Evaluation of risk profiles by subcutaneous adipose tissue topography in obese juveniles

Subcutaneous adipose tissue distribution and telomere length

Background Overweight and obese individuals have a reduced life expectancy due to cardiovascular disease (CVD), type 2 diabetes, stroke and cancer. Systemic inflammation and premature telomere shortening have been discussed as potential mechanisms linking these conditions. We investigated the relation of subcutaneous adipose tissue (SAT) distribution to leukocyte relative telomere length (RTL). Methods We measured RTL in 375 participants of the observational STYJOBS/EDECTA cohort (ClinicalTrials.gov Identifier NCT00482924) using a qPCR based method. SAT distribution was determined by lipometry yielding a percent body fat value and SAT thicknesses at 15 standardized locations across the entire body. A correlation analysis between RTL, age, sex, lipometry data and conventional body measures (body mass index [BMI], waist-, hip circumference, waist-to-hip ratio, waist-to-height ratio) was calculated. The strongest determinants of RTL were determined by a stepwise multiple regression analysis. Results RTL was not associated with age or sex. RTL was significantly negatively correlated with BMI, percent body fat, waist-, hip circumference and waist-to-height ratio. Furthermore, RTL correlated with SAT at the following locations: neck, triceps, biceps, upper back, front chest, lateral chest, upper abdomen, lower abdomen, lower back, hip, front thigh, lateral thigh, rear thigh and calf. Stepwise regression analysis revealed nuchal and hip SAT as the strongest predictors of RTL. No significant association was seen between RTL and waist-to-hip ratio. Conclusions RTL is negatively associated with parameters describing body fat composure. Nuchal and hip SAT thicknesses are the strongest predictors of RTL. Central obesity appears to correlate with premature genomic aging.

Telomere shortening associates with elevated insulin and nuchal fat accumulation

Obesity and relative leucocyte telomere length (RTL) are both linked to accelerated aging and premature mortality. We examined if nuchal subcutaneous adipose tissue (SAT) thickness, a surrogate marker of central trunk-weighted obesity, is an independent predictor of RTL that provides information beyond BMI, metabolic and inflammatory markers. RTL and nuchal SAT thickness were determined in 362 participants of the STYJOBS/EDECTA study (STYrian Juvenile Obesity Study, Early DEteCTion of atherosclerosis), which included overweight individuals and matched eutrophic controls. Fasting plasma samples were used for the measurement of leptin, resistin, adiponectin, glucose, insulin, high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), liver enzymes, creatinine, cholesterol, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, oxidized LDL, triglycerides, homocysteine and uric acid. Furthermore, all participants underwent carotid artery ultrasound. Obese individuals had markedly higher body mass index (BMI), nuchal SAT thickness, hip and waist circumferences and carotid intima media thickness (IMT) than eutrophic controls. In addition, they showed typical biochemical abnormalities related to energy metabolism, systemic inflammation and liver function. RTL was inversely correlated with nuchal SAT thickness, IMT, hs-CRP, alkaline phosphatase, insulin, resistin, and leptin. Positive correlations were seen with homocysteine and creatinine. Stepwise linear regression analyses identified nuchal SAT thickness and insulin as the only significant predictors of RTL. In conclusion, nuchal SAT thickness is a robust predictor of RTL that provides information beyond traditional obesity-related metabolic and inflammatory biomarkers. This suggests an important role of fat depots at the neck for accelerated telomere shortening.

Using body mass index ignores the intensive training of elite special force personnel

Body mass index is a common and well-known measure in daily life. A body mass index higher than 25 is assumed to be an indicator for overweight and obesity and a high amount of total body fat. But body mass index overestimates body fat in subjects with high muscle mass and underestimates it in persons with a low lean body mass, especially in elderly and diseased persons. In the present study, we investigate the performance of the body mass index as a measure of body fatness and its ability to distinguish between well-trained and untrained subjects. Twenty-one well-trained male members of a police task force named “Cobra” and 38 non-active controls, matched by age, weight and height were participants of the study. The age range of these subjects was between 30 and 45 years. Subcutaneous adipose tissue thicknesses and body fat distributions were measured non-invasively by an optical device named the “Lipometer.” Statistics were performed with SPSS. We found that the body mass index did not show a difference between the two groups, whereas all Lipometer results were able to discriminate significantly between the trained and untrained subjects. Furthermore, the receiver operating characteristic curve analysis was calculated and all Lipometer measurements provided significant results up to a correct classification of all subjects of 86.4%, which was for the lateral thigh body site. In conclusion, the body mass index was not able to recognize the difference between trained and untrained participants, while body fat distribution measured with the Lipometer was able to distinguish more clearly the large body fat differences between these two groups.

