Showing papers in "International Journal of Obesity in 1996"

The regulation of adipose tissue distribution in humans.

Abstract: The regulation of adipose tissue distribution is an important problem in view of the close epidemiological and metabolic associations between centralized fat accumulation and disease. With visceral fat accumulation multiple endocrine perturbations are found, including elevated cortisol and androgens in women, as well as low growth hormone (GH) and, in men, testosterone (T) secretion. These abnormalities probably derive from a hypersensitive hypothalamo-pituitary-adrenal axis, with hyperinsulinemia related to a marked insulin resistance as a consequence. These hormonal changes exert profound effects on adipose tissue metabolism and distribution. At the adipocyte level cortisol and insulin promote lipid accumulation by expressing lipoprotein lipase activity, while T, GH and probably estrogens exert opposite effects. The consequences will most likely be more expressed in visceral than subcutaneous adipose tissues because of a higher cellularity, innervation and blood flow. Furthermore, the density of cortisol and androgen receptors seems to be higher in this than other adipose tissue regions. The endocrine perturbations found in visceral obesity with an abundance of the lipid accumulating hormones cortisol and insulin, and a relatively low secretion of the lipid mobilizing sex steroid hormones and GH would therefore be expected to be followed by visceral fat accumulation. The potential significance of local synthesis of steroid hormones in adipose tissue requires more attention. Although studies in vitro are informative when elucidating detailed mechanisms of hormonal interactions, they might not give a true picture of the regional integrated regulation of adipose tissue lipid storage and mobilization. Such information can be obtained by regional measurements of lipid mobilization by free fatty acid turnover or by microdialysis techniques, both showing lower rates of mobilization in leg than in upper body adipose tissues. More detailed information can be obtained by physiological oral administration of triglycerides, labelled with a small amount of oleic acid, followed by measurements of the regional uptake and turn-over of adipose tissue triglycerides. Such studies show lipid uptake in the order omental = retroperitoneal > subcutaneous abdominal > subcutaneous femoral adipose tissues in men, with a similar rank order for half-life of the triglyceride, indicating also a turn-over of triglycerides in that order. T amplifies these differences in men. In premenopausal women subcutaneous abdominal has a higher turnover than femoral adipose tissue. Results of studies in vitro indicate that this difference is diminished at the menopause, and restored by estrogen substitution, suggesting that the functional effects of estrogens in women are similar to those of T in men. The mechanisms are, however, probably indirect because of the apparent absence of specific estrogen and progesterone receptors in human adipose tissue. This interpretation from the studies referred to above fits well with physiological, and clinical conditions with increased visceral fat mass, where the balance between the lipid accumulating hormone couple (cortisol and insulin) and the hormones which prevent lipid accumulation and instead activate lipid mobilization pathways (sex steroid hormones and GH) is shifted to the advantage of the former. Such conditions include Cushing's syndrome, the polycystic ovary syndrome, menopause, aging, GH-deficiency, depression, smoking and excess alcohol intake. With appropriate interventions against hypercortisolemia and substitution of deficient sex steroids and GH, visceral fat mass is decreasing. Based on this evidence from physiological, clinical, interventional observations and detailed studies of mechanisms at cellular and molecular levels it is suggested that the combined endocrine abnormalities in the syndrome of visceral obesity direct storage fat to visceral adipose depots. Therefore, measurements of visceral fat accumulat

The relationship between body weight and mortality : a quantitative analysis of combined information from existing studies

Abstract: OBJECTIVE : To estimate the relationship between body mass index (BMI, kg/m 2 ) and all-cause mortality with information from the published scientific literature. DESIGN : Meta-analysis using a hierarchical, mixed model. The analysis included random effects for information sources and fixed effects for factors that may modify the BMI-mortality relationship such as smoking, control for disease, and country of origin, which allowed combining information from diverse studies. MAIN OUTCOME MEASURES : Predicted probability of death over a given duration of follow-up plotted by BMI for sex-age cohorts of white race. RESULTS : An extensive search identified nineteen prospective cohort studies that met inclusion criteria. A U-shaped relationship between BMI and mortality was demonstrated for 50-year-old men followed for 30 years. Mortality risk increased with low and high BMI ( 28) in groups of non-smokers without evidence of disease upon study entry. Limited information from studies of women indicated that, with 10 year follow-up, there was little relationship between BMI and mortality for (1) non-smokers and for (2) mixtures of smokers and non-smokers. CONCLUSION : This quantitative analysis of existing studies revealed increased mortality at moderately low BMI for white men comparable to that observed at extreme overweight, which does not appear to be due to smoking or existing disease. Attention to the health risks of underweight is needed, and body weight recommendations for optimum longevity need to be considered in light of these risks.

The heritability of body mass index among an international sample of monozygotic twins reared apart.

