Are religiosity and spirituality associated with obesity among African Americans in the Southeastern United States (the Jackson Heart Study)?

There are several lines of evidence that suggest religiosity and spirituality are protective factors for both physical and mental health, but the association with obesity is less clear. This study examined the associations between dimensions of religiosity and spirituality (religious attendance, daily spirituality, and private prayer), health behaviors and weight among African Americans in central Mississippi. Jackson Heart Study participants with complete data on religious attendance, private prayer, daily spirituality, caloric intake, physical activity, depression, and social support (n = 2,378) were included. Height, weight, and waist circumference were measured. We observed no significant association between religiosity, spirituality, and weight. The relationship between religiosity/spirituality and obesity was not moderated by demographic variables, psychosocial variables, or health behaviors. However, greater religiosity and spirituality were related to lower energy intake, less alcohol use, and less likelihood of lifetime smoking. Although religious participation and spirituality were not cross-sectionally related to weight among African Americans, religiosity and spirituality might promote certain health behaviors. The association between religion and spirituality and weight gain deserves further investigation in studies with a longitudinal study design.

Calculation of expected body weight in adolescents with eating disorders

OBJECTIVE

To examine the agreement between three methods to calculate expected body weight (EBW) for adolescents with eating disorders: (1) BMI percentile, (2) McLaren, and (3) Moore methods.

METHODS

The authors conducted a cross-sectional analysis of baseline information from adolescents seeking treatment of disordered eating at The University of Chicago. Adolescents (N = 373) aged 12 to 18 years (mean = 15.84, SD = 1.72), with anorexia nervosa (n = 130), bulimia nervosa (n = 59), or eating disorder not otherwise specified (n = 184). Concurrence between the BMI percentile, McLaren, and Moore methods was assessed for agreement above or below arbitrary cut points used in relation to hospitalization (75%), diagnosis (85%), and healthy weight (100%). Patterns of absolute discrepancies were examined by height, age, gender, and menstrual status. Limitations to some of these methods allowed comparison between all 3 methods in only 204 participants.

RESULTS

Moderate agreement was seen between the 3 methods (κ values, 0.48-0.74), with pairwise total classification accuracy at each cut point ranging from 84% to 98%. The most discrepant calculations were observed among the tallest (>75th percentile) and shortest (<20th percentile) cases and older ages (>16 years). Many of the most discrepant cases fell above and below 85% EBW when comparing the BMI percentile and Moore methods, indicating disagreement on possible diagnosis of anorexia nervosa.

CONCLUSIONS

These methods largely agree on percent EBW in terms of clinically significant cut points. However, the McLaren and Moore methods present with limitations, and a commonly agreed-upon method for EBW calculation such as the BMI percentile method is recommended for clinical and research purposes.

Development of gender- and age group-specific equations for estimating body weight from anthropometric measurement in Thai adults

BACKGROUND

Many medical procedures routinely use body weight as a parameter for calculation. However, these measurements are not always available. In addition, the commonly used visual estimation has had high error rates. Therefore, the aim of this study was to develop a predictive equation for body weight using body circumferences.

METHODS

A prospective study was performed in healthy volunteers. Body weight, height, and eight circumferential level parameters including neck, arm, chest, waist, umbilical level, hip, thigh, and calf were recorded. Linear regression equations were developed in a modeling sample group divided by sex and age (younger <60 years and older ≥60 years). Original regression equations were modified to simple equations by coefficients and intercepts adjustment. These equations were tested in an independent validation sample.

RESULTS

A total of 2000 volunteers were included in this study. These were randomly separated into two groups (1000 in each modeling and validation group). Equations using height and one covariate circumference were developed. After the covariate selection processes, covariate circumference of chest, waist, umbilical level, and hip were selected for single covariate equations (Sco). To reduce the body somatotype difference, the combination covariate circumferences were created by summation between the chest and one torso circumference of waist, umbilical level, or hip and used in the equation development as a combination covariate equation (Cco). Of these equations, Cco had significantly higher 10% threshold error tolerance compared with Sco (mean percentage error tolerance of Cco versus Sco [95% confidence interval; 95% CI]: 76.9 [74.2-79.6] versus 70.3 [68.4-72.3]; P < 0.01, respectively). Although simple covariate equations had more evidence errors than the original covariate equations, there was comparable error tolerance between the types of equations (original versus simple: 74.5 [71.9-77.1] versus 71.7 [69.2-74.3]; P = 0.12, respectively). The chest containing covariate (C) equation had the most appropriate performance for Sco equations (chest versus nonchest: 73.4 [69.7-77.1] versus 69.3 [67.0-71.6]; P = 0.03, respectively). For Cco equations, although there were no differences between covariates using summation of chest and hip (C+Hp) and other Cco but C+Hp had a slightly higher performance validity (C+Hp versus other Cco [95% CI]: 77.8 [73.2-82.3] versus 76.5 [72.7-80.2]; P = 0.65, respectively).

CONCLUSION

Body weight can be predicted by height and circumferential covariate equations. Cco had more Sco error tolerance. Original and simple equations had comparable validity. Chest- and C+Hp-containing covariate equations had more precision within the Sco and Cco equation types, respectively.

Correction of long-lasting negative effects of neonatal isolation in white rats using semax

Adverse experience during the early postnatal period induces negative alterations in physiological and neurobiological functions, resulting in long-term disorder in animal behavior. The aim of the present work was to study the long-lasting effects of chronic neonatal stress in white rats and to estimate the possibility of their correction using Semax, an analogue of ACTH fragment (4-10). Early neonatal isolation was used as a model of early-life stress. Rat pups were separated from their mothers and littermates for 5 h daily during postnatal days 1-14. The pups of the control group were left undisturbed with the dams. Half of the rats subjected to neonatal isolation received an intranasal injection of Semax at a dose of 50 µg/kg daily, from postnatal day 15 until day 28. The other animals received intranasal vehicle injections daily at the same time points. It was shown that neonatal isolation leads to a delay in physical development, metabolic disturbances, and a decrease in the corticosterone stress response in white rats. These changes were observed during the first two months of life. Semax administration weakened the influence of neonatal isolation on the animals, body weight , reduced metabolic dysfunction, and led to an increase in stress-induced corticosterone release to the control values. So the chronic intranasal administration of Semax after termination of the neonatal isolation procedure diminishes the negative effects of neonatal stress.

Leptin resistance does not induce hyperphagia in the rat

Leptin has been thought to work as a mediator for body weight control by inhibiting food intake. Leptin, however, cannot prevent obesity induced by a high-fat diet (HFD) probably because of leptin resistance. We investigated daily feeding and weight gain when ordinary chow (OC) was changed to a HFD in male rats. Food intake, by weight, significantly increased the next day, but gradually decreased until at 20 days the HFD intake contained the same calories as consumed by the OC-fed control rats. The reduction in food intake occurred only during the night without change of preference for the HFD, even after leptin resistance had developed. Nonetheless, the HFD-fed rats gained more weight than the controls. From the present experiment, it is concluded that leptin resistance does not induce hyperphagia, and suggested that body weight is not regulated to be constant.

Race, ethnicity, and the relevance of obesity for social integration

OBJECTIVE

To examine race and ethnic differences in the importance of obesity for social integration using the National Longitudinal Study of Adolescent Health (Add Health).

DESIGN

A cross-sectional study utilizing survey-adjusted statistics and multivariate logistic and linear regression models. Models were stratified by sex and included interaction terms capturing race, ethnicity and obesity.

SETTING

United States of America.

PARTICIPANTS

A nationally representative sample of 15,355 respondents grades 7 through 12 who participated in both the In-School and In-Home Wave I surveys of Add Health.

MAIN OUTCOME MEASURES

Four self-reported and schoolmate-reported indicators of social integration.

RESULTS

The consequences of obesity for social integration are greatest for White adolescents, who were selected by almost 2 fewer schoolmates as friends and had half the odds of having their friendships reciprocated compared with non-obese White adolescents. The social disadvantage of obesity was lower for non-White adolescents; though they are selected by significantly fewer schoolmates as friends and were less likely to have their friendships reciprocated, they did not face additional discrimination from being both obese and minority.