Impact statement

Body mass index (BMI) is a common measure of body fatness but overestimates body fat in subjects with high muscle mass. We have developed previously a device named “Lipometer,” an alternative way to measure body fatness. We show herein that the Lipometer is able to distinguish more clearly (than the BMI) the large body fat differences between well-trained and untrained subjects. Thus, the Lipometer is superior to BMI with respect to body fat measurements.

Past and future corollaries of theories on causes of metabolic syndrome and obesity related co-morbidities part 2: a composite unifying theory review of human-specific co-adaptations to brain energy consumption

Metabolic syndrome (MetS) predicts type II diabetes mellitus (TIIDM), cardiovascular disease (CVD) and cancer, and their rates have escalated over the last few decades. Obesity related co-morbidities also overlap the concept of the metabolic syndrome (MetS). However, understanding of the syndrome's underlying causes may have been misapprehended. The current paper follows on from a theory review by McGill, A-T in Archives of Public Health, 72: 30. This accompanying paper utilises research on human evolution and new biochemistry to theorise on why MetS and obesity arise and how they affect the population. The basis of this composite unifying theory is that the proportionately large, energy-demanding human brain may have driven co-adaptive mechanisms to provide, or conserve, energy for the brain. A 'dual system' is proposed. 1) The enlarged, complex cortico-limbic-striatal system increases dietary energy by developing strong neural self-reward/motivation pathways for the acquisition of energy dense food, and (2) the nuclear factor-erythroid 2-related factor 2 (NRF2) cellular protection system amplifies antioxidant, antitoxicant and repair activity by employing plant chemicals. In humans who consume a nutritious diet, the NRF2 system has become highly energy efficient. Other relevant human-specific co-adaptations are explored. In order to 'test' this composite unifying theory it is important to show that the hypothesis and sub-theories pertain throughout the whole of human evolution and history up till the current era. Corollaries of the composite unifying theory of MetS are examined with respect to past under-nutrition and malnutrition since agriculture began 10,000 years ago. The effects of man-made pollutants on degenerative change are examined. Projections are then made from current to future patterns on the state of 'insufficient micronutrient and/or unbalanced high energy malnutrition with central obesity and metabolic dysregulation' or 'malnubesity'. Forecasts on human health are made on positive, proactive strategies using the composite unifying theory, and are extended to the wider human ecology of food production. A comparison is made with the outlook for humans if current assumptions and the status quo on causes and treatments are maintained. Areas of further research are outlined. A table of suggestions for possible public health action is included.

PreDictor Research in Obesity during Medical care - weight Loss in children and adolescents during an INpatient rehabilitation: rationale and design of the DROMLIN study

BACKGROUND

Obesity in adults and children is increasing worldwide at alarming rates. Obese children and adolescents are likely to become obese adults with increased risk of a number of comorbidities. In addition to preventing the development of obesity at young age, it is necessary to individualize the therapy of already obese children and adolescents in order to increase the likelihood of weight loss and maintenance. Therefore, the aim of this study is to identify predictors which play a significant role in successful weight loss and weight loss maintenance in children and adolescents.

METHODS/DESIGN

Over a one year period, 60 obese children and adolescents between 9 to 17 years of age shall be recruited at an inpatient children rehabilitation facility in Germany. They will be investigated twice within a few days following admission and prior to discharge. The study will be an integrated component of an established inpatient weight-loss and in part psychosomatic therapy. The collected data can be grouped into four clusters: 1) demographic, sociometric and psychometric data, 2) objective and subjective parameters of body condition, 3) autonomic nervous system regulated functions and 4) objective and subjective parameters for eating behavior. Primary outcome is the change of the body mass index standard deviation score (BMI-SDS). In order to evaluate the data appropriately, all examinations will be also conducted in a normal-weight reference group, matched for age and gender.

