Measuring adiposity in patients: the utility of body mass index (BMI), percent body fat, and leptin

Metabolic Risk Factors in Young Men With Healthy Body Fat But Different Level of Physical Activity

The study was performed to evaluate metabolic risk in young lean individuals characterized by different physical activity. A total of 194 students (93 active with 5–7 h weekly physical activity and 101 inactive) were accepted for the study. The following percentages of body fat were accepted as characteristic for lean men: 14% to 17% in active and 18% to 24% in inactive participants. Circulating glucose, insulin, triacylglycerols (TG), total cholesterol (TC), and high-dendity lipoprotein (HDL)-cholesterol (HDL-C) were assayed. Daily intake of energy and macronutrients was briefly assessed from 24 h food records collected over 4 days preceding blood collection. Insulin and TG differed with respect to physical activity and was lower by 37.5% and 12.5%, respectively, in active versus inactive participants. In active students with upper quartile of body fat percentage, the only significant difference was found between circulating insulin (by 28%, p < .04). In inactive participants with upper quartile of body fat, significant differences were found between levels of insulin and TG (by 25% and by 37.5%, respectively). Diet composition did not differ with respect to the percentage of energy derived from protein, fat, and carbohydrates. An inverse association between insulin level and the percentage of body fat seems to be physiological one because it has been noted in both active and inactive individuals. On the contrary, elevation in circulating TG found exclusively in inactive subjects seems to be secondary to the changes in adiposity and circulating insulin and is followed by tendency to higher levels of TC.

A gene-diet interaction controlling relative intake of dietary carbohydrates and fats

OBJECTIVE

Preference for dietary fat vs. carbohydrate varies markedly across free-living individuals. It is recognized that food choice is under genetic and physiological regulation, and that the central melanocortin system is involved. However, how genetic and dietary factors interact to regulate relative macronutrient intake is not well understood.

METHODS

We investigated how the choice for food rich in carbohydrate vs. fat is influenced by dietary cholesterol availability and agouti-related protein (AGRP), the orexigenic component of the central melanocortin system. We assessed how macronutrient intake and different metabolic parameters correlate with plasma AGRP in a cohort of obese humans. We also examined how both dietary cholesterol levels and inhibiting de novo cholesterol synthesis affect carbohydrate and fat intake in mice, and how dietary cholesterol deficiency during the postnatal period impacts macronutrient intake patterns in adulthood.

RESULTS

In obese human subjects, plasma levels of AGRP correlated inversely with consumption of carbohydrates over fats. Moreover, AgRP-deficient mice preferred to consume more calories from carbohydrates than fats, more so when each diet lacked cholesterol. Intriguingly, inhibiting cholesterol biosynthesis (simvastatin) promoted carbohydrate intake at the expense of fat without altering total caloric consumption, an effect that was remarkably absent in AgRP-deficient mice. Finally, feeding lactating C57BL/6 dams and pups a cholesterol-free diet prior to weaning led the offspring to prefer fats over carbohydrates as adults, indicating that altered cholesterol metabolism early in life programs adaptive changes to macronutrient intake.

CONCLUSIONS

Together, our study illustrates a specific gene-diet interaction in modulating food choice.

Does obesity affect patient-reported outcomes following total knee arthroplasty?

Background

There is an existing perception that obesity has a negative impact on complications following total knee arthroplasty (TKA). However, data on the impact of obesity levels on patient-reported outcomes (PROMs) is sparse. We investigated the association between different obesity classes with PROMs among patients who underwent TKA.

Methods

We performed retrospective secondary analyses on data extracted from the total joint replacement data repository (Alberta, Canada) managed by the Alberta Bone and Joint Health Institute (ABJHI). Patients had WOMAC and EQ5D scores measured at baseline in addition to 3 and/or 12 months following TKA. Patients were stratified according to the World Health Organization (WHO) classification, into five body mass index (BMI) groups of normal, overweight, BMI class I, BMI class II, and BMI class III. The association between BMI and mean changes in WOMAC subscales (pain, function, and stiffness) and EQ-5D-5L index over the time intervals of baseline to 3 months and 3 to 12 months following TKA was assessed. Linear mixed-effects models were used, and the models were adjusted for age, sex, length of surgery, comorbidities, year of surgery, and geographical zone where the surgery was performed.

Results

Mean age was 65.5 years (SD = 8.7). Postoperatively, there was a significant improvement (p < 0.001) in WOMAC subscales of patient-reported pain, function, and stiffness, as well as EQ-5D-5L regardless of BMI group. Although, patients in BMI class II and class III reported significantly improved pain 3 months after TKA compared to those with normal BMI, all BMI groups attained similar level of pain reduction at 12 months after TKA. The greatest improvement in all WOMAC subscales, as well as EQ5D index, occurred between baseline and 3 months (adjusted p < 0.0001).

Conclusion

The findings indicate that patients reported improved pain, function, and stiffness across all BMI groups following TKA. Patients with BMI classified as obese reported similar benefits to those with BMI classified as normal weight. These results may help health care providers to discuss expectations regarding the TKA recovery in terms of pain, function, and quality of life improvements with their TKA candidates.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-022-04997-4.

Definition and Diagnostic Criteria for Sarcopenic Obesity: ESPEN and EASO Consensus Statement

INTRODUCTION

Loss of skeletal muscle mass and function (sarcopenia) is common in individuals with obesity due to metabolic changes associated with a sedentary lifestyle, adipose tissue derangements, comorbidities (acute and chronic diseases) and during the ageing process. Co-existence of excess adiposity and low muscle mass/function is referred to as sarcopenic obesity (SO), a condition increasingly recognized for its clinical and functional features that negatively influence important patient-centred outcomes. Effective prevention and treatment strategies for SO are urgently needed, but efforts are hampered by the lack of a universally established SO definition and diagnostic criteria. Resulting inconsistencies in the literature also negatively affect the ability to define prevalence as well as clinical relevance of SO for negative health outcomes.

AIMS AND METHODS

The European Society for Clinical Nutrition and Metabolism (ESPEN) and the European Association for the Study of Obesity (EASO) launched an initiative to reach expert consensus on a definition and diagnostic criteria for SO. The jointly appointed international expert panel proposes that SO is defined as the co-existence of excess adiposity and low muscle mass/function. The diagnosis of SO should be considered in at-risk individuals who screen positive for a co-occurring elevated body mass index or waist circumference, and markers of low skeletal muscle mass and function (risk factors, clinical symptoms, or validated questionnaires). Diagnostic procedures should initially include assessment of skeletal muscle function, followed by assessment of body composition where presence of excess adiposity and low skeletal muscle mass or related body compartments confirm the diagnosis of SO. Individuals with SO should be further stratified into stage I in the absence of clinical complications or stage II if cases are associated with complications linked to altered body composition or skeletal muscle dysfunction.

CONCLUSIONS

ESPEN and EASO, as well as the expert international panel, advocate that the proposed SO definition and diagnostic criteria be implemented into routine clinical practice. The panel also encourages prospective studies in addition to secondary analysis of existing data sets, to study the predictive value, treatment efficacy and clinical impact of this SO definition.

Parenting Practices and Adolescents' Eating Behaviors in African American Families

Parents play an important role in developing the eating behaviors of their children by adopting specific parenting practices. As the prevalence of obesity is high amongst African American adolescents, investigations into associations of specific parenting practices and adolescents’ eating behaviors are essential. In this exploratory study, 14 African American parent–adolescent dyads were interviewed to characterize the influence of eight different parenting practices on the consumption of three main food categories (dairy, fruits and vegetables, and unhealthy snacks). The results revealed that authoritarian parenting practices were correlated with a higher BMI percentile in adolescents, whereas modeling and monitoring are correlated with a higher parent BMI. In addition, reasoning, monitoring, modeling, and authoritative parenting practices were associated with less unhealthy snack consumption among adolescents. Reasoning and monitoring were the only parenting practices associated with higher fruit and vegetable consumption. Finally, a significant correlation was found between eating fruits and vegetables and unhealthy snacks and the location of eating. In conclusion, different parenting practices and environmental factors may impact BMI and food consumption of African American dyads. The results of this study can be used to guide improvement in, and/or development of, nutritional education interventions considering the cultural differences of racial minorities.

Body Mass Index and Mild Cognitive Impairment Among Middle-Aged and Older Adults from Low- and Middle-Income Countries

BACKGROUND

The effect of weight modification on future dementia risk is currently a subject of debate and may be modified by age.

OBJECTIVE

The aim of the present study was to investigate the association between body mass index (BMI) status with mild cognitive impairment (MCI) (a preclinical stage of dementia) in middle-aged and older adults residing in six low- and middle-income countries using nationally representative data.

METHODS

Cross-sectional data from the Study on Global Ageing and Adult Health (SAGE) were analyzed. MCI was defined using the National Institute on Aging-Alzheimer's Association criteria. BMI (kg/m2) was based on measured weight and height and categorized as: underweight (<18.5), normal (18.5-24.9), overweight (25.0-29.9), and obese (≥30.0). Multivariable logistic regression analysis and meta-analysis were conducted to assess associations.

RESULTS

Data on 32,715 individuals aged ≥50 years with preservation in functional abilities were analyzed [mean (SD) age 62.1 (15.6) years; 51.7% females]. Among those aged 50-64 years, compared to normal weight, underweight (OR = 1.44; 95% CI = 1.14-1.81), overweight (OR = 1.17; 95% CI = 1.002-1.37), and obesity (OR = 1.46; 95% CI = 1.09-1.94) were all significantly associated with higher odds for MCI. In those aged ≥65 years, underweight (OR = 0.71; 95% CI = 0.54-0.95) and overweight (OR = 0.72; 95% CI = 0.55-0.94) were associated with significantly lower odds for MCI, while obesity was not significantly associated with MCI.