CONCLUSIONS

There are significant differences between obese and non-obese adolescents by race and ethnicity in friendships. As friendships are among the most valued assets in adolescence, understanding the impact of obesity on access to friendships for diverse adolescents is a necessary component to understanding the complex motivations that guide health-related behavior at these formative ages.

Weight change and workplace absenteeism in the HealthWorks study

OBJECTIVE

Little is known about the relationship between weight change and workplace absenteeism. The purpose of this study was to examine the degree to which weight change predicted 2-year absenteeism.

METHODS

A longitudinal analysis of 1,228 employees enrolled in a worksite-randomized controlled trial was performed. Participants were all working adults in the Minneapolis, MN, area (USA).

RESULTS

The final model indicated a significant interaction between weight change and baseline BMI. The difference in absenteeism ranged from (mean ± SE) 3.2 ± 1.2 days among healthy weight employees who maintained their weight to 6.6 ± 1.1 days among obese employees who gained weight (and slightly higher among healthy weight employees who lost weight). The adjusted model also indicated that participants who were male, not depressed, nonsmokers, and had lower baseline absenteeism had significantly less workplace absenteeism relative to participants who were female, depressed, smokers, and had higher baseline absenteeism.

CONCLUSION

Absenteeism was generally low in this sample, but healthy weight employees who maintained their body weight over 2 years had the fewest number of sick days. More research is needed in this area, but future workforce attendance interventions may be improved by focusing on the primary prevention of weight gain in healthy weight employees.

The relationship between smoking, body weight, body mass index, and dietary intake among Thai adults: results of the national Thai Food Consumption Survey

This study examined the relationship between dietary intake, body weight, and body mass index (BMI) in adult Thais as a function of smoking status. A cross-sectional, nationally representative survey using health and dietary questionnaires and anthropometric measurements were used. Participants were 7858 Thai adults aged 18 years and older recruited from 17 provinces in Thailand. Results demonstrated that smoking is associated with lower weights and BMI. However, when smokers were stratified by smoking intensity, there was no dose-response relationship between smoking and body weight. There is no conclusive explanation for weight differences across smoking groups in this sample, and the results of the present study did not clearly support any of the purported mechanisms for the differences in body weight or BMI. In addition, because the substantial negative health consequences of smoking are far stronger than those associated with modest weight differences, smoking cannot be viewed as an appropriate weight management strategy.

Jejunal linoleic acid infusions require GLP-1 receptor signaling to inhibit food intake: implications for the effectiveness of Roux-en-Y gastric bypass

Roux-en-Y gastric bypass surgery results in sustained decreases in food intake and weight loss. A key component is likely the direct delivery of nutrients to the jejunum and resulting changes in levels of gut peptide secretion. Prior work modeling this aspect of the surgery has shown that small-volume, prolonged jejunal infusions of linoleic acid (LA) produce sustained decreases in food intake and weight loss. LA infusions also significantly elevate plasma glucagon-like peptide-1 (GLP-1) levels. To assess a role for the increased circulating GLP-1 in the feeding suppression, we examined the effect of prolonged peripheral minipump administration of the GLP-1 receptor antagonist exendin 9-39 (Ex 9) on the feeding suppression produced by jejunal LA. Using a 2 × 2 design, we infused either saline or LA in the jejunum (7 h/day, 11.4 kcal) for 5 days with a subset of animals from each group receiving either saline or Ex 9 (25 pmol·kg(-1)·min(-1)) continuously via a minipump. The antagonist alone had no effect on food intake. LA reduced daily food intake greatly in excess of the kilocalories infused. Ex 9 completely blocked the feeding suppression produced by the jejunal LA infusion. Ex 9 also attenuated the increase in plasma GLP-1 induced by jejunal LA infusions. These data demonstrate that endogenous GLP-1 receptor signaling is necessary for the reduction in food intake produced by jejunal LA infusions. Whether increased secretion of additional gut peptides is also necessary for such suppressions remains to be determined.

Central nervous control of energy and glucose balance: focus on the central melanocortin system

Studies have suggested that manipulations of the central melanocortin circuitry by pharmacological agents produce robust effects on the regulation of body weight and glucose homeostasis. In this review, we discuss recent findings from genetic mouse models that have further established the physiological relevance of this circuitry in the context of glucose and energy balance. In addition, we will discuss distinct neuronal populations that respond to central melanocortins to regulate food intake, energy expenditure, insulin sensitivity, and insulin secretion, respectively. Finally, multiple hormonal and neural cues (e.g., leptin, estrogen, and serotonin) that use the melanocortin systems to regulate energy and glucose homeostasis will be reviewed. These findings suggest that targeting the specific branches of melanocortin circuits may be potential avenues to combat the current obesity and diabetes epidemics.

Body weight relationships in early marriage. Weight relevance, weight comparisons, and weight talk

This investigation uncovered processes underlying the dynamics of body weight and body image among individuals involved in nascent heterosexual marital relationships in Upstate New York. In-depth, semi-structured qualitative interviews conducted with 34 informants, 20 women and 14 men, just prior to marriage and again one year later were used to explore continuity and change in cognitive, affective, and behavioral factors relating to body weight and body image at the time of marriage, an important transition in the life course. Three major conceptual themes operated in the process of developing and enacting informants' body weight relationships with their partner: weight relevance, weight comparisons, and weight talk. Weight relevance encompassed the changing significance of weight during early marriage and included attracting and capturing a mate, relaxing about weight, living healthily, and concentrating on weight. Weight comparisons between partners involved weight relativism, weight competition, weight envy, and weight role models. Weight talk employed pragmatic talk, active and passive reassurance, and complaining and critiquing criticism. Concepts emerging from this investigation may be useful in designing future studies of and approaches to managing body weight in adulthood.

Fat-free weight prediction in morbidly obese females

Purpose

Precise estimation of creatinine clearance in obese individuals relies on the appropriate assessment of lean body weight (LBW). Anthropometric methods of predicting LBW have not been validated in morbidly obese populations.

Patients and methods

Using an existing dataset of anthropometric data for a female cohort with morbid obesity who had undergone measured FFW with dual energy absorptiometry, we evaluated the performance of five previously reported estimating equations for the prediction of LBW. Linear regression was used to derive a new LBW prediction formula and was then compared with the other formulae.

Results

Seventy females (mean [standard deviation] age, weight, and body mass index 43.0 [11.0] years, 128.1 [13.8] kg, and 48.3 [4.8] kg/m², respectively) were identified. LBW as estimated by the method of Garrow and Webster correlated well (r = 0.87) with measured mass while demonstrating the highest accuracy, best precision, and smallest bias (93%, 2.1 kg, and 2.9 kg, respectively; P < 0.0001 for all comparisons). The derived formula further improved bias, precision, and accuracy.

Conclusion

Among females with morbid obesity, most previously reported estimating equations for LBW predicted FFW poorly. These findings have important clinical implications for the assessment of kidney function and for safe and effective drug dosing.

The effect of body weight on adolescent sexual activity

Recent research suggests that overweight females suffer penalties in the labor and marriage markets, while overweight males do not. This study explores whether similar gender differences in the effect of body weight exist in what Cawley et al. (2006) labeled 'the adolescent sex market'. Drawing on data from the National Longitudinal Study of Adolescent Health, we use fixed effects and instrumental variables identification strategies to estimate the relationship between body weight and sexual activity. We find evidence that increased body weight lowers the probability that female adolescents become sexually active. In contrast, there is little evidence of a causal relationship between body weight and sexual activity for male adolescents.

Chronic airflow limitation in a rural Indian population: etiology and relationship to body mass index

Purpose

Respiratory conditions remain a source of morbidity globally. As such, this study aimed to explore factors associated with the development of airflow obstruction (AFO) in a rural Indian setting and, using spirometry, study whether underweight is linked to AFO.