DISCUSSION

For some of the collected parameters the time span between measures may be too short. Therefore, a 6 months, 1 year and 2 year follow-up will be performed for evaluating the different predictors and their influence in regard to a successful intervention. Further middle- and long-term follow-up studies are planned.

TRIAL REGISTRATION

The study protocol was approved by the Ethics Committee of the University Hospital Tübingen, Germany. This study is registered at the German Clinical Trials Register (DRKS) with the clinical trial number DRKS00005122.

Normal weight estonian prepubertal boys show a more cardiovascular-risk-associated adipose tissue distribution than austrian counterparts

Objective. Risk phenotypes for cardiovascular disease (CVD) differ markedly between countries, like the reported high difference in CVD mortality in Austria and Estonia. Hitherto, the goal of this study was to find out risk profiles in body fat distribution yet present in childhood, paving the way for later clinical end points. Methods. he subcutaneous adipose tissue (SAT) distribution patterns in 553 Austrian (A) and Estonian (E) clinically healthy normal weight boys aged 11.1 (±0.8) years were analysed. We applied the patented optical device Lipometer which determines the individual subcutaneous adipose tissue topography (SAT-Top). Results. Total body fat did not differ significantly between E and A boys. A discriminant analysis using all Lipometer data, BMI, and the total body fat (TBF) yielded 84.6% of the boys correctly classified in Estonians and Austrians by 9 body sites. A factor analysis identified the SAT distribution of E as critically similar to male adult patients with coronary heart disease (CHD). Conclusions. We show in normal weight Estonian boys a highly significant decreased fat accumulation on the lower body site compared to age matched Austrian males. This SAT-Top phenotype may play an important role for the increased cardiovascular risk seen in the Estonian population.

Fatty liver index in polycystic ovary syndrome

INTRODUCTION

Women with polycystic ovary syndrome (PCOS) frequently suffer from metabolic disturbances and might be affected by hepatic steatosis. The fatty liver index (FLI) was developed as a simple and accurate predictor of hepatic steatosis. We aimed to analyze the association of FLI with endocrine and metabolic parameters in a cohort of PCOS and control women.

METHODS

FLI was calculated using body mass index (BMI), waist circumference, triglycerides, and gamma-glutamyl transferase in 611 PCOS and 139 BMI-matched control women within the same age range. Elevated FLI was defined as >60. Metabolic, endocrine, and anthropometric measurements and oral glucose tolerance tests were performed.

RESULTS

PCOS women had significantly higher FLI levels than control women in age-adjusted analyses (11.4 (4.3-48.8) and 8.8 (3.9-35.0), respectively, P=0.001), whereas fibrosis indices were similar (aspartate amino transferase-to-platelet ratio index) or lower (FIB-4) respectively. In binary logistic regression analysis adjusted for age, odds ratio (OR) for elevated FLI was 2.52 (1.31-4.85), P=0.006, for PCOS women when compared with controls. PCOS women with high FLI levels had an adverse anthropometric, metabolic, and endocrine risk profile. The prevalence of elevated FLI was 88.7% in PCOS women with metabolic syndrome (MS) and 11.3% in PCOS women without MS (P<0.001). In control women, elevated FLI was present in 66.7% of women with MS and 30.8% of women without MS.

CONCLUSION

High FLI levels are a common finding in obese PCOS women and are closely linked to MS. FLI calculation might be a useful tool for identifying PCOS patients at high risk for metabolic and hepatic disturbances.

N-terminal pro-B-type natriuretic peptide in early and advanced phases of obesity

BACKGROUND

Increased plasma amino-terminal-cleavage-fragment of NP (NT-proBNP) is an established indicator for heart failure. Moreover, obese adults had low circulating NT-proBNP suggesting an obesity-related dysregulation (natriuretic handicap). Secretion and/or clearance of NT-proBNP were discussed to be impaired in obesity. As only older adults were investigated so far, it remains unclear when during the evolution of obesity the state of a natriuretic handicap develops, and whether NT-proBNP may still serve as a relevant cardiac marker in obese juveniles.

