1990 to 2003.

Research Method and Procedures: A retrospective observational design using medical records first identified patients with mental retardation (MR) and age‐matched controls without disabilities. Data on BMI collected during each primary care visit allowed exploration of obesity at three levels. Moving out of obesity was defined as having a BMI <25 kg/m2. We also abstracted data on age, sex, race, and other medical conditions.

Results: For adults 20 to 29 years of age, 33.1% of patients without disability and 21% of patients with MR had a BMI >30 kg/m2. Between the ages of 50 and 59 years, 40.5% of the patients without disability and 35.2% of the patients with MR had a BMI >30 kg/m2. Patients with mild MR had similar prevalence rates of obesity and patients with severe MR had significantly lower prevalence of obesity compared with the patients without disability through 50 years of age. Throughout the period from 20 to 60 years of age, between 15% and 40% of individuals with and without MR, who were previously obese, were not currently obese.

Discussion: Throughout the adult years, an increasing proportion of individuals with and without MR are obese. However, obesity is not a chronic state; many people transition back to a normal body weight.
Gastric Motor and Sensory Functions in Obesity
Authors: Park Moo‐In , Camilleri Michael
Published: April 2008

In the vast majority of affected individuals, obesity involves overconsumption of food relative to calorie requirements. The sensory function of the stomach may play a key role in the cessation of food ingestion. This sensation of the stomach is, in part, determined by its motor functions, such as tone and compliance and the rate of emptying. However, studies of gastric emptying in normal‐weight and obese persons have shown inconsistent results. Gastric capacity was larger in obese persons when tested with an intragastric latex balloon filled with water. In contrast, other studies using the barostat or imaging (single‐photon emission computed tomography) techniques reported no differences in gastric volume or compliance between obese and lean subjects. On the other hand, increased body mass and fasting gastric volume are independently associated with delayed satiation under standard laboratory conditions of food ingestion. These data suggest that changes in gastric motor and sensory functions in obesity may present useful targets to prevent and treat obesity. Further well‐controlled, validated studies are needed to clarify the potential role of altering the stomach's function as a means of controlling food intake in obesity.
Profile of Overweight and Obese People in a Mediterranean Region
Authors: Tur Josep A. , Serra‐Majem Lluís , Romaguera Dora , Pons Antoni
Published: April 2008

Objective: To assess the prevalence of excess weight (obesity and overweight) and the related environmental risk factors in a Mediterranean population. Self‐perception of body weight, attitudes toward weight‐control behaviors, and the associated factors were also examined.

Research Methods and Procedures: A cross‐sectional nutritional survey was carried out in the Balearic Islands between 1999 and 2000. A random sample (n = 1200) of the adult population (20 to 60 years old) was interviewed. Dietary questionnaires and a global questionnaire incorporating questions related to sociodemographic and lifestyle variables were utilized. Anthropometric measurements were also obtained.

Results: Nearly one‐half of the population of the Balearic Islands is above the normal weight range (BMI > 25). The predictors of overweight and obesity in the Balearic Islands are to be over 40 years old, to be married, to form part of the lowest educational levels, and to have a sedentary lifestyle. A large percentage of excess‐weight individuals tend to underestimate their BMI, are not concerned about their weight status, tend to snack more often, and have never dieted.

Discussion: Although the likely causes of the rise in obesity prevalence are difficult to elucidate from this study, we have identified the profile of individuals with excess weight in the Balearic Islands as well as their attitudes toward their body image.
Changes in Fat Mass Influence SREBP‐1c and UCP‐2 Gene Expression in Formerly Obese Subjects
Authors: Gniuli Donatella , Rosa Giuseppina , Manco Melania , Scarfone Antonino , Vega Nathalie , Greco Aldo V. , Castagneto Marco , Vidal Hubert , Mingrone Geltrude
Published: April 2008

Objective: To investigate the effect of fat mass (FM) reduction on adipose tissue gene expression in terms of lipid synthesis [sterol regulatory binding protein 1c (SREBP‐1c)] and lipid oxidation [uncoupling protein 2 (UCP‐2)] 2 years after lipid malabsorption and to assess the influence of lipid malabsorption on fat‐free mass (FFM) maintenance evaluating the expression of genes related to glycolysis [hexokinase (HKII)] and glucose storage [glycogen synthase (GS)].