Methods

Patients > 35 years old attending a rural clinic in West Bengal, India, took a structured questionnaire, had their body mass index (BMI) measured, and had spirometry performed by an ancillary health care worker.

Results

In total, 416 patients completed the study; spirometry was acceptable for analysis of forced expiratory volume in 1 second in 286 cases (69%); 16% were noted to exhibit AFO. Factors associated with AFO were: increasing age (95% confidence interval (CI) 0.004–0.011; P = 0.005), smoking history (95% CI 0.07–0.174; P = 0.006), male gender (95% CI 0.19–0.47; P = 0.012), reduced BMI (95% CI 0.19–0.65; P = 0.02), and occupation (95% CI 0.12–0.84; P = 0.08). The mean BMI in males who currently smoked (n = 60; 19.29 kg/m²; standard deviation [SD] 3.46) was significantly lower than in male never smokers (n = 33; 21.15 kg/m² SD 3.38; P < 0.001). AFO was observed in 27% of subjects with a BMI <18.5 kg/m², falling to 13% with a BMI ≥18.5 kg/m² (P = 0.013). AFO was observed in 11% of housewives, 22% of farm laborers, and 31% of cotton/jute workers (P = 0.035).

Conclusion

In a rural Indian setting, AFO was related to advancing age, current or previous smoking, male gender, reduced BMI, and occupation. The data also suggest that being under-weight is linked with AFO and that a mechanistic relationship exists between low body weight, smoking tobacco, and development of AFO.

Ex-premature infant boys with hypospadias are similar in size to age-matched, ex-premature infant boys without hypospadias

OBJECTIVE

Studies have postulated that hypospadias, prematurity, and low birth weight are linked by defects in androgen signaling. To determine whether premature, hypospadiac boys are small and remain so, we compared their size at birth and at hypospadias repair to premature boys who underwent post-neonatal circumcision.

METHODS

We identified premature boys admitted to Texas Children's Hospital who underwent either hypospadias repair or circumcision after 4 months of age. Age, weight, and height at birth and surgery were recorded.

RESULTS

Fifty-four boys had hypospadias and 34 did not. For hypospadiac boys, the mean birth weight and age, height, and weight at surgery were lower than for boys without hypospadias. More importantly, length-for-age and weight-for-age percentiles were also lower for hypospadiac boys. When subset analysis was performed on boys younger than 2 years at surgery, however, there were no significant differences in height or weight between hypospadiac and non-hypospadiac boys.

CONCLUSION

Our series suggests that premature, hypospadiac boys are born smaller than age-matched, non-hypospadiac controls. However, there were no age-corrected size differences between hypospadiac and non-hypospadiac boys at surgery. This implies that hypospadiac boys exhibit post-neonatal 'rebound' growth. Global growth deficits, if any, do not persist in hypospadiac boys.

The association of psoriasis and elevated blood lipids in overweight and obese children

OBJECTIVE

To investigate whether obesity and cardiovascular risk factors are associated with psoriasis in children and adolescents.

STUDY DESIGN

For this population-based, cross-sectional study, measured weight and height, laboratory data, and psoriasis diagnoses were extracted from electronic medical records of 710,949 patients age 2 to 19 years enrolled in an integrated health plan. Weight class was assigned on the basis of body mass index-for-age.

RESULTS

The OR for psoriasis was 0.68, 1.00, 1.31, 1.39, and 1.78 (95% CI, 1.49 to 2.14) for underweight, normal-weight, overweight, moderately obese, and extremely obese children, respectively (P for trend < .001). The OR for psoriasis treated with systemic therapy or phototherapy as an indicator of severe or widespread psoriasis was 0.00, 1.00, 2.78, 2.93, and 4.19 (95% CI, 1.81 to 9.68) for underweight, normal-weight, overweight, moderately obese, and extremely obese children, respectively (P for trend < .003). In adolescents, mean total cholesterol, low-density lipoprotein cholesterol, triglycerides, and alanine aminotransferase were significantly higher in children with psoriasis compared with children without psoriasis after adjustment for body mass index.

CONCLUSION

Overweight and obesity are associated with higher odds of psoriasis in youths. Independent of body weight, adolescent patients with psoriasis have higher blood lipids. These data suggest that pediatricians and dermatologists should screen youths with psoriasis for cardiovascular disease risk factors.

Influence of body weight and type of chow on the sensitivity of rats to the behavioral effects of the direct-acting dopamine-receptor agonist quinpirole

RATIONALE

Amount and type of food can alter dopamine systems and sensitivity to drugs acting on those systems.

OBJECTIVES

This study examined whether changes in body weight, food type, or both body weight and food type contribute to these effects.

METHODS

Rats had free or restricted access (increasing, decreasing, or maintaining body weight) to standard (5.7% fat) or high-fat (34.3%) chow.

RESULTS

In rats gaining weight with restricted or free access to high-fat chow, both limbs of the quinpirole yawning dose-response curve (0.0032-0.32 mg/kg) shifted leftward compared with rats eating standard chow. Restricting access to standard or high-fat chow (maintaining or decreasing body weight) decreased or eliminated quinpirole-induced yawning; within 1 week of resuming free feeding, sensitivity to quinpirole was restored, although the descending limb of the dose-response curve was shifted leftward in rats eating high-fat chow. These are not likely pharmacokinetic differences because quinpirole-induced hypothermia was not different among groups. PG01037 and L-741,626 antagonized the ascending and descending limbs of the quinpirole dose-response curve in rats eating high-fat chow, indicating D3 and D2 receptor mediation, respectively. Rats eating high-fat chow also developed insulin resistance.

CONCLUSIONS

These results show that amount and type of chow alter sensitivity to a direct-acting dopamine-receptor agonist with the impact of each factor depending on whether body weight increases, decreases, or is maintained. These data demonstrate that feeding conditions, perhaps related to insulin and insulin sensitivity, profoundly impact the actions of drugs acting on dopamine systems.

Weight gain since menopause and its associations with weight loss maintenance in obese postmenopausal women

Objective

To examine the association between weight gain since menopause and weight regain after a weight loss program.

Methods

Participants were 19 obese women who participated in a 15-week weight loss program and a 12-month follow-up. Main outcomes were: body composition, resting metabolic rate, energy intake, energy expenditure, and weight regain at follow-up.

Results

All body composition measures significantly decreased after intervention (all P ≤ 0.01) while all measures of fatness increased significantly after the 12-month follow-up (P ≤ 0.01). Body weight gain since menopause was associated with body weight regain (r = 0.65; P = 0.003) after follow-up even after adjustment for confounders.

Conclusion

Weight gain since menopause is associated with body weight regain following the weight loss program. Therefore, weight gain since menopause should be considered as a factor influencing weight loss maintenance in older women.

Adipose-specific deletion of Src homology phosphatase 2 does not significantly alter systemic glucose homeostasis

The SH2 domain-containing protein-tyrosine phosphatase Src homology phosphatase 2 (Shp2) has been implicated in a variety of growth factor signaling pathways, but its metabolic role in some peripheral insulin-responsive tissues remains unknown. To address the metabolic function of Shp2 in adipose tissue, we generated mice with adipose-specific Shp2 deletion using adiponectin-Cre transgenic mice. We then analyzed insulin sensitivity, glucose tolerance, and body mass in adipose-specific Shp2-deficient and control mice on regular chow and high-fat diet (HFD). Control mice on HFD exhibited increased Shp2 expression in various adipose depots compared with those on regular chow. Adiponectin-Cre mice enabled efficient and specific deletion of Shp2 in adipose tissue. However, adipose Shp2 deletion did not significantly alter body mass in mice on chow or HFD. In addition, mice with adipose Shp2 deletion exhibited comparable insulin sensitivity and glucose tolerance compared with controls. Consistent with this, basal and insulin-stimulated Erk and Akt phosphorylations were comparable in adipose tissue of Shp2-deficient and control mice. Our findings indicate that adipose-specific Shp2 deletion does not significantly alter systemic insulin sensitivity and glucose homeostasis.