Abstract: BACKGROUND : Published heritability estimates (h 2 ) for body mass index (BMI) range from as low as 0.05 to as high as 0.90. The purpose of this paper is to introduce new data to help narrow the range of plausible estimates. SUBJECTS : Subjects were 53 pairs (23 M ; 30 F) of monozygotic twins reared apart (MZAs), whose mean BMI was 24.2 (SD = 4.7). BMI's were transformed to approximate normality via the Box-Cox transformation. Twin pairs came from the Finnish Twin Cohort (17 pairs), a data base of Japanese twins (10 pairs) and published case histories of primarily American twins (26 pairs). RESULTS : The h 2 for MZAs is given by the correlation among the twin pairs. For the transformed data, the zero-order correlation of twins' BMIs was 0.79 for all twins, 0.63 for the Finnish twins, 0.73 for the Japanese twins and 0.85 for the 'archival' twins. When modeled with regression to control for relevant covariates, the estimate of h 2 is either 0.50 or 0.70. depending on one's definition. The semipartial r was 0.50, suggesting that 50% of the total variance in BMI appears to the genetic in origin after controlling the covariates. The partial r was 0.70, suggesting that 70% of the variance in BMI that is not accounted for by the covariates can be attributed to genetic variation. Separation age had a small positive correlation with absolute intra-pair difference in BMI, suggesting that these estimates of h 2 are not biased upwards due to early shared environment. CONCLUSIONS : Findings are consistent with past studies of MZAs and suggest that h 2 estimates between 0.50 and 0.70 are reasonable. Implications of this finding are discussed.

Obesity as a protective factor for postmenopausal osteoporosis.

Abstract: BACKGROUND : Obesity is considered a protective factor for osteoporosis improving bone mass and maintaining higher levels of estrogen during menopause. OBJECTIVE : To determine the association of obesity with bone mineral density (BMD), and its relationship with sex hormone levels. DESIGN : A case-control study in Caucasian obese and non obese postmenopausal women. SUBJECTS : 113 obese and 50 non-obese postmenopausal women. MEASUREMENTS : BMD (dual-photon X-ray absorptiometry) at cervical femur. Ward's triangle, proximal radius and lumbar spine. Plasma levels of glucose, insulin, total estrogen, follicle stimulating hormone (FSH), sex hormone binding globulin (SHBG), dehydroepiandrosterone sulfate (DHA-S) and testosterone. RESULTS : Mean BMD at femoral sites were significantly higher in obese women (femoral neck : 0.849 ± 0.124 g/cm 2 vs 0.753 ± 0.095 g/cm 2 , P < 0.001 ; Ward's triangle : 0.634 ± 0.134 g/cm 2 vs. 0.553 ± 0.100 g/cm 2 , P < 0.001). Mean BMD at lumbar spine was 0.906 ± 0.138 g/cm 2 in obese women and 0.849 ± 0.137 g/cm 2 in non obese, P < 0.017. A decreased risk of osteopenia in femoral neck (Age adjusted OR = 0.36, 95% CI 0.17-0.75) and in lumbar spine (Age adjusted OR = 0.43, 95%CI 0.20-0.91) in obese women was observed. Although total estrogen were similar in both groups, in obese women, SHBG was lower (68.6 ± 26.84 nmol/l vs. 85.1 ± 31.18 nmol/l, P < 0.001), and postglucose load insulin levels were higher, than in non obese (77.2 ± 50.4 Ul/ml vs. 49.4 ± 24.1 Ul/ml, P< 0.0005). CONCLUSION : The findings confirm a higher BMD in obese women and suggest that obesity exerts protection due to a decreased SHBG thus increasing free sex steroids. Besides, hyperinsulinemia may produce a decline in the production of IGFBG-1, leading to an increase of IGF-1, that may stimulate the proliferation of osteoblasts.

Overweight, gender and knee osteoarthritis.

Abstract: A 10-year follow-up study was carried out among 6647 farmers aged 40-64 y to investigate associations between age, gender, body mass index (weight/height 2 ) and the incidence of disabling knee osteoarthritis. After the follow-up (1980-1990) a record linkage with the Social Insurance Institution's register was made to identify disability pensions. All the medical certificates for the disability pensions (N = 965) were reviewed to find out the incident cases (N = 126). Age, female gender and body mass index were all independent predictors of disabling knee osteoarthritis. The relationship between body mass index and the incidence of disabling knee osteoarthritis was linear, the adjusted relative risk was 1.4 (95% CI, 1.2-1.5) per standard deviation of the index (3.8 kg/m 2 ). In women, as compared with men, the adjusted relative risks (95% confidence intervals) of right unilateral, left unilateral and bilateral knee osteoarthritis were 7.0 (2.5-19.7), 3.3 (1.1-9.8) and 4.8 (2.4-9.3), respectively. Overweight is a strong risk factor for disabling knee osteoarthritis.

Family-based behavioural intervention for obese children.

Abstract: The family environment can contribute to the development of obesity. Parenting styles may influence the development of food preferences and the ability of a child to regulate intake. Parents and other family members arrange a common, shared environment that may be conducive to overeating or a sedentary lifestyle. Family members serve as models, and reinforce and support the acquisition and maintenance of eating and exercise behaviours. Family-based interventions are needed to modify these variables in treating obese children. We have made significant progress in developing interventions that target obese 8-12 year-old children, completing four 10-year follow-up studies that provide support for two factors that are useful in childhood obesity treatment. First, our research suggests that the direct involvement of at least one parent as an active participant in the weight loss process improves short- and long-term weight regulation. Second, our research suggests that increasing activity is important for maintenance of long-term weight control. Correlational analyses on the 10-year database suggest that family and friend support for behaviour change are related to long-term outcome. Family-based obesity treatment provides interventions for both children and their parents, but children benefit more from treatment than their parents. These positive results provide an encouraging basis for optimism that further development of interventions, based on newer research on family processes and behaviour changes, can be useful in treating childhood obesity.