CONCLUSION

The results of the study suggest that the association between BMI and MCI is likely moderated by age. Future longitudinal studies are required to confirm or refute the present findings before recommendations for policy and practice can be made.

Blood lead level and nutritional status indicators in preadolescent Polish schoolchildren

BACKGROUND

Environmental pollutions with heavy metals may have toxic effects on human health and development. One of the most detrimental is lead exposure, which may disturb neurodevelopment and linear growth in children. However, data on the effect of lead exposure on nutritional and weight status in children are limited, thus this study aimed to assess the effect of blood lead (Pb) level on nutritional and weight status in preadolescent schoolchildren from the industrialized, mining region in southwestern Poland.

METHODS

Our study sample involved N = 709 schoolchildren (402 boys and 307 girls) in the preadolescent developmental period (7-11 years of age for boys and 7-10 years of age for girls). Anthropometric measurements were used to assess nutritional and weight status: body mass index (BMI), mid-upper arm circumference (MUAC) and skinfolds thicknesses (triceps, subscapular, abdominal and the sum of skinfolds). Blood Pb level was evaluated and divided into two groups: above (>3.7 μg/dL) and below median value (≤3.7 μg/dL).

RESULTS

Analysis of covariance (with children's age controlled as a covariate) revealed that children with blood Pb level above median value had significantly lower values of BMI, MUAC and all skinfolds (at least p < 0.01). However, this effect was significant only in boys, whereas in girls differences were non-significant (p > 0.05). The highest effect size of blood Pb level was noted for skinfolds thicknesses (partial η²: 0.015 for the sum of skinfolds).

CONCLUSIONS

Nutritional status in children with higher blood Pb level is significantly impaired in preadolescent boys, who appear to be more sensitive to this environmental factor. Our findings indicate a particular need for nutritional and environmental interventions among preadolescent children in regions with higher lead exposure.

Moderate differences in plasma leptin in mares have no effect on either the amino acid or the fatty acid composition of the uterine fluid

Female mammalian reproductive functions are closely linked to body condition and metabolic status. Energy homeostasis is regulated by endocrine hormones such as insulin, IGF-I, leptin and adiponectin via the hypothalamic-pituitary-adrenal axis. These metabolic hormones and their receptors are also expressed in reproductive tissues and the embryo. We investigated the relationship between circulating leptin and the fatty acid (FA) and amino acid (AA) composition of the equine uterine fluid (UF) and peripheral blood plasma (BP) by using a mass spectrometry-based approach. UF and BP were collected from ten broodmares on days 6 and 7 post ovulation, respectively. The mares were retrospectively assigned to two groups according to their BP leptin concentrations (high leptin (> 1.6 ng/ml) versus low leptin (<0.8 ng/ml)). Specific AA and FA compositions for BP and UF were found with different levels of respective metabolite abundances. The main FAs in BP were stearic, palmitic and linoleic acid. In UF, the three most abundant FAs were eicosapentaenoic, arachidonic and stearic acid. The AA profile of BP was dominated by glycine, glutamine, serine and alanine, which were likewise among the highly abundant AAs in UF. In UF, glutamic acid had by far the highest concentration. Therefore, BP leptin concentration within a physiological range do not seem to affect the specific FA nor the AA composition of the UF. The composition of the UF may therefore be mediated by local rather than by peripheral metabolic hormones.

Translation and Validation of a State-Measure of Body Image Satisfaction: The Body Image State Scale

The aim of the present study is to test the validity and reliability of the French Body Image State Scale (F-BISS). The scale was translated using a back-translation technique, with discrepancies being settled through consensus. Three hundred and twelve female participants were recruited. Convergent validity was assessed using eating disorder evaluation and social comparison. Exploratory and confirmatory factor analyses were also conducted. The translated Body Image State Scale (BISS) demonstrated good psychometric properties, with good internal consistency (α = 0.83), and adequate goodness-of-fit. The translated BISS presented a unifactorial structure, with one factor explaining 56% of the variance. The exploratory factor analysis led to the removal of a single item due to insufficient factor loading (<0.45). Its convergent validity seems consistent with previous literature. Discriminant analyses showed a significant difference in F-BISS score between participants relative to eating disorder symptomatology (t = 11.65; p < 0.001). This translation could prove useful in both research and clinical settings to assess state body satisfaction in French populations.

The modifying effects of adiposity on the cardiovascular safety of sulphonylureas

AIMS

To determine whether adiposity modified the effect on the cardiovascular safety of sulphonylureas as a first-line therapy compared with metformin among patients with type 2 diabetes.

MATERIALS AND METHODS

Using the UK Clinical Practice Research Datalink, we conducted a cohort study among 13 862 new sulphonylurea users matched on body mass index (BMI) and propensity score, in a 1:1 ratio, to new metformin users between April 1, 1998 and December 31, 2016. Cox proportional hazards models were used to estimate hazard ratios (HRs) with 95% confidence intervals (CIs) of major adverse cardiovascular events (MACE), individual components of MACE (myocardial infarction [MI], ischaemic stroke, cardiovascular mortality), and all-cause mortality, comparing use of sulphonylureas with use of metformin, overall and within BMI categories (≤24.9 kg/m² , 25.0-29.9 kg/m² , ≥30 kg/m² ).

RESULTS

Compared with metformin, sulphonylureas were not associated with an increased risk of MACE either overall (HR 1.08, 95% CI 0.94-1.23) or by BMI category. Similar findings were observed for MI and ischaemic stroke. By contrast, sulphonylureas were associated with an increased risk of cardiovascular mortality (HR 1.24, 95% CI 1.04-1.48), primarily among obese patients (HR 1.52, 95% CI 1.08-2.13), and not among normal-weight patients (HR 1.00, 95% CI 0.72-1.39; P-interaction 0.21). Similar results were observed for all-cause mortality (HR 1.47, 95% CI 1.32-1.62), where an increased risk was observed among obese patients (HR 1.83, 95% CI 1.49-2.25), but not normal-weight patients (HR 1.18, 95% CI 0.99-1.42; P-interaction: 0.006).

CONCLUSION

The findings of this study suggest that adiposity may have a modifying effect on the association between sulphonylureas and cardiovascular and all-cause mortality compared with metformin.

Exploring the experience of being viewed as "not sick enough": a qualitative study of women recovered from anorexia nervosa or atypical anorexia nervosa

BACKGROUND

Despite common misconceptions, an individual may be seriously ill with a restrictive eating disorder without an outwardly recognizable physical sign of the illness. The aim of this qualitative study was to investigate the perspectives of individuals who have previously battled a restrictive eating disorder who were considered "not sick enough" by others (e.g., peers, families, healthcare professionals) at some point during their illness, and to understand the perceived impact on the illness and recovery. Such misconceptions are potentially damaging, and have been previously linked with delayed help-seeking and poorer clinical outcomes.

METHODS

Seven women who had recovered from anorexia nervosa or atypical anorexia nervosa participated in semi-structured interviews. Interviews were transcribed and interpretive phenomenological analysis was used.

RESULTS

Three main themes emerged: (1) dealing with the focus upon one's physical appearance while battling a mental illness, (2) "project perfect": feeling pressure to prove oneself, and (3) the importance of being seen and understood. Participants reported that their symptoms were occasionally met with trivialization or disbelief, leading to shame, confusion, despair, and for some, deterioration in eating disorder symptoms which drove further weight loss. In contrast, social support and being understood were viewed as essential for recovery.

CONCLUSION

To facilitate treatment seeking and engagement, and to optimize chances of recovery, greater awareness of diverse, non-stereotypical presentations of restrictive eating disorders is needed which challenge the myth that weight is the sole indicator of the presence or severity of illness.

Sex-specific associations of body composition measures with cardiac function and structure after 8 years of follow-up

We investigated the prospective associations of body composition with cardiac structure and function and explored effect modification by sex and whether inflammation was a mediator in these associations. Total body (BF), trunk (TF) and leg fat (LF), and total lean mass (LM) were measured at baseline by a whole body DXA scan. Inflammatory biomarkers and echocardiographic measures were determined both at baseline and follow-up in the Hoorn Study (n = 321). We performed linear regression analyses with body composition measures as determinant and left ventricular ejection fraction (LVEF), left ventricular mass index (LVMI) or left atrial volume index (LAVI) at follow-up as outcome. Additionally, we performed mediation analysis using inflammation at follow-up as mediator. The study population was 67.7 ± 5.2 years and 50% were female. After adjustment, BF, TF and LF, and LM were associated with LVMI with regression coefficients of 2.9 (0.8; 5.1)g/m^2.7, 2.3 (0.6; 4.0)g/m^2.7, 2.0 (0.04; 4.0)g/m^2.7 and − 2.9 (− 5.1; − 0.7)g/m^2.7. Body composition measures were not associated with LVEF or LAVI. These associations were not modified by sex or mediated by inflammation. Body composition could play a role in the pathophysiology of LV hypertrophy. Future research should focus on sex differences in regional adiposity in relation with diastolic dysfunction.

Hypothesizing Nutrigenomic-Based Precision Anti-Obesity Treatment and Prophylaxis: Should We Be Targeting Sarcopenia Induced Brain Dysfunction?