Impact of small group size on neighbourhood influences in multilevel models

BACKGROUND

Given the growing availability of multilevel data from national surveys, researchers interested in contextual effects may find themselves with a small number of individuals per group. Although there is a growing body of literature on sample size in multilevel modelling, few have explored the impact of group sizes of less than five.

METHODS

In a simulated analysis of real data, the impact of a group size of less than five was examined on both a continuous and dichotomous outcome in a simple two-level multilevel model. Models with group sizes one to five were compared with models with complete data. Four different linear and logistic models were examined: empty models; models with a group-level covariate; models with an individual-level covariate and models with an aggregated group-level covariate. The study evaluated further whether the impact of small group size differed depending on the total number of groups.

RESULTS

When the number of groups was large (N=459), neither fixed nor random components were affected by small group size, even when 90% of tracts had only one individual per tract and even when an aggregated group-level covariate was examined. As the number of groups decreased, the SE estimates of both fixed and random effects were inflated. Furthermore, group-level variance estimates were more affected than were fixed components.

CONCLUSIONS

Datasets in which there is a small to moderate number of groups, with the majority of very small group size (n<5), size may fail to find or even consider a group-level effect when one may exist and also may be underpowered to detect fixed effects.

Differential effects of glucocorticoids on energy homeostasis in Syrian hamsters

Syrian hamsters, like many humans, increase food intake and body adiposity in response to stress. We hypothesized that glucocorticoids (cortisol and corticosterone) mediate these stress-induced effects on energy homeostasis. Because Syrian hamsters are dual secretors of cortisol and corticosterone, differential effects of each glucocorticoid on energy homeostasis were investigated. First, adrenal intact hamsters were injected with varying physiological concentrations of cortisol, corticosterone, or vehicle to emulate our previously published defeat regimens (i.e., 1 injection/day for 5 days). Neither food intake nor body weight was altered following glucocorticoid injections. Therefore, we investigated the effect of sustained glucocorticoid exposure on energy homeostasis. This was accomplished by implanting hamsters with supraphysiological steady-state pellets of cortisol, corticosterone, or cholesterol as a control. Cortisol, but not corticosterone, significantly decreased food intake, body mass, and lean and fat tissue compared with controls. Despite decreases in body mass and adiposity, cortisol significantly increased circulating free fatty acids, triglyceride, cholesterol, and hepatic triglyceride concentrations. Although corticosterone did not induce alterations in any of the aforementioned metabolic end points, Syrian hamsters were responsive to the effects of corticosterone since glucocorticoids both induced thymic involution and decreased adrenal mass. These findings indicate that cortisol is the more potent glucocorticoid in energy homeostasis in Syrian hamsters. However, the data suggest that cortisol alone does not mediate stress-induced increases in food intake or body mass in this species.

Food intake, metabolism and homeostasis

This tribute to Bart Hoebel briefly reviews the following topics. Metabolic processes are intimately intertwined with food intake as well as drug taking. Changes in any of these processes can be adequately adjusted to the environment to preclude major perturbations in homeostatically-regulated systems, but only if the environment is predictable. Learning plays a critical role in adapting these processes to specific situations. The regulatory context plays a critical role in how metabolism and food intake interact.

Empirical Growth Curve Estimation Using Sigmoid Sub-functions that Adjust Seasonal Compensatory Growth for Male Body Weight of Thoroughbred Horses

Thoroughbred horses are seasonal mating animals, raised in northern regions or countries. Foals born yearly in spring generally show a typical seasonal compensatory growth pattern, in which their growth rate declines in the first winter and increases in the next spring. In this study, a new empirical adjustment approach is proposed to adjust for this compensatory growth when growth curve equations are estimated, by using 1,633 male body weights of Thoroughbreds as an illustrating example. Based on general Richards growth curve equation, a new growth curve equation was developed and fit to the weight-age data. The new growth curve equation had a sigmoid sub-function that can adjust the compensatory growth, combined with the Richards biological parameter responsible for the maturity of animals. The unknown parameters included in the equations were estimated by SAS NLMIXED procedure. The goodness of fit was examined by using Akaike’s Information Criterion (AIC). The AIC values decreased from 13,053 (general Richards equation) to 12,794 (the newly developed equation), indicating the better fit of the new equation to the weight-age data. The shape of the growth curve was improved during the period of compensatory growth. The proposed method is one of the useful approaches for adjusting seasonal compensatory growth in growth curve estimations for Thoroughbreds, and for their management during the compensatory period. Based on this approach, the optimal growth curve equations can be estimated also for female body weight of Thoroughbreds or other growth traits affected by seasonal compensatory growth.

Integration of population pharmacokinetics and pharmacogenetics: an aid to optimal nevirapine dose selection in HIV-infected individuals

BACKGROUND

Nevirapine is metabolized by CYP2B6 and polymorphisms within the CYP2B6 gene partly explain inter-patient variability in pharmacokinetics. The aim of this study was to model the complex relationship between nevirapine exposure, weight and genetics (based on combined analysis of CYP2B6 516G > T and 983T > C single nucleotide polymorphisms).

METHODS

Non-linear mixed-effects modelling was used to estimate pharmacokinetic parameters from 275 patients. Simulations of the nevirapine concentration profile were performed with dosing regimens of 200 mg twice daily and 400 mg once daily for individuals with body weights of 50, 70 and 90 kg in combination with CYP2B6 genetic variation.

RESULTS

A one-compartment model with first-order absorption best described the data. Population clearance was 3.5 L/h with inter-patient variability of 24.6%. 516T homozygosity and 983C heterozygosity were associated with 37% and 40% lower clearance, respectively. Body weight was the only significant demographic factor influencing clearance, which increased by 5% for every 10 kg increase. For individuals with higher body weight, once-daily nevirapine was associated with a greater risk of sub-therapeutic drug exposure than a twice-daily regimen. This risk was offset in individuals who were 516T homozygous or 983C heterozygous in which drug exposure was optimal for  >  95% of patients with body weight of ≤ 70 kg.

CONCLUSIONS

The data suggest that a 400 mg once-daily dose could be implemented in accordance with CYP2B6 polymorphism and body weight. However, the use of nevirapine once daily (immediate release; off-label) in the absence of therapeutic drug monitoring is not recommended due to the risk of inadequate exposure to nevirapine in a high proportion of patients. There are different considerations for the extended-release formulation (nevirapine XR) that demonstrate minimal peak-to-trough fluctuations in plasma nevirapine levels.

Architecture of energy balance traits in emerging lines of the Collaborative Cross

The potential utility of the Collaborative Cross (CC) mouse resource was evaluated to better understand complex traits related to energy balance. A primary focus was to examine if genetic diversity in emerging CC lines (pre-CC) would translate into equivalent phenotypic diversity. Second, we mapped quantitative trait loci (QTL) for 15 metabolism- and exercise-related phenotypes in this population. We evaluated metabolic and voluntary exercise traits in 176 pre-CC lines, revealing phenotypic variation often exceeding that seen across the eight founder strains from which the pre-CC was derived. Many phenotypic correlations existing within the founder strains were no longer significant in the pre-CC population, potentially representing reduced linkage disequilibrium (LD) of regions harboring multiple genes with effects on energy balance or disruption of genetic structure of extant inbred strains with substantial shared ancestry. QTL mapping revealed five significant and eight suggestive QTL for body weight (Chr 4, 7.54 Mb; CI 3.32-10.34 Mb; Bwq14), body composition, wheel running (Chr 16, 33.2 Mb; CI 32.5-38.3 Mb), body weight change in response to exercise (1: Chr 6, 77.7Mb; CI 72.2-83.4 Mb and 2: Chr 6, 42.8 Mb; CI 39.4-48.1 Mb), and food intake during exercise (Chr 12, 85.1 Mb; CI 82.9-89.0 Mb). Some QTL overlapped with previously mapped QTL for similar traits, whereas other QTL appear to represent novel loci. These results suggest that the CC will be a powerful, high-precision tool for examining the genetic architecture of complex traits such as those involved in regulation of energy balance.