Relationship of uric acid concentration to cardiovascular risk factors in young men. Role of obesity and central fat distribution. The Verona Young Men Atherosclerosis Risk Factors Study

Abstract: OBJECTIVE: To examine the relationships of serum uric acid concentration with several risk factors of cardiovascular diseases (CVD). SUBJECTS: 957 men 18 y old participating in the Verona Young Men Atherosclerosis Risk Factors Study, a cross-sectional population-based study. MEASUREMENTS: Body mass index (BMI), waist/hip ratio (WHR), serum uric acid, serum lipids, blood pressure, fasting insulin and behavioural variables. RESULTS: Serum uric acid concentration showed positive associations with BMI (r = 0.24; P < 0.0001), WHR (r = 0.19; P < 0.0001) and serum triglyceride levels (r = 0.19; P < 0.0001); it was also significantly correlated to systolic (r = 0.08; P < 0.01) and diastolic (r = 0.11; P < 0.001) blood pressure, fasting insulin (r = 0.11; P < 0.001), total (r = 0.12; P < 0.001) and LDL cholesterol (r = 0.10; P < 0.01) plasma concentrations. Life-style characteristics, such as smoking and physical activity did not show any significant association, while daily alcohol intake was positively associated with uric acid concentration (r = 0.09; P < 0.01). While the adjustment for fasting insulin did not substantially change these results, the magnitude of the correlations between uric acid and CVD risk factors markedly decreased when allowance was made for BMI and WHR. Only triglycerides maintained an independent correlation with uric acid levels (r = 0.17; P < 0.0001). In multivariate regression analysis, serum triglycerides, BMI and WHR (at borderline significance) were independent positive predictors of uric acid (R2 of the model 0.122, P < 0.001), while fasting insulin concentration did not give any independent contribution to explain the variability uric acid levels. CONCLUSIONS: These data indicate that, already in young, essentially health subjects, hyperuricaemia associates with several components of the so-called insulin resistance syndrome, thus suggesting that increased levels of uric acid might be another member of this syndrome. In addition, these data suggest that obesity and central body fat distribution, rather than hyperinsulinaemia/insulin resistance, play a major role in linking hyperuricaemia with CVD risk factors clustering in the insulin resistance syndrome. Nevertheless, hypertrigliceridemia is related to hyperuricemia independently of obesity and central body fat distribution.

Food provision vs structured meal plans in the behavioral treatment of obesity.

Abstract: OBJECTIVE : Providing overweight patients with the food they should eat has been shown to significantly improve weight loss in a behavioral treatment program. The objective of this study was to examine the contribution of three components of food provision to these positive effects : the specific meal plans indicating what foods should be eaten at each meal ; the food itself ; and the fact that the food was provided free. SUBJECTS : 163 overweight women. DESIGN : Randomized, controlled study with subjects assigned to one of four conditions : (1) a standard behavioral treatment program (SBT) with weekly meetings for six months ; (2) SBT plus structured meal plans and grocery lists ; (3) SBT plus meal plans plus food provision, with subjects sharing the cost ; or (4) SBT plus meal plans plus free food provision. RESULTS : Subjects in Group 1 lost significantly less weight than subjects in Groups 2-4 at the end of the six month program (-8.0 kg vs -12.0, -11.7 and -11.4 kg respectively) and at follow-up one year later (-3.3 kg vs -6.9, -7.5 and -6.6 kg respectively). No significant differences were seen in weight loss between Groups 2-4, suggesting that the component of food provision that is responsible for its success is the provision of highly structured meal plans and grocery lists. Subjects receiving meal plans were more likely to exhibit an eating pattern of three meals/day, had more definite plans regarding what to eat and reported more favorable changes in foods stored in their homes and in perceived barriers to weight loss. CONCLUSIONS : Providing structured meal plans and grocery lists improves outcome in a behavioral weight control program ; no further benefit is seen by actually giving food to patients.

Binge-eating disorder and the night-eating syndrome.

Abstract: OBJECTIVE : To determine in three samples of obese women the prevalence of two eating disorders - binge eating disorder and the night-eating syndrome. METHOD : Interviews utilizing standard criteria. For binge eating disorder : the consumption of large amounts of food in a discrete period of time together with a subjective sense of loss of control and no vomiting or laxative abuse. For the night-eating syndrome : morning anorexia, evening hyperphagia and insomnia. Determining the rate of binging among patients receiving a placebo. SUBJECTS : (1) 102 viewers of a television show describing binge eating disorder ; (2) 50 participants in a trial of medication for this disorder and (3) 79 participants in a weight reduction program. RESULTS : In the television sample 19.6% of respondents and in the weight reduction sample 7.6% met criteria for binge eating disorder ; all subjects in the medication sample met criteria. During a 4-week placebo period average binge frequency fell from 6.0 to 1.7 binges per week. The night-eating syndrome was manifested by 13.7% of the television sample, 8.9% of the weight reduction sample and 15.0% in the medication trial sample. There was little overlap between the two disorders. CONCLUSIONS : Binge eating disorder is far less frequent than has been believed on the basis of questionnaire studies and it is highly responsive to placebos. Frequency of the night-eating syndrome is comparable to that of binge eating disorder. Future studies should assess binge eating disorder by interview rather than by self-administered questionnaire.