Background: The United States Centers for Disease Control and Prevention (CDC) estimates a total obesity rate of 30% for 12 states and a 20% obesity rate nationwide. The obesity epidemic continues to increase in spite of preventative measures undertaken worldwide. Pharmacological treatments promise to reduce total fat mass. However, medications may have significant side effects and can be potentially fatal. Data Retrieval: This brief review, based on a PUBMED search of the key terms "Obesity" and" Sarcopenia," will present evidence to corroborate the existence of Reward Deficiency Syndrome (RDS) in obesity and the involvement of catecholaminergic pathways in substance seeking behavior, particularly as it relates to carbohydrates cravings. Expert Opinion: The genetic basis and future genetic testing of children for risk of aberrant generalized craving behavior are considered a prevention method. Here we present evidence supporting the use of precursor amino acid therapy and modulation of enkephalinase, MOA, and COMT inhibition in key brain regions. Such treatments manifest in improved levels of dopamine/norepinephrine, GABA, serotonin, and enkephalins. We also present evidence substantiating insulin sensitivity enhancement via Chromium salts, which affect dopamine neuronal synthesis regulation. We believe our unique combination of natural ingredients will influence many pathways leading to the promotion of well-being and normal healthy metabolic functioning. Sarcopenia has been shown to reduce angiogenesis and possible cerebral blood flow. Exercise seems to provide a significant benefit to overcome this obesity-promoting loss of muscle density. Conclusion: Utilization of proposed nutrigenomic formulae based on coupling genetic obesity risk testing promotes generalized anti-craving of carbohydrates and can inhibit carbohydrate bingeing, inducing significant healthy fat loss and relapse prevention.

Associations between body mass index and the surgical phenotype and location of endometriotic lesions

RESEARCH QUESTION

Is there a relationship between body mass index (BMI) and endometriotic lesions, specifically surgical phenotype and lesion location?

DESIGN

An observational retrospective cohort study at the Royal Women's Hospital, Melbourne, Australia, including 471 histologically confirmed endometriosis patients. Statistical analyses included multivariate logistic regression and multivariate modelling, correcting for multiple testing. Outcomes were the presence or absence of surgically classified lesion phenotypes, as per revised American Society for Reproductive Medicine criteria including superficial or deep, peritoneal or ovarian, and adhesions (Study I); and lesions at specific anatomical locations (including pelvic side wall, uterosacral ligament, pouch of Douglas, ovarian, uterovesical fold, bladder, and pararectal endometriosis) (Study II).

RESULTS

In Study I, patients with higher BMI were more likely to have superficial peritoneal lesions (odds ratio [OR] 1.070, 95% confidence interval [CI] 1.004-1.144; P = 0.044), and less likely to have deep ovarian lesions (OR 0.928, 95% CI 0.864-0.993; P = 0.034). In Study II, patients with higher BMI were less likely to have uterovesical fold lesions (OR 0.927, 95% CI 0.867-0.985; P = 0.021) or anterior compartment lesions (OR 0.940, 95% CI 0.888-0.989; P = 0.023). After correcting for multiple testing, the relationship between BMI and lesion phenotypes did not persist (P > 0.01).

CONCLUSIONS

This analysis does not conclusively support an influence of BMI on endometriotic lesion phenotype based on surgical classification or location. Further investigation of the physiological disturbances underlying BMI and the promotion of endometriotic lesion phenotypes and their location is warranted, but any effect is likely to be small.

Longitudinal Analysis of Psychosocial Stressors and Body Mass Index in Middle-Aged and Older Adults in the United States

OBJECTIVES

Psychosocial stress may be a risk factor for obesity and overweight in middle-aged and older adults. However, research on psychosocial stress and excess body weight has typically been cross-sectional and focused on single stressors.

METHODS

Using 3 waves of data from the Health and Retirement Study, we conducted longitudinal analyses to assess associations between 5 psychosocial stressors-individually and in combination-and body mass index (BMI), adjusting for sociodemographic factors, alcohol use, and smoking history. We tested interaction effects between race and gender with stressors on BMI.

RESULTS

A total of 3,956 participants were included in the main analyses. Most participants were White (88.04%) and more than half were female (60.39%). Perceived discrimination, financial stress, and relationship stress were positively associated with BMI. A greater cumulative stress burden was associated with higher BMI. In stratified analyses, greater financial stress was associated with higher BMI among White participants, whereas greater neighborhood stress was associated with lower BMI among Black participants. Greater relationship stress, financial stress, cumulative high stress, and overall cumulative stress burden were associated with higher BMI for women, but not men.

DISCUSSION

Different sources of stress may be risk factors to weight gain and affect BMI in adults. White and female adults may be more susceptible to the obesogenic effects of stressors. Reducing exposure to stress may help reduce the burden of high BMI among middle-aged and older adults.

Construct and Predictive Validity of Sarcopenia in Lung Transplant Candidates

Rationale: Sarcopenia is associated with disability and death. The optimal definition and clinical relevance of sarcopenia in lung transplantation remain unknown. Objectives: To assess the construct and predictive validity of sarcopenia definitions in lung transplant candidates. Methods: In a multicenter prospective cohort of 424 lung transplant candidates, we evaluated limited (muscle mass only) and expanded (muscle mass and quality) sarcopenia definitions from the European Working Group on Sarcopenia in Older People 2 (EWGSOP2), the Foundation for the National Institutes of Health (FNIH), and a cohort-specific distribution-based lowest quartile definition. We assessed construct validity using associations with conceptually related factors. We evaluated the relationship between sarcopenia and frailty using generalized additive models. We also evaluated associations between sarcopenia definitions and key pretransplant outcomes, including disability (quantified by the Lung Transplant Valued Life Activities scale [range, 0-3; higher scores = worse disability; minimally important difference, 0.3]) and waitlist delisting/death, by multivariate linear and Cox regression, respectively. Results: Sarcopenia prevalence ranged from 6% to13% by definition used. The limited EWGSOP2 definition demonstrated the highest construct validity, followed by the expanded EWGSOP2 definition and both limited and expanded FNIH and lowest quartile definitions. Sarcopenia exhibited a linear association with the risk of frailty. The EWGSOP2 and expanded lowest quartile definitions were associated with disability, ranging from 0.20 to 0.25 higher Lung Transplant Valued Life Activities scores. Sarcopenia was associated with increased risk of waitlist delisting or death by the limited and expanded lowest quartile definitions (hazard ratio [HR], 3.8; 95% confidence interval [CI], 1.4-9.9 and HR, 3.5; 95% CI, 1.1-11.0, respectively) and the EWGSOP2 limited definition (HR, 2.8; 95% CI, 0.9-8.6) but not with the three other candidate definitions. Conclusions: The prevalence and validity of sarcopenia vary by definition; the EWGSOP2 limited definition exhibited the broadest validity in lung transplant candidates. The linear relationship between low muscle mass and frailty highlights sarcopenia's contribution to frailty and also questions the clinical utility of a sarcopenia cut-point in advanced lung disease. The associations between sarcopenia and important pretransplant outcomes support further investigation into using body composition for candidate risk stratification.

Prevalence of Normal Weight Obesity and Health Risk Factors for the Female Collegiate Dancer

ABSTRACT

Brown, AF, Alfiero, CJ, Brooks, SJ, Kviatkovsky, SA, Smith-Ryan, AE, and Ormsbee, MJ. Prevalence of normal weight obesity and health risk factors for the female collegiate dancer. J Strength Cond Res 35(8): 2321-2326, 2021-The purpose of this study was to investigate the prevalence of normal weight obesity (NWO) and evaluate the relationship between NWO and health risk factors in a collegiate dancer population. Reanalysis of data of female dancers (N = 42) from 2 larger studies was used to assess prevalence and health risk factors of NWO. Dancers completed a dual-energy x-ray absorptiometry scan to assess fat mass (FM), lean mass (LM), and visceral adipose tissue (VAT) and a 3-day food record. Normal weight obesity was defined as a body mass index (BMI) of 18.5-24.9 kg·m-2 and body fat (BF) ≥30%. Twenty-five (60%) dancers were classified as normal weight lean (NWL), and 17 dancers (40%) were classified as NWO. Significant differences were observed for BMI (NWL: 21.1 ± 1.7, NWO: 23.1 ± 1.6, p < 0.001), LM (NWL: 71.0 ± 2.9%, NWO: 62.5 ± 2.7%, p < 0.001), %BF (NWL: 24.8 ± 3.1%, NWO: 33.9 ± 2.6%, p < 0.001), and VAT (NWL: 130.6 ± 43.0 g, NWO: 232.3 ± 70.8 g, p < 0.001) between NWL and NWO. A significant difference was observed for carbohydrate intake (NWL: 4.7 ± 1.8 g·kg-1, NWO: 3.7 ± 1.0 g·kg-1, p = 0.020) between groups. Significant positive correlations with FM were observed between carbohydrate (kcal, p = 0.048), fat (kcal, p = 0.018; g·kg-1, p = 0.040), and total calories (p = 0.019) in NWO. Normal weight obesity in collegiate dancers may be more prevalent than previously perceived and may be significantly related to important health risk factors. The current study demonstrates the need for body composition assessments and emphasizing on promoting overall health in collegiate dancers.

Exploring the association between measures of obesity and measures of trip-induced fall risk among older adults

OBJECTIVE

Explore the association between measures of obesity and measures of trip-induced fall risk among community-dwelling older adults.

DESIGN

Case-control SETTING: Gait laboratory PARTICIPANTS: Voluntary sample of 55 community-dwelling older adults (≥65 years of age) with body mass index (BMI) of 18.84-44.68 kg/m².

INTERVENTIONS

Not applicable MAIN OUTCOMES MEASURES: Measures of obesity included six anthropometry-based measures (BMI; thigh, hip and waist circumferences; ratio of waist-to-hip circumference; and index of central obesity) and four DEXA-based measures (percent trunk, leg and total fat; and fat mass index). Measures of risk of tripping during overground walking included median and interquartile range of toe clearance, and area under the swing phase toe trajectory. Measures of trip recovery after a laboratory-induced trip included trunk angle and angular velocity at ground contact of the first recovery step, anteroposterior distance from stepping foot to center of mass at the same instant, and step time of the first recovery step.