Research Method and Procedures: SREBP‐1c, UCP‐2, HKII, and GS mRNA expression were studied by reverse transcriptase—competitive polymerase chain reaction in 10 massively obese subjects before and 2 years after bilio‐pancreatic diversion (BPD). Body composition was assessed by isotopic dilution method and insulin sensitivity by euglycemic‐hyperinsulinemic clamp.

Results: FM decrease was ∼60%, whereas FFM remained at normal physiological levels. In adipose tissue, SREBP‐1c mRNA reduction (−39%, p < 0.005) was related only to FM changes after BPD, and UCP‐2 decrease (−37%, p < 0.05) was dependent on free fatty acid (FFA) changes. No significant variations were observed in HKII and GS gene expression in skeletal muscle.

Discussion: Lipid malabsorption induced by BPD altered the expression of genes involved in glucose and lipid metabolism, with different consequences on FM and FFM. The degree of FM loss seems to interfere with SREBP‐1c gene suppression to preserve an adequate amount of fat storage, in accordance with the thrifty genotype hypothesis. The reduction of FFAs induced by BPD acts in inhibiting FFA transportation to the mitochondria (UCP‐2), contributing to the decreased lipid oxidation inside the adipose tissue.
Insulin and Endothelin in the Acute Regulation of Adiponectin in Vivo in Humans
Authors: Brame Lori A. , Considine Robert V. , Yamauchi Mikako , Baron Alain D. , Mather Kieren J.
Published: April 2008

Objective: In vitro, insulin and endothelin (ET) both modulate adiponectin secretion from adipocyte cell lines. The current studies were performed to assess whether endogenous ET contributes to the acute action of insulin infusions on adiponectin levels in vivo in humans.

Research Methods and Procedures: We studied 17 lean and 20 obese subjects (BMI 21.8 ± 2.2 and 34.0 ± 5.0 kg/m2, respectively). Hyperinsulinemic euglycemic clamp studies were performed using insulin infusion rates of 10, 30, or 300 mU/m2 per minute alone or with concurrent infusion of BQ123, an antagonist of type A ET receptors. Circulating adiponectin levels were assessed at baseline and after achievement of steady‐state glucose with the insulin infusion.

Results: Adiponectin levels were lower in obese than lean subjects (6.76 ± 3.66 vs. 8.37 ± 2.79 μg/mL, p = 0.0148 adjusted for differences across gender). Insulin infusions suppressed adiponectin by a mean of 7.8% (p < 0.0001). In a subset of 13 lean and 14 obese subjects for whom data with and without BQ123 were available, there was no evident effect of BQ123 to modulate clamp‐associated suppression of adiponectin (p = 0.16). Surprisingly, there was no evident relationship between steady‐state insulin concentrations and adiponectin suppression (r = 0.14, p = 0.30), and again no effect of BQ123 to modify this relationship was seen.

Discussion: Despite baseline differences in adiponectin levels, we observed equal suppression of adiponectin with insulin infusions in lean and obese subjects. ET receptor antagonism with BQ123 did not modulate this effect, suggesting that endogenous ET does not have a role in modifying the acute effects of insulin on adiponectin production and/or disposition.
Alleles on Rat Chromosome 4 (D4Got41‐Fabp1/Tacr1) Regulate Subphenotypes of Obesity
Authors: Klöting Nora , Wilke Barbara , Klöting Ingrid
Published: April 2008