Broad segmental progeroid changes in short-lived Ercc1(-/Δ7) mice

Genome maintenance is considered a prime longevity assurance mechanism as apparent from many progeroid human syndromes that are caused by genome maintenance defects. The ERCC1 protein is involved in three genome maintenance systems: nucleotide excision repair, interstrand cross-link repair, and homologous recombination. Here we describe in-life and post-mortem observations for a hypomorphic Ercc1 variant, Ercc1(-/Δ7), which is hemizygous for a single truncated Ercc1 allele, encoding a protein lacking the last seven amino acids. Ercc1(-/Δ7) mice were much smaller and median life span was markedly reduced compared to wild-type siblings: 20 and 118 weeks, respectively. Multiple signs and symptoms of aging were found to occur at an accelerated rate in the Ercc1(-/Δ7) mice as compared to wild-type controls, including a decline in weight of both whole body and various organs, numerous histopathological lesions, and immune parameters. Together they define a segmental progeroid phenotype of the Ercc1(-/Δ7) mouse model.

Food reward, hyperphagia, and obesity

Given the unabated obesity problem, there is increasing appreciation of expressions like "my eyes are bigger than my stomach," and recent studies in rodents and humans suggest that dysregulated brain reward pathways may be contributing not only to drug addiction but also to increased intake of palatable foods and ultimately obesity. After describing recent progress in revealing the neural pathways and mechanisms underlying food reward and the attribution of incentive salience by internal state signals, we analyze the potentially circular relationship between palatable food intake, hyperphagia, and obesity. Are there preexisting individual differences in reward functions at an early age, and could they be responsible for development of obesity later in life? Does repeated exposure to palatable foods set off a cascade of sensitization as in drug and alcohol addiction? Are reward functions altered by secondary effects of the obese state, such as increased signaling through inflammatory, oxidative, and mitochondrial stress pathways? Answering these questions will significantly impact prevention and treatment of obesity and its ensuing comorbidities as well as eating disorders and drug and alcohol addiction.

Dosing of unfractionated heparin in obese patients with venous thromboembolism

BACKGROUND

Aggressive weight-based dosing guidelines help achieve prompt therapeutic anticoagulation in patients with venous thromboembolism (VTE). While obese patients with VTE face an increased risk of recurrence, physicians typically resist prescribing doses two to three times the usual dose because of concern about bleeding complications.

OBJECTIVE

To examine the use of unfractionated heparin in obese patients with VTE at an academic teaching hospital in order to document the extent and pattern of underprescribing in this high-risk patient population.

DESIGN

Three-year, cross-sectional consecutive case series.

PATIENTS

Adult inpatients with VTE and a body mass index ≥30 kg/m(2) who were treated with unfractionated heparin.

MEASUREMENTS

Time to achievement of therapeutic anticoagulation (activated partial thromboplastin time >60 s) and gap between recommended and prescribed heparin doses.

RESULTS

Time to attainment of therapeutic anticoagulation exceeded 24 h in 29% of study patients (n = 84) and exceeded 48 h in 14% of patients. In 75 patients (89%), the prescribed bolus dose fell below the recommended dose of 80 units/kg, and in 64 patients (76%) the initial continuous infusion fell more than 100 units/h below--in some cases more than 1000 units/h below--the recommended dose of 18 units/kg/h. There was a significant correlation between time to therapeutic anticoagulation and initial infusion dose (Spearman r = -0.27; p < 0.02). Each decrease of 1 unit/kg/h translated to a delay ranging from about 0.75 h to 1.5 h over the range of prescribed doses (6 to 22 units/kg/h).

CONCLUSIONS

A substantial proportion of obese patients treated with unfractionated heparin experienced a delay >24 h in achieving adequate anticoagulation, and the vast majority received an inadequate heparin bolus or initial continuous infusion (or both) according to current dosing guidelines.

Chronic injection of pansomatostatin agonist ODT8-SST differentially modulates food intake and decreases body weight gain in lean and diet-induced obese rats

The aim of this study was to investigate the central actions of the stable pansomatostatin peptide agonist, ODT8-SST on body weight. ODT8-SST or vehicle was acutely (1μg/rat) injected or chronically infused (5μg/rat/d, 14d) intracerebroventricularly and daily food intake, body weight and composition were monitored. In lean rats, neither acute nor chronic ODT8-SST influenced daily food intake while body weight was reduced by 2.2% after acute injection and there was a 14g reduction of body weight gain after 14d compared to vehicle (p<0.01). In diet-induced obese (DIO) rats, chronic ODT8-SST increased cumulative 2-week food intake compared to vehicle (+14%, p<0.05) and also blunted body weight change (-11g, p<0.05). ODT8-SST for 14d reduced lean mass (-22g and -25g respectively, p<0.001) and total water (-19g and -22g respectively, p<0.001) in lean and DIO rats and increased fat mass in DIO (+16g, p<0.001) but not lean rats (+1g, p>0.05) compared to vehicle. In DIO rats, ODT8-SST reduced ambulatory (-27%/24h, p<0.05) and fine movements (-38%, p<0.01) which was associated with an increased positive energy balance compared to vehicle (+50g, p<0.01). Chronic central somatostatin receptor activation in lean rats reduces body weight gain and lean mass independently of food intake which is likely related to growth hormone inhibition. In DIO rats, ODT8-SST reduces lean mass but promotes food intake and fat mass, indicating differential responsiveness to somatostatin under obese conditions.

The effects of physiological adaptations to calorie restriction on global cell proliferation rates

Calorie restriction (CR) reduces the rate of cell proliferation in mitotic tissues. It has been suggested that this reduction in cell proliferation may mediate CR-induced increases in longevity. However, the mechanisms that lead to CR-induced reductions in cell proliferation rates remain unclear. To evaluate the CR-induced physiological adaptations that may mediate reductions in cell proliferation rates, we altered housing temperature and access to voluntary running wheels to determine the effects of food intake, energy expenditure, percent body fat, and body weight on proliferation rates of keratinocytes, liver cells, mammary epithelial cells, and splenic T-cells in C57BL/6 mice. We found that ∼20% CR led to a reduction in cell proliferation rates in all cell types. However, lower cell proliferation rates were not observed with reductions in 1) food intake and energy expenditure in female mice housed at 27°C, 2) percent body fat in female mice provided running wheels, or 3) body weight in male mice provided running wheels compared with ad libitum-fed controls. In contrast, reductions in insulin-like growth factor I were associated with decreased cell proliferation rates. Taken together, these data suggest that CR-induced reductions in food intake, energy expenditure, percent body fat, and body weight do not account for the reductions in global cell proliferation rates observed in CR. In addition, these data are consistent with the hypothesis that reduced cell proliferation rates could be useful as a biomarker of interventions that increase longevity.

Proximal femur structural geometry changes during and following lactation

Human lactation is associated with transient decreases in bone mineral density (BMD). Bone strength is related to both mass and structural geometry. This study investigated longitudinal changes of hip bone strength during lactation using hip structural analysis (HSA), which determines hip structural geometry (including areal BMD, BMDa) from dual-energy X-ray absorptiometry scans (DXA). Forty-eight lactating women were studied longitudinally at the proximal femur using DXA at approximately 2 weeks postpartum, peak-lactation and post-lactation. Nonpregnant, nonlactating women (NPNL, n=23) were studied concurrently at baseline and after 1 year. Hip scans were analysed using HSA at the narrow neck, intertrochanter and proximal shaft. No significant change (>0.05) was observed in NPNL women for any measurement. In contrast, for lactating women BMDa decreased significantly from 2 weeks postpartum to peak-lactation at narrow neck (-2.8%), intertrochanter (-3.2%) and shaft (-1.4%). Cross-sectional area (CSA) decreased at narrow neck (-3.4%) and intertrochanter (-2.7%). There were no significant changes in bone width. Section modulus decreased at intertrochanter (-2.1%). At shaft, cortical thickness decreased (-1.7%) and buckling ratio increased (2.3%). By post-lactation, measurements were not significantly different from 2 weeks postpartum except for decrements in BMDa (-1.1%) and CSA (-1.2%) at the shaft. During the study, lactating women lost 5% of their body weight. Adjusting for weight changes decreased the magnitude and significance of HSA changes at peak-lactation and by post-lactation there were no significant differences from 2 weeks postpartum. Calcium intake was not a significant predictor of changes in HSA variables. In conclusion, lactation is associated with significant but transient changes in hip BMD and structural geometry. Changes in body weight but not calcium intake were associated with these changes. These small changes at the hip during lactation occurred mainly at internal surfaces and had minimal impact on bending or compressive strength.