RESULTS

Risk of tripping was associated with waist-to-hip ratio and thigh circumference. After grouping participants by waist-to-hip ratio, those with high ratios (≥0.9 cm for males and ≥0.85 cm for females) exhibited significantly greater variability in toe clearance. Trip recovery was associated with hip circumference, thigh circumference, fat mass index, and total fat. After grouping participants by fat mass index, those with high indices (>9 kg/m² for males and >13 kg/m² for females) exhibited less favorable trunk kinematics following a laboratory-induced trip (Cohen's d=0.84).

CONCLUSION

Waist-to-hip ratio and fat mass index may more closely relate to trip-induced fall risk than BMI among community-dwelling older adults.

Level of obesity is directly associated with complications following arthroscopic rotator cuff repair

BACKGROUND

The purpose of this study was to investigate the association between increasing levels of obesity and postoperative complications within 30 days of arthroscopic rotator cuff repair (ARCR).

METHODS

We queried the American College of Surgeons National Surgical Quality Improvement Program database for all patients who underwent ARCR from 2015 to 2017. Patients were stratified into 3 cohorts according to their body mass index (BMI). Patients with a BMI < 30 kg/m² were placed in the non-obese cohort, patients with a BMI between 30 and 40 kg/m² were placed in the obese cohort, and patients with a BMI > 40 kg/m² were placed in the morbidly obese cohort. Postoperative complications within 30 days of the procedure were collected. Multivariate logistic regression was used to investigate the relationship between increasing levels of obesity and postoperative complications.

RESULTS

There were 18,521 patients included in this study. Of these patients, 9548 (51.6%) were non-obese, 7438 (40.2%) were obese, and 1535 (8.3%) were morbidly obese. A comparison among non-obese, obese, and morbidly obese patients showed increasing rates of medical complications (0.5% vs. 1.0% vs. 1.4%), pulmonary complications (0.1% vs. 0.3% vs. 0.5%), renal complications (0.0% vs. 0.1% vs. 0.2%), readmission (0.9% vs. 1.2% vs. 1.6%), nonhome discharge (0.4% vs. 0.5% vs. 1.2%), and overall complications (0.8% vs. 1.3% vs. 1.8%). In comparison to non-obesity, both obesity and morbid obesity were identified by multivariate analysis as significant predictors of medical complications (odds ratio [ORs] of 1.72 and 2.16, respectively), pulmonary complications (ORs of 2.66 and 4.06, respectively), and overall complications (ORs of 1.52 and 1.77, respectively).

CONCLUSION

This study used a large national database to identify increasing levels of obesity as a risk factor for medical complications, pulmonary complications, and overall complications within 30 days of ARCR.

Genomic insights into body size evolution in Carnivora support Peto's paradox

Background

The range of body sizes in Carnivora is unparalleled in any other mammalian order—the heaviest species is 130,000 times heavier than the lightest and the longest species is 50 times longer than the shortest. However, the molecular mechanisms underlying these huge differences in body size have not been explored.

Results

Herein, we performed a comparative genomics analysis of 20 carnivores to explore the evolutionary basis of the order’s great variations in body size. Phylogenetic generalized least squares (PGLS) revealed that 337 genes were significantly related to both head body length and body mass; these genes were defined as body size associated genes (BSAGs). Fourteen positively-related BSAGs were found to be associated with obesity, and three of these were under rapid evolution in the extremely large carnivores, suggesting that these obesity-related BSAGs might have driven the body size expansion in carnivores. Interestingly, 100 BSAGs were statistically significantly enriched in cancer control in carnivores, and 15 of which were found to be under rapid evolution in extremely large carnivores. These results suggested that large carnivores might have evolved an effective mechanism to resist cancer, which could be regarded as molecular evidence to support Peto’s paradox. For small carnivores, we identified 15 rapidly evolving genes and found six genes with fixed amino acid changes that were reported to reduce body size.

Conclusions

This study brings new insights into the molecular mechanisms that drove the diversifying evolution of body size in carnivores, and provides new target genes for exploring the mysteries of body size evolution in mammals.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-021-07732-w.

Adiposity and Interstitial Lung Abnormalities in Community-Dwelling Adults: The MESA Cohort Study

BACKGROUND

Obesity is associated with restrictive ventilatory defects and a faster rate of decline in FVC. This association is not exclusively mediated by mechanical factors and may reflect direct pulmonary injury by adipose-derived mediators.

RESEARCH QUESTION

Is adipose tissue involved in the pathogenesis of interstitial lung disease (ILD)?

STUDY DESIGN AND METHODS

We evaluated the association of CT measures of pericardial, abdominal visceral, and abdominal subcutaneous adipose tissue with high-attenuation areas (HAAs) and interstitial lung abnormalities (ILAs) in a large multicenter cohort study of community-dwelling adults, using multivariable-adjusted models. We secondarily evaluated the association of adipose depot size with FVC and biomarkers of obesity and inflammation.

RESULTS

In fully adjusted models, every doubling in pericardial adipose tissue volume was associated with a 63.4-unit increase in HAA (95% CI, 55.5-71.3), 20% increased odds of ILA (95% CI, -2% to 50%), and a 5.5% decrease in percent predicted FVC (95% CI, -6.8% to -4.3%). IL-6 levels accounted for 8% of the association between pericardial adipose tissue and HAA. Every doubling in visceral adipose tissue area was associated with a 41.5-unit increase in HAA (95% CI, 28.3-54.7), 30% increased odds of ILA (95% CI, -10% to 80%), and a 5.4% decrease in percent predicted FVC (95% CI, -6.6% to -4.3%). IL-6 and leptin accounted for 17% and 18%, respectively, of the association between visceral adipose tissue and HAA.

INTERPRETATION

Greater amounts of pericardial and abdominal visceral adipose tissue were associated with CT measures of early lung injury and lower FVC in a cohort of community-dwelling adults. Adipose tissue may represent a modifiable risk factor for ILD.

Olive leaf extract supplementation improves the vascular and metabolic alterations associated with aging in Wistar rats

Olive leaves are rich in bioactive substances which exert anti-inflammatory, antioxidant, insulin-sensitizing and antihypertensive effects. The aim of this study was to analyze the possible beneficial effects of an olive leaf extract (OLE) rich in secoiridoids and phenolic compounds on the aging-induced metabolic and vascular alterations. Three experimental groups of rats were used: 3-month-old rats, 24-month-old rats and 24-month-old rats supplemented 21 days with OLE (100 mg/kg). Administration of OLE to aged rats decreased the weight of adrenal glands and prevented the aging-induced loss of body weight and muscle mass. In the serum, OLE reduced the circulating levels of LDL-cholesterol and IL-6 and increased the concentrations of leptin and adiponectin. In the liver OLE attenuated the decreased gene expression of SOD-1, GSR, GCK and GSK-3β and reduced the aging-induced overexpression of NOX-4, Alox-5, iNOS and TNF-α. In aorta segments, OLE prevented endothelial dysfunction and vascular insulin resistance and improved vasoconstriction in response to KCl and NA. Improvement in vascular function was associated with the attenuation of the alterations in the gene expression of COX-2, IL-6, GPx, NOX-1 and IL-10. In conclusion, OLE exerts anti-inflammatory and antioxidant effects in aged rats and attenuates the alterations in vascular function associated with aging.

Natural Killer Cells: Friend or Foe in Metabolic Diseases?

The worldwide epidemic of metabolic diseases, especially obesity and other diseases caused by it, has shown a dramatic increase in incidence. A great deal of attention has been focused on the underlying mechanisms of these pathological processes and potential strategies to solve these problems. Chronic inflammation initiated by abdominal adipose tissues and immune cell activation in obesity is the major cause of the consequent development of complications. In addition to adipocytes, macrophages and monocytes, natural killer (NK) cells have been verified to be vital components involved in shaping the inflammatory microenvironment, thereby leading to various obesity-related metabolic diseases. Here, we provide an overview of the roles of NK cells and the interactions of these cells with other immune and nonimmune cells in the pathological processes of metabolic diseases. Finally, we also discuss potential therapeutic strategies targeting NK cells to treat metabolic diseases.

Optimising weight-loss interventions in cancer patients-A systematic review and network meta-analysis

Background

Excess weight has been associated with increased morbidity and a worse prognosis in adult patients with early-stage cancer. The optimal lifestyle interventions to optimize anthropometric measures amongst cancer patients and survivors remain inconsistent.

Objective

To conduct a systematic review and network meta-analysis (NMA) of randomized controlled trials (RCTs) comparing the effects of exercise and dietary interventions alone or in combination on anthropometric measures of adult cancer patients and survivors.

Methods

A systematic search of Medline, Embase and the Cochrane Trials Registry was performed. Outcomes of interest included changes in weight, body mass index (BMI), and waist circumference. Screening and data collection were performed by two reviewers. Bayesian NMAs were performed.

Results

Overall, 98 RCTs were included; 75 were incorporated in NMAs (n = 12,199). Groups of intervention strategies included: 3 exercise interventions, 8 dietary interventions, 7 combination interventions of diet and exercise and standard care. Median intervention duration was 26 weeks. NMA suggested that diet alone (mean difference [MD] -2.25kg, 95% CrI -3.43 to -0.91kg) and combination strategies (MD -2.52kg, 95% CrI -3.54 to -1.62kg) were associated with more weight loss compared to standard care. All dietary interventions achieved a similar magnitude of weight loss (MD range from -2.03kg to -2.52kg). Both diet alone and combination strategies demonstrated greater BMI reductions versus standard care, and each of diet alone, exercise alone and combination strategies demonstrated greater reductions in waist circumference than standard care.

Conclusion

Diet and exercise alone or in combination are effective lifestyle interventions to improve anthropometric measures in cancer patients and survivors. All reputable diets appear to be similarly effective to achieve weight loss.