Objective: The use of inbred animal models is an essential component of the genetic dissection of complex diseases. Because quantitative trait loci for serum triglycerides, total cholesterol, and body weight were mapped on chromosome 4 in a cross of BioBreeding/OttawaKarlsburg (BB/OK) and spontaneously hypertensive (SHR) rats, we established a congenic BB.SHR rat strain by introgressing a SHR segment of chromosome 4 (D4Got41‐Tacr1) into a BB/OK background. The phenotype of these BB.SHR rats (BB.4S) confirmed the quantitative trait loci. To discover whether the phenotype of BB.4S can only be attributed to the SHR segment per se, we established an additional congenic BB.WOKW strain by introgressing a similar segment of chromosome 4 (D4Got41‐Fabp1) of the Wistar Ottawa Karlsburg RT1u rat into a BB/OK background, termed briefly BB.4W.

Research Methods and Procedures: Male normoglycemic BB/OK (20), BB.4S (20), and BB.4W (16) rats were longitudinally studied for body weight, serum triglycerides, total and high‐density lipoprotein‐cholesterol, and glucose tolerance. At the end of the observation period (32 weeks), serum insulin, leptin, and adiposity index (AI) were determined.

Results and Discussion: Congenic BB.4S and BB.4W were significantly heavier, and AI, serum triglycerides, and total cholesterol values were significantly elevated in BB.4S and BB.4W compared with BB/OK but more pronounced in BB.4S. The highest serum insulin was found in BB.4W and highest leptin in BB.4S. Because the body weight gain and AI were comparable between BB.4S and BB.4W, the obviously higher insulin levels in BB.4W and higher leptin values in BB.4S suggest that the two congenics most probably define two subphenotypes of obesity and provide the unique opportunity to study their genetics.
Evaluation of Reference Genes for Studies of Gene Expression in Human Adipose Tissue
Authors: Gabrielsson Britt G. , Olofsson Louise E. , Sjögren Anders , Jernås Margareta , Elander Anna , Lönn Malin , Rudemo Mats , Carlsson Lena M. S.
Published: April 2008

Objective: The aim of this study was to evaluate reference genes for expression studies of human adipose tissue.

Research Methods and Procedures: Using 52 human adipose tissue expression profiles (HU95), 10 putative reference genes with the lowest variation in expression levels were selected for further studies. Expression stability of these 10 novel and 5 previously established reference genes was evaluated by real‐time reverse transcriptase‐polymerase chain reaction analysis. For this purpose, 44 adipose tissue biopsies from 27 subjects were chosen to include a wide range of parameters such as sex, age, BMI, depot origin, biopsy procedure, and effects of nutrition.

Results: LRP10 was identified as the gene with the least variation in expression levels. The frequently used reference genes RPLP0, 18S rRNA, PPIA, ACTB, and GAPD were ranked as 4, 6, 7, 8, and 10, respectively.

Discussion: Our results suggest that LRP10 is a better choice as reference for expression studies of human adipose tissue compared with the most frequently used reference genes.
Down‐regulation of Pyruvate Dehydrogenase Phosphatase in Obese Subjects is a Defect that Signals Insulin Resistance
Authors: Piccinini Marco , Mostert Michael , Alberto Gianfrancesco , Ramondetti Cristina , Novi Rosa F. , Dalmasso Paola , Rinaudo Maria T.
Published: April 2008

Objective: The objective of this study was to determine whether down‐regulation of pyruvate dehydrogenase phosphatase (PDP) is responsible for poorly active pyruvate dehydrogenase (PDH) in circulating lymphocytes (CLs) of obese subjects (ObS), and if so, whether it improves when their plasma insulin rises.

Research Methods and Procedures: PDH activity was compared in lysed CLs of 10 euglycemic ObS and 10 sex‐ and age‐matched controls before and during plasma insulin enhancement in an oral glucose tolerance test. It was evaluated without (PDHa) or with Mg/Ca or Mg at various concentrations to assess PDP1 or PDP2 activities or with Mg/Ca and exogenous PDP to determine total PDH activity (PDHt), which is an indirect measure of the amount of PDH. The insulin sensitivity index was calculated, and PDP1 and PDP2 mRNA was sought in the CLs.