Additive effect of A-->G (-3826) variant of the uncoupling protein gene and the Trp64Arg mutation of the beta 3-adrenergic receptor gene on weight gain in morbid obesity

Abstract: OBJECTIVE: Obesity results from an imbalance between caloric intake and energy expenditure, which is partly genetically determined. We have investigated, using a PCR-RFLP assay, the effects on weight gain of two genetic variants of the uncoupling proteins and the beta 3-adrenoceptor, two major expressed proteins of the brown adipose tissue (BAT) involved in thermo-genesis. SUBJECTS: 238 morbidly obese and 91 non obese Caucasian subjects. RESULTS: A high prevalence (27%) in French Caucasians of the A-->G change variation located in the 5' flanking domain of the UCP gene was observed with no significant difference between morbidly obese patients and non obese subjects, suggesting that UCP gene is not a major gene for obesity. However, in the population of morbidly obese subjects, the presence of the A-->G allelic variant of the UCP gene showed to be an associated factor of high weight gain during adult life (odd-ratio: 1.4, P = 0.02). Such an association was previously described for the Trp64Arg mutation of the beta 3-AR gene. Furthermore, an additive effect of these two gene variants on weight gain was observed (Odd-Ratio: 4.95, trend test: P = 0.05). The attributable risks for UCP gene and beta 3-AR gene variants were respectively: 25% and 9%. CONCLUSION: These data support the hypothesis of a possible link between energy balance, BAT and weight gain in human.

Leptin is cleared from the circulation primarily by the kidney

Abstract: OBJECTIVE : This study was performed to determine the pharmakocinetics of recombinant leptin in lean rats and to test the hypothesis that the kidneys play an important role in the clearance of leptin from the circulation. DESIGN : 125 I-leptin was administered by bolus intravenous injection. Blood samples were taken at various time points ranging from 1-180 min after administration and assayed for leptin. Pharmacokinetic parameters were determined in normal animals and after either bilateral nephrectomy or bilateral ureteral ligation. RESULTS : Leptin was eliminated from the circulation following a three compartment model. The importance of the kidneys to the systemic clearance of leptin was studied by administrating leptin to binephrectomized rats. The systemic clearance of leptin in anephric rats was only 19% of that calculated for control animals. In order to assess the role of glomerular filtration, both ureters were ligated 5 h before leptin administration. Ureteral ligation reduced the systemic clearance of leptin by 30%. CONCLUSION : These findings demonstrate that the short half life of leptin in the circulation is mainly determined by efficient renal clearance which is mediated in part by glomerular filtration.

Defining obesity in children by biological endpoint rather than population distribution.

Abstract: OBJECTIVE : To investigate the association of fatness in children with dyslipoproteinemia and high blood pressure, with the purpose of proposing standards for childhood obesity which are directly related to intermediate biological parameters that predict future disease. DESIGN : A cross-sectional study of a large, nationally representative sample of Australian schoolchildren. SUBJECTS : 1834 children aged 9 or 15 years, with skinfolds blood lipid measurements on 1144 and with skinfolds and blood pressure measurements on 1757. MEASUREMENTS : Skinfolds thicknesses measured at four locations (triceps, biceps, subscapular and suprailiac) using holtain calipers, percent body fat calculated from the sum of four skinfolds, Quetelet's index calculated from weight and height, waist and hip circumferences, plasma total cholesterol and triglycerides determined using a Technicon Autoanalyser II, high density lipoprotein cholesterol (HDLC) analysed following precipitation with heparin manganese, and systolic blood pressure (SBP) measured using a standard mercury sphygmomanometer. RESULTS : For 9 years old girls, 15 year old girls and 9 year old boys, dichotomising their HDLC and SBP measurements by percent body fat defined the two groups most homogeneous in terms of a measure of within-group variation. The cut-points in percent body fat were in the ranges 29-35% (girls) and 17-20% (boys). CONCLUSION : It is feasible to use the current biomedical status of individual children to define criteria for obesity. A cut-off point of 30% body mass as fat for girls and 20% for boys appears to be an appropriate standard.

High prevalence of overweight and obesity in Saudi Arabia.

Abstract: OBJECTIVES : to study the pattern of body weight distribution and the prevalence of overweight and obesity in Saudi Arabia DESIGN : Cross-sectional national epidemiological household survey SUBJECT : 13177 Saudi subjects, over the age of 15 years The sample was adjusted for gender, age, regional and residency population distribution The range and mean of age was similar for male and female subjects (15-95 years, 33 years) MEASUREMENT : questionnaire, describing the social, educational and financial status Measurement of height, weight and calculation of body mass index (BMI) WHO classification was used for defining overweight (BMI 25-30) and obesity (BMI > 30) RESULTS : The mean BMI for female subjects was significantly higher than for male subjects, whether for all subjects or subjects of any given age group There was a progressive increase of BMI for male and female subjects with age, reaching maximum at the 5th decade The prevalence of overweight among male subjects was significantly higher than for female subjects (29% vs 27%) The prevalence of obesity among female subjects was significantly higher than for male subjects (24% vs 16%) There was a gender variation within each region with respect to the prevalence of overweight with higher prevalence of overweight among male subjects, throughout all the regions, except the Southern region, none of the differences, however, reached significance levels The prevalence of obesity was significantly higher among female subjects, throughout all the regions Overweight and obesity were more prevalent among illiterate, high-income subjects who were residing in urban communities CONCLUSION : This epidemiological household survey has shown high prevalence of overweight and obesity among Saudi subjects The prevalence of obesity among female Saudi subjects was among the highest reported, whether, when using the WHO criteria or the 85th percentile of US subject aged 20-29 years The increase of prevalence of such conditions among high income subjects would reflect the perception of fatness as sign of affluence among those subjects As the prevalence of obesity increases with age and considering that the majority of Saudi population are less then 30 years old at the present time, then, one would expect the magnitude of obesity to be even bigger in the near future There is a need to establish programs for promoting awareness among the population of the health hazards and means of control of obesity

The roles of tissue inhibitors of metalloproteinases in tissue remodelling and cell growth

Abstract: Tissue inhibitors of metalloproteinases (TIMPs) are secreted proteins that block the activities of the extracellular matrix (ECM)-degrading metalloproteinases (MMPs). As key determinants of ECM integrity and turnover, TIMPs are involved in the establishment and maintenance of tissue architecture and may indirectly influence ECM-dependent cells signaling. In addition, TIMPs exert both positive and negative effects on cell growth through mechanisms that are independent of MMP inhibition. The three members of the mammalian TIMP family differ in structure, biochemical properties and expression, suggesting that they have distinct physiological roles. Here, we review recent advances in our understanding of TIMP protein function and gene regulation. We discuss the potential relevance of MMPs and TIMPs in obesity with regard to effects on the processing of tumor necrosis factor-alpha.