Increasing effect of body weight perception on suicidal ideation among young Korean women: Findings from the Korea National Health and Nutrition Examination Survey 2001 and 2005

OBJECTIVE

To examine the prevalence of actual and perceived overweight and to compare the mediating effect of perceived overweight on the relationship between actual overweight and suicidal ideation among young Korean women between 2001 and 2005.

METHODS

Data were gathered from the 2001 and 2005 Korean National Health and Nutrition Examination Surveys involving a nationally representative sample of young women (568 in 2001 and 385 in 2005) aged 20-29 years.

RESULTS

Over the 5-year period, the prevalence of actual overweight (body mass index ≥23 kg/m(2)) and perceived overweight increased by 10.5% and 22.8%, respectively. The discrepancy between actual and perceived body weights was much wider in 2005 than in 2001. After controlling for covariates (age, marital status, educational attainment, employment status, smoking status, alcohol consumption, and regular exercise), overweight women were more likely to think about suicide than their normal-weight counterparts in both periods. However, in both periods, the association between overweight and suicidal ideation became nonsignificant when perceived weight was considered. In both periods, a self-perception of overweight was associated with an increased risk of suicidal ideation, but the association was much stronger in 2005 than in 2001.

CONCLUSION

This study suggests a need for educational programs or effective treatments to help young women who perceive themselves as overweight to reduce the potential risk of suicidal ideation in later life.

Body weight reducing effect of oral boric acid intake

BACKGROUND

Boric acid is widely used in biology, but its body weight reducing effect is not researched.

METHODS

Twenty mice were divided into two equal groups. Control group mice drank standard tap water, but study group mice drank 0.28mg/250ml boric acid added tap water over five days. Total body weight changes, major organ histopathology, blood biochemistry, urine and feces analyses were compared.

RESULTS

Study group mice lost body weight mean 28.1% but in control group no weight loss and also weight gained mean 0.09% (p<0.001). Total drinking water and urine outputs were not statistically different. Cholesterol, LDL, AST, ALT, LDH, amylase and urobilinogen levels were statistically significantly high in the study group. Other variables were not statistically different. No histopathologic differences were detected in evaluations of all resected major organs.

CONCLUSION

Low dose oral boric acid intake cause serious body weight reduction. Blood and urine analyses support high glucose, lipid and middle protein catabolisms, but the mechanism is unclear.

Opposing alterations in anxiety and species-typical behaviours in serotonin transporter overexpressor and knockout mice

Human gene association studies have produced conflicting findings regarding the relationship between the 5-HT transporter (5-HTT) and anxiety. In the present study genetically modified mice were utilised to examine the effects of changes in 5-HTT expression on anxiety. In addition, the influence of 5-HTT expression on two innate "species-typical" behaviours (burrowing and marble burying) and body weight was explored. Across a range of models, 5-HTT overexpressing mice displayed reduced anxiety-like behaviour whilst 5-HTT knockout mice showed increased anxiety-like behaviour, compared to wildtype controls. In tests of species-typical behaviour 5-HTT overexpressing mice showed some facilitation whilst 5-HTT knockout mice were impaired. Reciprocal effects were also seen on body weight, as 5-HTT overexpressors were lighter and 5-HTT knockouts were heavier than wildtype controls. These findings show that variation in 5-HTT gene expression produces robust changes in anxiety and species-typical behaviour. Furthermore, the data add further support to findings that variation of 5-HTT expression in the human population is linked to changes in anxiety-related personality traits.

Influence of obesity and gender on the postural stability during upright stance

OBJECTIVE

To assess the influence of BMI group (lean/overweight/obese) and gender on the postural sway of adults and adolescents during quiet upright stance.

METHODS

90 women and 90 men, aged 12 to 67 years old, accepted to participate. The center of pressure during quiet upright stance was recorded using a force platform, during 4 conditions (eyes open/closed on hard/soft surface). Statistical analysis was performed using multivariate analysis of covariance.

RESULTS

During recordings on hard surface, closing the eyes produced a larger increase of sway on obese subjects than on lean and overweight subjects, with a larger increase on the length and the area of sway. Although gender differences were found during the four sensory conditions, no interaction was observed between the BMI group and the gender. These results were not related to the age of the subjects.

CONCLUSION

Compared to non-obese subjects, the postural stability of obese subjects may be more vulnerable when vision is not available, with no influence of the gender.

Plasma phospholipid long-chain n-3 polyunsaturated fatty acids and body weight change

OBJECTIVE

We investigated the association between the proportion of long-chain n-3 polyunsaturated fatty acids (PUFA) in plasma phospholipids from blood samples drawn at enrollment and subsequent change in body weight. Sex, age, and BMI were considered as potential effect modifiers.

METHOD

A total of 1,998 women and men participating in the European Prospective Investigation into Cancer and Nutrition (EPIC) were followed for a median of 4.9 years. The associations between the proportion of plasma phospholipid long-chain n-3 PUFA and change in weight were investigated using mixed-effect linear regression.

RESULTS

The proportion of long-chain n-3 PUFA was not associated with change in weight. Among all participants, the 1-year weight change was -0.7 g per 1% point higher long-chain n-3 PUFA level (95% confidence interval: -20.7 to 19.3). The results when stratified by sex, age, or BMI groups were not systematically different.

CONCLUSION

The results of this study suggest that the proportion of long-chain n-3 PUFA in plasma phospholipids is not associated with subsequent change in body weight within the range of exposure in the general population.

Impact of enhanced sensory input on treadmill step frequency: infants born with myelomeningocele

PURPOSE

To determine the effect of enhanced sensory input on the step frequency of infants with myelomeningocele (MMC) when supported on a motorized treadmill.

METHODS

Twenty-seven infants aged 2 to 10 months with MMC lesions at, or caudal to, L1 participated. We supported infants upright on the treadmill for 2 sets of 6 trials, each 30 seconds long. Enhanced sensory inputs within each set were presented in random order and included baseline, visual flow, unloading, weights, Velcro, and friction.

RESULTS

Overall friction and visual flow significantly increased step rate, particularly for the older subjects. Friction and Velcro increased stance-phase duration. Enhanced sensory input had minimal effect on leg activity when infants were not stepping.

CONCLUSIONS

: Increased friction via Dycem and enhancing visual flow via a checkerboard pattern on the treadmill belt appear to be more effective than the traditional smooth black belt surface for eliciting stepping patterns in infants with MMC.

Role of media and peers on body change strategies among adult men: is body size important?

There has been limited previous research that has examined the role of sociocultural influences on body change strategies among adult men. The current study investigated the role of specific types of messages (encouragement, teasing and modelling) from peers and the media on the strategies to change weight among adult men. Differences were evaluated between 526 men aged from 18 to 60 years from three groups (normal weight, overweight and obese) on body image, body change strategies and messages about their body received from peers and the media. Men were primarily drawn from United States, Australia and Europe. Results showed that messages received by men regarding losing weight or increasing muscle size differed according to weight. Body image and media messages were the strongest predictors of losing weight, whereas body image importance and messages from peers were the strongest predictors of increasing muscles. These findings highlight the importance of sociocultural influences on body change strategies among adult males.

