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

Project STARLIT: protocol of a longitudinal study of habitual sleep trajectories, weight gain, and obesity risk behaviors in college students

BACKGROUND

Obesity in the United States is a serious and preventable health concern. Previous research suggests that habitual short sleep may influence obesity-risk behaviors, such as increased caloric intake, decreased physical activity and increased engagement in sedentary activities (e.g., media consumption, computer usage). Given that existing longitudinal research studies have methodological concerns preventing conclusive interpretations, Project STARLIT was designed to address these limitations and identify future intervention targets.

METHODS

A sample of young adults (n = 300) will be recruited during the summer prior to entering college. Participants will be screened for eligibility requirements prior to the inclusion in the Time 1 assessment though phone and in-person interviews. Once enrolled, participants will complete four assessments over a two year period (i.e., approximately 8, 16 and 24 months after Time 1). Each assessment will consist of one week of data collection including both objective (i.e., habitual sleep, physical activity, body fat composition) and subjective (i.e., sleep diary, 24-h food recall, technology use, and sleep-related beliefs/behaviors) measures.

DISCUSSION

Project STARLIT is designed to address methodological concerns of previous research. In addition to clarifying the relationship between habitual short sleep and weight gain among young adults, the proposed study will identify problematic obesity risk behaviors associated with habitual short sleep (e.g., increased caloric intake, physical/sedentary activity). The results will identify prevention or intervention targets related to obesity risk.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04100967, 9/23/19, Retrospectively registered.

Adipose tissue quantification and primary graft dysfunction after lung transplantation: The Lung Transplant Body Composition study

BACKGROUND

Obesity is associated with an increased risk of primary graft dysfunction (PGD) after lung transplantation. The contribution of specific adipose tissue depots is unknown.

METHODS

We performed a prospective cohort study of adult lung transplant recipients at 4 U.S. transplant centers. We measured cross-sectional areas of subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) on chest and abdominal computed tomography (CT) scans and indexed each measurement to height.2 We used logistic regression to examine the associations of adipose indices and adipose classes with grade 3 PGD at 48 or 72 hours, and Cox proportional hazards models to examine survival. We used latent class analyses to identify the patterns of adipose distribution. We examined the associations of adipose indices with plasma biomarkers of obesity and PGD.

RESULTS

A total of 262 and 117 subjects had available chest CT scans and underwent protocol abdominal CT scans, respectively. In the adjusted models, a greater abdominal SAT index was associated with an increased risk of PGD (odds ratio 1.9, 95% CI 1.02-3.4, p = 0.04) but not with survival time. VAT indices were not associated with PGD risk or survival time. A greater abdominal SAT index correlated with greater pre- and post-transplant leptin (r = 0.61, p < 0.001, and r = 0.44, p < 0.001), pre-transplant IL-1RA (r = 0.25, p = 0.04), and post-transplant ICAM-1 (r = 0.25, p = 0.04). We identified 3 latent patterns of adiposity. The class defined by high thoracic and abdominal SAT had the greatest risk of PGD.

CONCLUSIONS

Subcutaneous, but not visceral, adiposity is associated with an increased risk of PGD after lung transplantation.

Efficacy of verum and sham acupoint catgut embedding for treatment of obesity: Study protocol for a randomized controlled trial

Background

Obesity has become a major public health hazard with epidemic proportions, affecting adults, adolescents, and children of both genders. Previous studies have suggested that acupoint catgut embedding (ACE) might be a potential therapeutic approach for obesity. The purpose of this study is to conduct a rigorous and normative trial to determine the efficacy of ACE for obesity.

Methods/design

A total of 99 eligible patients diagnosed with obesity will be recruited in this study. They will be randomly allocated to either the verum ACE group, sham ACE group, or waiting list (WL) group, with 33 patients in each group. Each patient in the two ACE-based groups will receive eight sessions of treatment, lasting over 8 weeks. The primary outcome is the reduction of body mass index (BMI) after treatment. Secondary outcomes will include waist circumference (WC), hip circumference (HC), waist:hip ratio, body fat percentage, blood lipid level, subcutaneous fat area, visceral fat area, and World Health Organization Quality of Life (WHOQOL). All the outcomes will be evaluated at baseline, at the end of the 8 weeks of treatments, and at 3 months of follow-up. The evaluators and data analyzers will be blinded to group allocation.

Discussion

The findings of this randomized, sham-, and WL-controlled trial will help to investigate the influence of ACE on clinical variables as well as visceral fat area of obesity, which will provide high-quality evidence on the efficacy of ACE for obesity.

Trial registration

Chinese Clinical Trial Registry, ChiCTR1800020248. Registered on December 21, 2018.

Obesity and 1-Year Mortality in Adults After Sepsis: A Systematic Review

PURPOSE

In recent years, researchers have noted an "obesity paradox," where individuals with obesity survive sepsis at higher rates than their nonobese counterparts. This systematic review summarizes the literature on studies examining the association between obesity and 1-year mortality among patients admitted with sepsis, severe sepsis, or septic shock.