Reproductive history in relation to relative weight and fat distribution

Abstract: Department of Primary Health Care, Sahlgrenska University Hospital, Goteborg University, Gothenburg, Sweden OBJECTIVE: To investigate the relationship between reproductive history and body composition DESIGN: Prospective population study in Sweden SUBJECTS: 1462 randomly selected women representing five separate age cohorts (38, 46, 50, 54 and 60 at the 1968-1969 baseline examination) have been followed longitudinally MEASUREMENTS: Relative weight, fat distribution, and fat cellularity were related to menarche, parity, lactation, menopause and oestrogen medication RESULTS: Age of menarche did not show any association with subsequent fat distribution, nor did length of lactation time On the other hand parity was positively associated to total as well as central obesity, and lactation time was positively associated to abdominal fat cell diameter Premenopausal women showed higher mean body weight and hip circumference than postmenopausal women of the same age Change from pre- to postmenopausal status was associated with increase of waist circumference as well as reduction of hip circumference, resulting in an increased waist-hip ratio (WHR) Oestrogen replacement suggested some postponement of this increase CONCLUSION: Parity and menopause are the reproductive factors most associated with gradual changes in body fat distribution Oestrogen medication seems to play an additional role in diminishing waist circumference increase and could thus contribute to decreased cardiovascular morbidity in women PMID: 8653141 [PubMed - indexed for MEDLINE]

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

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

The influence of occupational and social factors on obesity and body fat distribution in middle-aged men.

Abstract: OBJECTIVE : The principal aim of the present study was to analyse possible associations between psychosocial and occupational factors with body mass index (BMI) and the waist-to-hip circumference ratio (WHR). DESIGN : A cohort study of data derived from questionnaires. SUBJECTS : 1040 men from a population sample of 1302 men born 1944. MEASUREMENTS : Occupational, social and leisure time conditions, smoking and alcohol habits as well as height, weight and waist-to-hip circumferences. RESULTS : In multivariate analyses, the BMI, when adjusted for the WHR, smoking and alcohol, was marginally associated with shift work and, negatively, with influence on the work situation. Such men were often married or cohabited, had a low educational level, felt little time pressure and watched TV frequently. In contrast men with elevated WHR, when adjusted for BMI, alcohol and smoking, seemed to be more often out of work, and to be less satisfied with work management. They were frequently divorced and lived under relatively poorer housing conditions, indicating a low socio-economic status, exercised seldom and had little leisure time activities. CONCLUSION : It was concluded that obesity (BMI) and centralisation of body fat stores (WHR) are differently associated to occupational and social factors as well as leisure time activities.

Prevalence of overweight and weight gain in relation to night work in a nurses' cohort.

Abstract: OBJECTIVE : To investigate the relation between exposure to night work and prevalence of overweight and weight gain. DESIGN : Longitudinal observational study. SUBJECTS : 469 nurses (age : 21-58 y). MEASUREMENTS : Body Mass Index, exposure to night work, age, parity, smoking and sports activities in 1980, 1985 and 1990. RESULTS : Prevalence of overweight was associated with exposure to night work in 1980 and weight gains (especially those exceeding 7 kg) were more frequent among nurses on night work than on daytime work between 1985 and 1990. CONCLUSION : Exposure to night work can lead to weight gain and overweight.

Prospects for beta 3-adrenoceptor agonists in the treatment of obesity and diabetes.

Abstract: beta 3-Adrenoceptor (beta 3-AR) agonists were first identified more than twelve years ago and were found to be remarkably effective in animal models of obesity and Type II (non-insulin dependent) diabetes. Those that have been taken forward to clinical studies have not, however, proved so effective in humans: they have either been of limited efficacy, or their activities have been accompanied by significant side-effects. Reasons for the failure of some beta 3-AR agonists in humans have included a poor pharmacokinetic profile and, possibly, a failure of prodrugs to be metabolised to selective beta 3-AR agonists. A more fundamental problem, however, is that the human and rat beta 3-AR differ pharmacologically, and those compounds that have been evaluated in humans have much lower efficacy at the human than the rat receptor. This problem may be compounded by there being a low number of beta 3-AR relative to beta 1-AR and beta 2-AR in those tissues that mediated thermogenesis in humans, so that low efficacy compounds tend to exhibit mainly beta 1-AR or beta 2-AR-, rather than beta 3-AR-mediated effects, despite their having selective affinity for human beta 3-AR. Nevertheless, studies using CGP 12177, which is an agonist at beta 3-AR but an antagonist at beta 1-AR and beta 2-AR, demonstrate that functional beta 3-AR are present in human adipose tissue. Moreover, the association of a polymorphism in the human beta 3-AR with obesity and diabetes demonstrates that this receptor is relevant to these diseases in humans. Thus the true potential of beta 3-AR agonists in humans can only be evaluated when a compound with good selectivity and efficacy at the human beta 3-AR, coupled with a long duration of action in vivo, has been identified.