Obesity subtypes, related biomarkers & heterogeneity

Obesity is a serious medical condition worldwide, which needs new approaches and recognized international consensus in treating diseases leading to morbidity. The aim of this review was to examine heterogeneous links among the various phenotypes of obesity in adults. Proteins and associated genes in each group were analysed to differentiate between biomarkers. A variety of terms for classification and characterization within this pathology are currently in use; however, there is no clear consensus in terminology. The most significant groups reviewed include metabolically healthy obese, metabolically abnormal obese, metabolically abnormal, normal weight and sarcopenic obese. These phenotypes do not define particular genotypes or epigenetic gene regulation, or proteins related to inflammation. There are many other genes linked to obesity, though the value of screening all of those for diagnosis has low predictive results, as there are no significant biomarkers. It is important to establish a consensus in the terminology used and the characteristics attributed to obesity subtypes. The identification of specific molecular biomarkers is also required for better diagnosis in subtypes of obesity.

Increased modifiable cardiovascular risk factors in patients with Takayasu arteritis: a multicenter cross-sectional study

BACKGROUND

Modifiable cardiovascular risk factors (MCRFs), such as those related to aerobic capacity, muscle strength, physical activity, and body composition, have been poorly studied in Takayasu arteritis (TAK). Therefore, the aim of the study was to investigate MCRFs and their relationships with disease status and comorbidities among patients with TAK.

METHODS

A multicenter cross-sectional study was conducted between 2019 and 2020, in which 20 adult women with TAK were compared with 16 healthy controls matched by gender, age, and body mass index. The following parameters were analyzed: aerobic capacity by cardiopulmonary test; muscle function by timed-stands test, timed up-and-go test, and handgrip test; muscle strength by one-repetition maximum test and handgrip test; body composition by densitometry; physical activity and metabolic equivalent by IPAQ, quality of life by HAQ and SF-36; disease activity by ITAS2010 and NIH score; and presence of comorbidities.

RESULTS

Patients with TAK had a mean age of 41.5 (38.0-46.3) years, disease duration of 16.0 (9.5-20.0) years, and a mean BMI of 27.7±4.5 kg/m². Three out of the 20 patients with TAK had active disease. Regarding comorbidities, 16 patients had systemic arterial hypertension, 11 had dyslipidemia, and two had type 2 diabetes mellitus, while the control group had no comorbidities. TAK had a significant reduction in aerobic capacity (absolute and relative VO₂ peak), muscle strength in the lower limbs, increased visceral adipose tissue, waist-to-hip ratio, reduced walking capacity, decreased weekly metabolic equivalent, and quality of life (P< 0.05) as compared to controls. However, there were no correlations between these MCRFs parameters and disease activity.

CONCLUSIONS

TAK show impairment in MCRFs; therefore, strategies able to improve MCRF should be considered in this disease.

High-intensity interval training and essential amino acid supplementation: Effects on muscle characteristics and whole-body protein turnover

The purpose of this study was to compare the independent and combined effects of high-intensity interval training (HIIT) and essential amino acids (EAA) on lean mass, muscle characteristics of the quadriceps, and 24-hr whole-body protein turnover (WBPT) in overweight and obese adults. An exploratory aim was to evaluate potential modulatory effects of sex. Sixty-six adults (50% female; Age: 36.7 ± 6.0 yrs; %BF: 36.0 ± 7.8%) were assigned to 8 wks of: (a) HIIT, 2 days/wk; (b) EAA supplementation, 3.6 g twice daily; (c) HIIT + EAA; or (d) control. At baseline, 4 wks, and 8 wks, total body, thigh LM and muscle characteristics were measured via dual-energy x-ray absorptiometry and B-mode ultrasound, respectively. In a subsample, changes in WBPT was measured using [N15 ]alanine. Differences between groups were assessed using linear mixed models adjusted for baseline values, followed by 95% confidence intervals on adjusted mean change scores (Δ). HIIT and HIIT + EAA improved thigh LM (Δ: +0.17 ± 0.05 kg [0.08, 0.27]; +0.22 ± 0.05 kg [0.12,0.31]) and vastus lateralis cross-sectional area (Δ: +2.73 ± 0.52 cm2 [1.69,3.77]; +2.64 ± 0.53 cm2 [1.58,3.70]), volume (Δ: +54.50 ± 11.69 cm3 [31.07, 77.92]; +62.39 ± 12.05 cm3 [38.26, 86.52]), and quality (Δ: -5.46 ± 2.68a.u. [-10.84, -0.09]; -7.97 ± 2.76a.u.[-13.49, -2.45]). Protein synthesis, breakdown, and flux were greater with HIIT + EAA and EAA compared to HIIT (p < .05). Sex differences were minimal. Compared to women, men tended to respond more to HIIT, with or without EAA. For women, responses were greater with HIIT + EAA than HIIT. In overweight and obese adults, 8 weeks of HIIT, with or without EAA, improved thigh LM size and quality; EAA may enhance muscular adaptation via increases in protein turnover, supporting greater improvements in muscular size and quality.

Assessment of a proposed BMI formula in predicting body fat percentage among Filipino young adults

Body mass index (BMI), while routinely used in evaluating adiposity, cannot distinguish between fat and lean mass, and thus can misclassify weight status particularly among athletic, physically active, and tall- and short-statured individuals, whose lean-to-fat ratios and body proportions vary considerably from average individuals. Believing that the traditional BMI formula divides weight by too much with short people and by too little with tall people, University of Oxford professor L. N. Trefethen proposed a modified formula in computing BMI. This study was conducted among a sample of Filipino young adults (n = 190) to assess the performance of the modified BMI formula against the traditional one in: (1) predicting body fat percentage (%BF) measured using bioelectric impedance analysis, and (2) diagnosing overweight/obesity. Using robust polynomial regression analysis (covariates: age, waist circumference, smoking history and alcohol intake), the BMI quadratic models had the highest adjusted R2 and the lowest AIC and BIC for both sexes compared to the linear models. The AuROCs of the traditional BMI were higher than those of the proposed BMI, albeit nonsignificant. In conclusion, both traditional and modified BMIs significantly predicted %BF, as well as adequately discriminated between %BF-defined normal and overweight-obese states using optimal BMI cutoff values.

Examining the obesity paradox: A moderating effect of fitness on adipose endocrine function in older adults

Despite evidence linking obesity with increased mortality, older adults with excessive adiposity seem protected, resulting in a so-called obesity paradox. Obesity is characterized by leptin resistance, which contributes to increased risk of all-cause mortality. Therefore, lifestyle factors, such as physical fitness, that lower leptin independent of adiposity may be confounding the obesity paradox. To investigate this, we evaluated whether physical fitness moderated the relationship between leptin and adiposity. We found older adults with higher fitness had lower body mass (r(39) = -0.43, p < 0.01), leptin (r(39) = -0.29, p = 0.03) and inflammation (IL-1β: (r(39) = -0.69, p < 0.01); TNF-α: (r(39) = -0.30, p = 0.03)). Fitness moderated the relationship between leptin and adiposity (F(5, 37) = 3.73, p < 0.01, R² = 0.33) to reveal the obesity paradox in moderately and high fit individuals (b = 216.24, t(37) = 1.46, p = 0.15; b= -88.10, t(37) = -0.49, p = 0.63) but not in low fit individuals. These results show the link between obesity and mortality may not be dependent on total adiposity, but rather on endocrine function and adipocyte leptin secretion. These results have important implications for older adults struggling to maintain healthy body composition and suggest that fitness may promote overall wellbeing.

Predictive value of adipose to muscle area ratio based on MRI at knee joint for postoperative functional outcomes in elderly osteoarthritis patients following total knee arthroplasty

BACKGROUND

The current research used a new index-adipose to muscle area ratio (AMR)-to measure fatness compared with body mass index (BMI) in elderly osteoarthritis (OA) patients following total knee arthroplasty. Our study aimed to test the relationship between the two indexes (AMR and BMI) and to examine whether AMR was a predictive factor of patient-reported outcome measures (PROMS) for elderly OA patients following total knee arthroplasty (TKA).

METHODS

The retrospective data of 78 OA patients (older than 60 years) following TKA was included in our study. Clinical features of patients included age, BMI, sex, AMR, side of the implant, time of follow-up, complications, the Knee Society Score (KSS score), and the Hospital for Special Surgery knee score (HSS score). The area of adipose tissue and muscle tissue was measured on the cross section (supra-patella, midline of the patella, joint line of the knee) of the knee magnetic resonance imaging (MRI). AMR was calculated as the average of adipose to muscle area ratio at the three levels. The Pearson correlation analysis, simple linear regression, and multiple linear regression were used to study the relationship between BMI, AMR, and PROMS (KSS total-post score and HSS-post score) in the study.

RESULTS

Of all patients, the mean (± standard deviations (SD)) of age was 67.78 ± 4.91 years. For BMI and AMR, the mean (± SD) were 26.90 ± 2.11 and 2.36 ± 0.69, respectively. In Pearson correlation analysis, BMI had a good correlation with AMR (r = 0.56, p = 0.000), and AMR (r = - 0.37, p = 0.001, HSS-post score; r = - 0.43, p = 0.000, KSS total-post score) had better correlations with PROMS postoperatively compared with BMI (r = - 0.27, p = 0.019, HSS-post score; r = - 0.33, p = 0.003, KSS total-post score). In multivariate linear regression analysis, AMR was negatively correlated with KSS total-post score as well as HSS-post score, while BMI was not. As for patients with complications, AMR values were between the 3rd quartile and 4th quartile of the AMR value in the entire study cohort.

CONCLUSIONS

In this study, the new obesity evaluation indicator-AMR, which was well related with BMI, was found to be a predictor of PROMS (KSS total-post score and HSS-post score) in elderly OA patients following TKA.