MATERIALS AND METHODS

Using a comprehensive search strategy, a systematic review was conducted to identify studies examining the association of obesity and sepsis mortality. PubMed, Cumulative Index of Nursing and Allied Health Literature, and Elton B. Stephens Company host databases were searched for the terms sepsis, obesity, mortality, and adult.

RESULTS

The initial search identified 189 studies, 9 of which met inclusion criteria. Of these, four provided evidence that obese or very obese patients with sepsis have lower mortality than nonobese patients. Methodologic differences in the remaining five studies, which reported conflicting results, limit generalizability.

CONCLUSION

This systematic review on the association of obesity and sepsis mortality found three studies that demonstrated lower sepsis mortality among obese patients in the first 30 days and one showing that this protective effect extends up to 1 year. Given the increased number of patients surviving sepsis, it is important to consider long-term mortality and further describe the variables associated with increased survival.

Vascular Dysfunction among Malaysian Men with Increased BMI: An Indication of Synergistic Effect of Free Testosterone and Inflammation

Background and objectives: Obesity is associated with poor vascular function and may lead to future cardiovascular disease (CVD). Obesity is also related to increased inflammation and a low testosterone level. This study was conducted to determine the relationship between inflammation, testosterone level, and vascular function among subjects with an increased body mass index (BMI) and to determine whether both low testosterone and high inflammation have synergistic effects towards vascular dysfunction. Materials and Methods: A total of 303 men aged 40-80 years were recruited from Klang Valley, Malaysia. Their height, weight, blood pressure (BP), lipid, blood glucose level, total testosterone (TT), free testosterone (FT), and C-reactive protein (CRP) were measured. The carotid femoral pulse wave velocity (PWVCF) and augmentation index (AI) were also recorded as markers of vascular function. Results: The mean age of all the subjects was 54.46 ± 9.77 years. Subjects were divided into a low/normal body mass index (BMI) group (BMI < 25 kg/m2; NG, n = 154) and high BMI group (BMI ≥ 25 kg/m2; OG, n = 149). The mean BMI for NG was 22.20 ± 1.94 kg/m2 while for OG was 28.87 ± 3.24 kg/m2 (p < 0.01). The level of TT (OG = 21.13 ± 6.44 versus NG = 16.18 ± 6.16 nmol/L, p < 0.01) and FT (OG = 0.34 ± 0.12 versus NG = 0.39 ± 0.11 nmol/L, p < 0.01) were reduced while the level of CRP [OG = 1.05 (2.80) versus NG = 0.50 (1.50) mmol/L, p = 0.01] was increased in OG compared to NG. PWVCF (OG = 8.55 ± 1.34 versus NG = 8.52 ± 1.42 m/s, p = 0.02) and AI (OG = 16.91% ± 6.00% versus 15.88% ± 5.58%, p < 0.01) were significantly increased in OG after adjustment for other CVD risk factors. The subjects that had both a low FT and an increased CRP had higher AI when compared to those with a high CRP and high FT (p < 0.01). Conclusions: The increased BMI was associated with vascular dysfunction, mediated by a low testosterone level and increased inflammation. Furthermore, having both conditions concurrently lead to higher vascular dysfunction. Weight loss, testosterone supplementation, and the anti-inflammatory agent may be beneficial for men to prevent vascular dysfunction.

Is There Enough Evidence for Osteosarcopenic Obesity as a Distinct Entity? A Critical Literature Review

The co-existence of impaired bone health (osteopenia/osteoporosis), reduced muscle mass and strength (sarcopenia), and increased adiposity (obesity) in middle-aged and older people has been identified in recent studies, leading to a proposal for the existence of "osteosarcopenic obesity" as a distinct entity. Evidence for the pathophysiological overlap of these conditions is mounting, although a causal relationship is yet to be established. Each component condition occurs frequently with increasing age, and with shared risk factors in many instances, thus, an overlap of these three conditions is not surprising. However, whether the concurrent existence of sarcopenia, osteoporosis and obesity leads to an increased risk of adverse musculoskeletal outcomes and mortality above and beyond the risks associated with the sum of the component parts remains to be proven and is a question of research interest. In this article, we review evidence for the existence of osteosarcopenic obesity including the current operational definition of osteosarcopenic obesity, prevalence, pathophysiology, outcomes and exploratory approaches to the management of components. We conclude that, there is insufficient evidence to support a discrete clinical entity of osteosarcopenic obesity at this time. To expand knowledge and understanding in this area, there is a need for consensus on a definition of osteosarcopenic obesity which will allow for identification, further epidemiological studies and comparisons between studies. Additionally, studies should assess whether the clinical outcomes associated with osteosarcopenic obesity are worse than the mere addition of those linked with its components. This will help to determine whether defining a person as having this triad will eventually result in a more effective treatment than addressing each of the three conditions separately.