Economic consequences of sick-leave and early retirement in obese Swedish women

Abstract: OBJECTIVES : To describe the pattern of sick-leave and disability pension in an obese sample and to estimate the incremental, indirect cost due to sick-leave and early retirement for the obese fraction of the Swedish female population. DESIGN : A retrospective study of sick-leave and disability pension in health examined obese subjects was performed. The indirect cost of obesity in Sweden was estimated from reported and recorded sick-leave and disability pension in the sample and from the estimated prevalence of obesity in the country. SUBJECTS : 1298 obese persons aged 30-59 y. The mean age was 46 years. The mean body mass index was 39 kg/m 2 (range 28-68). SETTING : The obese subjects were recruited from eight counties in Sweden. RESULTS : As compared to the general Swedish population the obese subjects had 1.5-1.9 times higher sick-leave during one year. Twelve percent of the obese women had disability pension while the corresponding figure in the general population was 5%. The incremental cost of sick-leave and disability pensions attributable to obesity was 3.6 billion SEK during one year, which is equivalent to about 300 million USD per million female adult population. The total cost for sick-leave and disability pension due to absence from work for the obese fraction of the Swedish female population was 10.5 billion SEK during one year. CONCLUSION : Obesity represents a major health problem with significant economic implications for the society. Approximately 10 percent of the total cost of loss of productivity due to sick-leave and disability pensions in women may be related to obesity and obesity-related diseases.

The pattern of growth and obesity in Saudi Arabian male school children.

Abstract: OBJECTIVE : To determine the prevalence of overweight and obesity among male school children in Saudi Arabia and provide a growth chart for males 6-18y old. DESIGN : Three stage stratified cluster sampling procedure. SUBJECTS : The study population was 9061 male school children, attending public schools in Saudi Arabia. Their ages ranged from 6-18y and covered all the 12 grade levels of school. Children with evidence of chronic or acute diseases were excluded from the study. MEASUREMENT : Structured questionnaire, including : location of school, socio-demographic characteristics and age of the student. Anthropometric measurements of weight and height was done for all the study sample. Growth charts were designed through fitting the polynomial regression model of degree three. The percentage of body mass index (BMI) of expected BMI at the 50th percentile for each age group was computed. The 50th percentile of The National Center for Health Statistics/Center for Disease Control reference population was used as the expected standard population values for defining childhood overweight and obesity. RESULTS : The overall prevalence of overweight was 11.7% and obesity 15.8%. There was a statistically significant variation in the regional distribution of overweight and obesity (P<0.01). The highest prevalence (18.0%) was recorded in Riyadh, capital of Saudi Arabia, and the lowest was in Sabea (11.1%) located in the Southern region. CONCLUSION : These findings of a high prevalence of childhood obesity when compared with the NCHS/CDC calls for an early health education program on the appropriate choice of diets for growth, health and longevity. However, because of the possible ethnic differences between the Saudi and American populations, the growth charts presented could serve as a better reference for future comparisons.

Clinical characteristics associated with binge eating in obese females: a descriptive study.

Abstract: OBJECTIVE : To investigate differences in clinical characteristics of obese female participants based on presence and degree of binge eating behavior. DESIGN : Descriptive comparison of various clinical characteristics of obese women diagnosed with binge eating disorder (BED) assessed by semi-structured interview to those for similar weight participants reporting subthreshold BED and those who do not binge eat. SUBJECTS : 185 healthy women seeking obesity treatment (age : 20-55 y, BMI : 28.4-51.5 kg/m 2 ). MEASUREMENTS : Baseline self-report questionnaires included the Weight and Eating Patterns (QEWP). Eating Disorders Questionnaire (EDQ), Beck Depression Inventory (BDI) ; clinical interviews included the Hamilton Depression Rating Scale (HDRS) and Structured Clinical Interview for DSM-III-R-Patient Version (SCID-P). RESULTS : In comparison to other obese women, obese participants meeting full BED criteria report an earlier onset of binge eating, increased food cravings, increased diet pill use, decreased fasting, greater fear of gaining weight, increased body perception disturbance, and increased depressive symptomatology and general psychopathology. CONCLUSIONS : Obese women with BED report greater eating-related and general psychopathology than non-binge eating disordered women of comparable weight. Although endorsement of food cravings unrelated to hunger was associated with binge eating diagnosis, the role of dietary restriction among this population remains unclear and requires further investigation. Theoretical and clinical implications that binge eating episodes for individuals with BED may be related to negative affect states and increased dietary disinhibition are discussed.

Anthropometric correlates to changes in visceral adipose tissue over 7 years in women

Abstract: OBJECTIVE : To investigate the association between either increases or decreases in visceral adipose tissue and changes in anthropometric indices in a group of 32 women studied over a 7-y period. SUBJECTS : 32 women aged 35.1 ± 5.4 (SD) years at baseline. MEASUREMENTS : Waist and hip circumferences. body fat mass (hydrostatic weighing) and visceral adipose tissue (computed tomography) were measured at baseline and at follow-up. RESULTS : Waist girth, waist-to-hip ratio, sagittal diameter and visceral adipose tissue area were all significantly higher at follow-up than at baseline (p < 0.05). Changes in visceral adipose tissue area were strongly correlated to changes in waist girth, hip girth, sagittal diameter and body fat mass (0.80 ≤ r ≤ 0.91 ; p < 0.0001). However, the association between changes in waist-to-hip ratio and those in visceral adipose tissue area was of low magnitude (r = 0.35 ; p = 0.05). Partial correlation analyses showed that the association between changes in visceral adipose tissue area and changes in either waist girth (p < 0.01) or sagittal diameter (p < 0.0001) remained significant even after control for 7-y variation in total body fatness. CONCLUSION : Results of the present study suggest that changes in visceral adipose tissue accumulation that occur with age in women are better predicted by changes in waist girth or sagittal diameter than by changes in waist-to-hip ratio.