Sex differences in circulating leptin as a marker of adiposity in obese or overweight adolescents with type 1 diabetes

INTRODUCTION

We aimed to test whether the serum adipokines leptin and adiponectin are more strongly associated with body fat percentage (BF%) than body mass index (BMI) in adolescents with type 1 diabetes (T1D) and overweight/obesity.

RESEARCH DESIGN AND METHODS

We studied all participants in the T1D Exchange Metformin Study (n=122, median age 12.9 years, range 12-19.5; 32% males; 77% non-Hispanic whites, 100% overweight or obesity; median diabetes duration 6.7 years, range 1.4-15) with a baseline serum sample where we measured leptin and adiponectin concentrations. Anthropometric, clinical, laboratory and dual-energy X-ray absorptiometry (DEXA) scan measurements were analyzed. We compared correlation coefficients between variables of interest.

RESULTS

BF% by DEXA was significantly correlated with BMI Z-score (r=0.38, p<0.0001), BMI per cent of the 95th percentile (BMI%95) (r=0.45, p<0.0001), waist circumference (r=0.46, p<0.0001), leptin (r=0.58, p<0.00001) and leptin/adiponectin ratio (r=0.36, p<0.0001), while it was not significantly correlated with absolute body weight, adiponectin or insulin dose (total or basal). BF% was significantly more strongly correlated with leptin than with BMI Z-score in the overall group (p=0.022). However, there were sex-based differences. Among the significant correlations in the overall group, BF% was most strongly associated with leptin (r=0.75) in boys (n=39) but with waist circumference (r=0.58) in girls (n=83) (all p<0.0001).

CONCLUSIONS

Serum leptin could be used as a surrogate convenient marker of adiposity in overweight/obese adolescent boys with T1D, equivalent to BMI Z-score or BMI%95. In girls, waist circumference was the best performing marker overall, and was also strongly correlated with %BF in boys.

Sex Differences in the Relationship Between Childhood Self-Regulation and Adolescent Adiposity

OBJECTIVE

Research suggests that higher childhood self-regulation (CSR) predicts lower adiposity in adolescence. However, it is unclear whether this relationship differs by sex or by baseline weight status. Thus, this study investigated these questions in a longitudinal, community-based cohort.

METHODS

The cohort included 221 girls and 214 boys. At age 9, CSR was assessed via parent/teacher reports of effortful control, and childhood BMI z scores (BMIz) were calculated from staff measurements. Late-adolescent waist-to-height ratio was based on staff measurements at age 18.

RESULTS

CSR has a small inverse correlation with concurrent childhood BMIz in girls, but not in boys. Prospectively, however, CSR has a small inverse association with late-adolescent weight-to-height ratio in both sexes, after adjusting for childhood BMIz and other childhood predictors. This prospective association is marginally stronger for girls with higher (vs. lower) childhood BMIz.

CONCLUSIONS

CSR inversely predicts changes in adiposity across adolescence in both sexes, with some evidence that this association is stronger for girls with higher (vs. lower) childhood adiposity. However, this inverse association between CSR and adiposity may emerge earlier in girls. Future research should examine the causal status of CSR and its relationship to behaviors (e.g., diet).

Obesity, osteoporosis and bone metabolism

Obesity and osteoporosis have become major global health problems over the last decades as their prevalence is increasing. The interaction between obesity and bone metabolism is complex and not fully understood. Historically, obesity was thought to be protective against osteoporosis;however, several studies have challenged this belief. Even though the majority of the studies suggest that obesity has a favourable effect on bone density, it is unclear what the effect of obesity is on skeletal microarchitecture. Additionally, the effects of obesity on skeletal strength might be site-dependent as obese individuals are at higher risk of certain fractures. Several mechanical, biochemical and hormonal mechanisms have been proposed to explain the association between the adipose tissue and bone. Mechanical loading has positive effects on bone health, but this may not suffice in obesity. Low-grade systemic inflammation is probably harmful to the bone and increased bone marrow adipogenesis may lead to decreased bone mass in obese individuals. Finally, visceral abdominal fat may exert different actions to the bone compared with the subcutaneous fat. Achieving a better understanding of the association between adipose and bone tissue may help to identify new molecular therapeutic targets that will promote osteoblastic activity and/or inhibit adipogenesis and osteoclastic activity.

Diagnostic performance of body mass index in detection of obesity using different cutoff points for excess body fat

OBJECTIVES

The aim of this study was to assess the diagnostic sensitivity of body mass index (BMI) in detecting obesity according to different cutoff points in order to classify a high body fat percentage (%BF) in adolescents and young adults.

METHODS

This was a cross-sectional study conducted with 2447 adolescents 18 and 19 y of age residing in São Luís, Brazil and 951 young adults 21 to 23 y of age residing in Ribeirão Preto, Brazil. Three references were used to define a high %BF (i.e., those of Williams et al., Ramírez-Vélez et al., and Macias et al.). The area under the receiver operating characteristic area under the curve (AUC) was used to assess the performance of BMI.

RESULTS

Sensitivity ranged from 38.3% to 54.1% among boys and from 12.7% to 72.7% among girls. Among young adults, it ranged from 52.3% to 67.1% in men and from 33.7% to 86.6% in women. The AUC ranged from 0.69 to 0.76 among boys, from 0.56 from 0.85 among girls, from 0.75 to 0.80 among men, and from 0.67 to 0.88 among women. The best cutoff points for the BMI were 24.79 to 25.10 kg/m² for boys, 21.89 to 27.04 kg/m² for girls, 26.43 to 28.22 kg/m² for men, and 23.34 to 29.28 kg/m² for women.

CONCLUSION

The use of different references for the classification of a high %BF implied a difference in the diagnostic sensitivity of the BMI. Higher cutoff points resulted in greater sensitivity and ability to differentiate individuals with and without obesity.

Distinct phenotypic characteristics of normal-weight adults at risk of developing cardiovascular and metabolic diseases

BACKGROUND

The normal-weight BMI range (18.5-24.9 kg/m2) includes adults with body shape and cardiometabolic disease risk features of excess adiposity, although a distinct phenotype developed on a large and diverse sample is lacking.

OBJECTIVE

To identify demographic, behavioral, body composition, and health-risk biomarker characteristics of people in the normal-weight BMI range who are at increased risk of developing cardiovascular and metabolic diseases based on body shape.

METHODS

Six nationally representative waist circumference index (WCI, weight/height0.5) prediction formulas, with BMI and age as covariates, were developed using data from 17,359 non-Hispanic (NH) white, NH black, and Mexican-American NHANES 1999-2006 participants. These equations were then used to predict WCI in 5594 NHANES participants whose BMI was within the normal weight range. Men and women in each race/Hispanic-origin group were then separated into high, medium, and low tertiles based on the difference (residual) between measured and predicted WCI. Characteristics were compared across tertiles; P values for significance were adjusted for multiple comparisons.

RESULTS

Men and women in the high WCI residual tertile, relative to their BMI and age-equivalent counterparts in the low tertile, had significantly lower activity levels; higher percent trunk and total body fat (e.g. NH white men, X ± SE, 25.3 ± 0.2% compared with 20.4 ± 0.2%); lower percent appendicular lean mass (skeletal muscle) and bone mineral content; and higher plasma insulin and triglycerides, higher homeostatic model assessment of insulin resistance (e.g. NH white men, 1.45 ± 0.07 compared with 1.08 ± 0.06), and lower plasma HDL cholesterol. Percent leg fat was also significantly higher in men but lower in women. Similar patterns of variable statistical significance were present within sex and race/ethnic groups.

CONCLUSIONS

Cardiometabolic disease risk related to body shape in people who are normal weight according to BMI is characterized by a distinct phenotype that includes potentially modifiable behavioral health risk factors.

Body Fat Distribution, Overweight, and Cardiac Structures in School-Age Children: A Population-Based Cardiac Magnetic Resonance Imaging Study

Background

Adiposity is associated with larger left ventricular mass in children and adults. The role of body fat distribution in these associations is not clear. We examined the associations of body fat distribution and overweight with cardiac measures obtained by cardiac magnetic resonance imaging in school‐age children.

Methods and Results

In a population‐based cohort study including 2836 children, 10 years of age, we used anthropometric measures, dual‐energy X‐ray absorptiometry, and magnetic resonance imaging to collect information on body mass index, lean mass index, fat mass index, and abdominal visceral adipose tissue index. Indexes were standardized by height. Cardiac measures included right and left ventricular end‐diastolic volume, left ventricular mass, and mass‐to‐volume ratio as a marker for concentricity. All body fat measures were positively associated with right and left ventricular end‐diastolic volumes and left ventricular mass, with the strongest associations for lean mass index (all P<0.05). Obese children had a 1.12 standard deviation score (95% CI, 0.94–1.30) larger left ventricular mass and a 0.35 standard deviation score (95% CI, 0.14–0.57) higher left ventricular mass‐to‐volume ratio than normal weight children. Conditional on body mass index, higher lean mass index was associated with higher right and left ventricular end‐diastolic volume and left ventricular mass, whereas higher fat mass measures were inversely associated with these cardiac measures (all P<0.05).

Conclusions

Higher childhood body mass index is associated with a larger right and left ventricular size. This association is influenced by higher lean mass. In childhood, lean mass may be a stronger determinant of heart growth than fat mass. Fat mass may influence cardiac structures at older ages.