METHODS

We analysed NT-proBNP in juvenile (n=274, 10-18 years) and middle-aged (n=277, 18-50 years) normal weight (n=213) and obese (n=338) probands together with complex anthropometry, carotis sonography, clinical, and laboratory parameters.

RESULTS

NT-proBNP showed a significant gender and age interaction. Adult females had significant higher NT-proBNP than adult males, and higher levels than juvenile females. Adult males had lower levels than juvenile males. Only a weak age and weight interaction was seen with obese juveniles which showed higher NT-proBNP than obese adults. Moreover, normal weight probands had higher NT-proBNP than overweight and obese. In a multiple regression including all probands, gender, creatinine and uric acid were the best predictors for NT-proBNP. In adults, female gender is the strongest driver for increased NT-proBNP.

CONCLUSIONS

These results argue against an essential influence of obesity to B-type cardiac natriuretic hormone system regulation in the absence of heart failure, and suggest NT-proBNP as a useful cardiac marker irrespective of age and obesity.

High density lipoprotein cholesterol level is a robust predictor of lipid peroxidation irrespective of gender, age, obesity, and inflammatory or metabolic biomarkers

BACKGROUND

Obesity related dyslipidemia, chronic inflammation and oxidative stress were associated with atherosclerotic sequels. We analysed oxidized low-density lipoprotein (oxLDL) plasma levels of 797 participants of the STyrian Juvenile OBesity (STYJOBS) / Early DEteCTion of Atherosclerosis (EDECTA) Study cohort aged from 5 to 50 years. The rationale of STYJOBS/EDECTA is to investigate the preclinical phase of obesity by a well defined cohort of young and middle aged overweight/obese and normal weight subjects.

METHODS AND RESULTS

Plasma oxLDL was analysed by ELISA (Mercodia, Sweden). In the overweight/obese (OW/OB) study group, oxLDL levels were significantly increased compared to normal weighted controls (p<0.001). Probands with metabolic syndrome (MS) had significantly higher oxLDL levels than probands without MS; between overweight and obese participants, and between females and males, no significant difference was seen. In a multiple stepwise regression analysis including all study subjects, age, gender, anthropometric data, presence of metabolic syndrome, systolic, diastolic blood pressure, carotis communis intima media thickness, lipids, adipokines, metabolic, and inflammatory biomarkers, decreased high-density lipoprotein (HDL-cholesterol) and increased total cholesterol were the best predictors for increased oxLDL levels.

CONCLUSION

Decreased HDL-cholesterol is an important determinant of lipid peroxidation irrespective of obesity, age, gender, SAT distribution, and inflammatory/metabolic biomarkers.

Serum neopterin is not increased in obese juveniles

Objective. Cardiovascular disease is associated with inflammation and immune activation, concentrations of immune activation markers like neopterin predict outcome in adults. Methods. Serum neopterin concentrations and early metabolic and pre-atherosclerotic symptoms were analyzed in 295 obese juveniles and 101 normal weight controls of similar age. Additionally, the influence of a 12 months weight reduction program on neopterin levels was investigated in 31 obese juveniles. Results. Intima-media thickness of common carotid arteries (IMT) and the concentrations of C-reactive protein (CRP) were increased in the obese juveniles (P < .001). Also triglycerides, oxidized LDL, fasted insulin levels, HOMA-index, leptin, liver transaminases and uric acid were increased compared to the controls. However, serum neopterin was decreased in the obese versus non-obese juveniles (P < .03). The intervention consisting of regular sports, nutritional devices, and a psychologic attendance led after 12 months to an increase of neopterin concentration (P < .05; paired test). Conclusions. Neopterin concentrations in juvenile obesity behaved considerably different from what was demonstrated in adults, levels did not correlate with metabolic and pre-atherosclerotic symptoms found in early phases although early vascular burden and chronic low grade inflammation was indicated by increased IMT and CRP. Neopterin concentrations increased after a 12 months intervention program.