Trends in body mass index and obesity among adults in Finland from 1972 to 1992.

Abstract: OBJECTIVE : To investigate trends in body mass index (BMI) and prevalence of obesity in different areas and educational groups in Finland. DESIGN : Cardiovascular risk factor surveys carried out at five-year intervals among men and women aged 30 to 59 years from 1972 to 1992. MEASUREMENTS : Body mass index and educational level have been measured in each survey. RESULTS : BMI increased in men over 40 years of age until 1987 and then levelled off. BMI decreased in women in all age groups until 1982 and then levelled off. Even though all men have become heavier, the change has been smallest in the highest educated group. This difference is even more pronounced in women. The prevalence of obesity (BMI over 30 kg 2 ) was 19% in men and 18% in women in 1992. The prevalence of overweight (BMI over 25 kg/m 2 ) was 63% in men and 49% in women. The prevalence of obesity among men with the lowest educational level was 27% and in women 26%. CONCLUSION : The differences in BMI between educational groups have become wider in both genders during 1972-1992.

Autoregulation of body composition during weight recovery in human : the Minnesota experiment revisited

Abstract: Objectives To gain insights into the control systems underlying human variability in the regulation of body composition during weight recovery, as well as the disproportionate recovery of fat relative to lean tissue, the classical Minnesota Experiment conducted on 32 men subjected to long-term semi-starvation and refeeding was revisited with the following objectives: (1) to determine whether the control of energy-partitioning between lean and fat tissues during weight loss and weight recovery is an individual characteristic, and if a predictor can be statistically identified, (2) to determine whether the reduction in thermogenesis during weight loss persists during weight recovery, and underlies the disproportionate recovery of fat tissue and (3) to integrate the control of energy-partitioning and that of thermogenesis in order to explain the pattern of lean and fat tissue mobilisation and deposition during weight loss and weight recovery. Methods Individual data on body weight, body fat, fat-free-mass (FFM), and basal metabolic rate (BMR), assessed during the control baseline period (i.e. prior to weight loss), at the end of 24 weeks of semi-starvation, and at the end of a 12 week period of restricted refeeding, were used to calculate the following parameters: (i) a quantitative index of energy-partitioning, the P-ratio, defined as the proportion of body energy mobilised as protein during weight loss, or as the proportion of body energy deposited as protein during weight recovery, (ii) a quantitative index of changes in thermogenesis, defined as the change in BMR adjusted for FFM (or for both FFM and fat mass) and (iii) the degree of replenishment of fat and FFM compartments, defined as the recovery of body fat and FFM (during refeeding) as a percentage of that lost during semi-starvation. Results This re-analysis indicates the following: (i) a large inter-individual variability in P-ratio during both weight loss and weight recovery, but for a given individual, the P-ratio during refeeding is strongly correlated with the P-ratio during semi-starvation, (ii) body composition during the control period is the most important predictor of variability in P-ratio, such that the higher the initial % body fat, the lower the proportion of energy mobilised as protein, and hence the greater the propensity to mobilise fat during semi-starvation and to subsequently deposit fat during refeeding and (iii) at week 12 of refeeding, the change in adjusted BMR is found to be reduced by a magnitude which is inversely proportional to the degree of fat recovery, but is unrelated to the degree of FFM recovery. A quantitative relationship is derived between the P-ratio during refeeding, the % fat recovery, and the P-ratio during semi-starvation. Conclusions Evidence is presented here suggesting that (i) human variability in the pattern of lean and fat tissue deposition during weight recovery is to a large extent determined by individual variations in the control of energy-partitioning, for which the initial % body fat is the most important predictor and (ii) the disproportionate gain in fat relative to lean tissue during weight recovery is contributed by a reduction in thermogenesis (i.e. increased efficiency of food utilization) for accelerating specifically the replenishment of the fat stores. These control systems, operating via energy-partitioning and thermogenesis, have been integrated into a compartmental model for the regulation of body composition during underfeeding/refeeding, and can be used to explain the individual pattern of lean and fat tissue deposition during weight recovery in situations ranging from the rehabilitation after malnutrition to the relapse of obesity.

Leptin concentrations in relation to overall adiposity and regional body fat distribution in Mexican Americans.

Abstract: OBJECTIVE Leptin, the product of the human OB gene is increased in obese individuals suggesting resistance to its effect. However, there is variability in leptin levels at each level of body mass index suggesting that genetic and environmental factors other than overall adiposity may regulate leptin concentrations. Moreover, the relation of leptin to various adipose depots may differ. Upper body (or central adiposity) is more metabolically active than peripheral adiposity. METHODS We examined the relation of serum leptin levels to body fat distribution in 147 non-diabetic subjects from the San Antonio Heart Study. RESULTS Leptin concentrations in men were significantly correlated with body mass index (BMI) (r = 0.741), waist-to-hip ratio (WHR) (r = 0.567), waist circumference (r = 0.840), hips circumference (r = 0.842) triceps skinfold (r = 0.520) and subscapular skinfold (r = 0.668) but not with subscapular to triceps skinfold (r = 0.185). Leptin concentrations in women were significantly correlated with BMI (r = 0.814), WHR (r = 0.377), waist circumference (r = 0.718), hips circumference (r = 0.779), subscapular skinfolds (r = 0.636) and triceps skinfolds (r = 0.587) but not with the ratio of subscapular to triceps skinfolds (r = 0.184) in women. CONCLUSIONS Since the associations of leptin with body mass index (a surrogate for overall adiposity), waist circumference (a surrogate for upper body) and hips circumference (a surrogate for lower body adiposity) are similar, we conclude that leptin concentrations are associated with all adipose tissue depots and not disproportionately with upper body or central adiposity.