Associations of air pollution with obesity and body fat percentage, and modification by polygenic risk score for BMI in the UK Biobank

Air pollution has consistently been associated with cardiometabolic outcomes, although associations with obesity have only been recently reported. Studies of air pollution and adiposity have mostly relied on body mass index (BMI) rather than body fat percentage (BF%), and most have not accounted for noise as a possible confounder. Additionally, it is unknown whether genetic predisposition for obesity increases susceptibility to the obesogenic effects of air pollution. To help fill these gaps, we used the UK Biobank, a large, prospective cohort study in the United Kingdom, to explore the relationship between air pollution and adiposity, and modification by a polygenic risk score for BMI. We used 2010 annual averages of air pollution estimates from land use regression (NO₂, NO_X, PM_2.5, PM_{2.5absorbance}, PM_2.5-10, PM₁₀), traffic intensity (TI), inverse distance to road (IDTR), along with examiner-measured BMI, waist-hip-ratio (WHR), and impedance measures of BF%, which were collected at enrollment (2006-2010, n = 473,026) and at follow-up (2012-2013, n = 19,518). We estimated associations of air pollution with BMI, WHR, and BF% at enrollment and follow-up, and with obesity, abdominal obesity, and BF%-obesity at enrollment and follow-up. We used linear and logistic regression and controlled for noise and other covariates. We also assessed interactions of air pollution with a polygenic risk score for BMI. On average, participants at enrollment were 56 years of age, 54% were female, and 32% had completed college or a higher degree. Almost all participants (~95%) were white. All air pollution measures except IDTR were positively associated with at least one continuous measure of adiposity at enrollment. However, NO₂ was negatively associated with BMI but positively associated with WHR at enrollment, and IDTR was also negatively associated with BMI. At follow-up (controlling for enrollment adiposity), we observed positive associations for PM_2.5-10 with BMI, PM₁₀ with BF%, and TI with BF% and BMI. Associations were similar for binary measures of adiposity, with minor differences for some pollutants. Associations of NO_X, NO₂, PM_{2.5absorbance}, PM_2.5 and PM₁₀, with BMI at enrollment, but not at follow-up, were stronger among individuals with higher BMI polygenic risk scores (interaction p <0.05). In this large, prospective cohort, air pollution was associated with several measures of adiposity at enrollment and follow-up, and associations with adiposity at enrollment were modified by a polygenic risk score for obesity.

Relationship between the plasma acylcarnitine profile and cardiometabolic risk factors in adults diagnosed with cardiovascular diseases

The development of cardiovascular diseases (CVDs) is often asymptomatic. Identification of initial indicators of cardiometabolic disruption may assist in its early detection. The objective was to determine the relationships between plasma acylcarnitines (ACs) and cardiometabolic risk factors in adults with and without CVDs. The AC profile in human plasma of healthy controls [non-CVD group, n = 13)] and individuals diagnosed with CVDs (CVD group, n = 34) were compared. A targeted analysis of 29 ACs was performed using flow injection analysis-tandem mass spectrometry. There were significant direct correlations (p < 0.05) between ACs and cardiometabolic risk factors. Comparing the groups after adjustment for covariates, showed that the ACs that were best differentiated (p < 0.05) between the two groups and that presented "good" diagnostic accuracy were carnitine [30.7 (25.5-37.7) vs. 37.7 (32.3-45.0) µM], the short-chain ACs: acetylcarnitine [8.9 (7.4-10.2) vs. 11.9 (9.2-14.4) µM] and isovalerylcarnitine [0.10 (0.06-0.13) vs. 0.13 (0.10-0.16) µM], and the medium-chain ACs: hexanoylcarnitine [0.04 (0.03-0.05) vs. 0.06 (0.05-0.07) µM] and decenoylcarnitine [0.18 (0.12-0.22) vs. 0.22 (0.17-0.32) µM]. This assessment contributes to the identification of the unique metabolic features exhibited in association with cardiometabolic risk in adults diagnosed with CVD. The altered metabolites have the potential to be used as biomarkers for early detection of CVD.

Predictive value of lateral soft tissue thickness for complications after total hip arthroplasty with a lateral incision

The purpose of this study was to determine the relationship between soft tissue thickness lateral to the greater trochanter, as measured on anteroposterior pelvis radiograph, and postoperative complications following primary total hip arthroplasty. A retrospective review of 1110 consecutive patients treated at a single institution from 2003 to 2011 was conducted. Postoperative complications were divided into surgical site infections, deep wound infections, noninfectious surgical complications, need for revision surgery, and medical complications. Lateral soft tissue thickness (LSTT) was measured as the horizontal distance from the most lateral point on the greater trochanter to the skin edge obtained from anteroposterior hip radiographs. Among the 1110 study patients, 19.19% had a postoperative complication, with a deep infection rate of 3.42%. Of the previously identified risk factors, increased LSTT and body mass index were both associated with surgical site infection and deep infection, and LSTT was associated with revision surgery. An LSTT value of >5 cm was predictive of surgical site infection, deep infection, and revision surgery. This easily obtainable radiographic measurement, along with clinical examination near the operative site, might prove helpful in making preoperative risk assessments.

Body composition assessment in athletes with physical impairment who have been practicing a wheelchair sport regularly and for a prolonged period

BACKGROUND

Today several important aspects related to the impact of long-term wheelchair sports on whole-body and regional body composition in athletes with a physical impairment are poorly understood.

OBJECTIVE

This cross-sectional study aimed at investigating the impact of the long-term regular practice of wheelchair sports on body composition in male wheelchair athletes (WA) as compared with both non-athletic participants with a physical impairment and non-athletic able-bodied participants.

METHODS

Nine WA were each matched pairwise by age, duration of injury and body mass index (BMI) with a participant with a physical impairment not engaged in any wheelchair sport (N-WA) and by age and BMI with an able-bodied (AB) participant. Whole-body and regional bone mineral content (BMC), fat-free soft tissue mass (FFSTM), fat mass (FM) and percentage FM (%FM) were assessed by means of Dual-Energy X-ray Absorptiometry.

RESULTS

WA had significantly lower FM and %FM vs. N-WA at the whole-body level (P = 0.01 for both) and in the trunk region (P = 0.001 and P = <0.001, respectively). The only difference in body composition variables between WA and AB was found in the legs where WA had significantly higher FM (P = 0.014) along with lower BMC (P = 0.009) and FFSTM (P = 0.005) vs. AB in the legs.

CONCLUSIONS

The results of the present study showed that the regular, long-term practice of wheelchair sport may be associated with beneficial body composition adaptations in athletes with a physical impairment at the whole-body and trunk level.

Mendelian Randomization Study of Obesity and Cerebrovascular Disease

OBJECTIVE

To systematically investigate causal relationships between obesity and cerebrovascular disease and the extent to which hypertension and hyperglycemia mediate the effect of obesity on cerebrovascular disease.

METHODS

We used summary statistics from genome-wide association studies for body mass index (BMI), waist-to-hip ratio (WHR), and multiple cerebrovascular disease phenotypes. We explored causal associations with 2-sample Mendelian randomization (MR) accounting for genetic covariation between BMI and WHR, and we assessed what proportion of the association between obesity and cerebrovascular disease was mediated by systolic blood pressure (SBP) and blood glucose levels, respectively.

RESULTS

Genetic predisposition to higher BMI did not increase the risk of cerebrovascular disease. In contrast, for each 10% increase in WHR there was a 75% increase (95% confidence interval [CI] = 44-113%) in risk for large artery ischemic stroke, a 57% (95% CI = 29-91%) increase in risk for small vessel ischemic stroke, a 197% increase (95% CI = 59-457%) in risk of intracerebral hemorrhage, and an increase in white matter hyperintensity volume (β = 0.11, 95% CI = 0.01-0.21). These WHR associations persisted after adjusting for genetic determinants of BMI. Approximately one-tenth of the observed effect of WHR was mediated by SBP for ischemic stroke (proportion mediated: 12%, 95% CI = 4-20%), but no evidence of mediation was found for average blood glucose.

INTERPRETATION

Abdominal adiposity may trigger causal pathological processes, partially independent from blood pressure and totally independent from glucose levels, that lead to cerebrovascular disease. Potential targets of these pathological processes could represent novel therapeutic opportunities for stroke. ANN NEUROL 2020;87:516-524.

A new anthropometric index to predict percent body fat in young adults

OBJECTIVE

To propose a new anthropometric index that can be employed to better predict percent body fat (PBF) among young adults and to compare with current anthropometric indices.

DESIGN

Cross-sectional.

SETTING

All measurements were taken in a controlled laboratory setting in Seoul (South Korea), between 1 December 2015 and 30 June 2016.

PARTICIPANTS

Eighty-seven young adults (18-35 years) who underwent dual-energy x-ray absorptiometry (DXA) were used for analysis. Multiple regression analyses were conducted to develop a body fat index (BFI) using simple demographic and anthropometric information. Correlations of DXA measured PBF (DXA_PBF) with previously developed anthropometric indices and the BFI were analysed. Receiver operating characteristic curve analyses were conducted to compare the ability of anthropometric indices to identify obese individuals.

RESULTS

BFI showed a strong correlation with DXA_PBF (r = 0·84), which was higher than the correlations of DXA_PBF with the traditional (waist circumference, r = 0·49; waist to height ratio, r = 0·68; BMI, r = 0·36) and alternate anthropometric indices (a body shape index, r = 0·47; body roundness index, r = 0·68; body adiposity index, r = 0·70). Moreover, the BFI showed higher accuracy at identifying obese individuals (area under the curve (AUC) = 0·91), compared with the other anthropometric indices (AUC = 0·71-0·86).

CONCLUSIONS

The BFI can accurately predict DXA_PBF in young adults, using simple demographic and anthropometric information that are commonly available in research and clinical settings. However, larger representative studies are required to build on our findings.