The impact of increasing body mass on peak and mean plantar pressure in asymptomatic adult subjects during walking

INTRODUCTION

The implication of high peak plantar pressure on foot pathology in individuals both with and without diabetes has been recognized. The aim of this study was to investigate and clarify the relationship between increasing body mass and peak and mean plantar pressure in an asymptomatic adult population during walking.

METHODS

Thirty adults without any relevant medical history, structural foot deformities or foot posture assessed as highly pronated or supinated, and within a normal body mass index range were included in the study. An experimental, same subjects, repeated measures design was used. Peak and mean plantar pressure were evaluated with the F-Scan in-shoe plantar pressure measurement system under four different loading conditions (0, 5, 10, and 15 kg) simulated with a weighted vest. Pressure data were gathered from three stances utilizing the mid-gait protocol.

RESULTS

There were statistically significant increases in peak pressure between the 10 and 15 kg load conditions compared to the control (0 kg) within the heel and second to fifth metatarsal regions. The first metatarsal and hallux regions only displayed statistically significant increases in peak pressure between 15 kg and the control (0 kg). The midfoot and lesser digits regions did not display any statistically significant differences in peak pressure between any load conditions compared to the control (0 kg). The second to fifth metatarsal region displayed statistically significant increases in mean pressure in the 5, 10 and 15 kg groups compared to the control (0 kg). A statistically significant increase in peak pressure between the 15 kg and control (0 kg) group was evident in all other regions.

CONCLUSION

The relationship between increasing body mass and peak and mean plantar pressure was dependent upon the plantar region. This study provides more detail outlining the response of peak and mean pressure to different loading conditions than previously reported in the literature. Further research including measurement of temporal parameters is warranted.

Significant differences in UK and US female bone density reference ranges

In the United Kingdom (UK), T- and Z-scores are usually calculated using reference ranges derived from United States (US) populations. In the UK arm of a recent randomised trial (International Breast Cancer Intervention Study II (IBIS-II)), substantially, fewer women than expected were recruited into the osteopenic (-2.5<T-score<-1.0) and osteoporotic (T-score<-2.5) arms of the study. The comparison with data from two independent studies showed that UK women aged >45 years with a typical body mass index of 28 kg m(-2) have spine and hip bone mineral density (BMD) 0.6 standard deviation higher than their US counterparts.

INTRODUCTION

Dual energy X-ray absorptiometry (DXA) is widely used for the diagnosis of osteoporosis and to investigate the effect of pharmacological treatments on BMD. In both routine and research settings, it is important that DXA results are correctly interpreted.

METHODS

T- and Z-scores for the first 650 UK Caucasian women enrolled in the IBIS-II study were compared with data from two independent studies of unrelated, unselected UK Caucasian women: (1) 2,382 women aged 18 to 79 recruited to the Twins UK Adult Twin Registry; (2) 431 women aged 21 to 84 with no risk factors for osteoporosis recruited at Guy's Hospital. All DXA measurements were performed on Hologic densitometers. Subjects were divided into six age bands, and T- and Z-scores were calculated using the manufacturer's US reference range for the spine and the National Health and Nutrition Examination Survey III reference range for the femoral neck and total hip.

RESULTS

The overall mean Z-scores for the IBIS-II, Twin, and Guy's groups were: spine: +0.61, +0.29, +0.33; femoral neck: +0.42, +0.36, +0.45; total hip: +0.65, +0.38, +0.39 (all p<0.001 compared with the expected value of 0). The mean body weight of subjects in the three studies was 74.4, 65.5, and 65.4 kg, respectively. Analysis revealed a highly significant relationship between Z-score and weight at each BMD site with a slope of 0.03 kg(-1).

CONCLUSIONS

In general, US spine and hip reference ranges are not suitable for the calculation of Z-scores in UK women. For some research study designs, the differences may significantly influence the pattern of subject recruitment.

Liver fatty acid-binding protein and obesity

While low levels of unesterified long chain fatty acids (LCFAs) are normal metabolic intermediates of dietary and endogenous fat, LCFAs are also potent regulators of key receptors/enzymes and at high levels become toxic detergents within the cell. Elevated levels of LCFAs are associated with diabetes, obesity and metabolic syndrome. Consequently, mammals evolved fatty acid-binding proteins (FABPs) that bind/sequester these potentially toxic free fatty acids in the cytosol and present them for rapid removal in oxidative (mitochondria, peroxisomes) or storage (endoplasmic reticulum, lipid droplets) organelles. Mammals have a large (15-member) family of FABPs with multiple members occurring within a single cell type. The first described FABP, liver-FABP (L-FABP or FABP1), is expressed in very high levels (2-5% of cytosolic protein) in liver as well as in intestine and kidney. Since L-FABP facilitates uptake and metabolism of LCFAs in vitro and in cultured cells, it was expected that abnormal function or loss of L-FABP would reduce hepatic LCFA uptake/oxidation and thereby increase LCFAs available for oxidation in muscle and/or storage in adipose. This prediction was confirmed in vitro with isolated liver slices and cultured primary hepatocytes from L-FABP gene-ablated mice. Despite unaltered food consumption when fed a control diet ad libitum, the L-FABP null mice exhibited age- and sex-dependent weight gain and increased fat tissue mass. The obese phenotype was exacerbated in L-FABP null mice pair fed a high-fat diet. Taken together with other findings, these data suggest that L-FABP could have an important role in preventing age- or diet-induced obesity.

Calcium: a nutrient deserving a special issue

Interest in calcium has continued since the 1980s when its role in promoting bone growth and retention was established in clinical trials of children and postmenopausal women. The human nutrition functions now attributed to calcium have expanded beyond bone health to include other conditions such as body weight maintenance. While most efforts have been focused on the findings that dietary intakes are low, there are emerging data on safety concerns of excess amounts. This Special Issue on calcium nutrition, spanning the lifecycle from critically ill neonates through to older adults, has been written by some of the leading researchers in this field.

Incident sleep disordered breathing in old age

BACKGROUND

Little is known about progression of and risk factors for sleep disordered breathing (SDB) in old age. We prospectively examined elderly volunteers to understand how changes in body weight are related to SDB for a period of 20-30 years.

METHODS

Participants were 30 surviving members of a community-based cohort (mean entry age = 57.8) studied over a median follow-up of 23.4 years. SDB was quantified as the apnea-hypopnea index (AHI) via in-lab polysomnography from 215 nights, representing 733.3 person-years of follow-up. Weights were recorded in kilograms. We used linear regression to derive individual trajectories of AHI and weight regressed on time.

RESULTS

Individuals had relatively low AHI (X = 2.3 [SD = 3.5]) and body mass index (kg/m(2); X = 24.6 [SD = 4.6]) at entry. Rates of change in AHI were characterized by positive slopes and linear increases by least squares regression. Mean rate of change was +0.43 events per hour per year, a 3.3% yearly increase relative to the maximum AHI observed for each case. Within individuals, curve fitting indicated statistically significant AHI increases associated not only with increases, but also decreases, in weight.

CONCLUSIONS

Rates of increase in AHI were larger than for aging reported for other organ systems (eg, autonomic, musculoskeletal, and respiratory), possibly reflecting complex mechanistic determination of SDB in old age. Association between decreased weight and increased SDB with advancing years represents an important "proof of concept," perhaps compatible with failure to maintain airway patency during sleep as a component of generalized muscle weakness in old age.