Binge eating in obesity

Abstract: Objective To investigate the influence of dieting and of body shape dissatisfaction on binge eating. Design Longitudinal study following billiopancreatic diversion (BPD), when the body shape has become normal or nearly normal, and any worries over weight, dieting and food have probably been abandoned completely. Subjects 65 severely obese patients, evaluated by clinical semistructured interview for occurrence of binge eating episodes prior to, and at one and at two years following BPD. Results Whereas preoperative binge eating had been reported by 65% of the obese individuals, at two years following BPD binge eating occurred only in 9.2% of them. Conclusions Weight stabilisation following BPD is associated with a sharp improvement in control over food intake, and this suggests the central role of dieting and/or of body dissatisfaction in causing binge eating episodes.

Microalbuminuria in obese patients with or without hypertension.

Abstract: OBJECTIVE : To evaluate the prevalence in obese patients of an increased urinary albumin excretion rate (UAER) and the factors involved in this parameter. SUBJECTS : Two hundred and seven nondiabetic obese patients with BMI = 34.7 ± 5.7 (SD) kg/m 2 . None had proteinuria or a history of nephropathy or uropathy. Fifty-two had moderate hypertension. A control group of 22 lean healthy subjects was also studied. MEASUREMENTS : The UAER was determined from 24-h urine samples by means of a immunonephelemetry laser method. Creatinine clearance was calculated. Glycemia and plasma C peptide at fasting and 120 min after glucose oral administration, HbA1c, serum fructosamine, plasma total cholesterol and triglycerides, HDL and LDL cholesterol were measured. Food intakes were determined by dietary history. RESULTS : Compared with the control group, the UAER was significantly higher in the obese patients (18.0 ± 20.1 mg/24 h vs 3.2 ± 2.8 mg/24 h, p 30 mg/24 h) in 25 obese patients (12.1%) and in particular, in 19.2% of the obese patients with hypertension. It was significantly higher in the patients with android or mixed (both android and gynoid) obesity than in those with gynoid obesity (p = 0.050). Log UAER correlated negatively with the duration of hypertension (p = 0.038) and was higher in the patients with familial hypertension than in those without (p = 0.002). Log UAER correlated strongly with log creatinine clearance (p < 0.0001) and fractional albumin clearance (p < 0.0001). It correlated significantly with fasting and 120 min after glucose plasma C peptide concentrations (p = 0.018 and p = 0.046, respectively). Creatinine clearance was significantly higher in the patients with android or mixed obesity than in those with gynoid obesity (p=0.001). Log creatinine clearance correlated negatively with age (p = 0.046), and log LDL cholesterol (p = 0.025) and positively with log lipid caloric intake (p = 0.014). CONCLUSION : These results show the high prevalence of microalbuminuria in nondiabetic obese patients and suggest the involvement of renal hyperfiltration. Microalbuminuria may be an indicator of familial hypertension in obese subjects. Insulin resistance may be involved in the increase in the UAER. Nutritional factors, particularly lipid intake, may contribute to this increase in the UAER via an increase in glomerular hyperfiltration.

Intra-abdominal adipose tissue cut-points related to elevated cardiovascular risk in women

Abstract: Intra-abdominal adipose tissue (IAF) seems to be the primary fat depot putting individuals at risk for cardiovascular disease (CVD) The purpose of this study was to determine IAF cut-points for identifying CVD risk in pre- and post-menopausal women Age ranged from 18 to 77 y and percentage fat ranged from 9 to 48% Computed tomography (CT), IAF, DEXA determined regional fat and blood lipid profiles were obtained on 220 Caucasian women Student's t-tests were run to determine differences between pre-and post-menopausal women Receiver-operating characteristic (ROC) analysis was used to develop IAF cut-points associated with elevated CVD risk Post-menopausal women had higher percentage fat, greater proportion IAF and higher CVD risk Menopausal status was not consistently independently related to CVD risk after adjusting for IAF, but IAF was after adjusting for menopausal status The same cut-points for CVD risk were found with both 4- and 6-CVD risk factor analysis and for both pre- and post-menopausal as well as pooled data 4-CVD risk factor analysis comprised cholesterol (C), HDL-C, systolic blood pressure and diastolic blood pressure 6-CVD risk factor analysis comprised the 4-CVD risk factors plus triglycerides and cholesterol : HDL-C ratio ROC L positive values indicate levels of IAF above which metabolic disturbances will be increased and were determined to be 110 cm 2 ROC L negative values indicate levels of IAF below which CVD risk will not be affected and were determined to be 40 cm 2 False positives were 3% and false negatives were 9% ANOVA comparing women with IAF cross-sections less than 40 cm 2 , between 40 and 110 cm 2 and more than 110 cm 2 demonstrate large differences in CVD risk profile It is suggested women who have IAF values above 110 cm 2 are in jeopardy of possessing elevated CVD risk