Insulin and hippocampus activation in response to images of high-calorie food in normal weight and obese adolescents

Responsiveness to food cues, especially those associated with high-calorie nutrients may be a factor underlying obesity. An increased motivational potency of foods appears to be mediated in part by the hippocampus. To clarify this, we investigated by means of 3-T magnetic resonance imaging (MRI) the activation of the hippocampus and associated brain structures in response to pictures of high-calorie and low-calorie foods in 12 obese and 12 normal-weight adolescents. To investigate the relationship between neuronal activation patterns (e.g., hippocampus) to the caloric content of food images and plasma insulin levels, we performed a multiple regression analysis. Interestingly, a significant positive correlation between fasting plasma levels of insulin, waist circumference, and right hippocampal activation was seen after stimulation with high-caloric food images. BMI values did not correlate significantly with the hippocampal activation. On the other hand, we found a significant negative correlation in response to high-caloric food images and the plasma levels of insulin in the medial right gyrus frontalis superior and in the left thalamus. In summary, our data show that insulin is importantly involved in the central regulation of food intake. The significant positive relationship between hippocampal activation after stimulation with high-caloric food images, plasma insulin levels, and waist circumference suggests a permissive role of insulin signaling pathways in the hippocampal control of eating behavior. Interestingly, only the waist circumference, as a main indicator of abdominal obesity, correlated significantly with the hippocampal activation patterns, and not the BMI.

Subcutaneous adipose tissue topography and metabolic disturbances in polycystic ovary syndrome

OBJECTIVE

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder affecting women of reproductive age. Central obesity plays a major role in the pathophysiology of PCOS. However, there is little information on the impact of subcutaneous adipose tissue (SAT) on metabolic disturbances in PCOS. The aim of this study was to investigate whether SAT topography influences insulin resistance, impaired glucose tolerance and metabolic parameters in women with PCOS.

METHODS

36 women aged 16-41 years with PCOS and 87 healthy women aged 20-34 years were examined using lipometry, metabolic and hormonal measurements, oral glucose tolerance tests, hirsutism scores, and questionnaires. The homeostasis model assessment (HOMA) index was used for determination of insulin resistance.

RESULTS

SAT measurement points on the trunk showed significant positive correlation with the HOMA index. A negative correlation between calf SAT and the HOMA index was seen. Multiple regression analysis detected a positive association between the HOMA index and lower-abdomen SAT and upper-back SAT, whereas hip SAT showed a negative association with the HOMA index. In overweight/obese patients with PCOS, lower-abdomen and upper-back SAT showed significant positive correlations with insulin resistance. There was no correlation of SAT topography with insulin resistance in lean women with PCOS. Compared with PCOS women with normal glucose tolerance, patients with glucose intolerance had significantly increased trunk obesity and decreased leg fat. Increased SAT layers on the trunk were related to an unfavorable serum lipid profile, whereas increased leg fat correlated positively with HDL cholesterol.

CONCLUSIONS

Increased SAT layers on the trunk are associated with insulin resistance, impaired glucose tolerance and an unfavorable lipid profile in women suffering from PCOS. Increased thickness of leg SAT emerges as being protective against metabolic disturbances in PCOS.

ROC analysis of subcutaneous adipose tissue topography (SAT-Top) in female coronary heart disease patients and healthy controls

The aim of this study was to investigate whether subcutaneous adipose tissue topography (SAT-Top) is different in female CHD patients (n=26) and healthy controls (n=36) matched to age, body size, weight, and BMI. The thicknesses of SAT layers were measured by LIPOMETER at 15 specified body sites. To calculate the power of the different body sites to discriminate between CHD women and healthy controls, receiver operating characteristic (ROC) curve analysis was performed. For each parameter, sensitivity and specificity were calculated at different cutoff points. CHD women showed a significant decrease to 78.36% (p=0.012) at body site 11-front thigh, 73.10% (p=0.012) at 12-lateral thigh, 72.20% (p=0.009) at 13-rear thigh, 66.43% (p<0.001) at 14-inner thigh, and 49.19% (p<0.001) at 15-calf. The best discriminators analysed by ROC curves between female CHD patients and healthy controls turned out to be calf and inner thigh (optimal cut off values: calf: 3.85 mm and inner thigh: 11.15 mm). Stepwise discriminant analysis identified the body sites calf, lateral chest, and inner thigh as significant. In conclusion, information was obtained on the extent to which SAT thickness at each measured body site is able to discriminate between the two subject groups. The good discrimination results obtained for the present dataset are encouraging enough to recommend applying LIPOMETER SAT-Top measurements in further studies to investigate individual risks for CHD.