Results: At T0 in ObS, PDHt was normal, whereas PDHa and PDP1 activity was below normal at all Mg/Ca concentrations. PDP2 activity was undetectable in both groups. PDP1 and PDP2 mRNA was identified, and insulin sensitivity index and PDHa were directly correlated. During the oral glucose tolerance test, plasma insulin rose considerably more in ObS than in controls; PDHa and PDP1 activity also increased but remained significantly below normal, and PDHt was unvaried in both groups.

Discussion: PDP1 is down‐regulated in CLs of ObS because it is poorly sensitive to Mg/Ca; this defect is attenuated when plasma insulin is greatly enhanced.
Prenatal Exposure to Nicotine Causes Postnatal Obesity and Altered Perivascular Adipose Tissue Function
Authors: Gao Yu‐Jing , Holloway Alison C. , Zeng Zhao‐Hua , Lim Gareth E. , Petrik James J. , Foster Warren G. , Lee Robert M.K.W.
Published: April 2008

Objective: Recent epidemiological studies have shown that there is an increased risk of obesity and hypertension in children born to women who smoked during pregnancy. The aim of this study was to examine the effect of fetal and neonatal exposure to nicotine, the major addictive component of cigarette smoke, on postnatal adiposity and blood vessel function.

Research Methods and Procedures: Female Wistar rats were given nicotine or saline (vehicle) during pregnancy and lactation. Postnatal growth was determined in the male offspring from weaning until 26 weeks of age. At 26 weeks of age, fat pad weight and the function of the perivascular adipose tissue (PVAT) in the thoracic aorta and mesenteric arteries were examined.

Results: Exposure to nicotine resulted in increased postnatal body weight and fat pad weight and an increased amount of PVAT in the offspring. Contraction of the aorta induced by phenylephrine was significantly attenuated in the presence of PVAT, whereas this effect was not observed in the aortic rings from the offspring of nicotine‐exposed dams. Phenylephrine‐induced contraction without PVAT was not different between saline‐ and nicotine‐exposed rats. Transfer of solution incubated with PVAT‐intact aorta to PVAT‐free aorta induced a marked relaxation response in the rats from saline‐exposed dams, but this relaxation response was significantly impaired in the rats from nicotine‐exposed dams.

Discussion: Our results showed that prenatal nicotine exposure increased adiposity and caused an alteration in the modulatory function of PVAT on vascular relaxation response, thus providing insight into the mechanisms underlying the increased prevalence of obesity and hypertension in children exposed to cigarette smoke in utero.
Interactive Multimedia for Promoting Physical Activity (IMPACT) in Children
Authors: Goran Michael I. , Reynolds Kim
Published: April 2008

Objective: To develop and examine the efficacy of a computer‐based interactive multimedia curriculum for promoting physical activity in fourth grade children.

Research Methods and Procedures: The participants were 209 fourth grade children (mean age of 9.5 ± 0.4 years) from four schools. Two schools received an 8‐week multimedia intervention delivered by interactive CD‐ROM, supplemented by four classroom and four homework assignments. Two control schools received educational CD‐ROMS not related to health outcomes. Measures conducted before and after intervention included height, weight, percentage body fat (bioimpedance analysis), physical activity (5‐day accelerometry), and psychosocial aspects of physical activity by questionnaire. All outcomes were examined using general linear models.

Results: There was a significant treatment effect for obesity reduction in girls but not in boys. There were no significant treatment effects on total physical activity by accelerometry (total counts per minute), but there was an overall treatment effect on reducing percent of time in moderate‐intensity activity (16.5% to 15% of the time) and significant sex‐by‐ treatment interactions for light‐intensity activities (reduction in boys from 78% to 75% of the time and an increase in girls from 78% to 81% of the time). There were marginal/significant treatment effects for improvements in behavioral outcomes, including self‐efficacy (p = 0.06), social norms (p = 0.07), and outcome expectancies (p = 0.049).