The effects of a high-caloric protein-rich oral nutritional supplement in patients with chronic heart failure and cachexia on quality of life, body composition, and inflammation markers: a randomized, double-blind pilot study

The prevalence of cardiac cachexia in chronic heart failure is approximately 5% to 15% and 18-month mortality rates can reach 50%. Treatment with angiotensin-converting enzyme inhibitors and beta-blockers may confer some benefit but no proven therapy exists. We tested the effects of an oral nutritional supplement in cachectic patients with heart failure. This was a prospective, randomized, double-blind, placebo-controlled pilot study which randomized 29 patients to a high-caloric (600 kcal) high-protein (20 g) oral nutritional supplement or placebo for a duration of 6 weeks in addition to the patients' usual food intake. At baseline, 6 weeks, and 18 weeks, we measured body weight, quality of life, body composition, heart function, laboratory parameters, and exercise performance. Edema-free body weight increased in 19 of 20 patients receiving intervention at 6 weeks and in 17 of 19 patients at 18 weeks with an average weight gain of 2.0 ± 1.7 kg (3.1 ± 2.4%, p = 0.0001) and 2.3 ± 3.1 kg (3.6 ± 4.7%, p = 0.007) at 6 and 18 weeks, respectively. Most of the weight gain was fat tissue with an absolute gain of 1.5 ± 1.7 kg (p = 0.003) and 1.6 ± 2.7 kg (p = 0.008). A significant improvement in quality of life and decrease in serum levels of tumor necrosis factor-α were observed (p < 0.05 for both). We demonstrated the feasibility of oral nutritional supplement in cachectic patients with heart failure and significant clinical benefit in terms of body size and body composition, laboratory parameters, and quality of life (www.clinicaltrials.gov identifier NCT00654719).

Eating behaviour and body satisfaction in mediterranean children: the role of the parents

Although the prevalence of fully expressed Eating Disorders is rare in young children, childhood eating disturbances are fairly common. Parents can play a facilitating role for the development of overweight and eating problems among their children. The aim of this study is to detect the possible relationships between children’s eating attitudes and behaviour and the parents’ beliefs about eating habits and body shape of their offspring.

This survey was conducted in the area of Arezzo (Italy), on 900 children, aged 7-12, and on their parents/substitute caregivers. The Kids’ Eating Disorder Survey questionnaire, and the CIBUS questionnaire were administered.

A fully expressed Eating Disorder was diagnosed in two kids only. KEDS total score and weight/dissatisfaction subscale score positively correlated with parents’ answers to the following CIBUS’ items (How do you consider the body shape of your son/daughter? How much does your son/daughter eats? Have you ever thought of putting your son/daughter on a diet?). Positive correlations between the children BMI, desired BMI and the aforementioned CIBUS’ items were found.

The prevalence of formal Eating Disorders in children aged 7-12 is low. Children appear to be more preoccupied with their weight than with their body shape. Parents’ beliefs about the offspring’s body shape and eating habits have a relevant impact on children’s eating attitudes and behaviour.

Bullying victimization among underweight and overweight U.S. youth: differential associations for boys and girls

To examine the associations between body weight and physical, verbal, relational, and cyber victimization among U.S. boys and girls in grade 6 through 10. Underweight boys and girls were more likely to be physical and relational victims, respectively. Overweight boys and obese girls were more likely to be verbal victims.

Effect of intradialytic change in plasma volume on blood pressure in patients undergoing maintenance hemodialysis

BACKGROUND

Hypervolemia is a common complication in patients on hemodialysis (HD). To determine the effect of volume change on blood pressure in HD population, this cohort was conducted.

MATERIALS AND METHODS

The study population was composed of 60 non-diabetic patients on maintenance HD, with mean age of 59.95±15.28 years. They were divided into hypertensive group A (n=26) and normotensive group B (n=34). Data were collected by a questionnaire. Pre and post-dialysis blood levels of urea, sodium, total protein, and hemoglobin were measured and intradialytic change of plasma volume were calculated. Data analyses were performed by the SPSS v.16.

RESULTS

Out of 60 patients, 58.3% were male and 41.7% female. Post-dialysis systolic blood pressure (SBP) and diastolic blood pressure (DBP) were significantly lower than pre-dialysis values in both groups (P=0.001, each). No correlation was found between intradialytic change in plasma volume or body weight and alterations of SBP or DBP during HD in the study groups (P>0.05, each). Intradialytic changes of body weight did not correlate to intradialytic changes of plasma volume (P=0.15).

CONCLUSION

HD effectively reduces blood pressure and volume expansion, however, intradialytic changes of plasma volume and body weight do not influence on SBP and DBP.

Alcohol consumption and body weight

The number of Americans who are overweight or obese has reached epidemic proportions. Elevated weight is associated with health problems and increased medical expenditures. This paper analyzes Waves 1 and 2 of the National Epidemiological Survey of Alcohol and Related Conditions to investigate the role of alcohol consumption in weight gain. Alcohol is not only an addictive substance but also a high-calorie beverage that can interfere with metabolic function and cognitive processes. Because men and women differ in the type and amount of alcohol they consume, in the biological effects they experience as a result of alcohol consumption, and in the consequences they face as a result of obesity, we expect our results to differ by gender. We use first-difference models of body mass index (BMI) and alcohol consumption (frequency and intensity) to control for time-invariant unobservable factors that may influence changes in both alcohol use and weight status. Increasing frequency and intensity of alcohol use is associated with statistically significant yet quantitatively small weight gain for men but not for women. Moreover, the first-difference results are much smaller in magnitude and sometimes different in sign compared with the benchmark pooled cross-sectional estimates.

The role of lipid and carbohydrate digestive enzyme inhibitors in the management of obesity: a review of current and emerging therapeutic agents

Obesity is a global epidemic associated with significant morbidity and mortality in adults and ill health in children. A proven successful approach in weight management has been the disruption of nutrient digestion, with orlistat having been used to treat obesity for the last 10 years. Although orlistat-induced weight loss remains modest, it produces meaningful reductions in risk factors for obesity-related conditions such as diabetes and cardiovascular disease. Moreover, this lipase inhibitor is free of the serious side effects that have dogged appetite-suppressing drugs. This success had driven investigation into new generation nutraceuticals, supplements and pharmaceutical agents that inhibit the breakdown of complex carbohydrates and fats within the gut. This review focuses on agents purported to inhibit intestinal enzymes responsible for macronutrient digestion. Except for some synthetic products, the majority of agents reviewed are either botanical extracts or bacterial products. Currently, carbohydrate digestion inhibitors are under development to improve glycemic control and these may also induce some weight loss. However, colonic fermentation induced side effects, such as excess gas production, remain an issue for these compounds. The α-glucosidase inhibitor acarbose, and the α-amylase inhibitor phaseolamine, have been used in humans with some promising results relating to weight loss. Nonetheless, few of these agents have made it into clinical studies and without any clinical proof of concept or proven efficacy it is unlikely any will enter the market soon.

Effects of corn gluten hydrolyzates, branched chain amino acids, and leucine on body weight reduction in obese rats induced by a high fat diet

In this study, we compared corn gluten hydrolyzates, BCAAs, and leucine for their effects on body weight reduction in high fat-induced obese rats in order to determine the major active components in the corn gluten hydrolyzates. After obesity was induced for 13 weeks with high fat diet, the overweight-induced SD rats (n = 64) were stratified according to body weight, randomly blocked into eight treatments, and raised for 8 weeks. Four groups were changed to a normal diet and the other groups remained on the high fat diet. Each of the groups within both diets was fed either casein, corn gluten hydrolyzates, leucine, or branched chain amino acids, respectively. Daily food intake, body weight gain, and food efficiency ratio were significantly lower in the corn gluten hydrolyzate groups compared to the other groups, regardless of the high fat diet or normal fat diet. The rats fed the corn gluten hydrolyzates diet had the lowest perirenal fat pad weights whereas muscle weight was significantly increased in the corn gluten hydrolyzates groups. Plasma triglyceride, hepatic total lipid, and total cholesterol contents were significantly reduced in the corn gluten hydrolyzates groups. Other lipid profile measurements were not significantly changed. Plasma triglyceride and hepatic total lipid were also significantly reduced in the BCAA and leucine groups. Leptin levels were significantly lower and adiponectin was significantly higher in the corn gluten hydrolyzates groups. Fasting blood glucose, insulin, C-peptide, and HOMA-IR levels were also significantly reduced in the corn gluten hydrozylates groups, regardless of fat level.