Despite Low Obesity Rates, Body Mass Index Under-Estimated Obesity among Russian Police Officers When Compared to Body Fat Percentage

In some countries, obesity rates among police officers are higher than the general public, despite physically demanding jobs. Obesity rates based on body mass index (BMI) may lack accuracy as BMI does not directly address body composition. Since data are lacking for obesity rates among Russian police officers, this study documented and compared officer obesity rates to the adult Russian population and compared the accuracy of body mass index (BMI) for obesity classification to two direct measures of body composition. Moscow region police officers (N = 182, 84% men) underwent height, weight, waist circumference (WC), and body fat percentage (BF%) bioelectrical impedance measurements during annual medical examinations. BMI-defined obesity rates were 4.6% for men and 17.2% for women, which were >3 and >1.8 times lower than Russian adults, respectively. WC-defined obesity rates were similar to BMI (3.3% for men and 10.3% for women), but BF%-defined obesity rates were much higher (22.2% for men and 55.2% for women). Although obesity rates were lower than those found among police officers in other countries, BMI alone was not a particularly accurate method for classifying weight status among Russian police officers.

Obesity-Associated Alterations of Natural Killer Cells and Immunosurveillance of Cancer

Obesity is accompanied by a systemic chronic low-grade inflammation as well as dysfunctions of several innate and adaptive immune cells. Recent findings emphasize an impaired functionality and phenotype of natural killer (NK) cells under obese conditions. This review provides a detailed overview on research related to overweight and obesity with a particular focus on NK cells. We discuss obesity-associated alterations in subsets, distribution, phenotype, cytotoxicity, cytokine secretion, and signaling cascades of NK cells investigated in vitro as well as in animal and human studies. In addition, we provide recent insights into the effects of physical activity and obesity-associated nutritional factors as well as the reduction of body weight and fat mass on NK cell functions of obese individuals. Finally, we highlight the impact of impaired NK cell physiology on obesity-associated diseases, focusing on the elevated susceptibility for viral infections and increased risk for cancer development and impaired treatment response.

Nutritional status and outcomes of superficial femoral artery stenting due to intermittent claudication

BACKGROUND

The pathogenesis of in-stent restenosis is still not clear. The aim of this study was to determine the nutritional status of patients with lower limb ischemia and the risk of target lesion revascularization (TLR) after superficial femoral artery (SFA) stenting.

METHODS

Numerous parameters of nutritional status assessment were compared between 70 patients undergoing SFA endovascular intervention with a self-expandable plane stent due to life-limiting intermittent claudication and 40 patients undergoing carotid artery stenting (CAS). All subjects were followed up for at least 1 year in relation to outcomes such as clinically driven TLR occurrence.

RESULTS

Patients undergoing SFA stenting had a lower prevalence of overweight and obesity than those who underwent CAS (51.43% vs. 72.50%; P=0.031). An increase in Ankle-Brachial Index of >0.15 after SFA stenting (early end-point) was positively associated with greater handgrip strength (HGS), fat-free mass, skeletal muscle mass and waist-to-hip ratio. Freedom from TLR (late end-point) was significantly related to a higher waist-to-height ratio (WHtR), HGS and Geriatric Nutritional Risk Index (GNRI) Score. The 1-year risk of TLR for patients with a WHtR of ≥61.39 amounted to odds ratio; 95% confidence interval: 0.21; 0.05-0.25; P=0.021.

CONCLUSIONS

Parameters of nutritional status assessment were associated with early and late outcomes of SFA stenting in patients with intermittent claudication. Abdominal fat distribution and higher HGS and GNRI scores lowered the 1-year risk of TLR. Further study is needed to determine the pathomechanism of the obesity paradox, sarcopenia and undernutrition in relation to outcomes of endovascular interventions.

Adiposity and Endometriosis Severity and Typology

STUDY OBJECTIVE

Prior research has collectively shown that endometriosis is inversely related to women's adiposity. The aim of this study was to assess whether this inverse relationship holds true by disease severity and typology.

DESIGN

Cross-sectional study among women with no prior diagnosis of endometriosis.

SETTING

Fourteen clinical centers in Salt Lake City, UT, and San Francisco, CA.

PATIENTS

A total of 495 women (of which 473 were analyzed), aged 18-44 years, were enrolled in the operative cohort of the Endometriosis, Natural History, Diagnosis, and Outcomes (ENDO) Study.

INTERVENTIONS

Gynecologic laparoscopy/laparotomy regardless of clinical indication.

MEASUREMENTS AND MAIN RESULTS

Participants underwent anthropometric assessments, body composition measurements, and evaluations of body fat distribution ratios before surgery. Surgeons completed a standardized operative report immediately after surgery to capture revised American Society for Reproductive Medicine staging (I-IV) and typology of disease (superficial endometriosis [SE], ovarian endometrioma [OE], and deep infiltrating endometriosis [DIE]). Linear mixed models, taking into account within-clinical-center correlation, were used to generate least square means (95% confidence intervals) to assess differences in adiposity measures by endometriosis stage (no endometriosis, I-IV) and typology (no endometriosis, SE, DIE, OE, OE + DIE) adjusting for age, race/ethnicity, and parity. Although most confidence intervals were wide and overlapping, 3 general impressions emerged: (1) women with incident endometriosis had the lowest anthropometric/body composition indicators compared with those without incident endometriosis, (2) women with stage I or IV endometriosis had lower indicators compared with women with stage II or III, and (3) women with OE and/or DIE tended to have the lowest indicators, whereas women with SE had the highest indicators.

CONCLUSION

Our research highlights that the relationship between women's adiposity and endometriosis severity and typology may be more complicated than prior research indicates.

Classification Accuracy of Body Mass Index for Excessive Body Fatness in Kuwaiti Adolescent Girls and Young Adult Women

PURPOSE

Adolescent obesity, as defined by BMI, is amongst the highest in the world in Kuwait. This study aimed to determine the extent to which BMI might be underestimating obesity as defined by excessive fatness in Kuwaiti female adolescents and young adults.

METHODS

A total of 400 apparently healthy Kuwaiti female university students (mean age 18.0 years, SD 0.6) were recruited. Excessive fatness was defined as body fat percentage ≥30, measured using the Tanita model TBF-310 Bio-impedance system with the manufacturer's equation. Obesity was defined as recommended by the WHO in adult participants - those aged ≥19.1 years - as BMI≥30 kg/m². In the adolescent participants (age <19.1 years) obesity was defined as recommended by the WHO as a BMI-for-age Z score of ≥2.00. The accuracy of BMI-defined obesity to identify excessively fat individuals was determined by estimating the prevalence of obesity using high BMI and prevalence of excessive fatness, and by calculating sensitivity and specificity and predictive values.

RESULTS

Median BMI was 27.8 kg/m² (range 15.1-51.2) and median body fat percentage was 32.0 (range 5.0-54.0). The prevalence of excessive fatness was 62% (247/400 individuals were excessively fat), while the prevalence of obesity according to BMI was 42% (169/400 individuals were obese according to their BMI). The sensitivity of BMI to identify the excessively fat individuals was moderate (66%) but specificity was high (96%). The positive predictive value of BMI was 96% and the negative predictive value was 64%.

CONCLUSION

BMI-based measures substantially underestimate the prevalence of excessive fatness in Kuwaiti adolescent females. Obesity is even more prevalent, and requires more urgent attention, than is apparent from BMI-based measures used in most research and national surveys. BMI may also be too crude for use as an exposure or outcome variable in many epidemiological studies of Arab adolescent girls and adult women.

Overweight and Obesity Coexist with Thinness among Lao's Urban Area Adolescents

INTRODUCTION

In recent decades, the developing countries of Southeast Asia, including the Lao People's Democratic Republic (Lao PDR), have experienced a rapid growth of their urban population. Partly as a result of that, issues of undernutrition and overnutrition became a significant public health problem.

OBJECTIVE

To examine the prevalence of overweight and obesity and their related factors, among the school-attending adolescents in the Lao capital of Vientiane.

METHODS

A cross-sectional data on 300 adolescents aged 15-19 were collected during the months of March, April, and May 2018 by means of a self-administrated questionnaire. Anthropometric measurements were used to obtain data on height and weight. Pearson's chi-squared test, Fisher exact tests, and univariable and multivariable logistic regressions were applied in the course of the statistical analysis.

RESULTS

The study found a high prevalence of overweight/obesity (23.3%) and thinness (10.3%). Poor eating habits were noted in 67.0% of adolescents, even though 78.0% of them had a good knowledge of nutrition. Factors significantly associated with the overweight/obesity were low physical activities (aOR = 18.3; 95% CI: 5.51-60.66) and adolescents living with their guardians (aOR = 0.25; 95% CI: 0.08-0.79). Results also indicated that, in 47.3% of the cases, teachers, acting as a source of health and nutrition information, can prevent the risk of adolescents' overweight/obesity (aOR = 2.05, 95% CI = 1.11-3.80) but not their thinness (aOR = 0.4, 95% CI = 0.17-0.88).

CONCLUSIONS

Laotian adolescents are facing the spectrum of malnutrition in urban areas. To improve adolescents' nutritional status, there is a need for a collaborative approach of public health agencies that would address the issues of an effective food and nutrition policy. The school curricula should also include programs on nutrition and physical education.

A Machine Learning Approach to Short-Term Body Weight Prediction in a Dietary Intervention Program

Weight and obesity management is one of the emerging challenges in current health management. Nutrient-gene interactions in human obesity (NUGENOB) seek to find various solutions to challenges posed by obesity and over-weight. This research was based on utilising a dietary intervention method as a means of addressing the problem of managing obesity and overweight. The dietary intervention program was done for a period of ten weeks. Traditional statistical techniques have been utilised in analyzing the potential gains in weight and diet intervention programs. This work investigates the applicability of machine learning to improve on the prediction of body weight in a dietary intervention program. Models that were utilised include Dynamic model, Machine Learning models (Linear regression, Support vector machine (SVM), Random Forest (RF), Artificial Neural Networks (ANN)). The performance of these estimation models was compared based on evaluation metrics like RMSE, MAE and R2. The results indicate that the Machine learning models (ANN and RF) perform better than the other models in predicting body weight at the end of the dietary intervention program.