Discussion: The interactive multimedia curriculum favored an improvement in obesity indices in girls and was associated with subtle changes in physical activity in girls and general improvement in psychosocial outcomes related to physical activity.
Obesity‐related Comorbidities in Obese African Americans in an Outpatient Weight Loss Program
Authors: Hope Aluko A. , Kumanyika Shiriki K. , Whitt Melicia C. , Shults Justine
Published: April 2008

Objective: To identify, among obese African‐American enrollees in an outpatient weight loss program, differences between those with and without obesity‐related comorbidities (ORCMs).

Research Methods and Procedures: Data were from 237 obese African Americans (BMI, 30 to 50 kg/m2; 90% women) who enrolled in a 10‐week lifestyle weight loss program. Analyses compared subgroups defined by ORCM status (from medical history) on baseline characteristics, program attendance, and postprogram weight change.

Results: Most participants (76%) had one or more ORCMs. Those with versus without ORCMs, respectively, were older (mean age, 45.6 vs. 37.1 years;p< 0.001), were less educated (59.2% vs. 76.6% with >12 years;p= 0.031), were more likely to perceive a physical limitation affecting activity (22.2% vs. 1.8%;p< 0.001), and had higher waist circumference (mean, 113.7 vs. 106.9 cm;p< 0.001) but not BMI (38.3 vs. 37.0 kg/m2;p= 0.095). Logistic regression analyses confirmed the independence of these associations. Having ORCMs was not associated with class attendance or return for data collection after the 10‐week program. Postprogram weight change (n= 134) was unrelated to ORCMs, but better weight loss was seen among those without perceived physical limitations (1.9 vs. 0.4 kg in those without versus with limitations;p= 0.069).

Conclusion: Data from this clinical sample of obese African Americans suggest that waist circumference is relevant to ORCM status at BMI levels up to 50 kg/m2. Clear indications for tailoring of treatment based on ORCM status were not identified, although the possible influence of ORCM‐related activity limitations warrants further study.
Protein Tyrosine Phosphatase 1B Variant Associated with Fat Distribution and Insulin Metabolism
Authors: Ukkola Olavi , Rankinen Tuomo , Lakka Timo , Leon Arthur S. , Skinner James S. , Wilmore Jack H. , Rao D.C. , Kesäniemi Y.A. , Bouchard Claude
Published: April 2008

Protein tyrosine phosphatase 1B (PTPN1) affects the regulation of insulin signaling and energy metabolism. We studied whether polymorphisms in the PTPN1 gene impact body fat distribution in the HERITAGE Family Study cohort in 502 white and 276 black subjects. Insulin sensitivity index, glucose disappearance index, acute insulin response to glucose (AIRglucose), and the disposition index (DI) were obtained from the frequently sampled intravenous glucose tolerance test. White subjects with the G82G at the PTPN1 IVS6+G82A polymorphism had higher body fat levels (p = 0.031) and sum of eight skinfolds (p = 0.003) and highest subcutaneous fat on the limbs (p = 0.002). G82A subjects had the lowest AIRglucose (p = 0.005) and disposition index (p = 0.040). Interaction effects between PTPN1 and leptin receptor gene variants influenced insulin sensitivity index and AIRglucose (p from 0.006 to 0.010). The variant PTPN1 Pro387Leu was associated with lower fasting insulin level (p = 0.035) and glucose disappearance index (p = 0.038). In summary, PTPN1 IVS6+G82G homozygotes showed higher levels of all measures of adiposity. G82 allele heterozygotes are potentially at higher risk for type 2 diabetes. Gene‐gene interactions between the PTPN1 and leptin receptor genes contributed to the phenotypic variability of insulin sensitivity. The PTPN1 Pro387Leu variant was associated with lower glucose tolerance.