Significant Associations Between Sun Exposure and Adiposity Were Not Observed in Breast and Prostate Cancer Patients in a Cross-sectional Analysis

Obesity is a significant health problem worldwide. Exposure to low-dose ultraviolet radiation (like that in sunlight) suppresses the development of obesity in mice; however, the nature of the associations between sun exposure and adiposity is not well understood in humans. The present study characterized cross-sectional relationships between sun exposure and adiposity in a convenience cohort of breast (n = 269; mean age = 58 years) and prostate (n = 78; mean age = 69 years) cancer patients. Participants were enrolled in a 3-month exercise program in Perth, Australia. Self-reported questionnaires measured time spent outdoors (previous week, winter and summer), sex, age, treatment received and physical activity levels. Adiposity measures included body mass index, waist-hip ratio and body fat percentage (measured via DXA). In unadjusted models, greater time spent outdoors across all times was significantly associated with lower waist-hip ratio, while greater time spent outdoors in the last winter was associated with lower body fat percentage, but not when stratified by sex. There were no statistically significant associations between time spent outdoors and adiposity after adjusting for sex, age, treatments received and physical activity. Longitudinal studies in larger populations may elucidate significant associations not found in our study due to the cross-sectional design and power limitations.

Associations of cardiometabolic outcomes with indices of obesity in children aged 5 years and younger

BACKGROUND

Childhood obesity is a world-wide concern due to its growing prevalence and association with cardiometabolic risk factors in childhood and subsequent adult cardiovascular disease. In young pre-school children, there is uncertainty regarding which of the commonly used anthropometric measures of childhood obesity is best associated with cardiometabolic risk factors. This study compared the utility of common measures used in identifying obesity in these young children.

METHODS

The four commonly used metrics for identifying obesity in children: body fat percentage ≥ 90th percentile, waist circumference ≥ 90th percentile, BMI z score > 2 SD and waist-to-height ratio (WHtR) ≥ 0.5, were measured in a cohort of children born singleton, at full term and followed from birth (n = 761) to 5 years of age (n = 513). The utility of each in identifying cardiometabolic risk factors (fasting lipid profile, fasting blood glucose and blood pressure) was examined.

RESULTS

At age 5 years, children with percent body fat ≥ 90th percentile or waist circumference ≥ 90th percentile, were associated with higher levels of triglycerides, glucose, and systolic and diastolic blood pressures than those < 90th percentile, respectively. Such differences were not obvious at age 3 years or at birth. A BMI z-score > 2 SD was associated with higher levels of triglycerides and systolic and diastolic blood pressure but not glucose at age 5 years. Differences in HDL cholesterol, fasting glucose and systolic blood pressure were observed in children with BMI z score > 2 SD at age 3 years but not with the other indices of obesity. As almost all children had WHtR ≥ 0.5 at birth, ages 1 and 3 years, this measure could not differentiate increased cardiometabolic risk. At age 5 years, the differences were much more obvious, with significant differences in triglycerides and systolic and diastolic blood pressures between those with WHtR ≥ 0.5 and those with < 0.5.

CONCLUSION

Each of the four commonly used measures of childhood obesity shows moderate associations with cardiometabolic risk factors at 5 years, with no advantage of one measure over the other. These associations were less consistent at 3 years of age or younger. These observations have not been reported previously.

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.

Food portion size influences accompanying beverage selection in adults

When trying to reduce food portion size, it is important that meal satisfaction is, as far as possible, preserved. Otherwise, individuals may select accompaniments to the meal (e.g., snacks, beverages) to achieve satisfaction and, in doing so, negate any benefit of the original portion size reduction. This study investigated whether varying portion sizes of food would influence choice of accompanying beverages. That is, when presented with a food portion size that is smaller or larger than their ideal, an individual may compensate by choosing a beverage based on its satiating and/or orosensory properties to balance the expected satiation and satisfaction of a meal. Data from an online interactive study (n = 93) was analysed using multilevel ordinal logistic regression models. Food portion size (100, 300, 500, 700, or 900 kcal) predicted beverage choice (water, low-energy sweetened beverage, high-energy sweetened beverage). For example, the sweetened beverages were more likely to be selected with small food portion sizes (p < .001). Participant ideal food portion size did not interact with this relationship. Participants appear to have recognised that sweetened beverages provide flavour and/or energy, and used them to compensate for a smaller meal. While switching to a low-energy beverage with an increased food portion size is advantageous for energy balance, choosing a high-energy beverage with a decreased food portion size is likely to be detrimental for those attempting to reduce energy intake and body weight.

Body Fat Percentage, Waist Circumference, and Obesity As Risk Factors for Rheumatoid Arthritis: A Danish Cohort Study

OBJECTIVE

To investigate the relationship between bioimpedance-derived total body fat percentage, waist circumference, and body mass index (BMI) and the subsequent development of rheumatoid arthritis (RA).

METHODS

A population-based prospective cohort study was conducted using 55,037 patients enrolled in the Danish Diet, Cancer, and Health cohort. Baseline data included anthropometric measures and lifestyle factors. Individuals who developed RA were identified through linkage with the Danish National Patient Registry. The relationships between bioimpedance-derived body fat percentage, waist circumference, and BMI and incident RA were assessed using Cox proportional hazards regression models, stratifying by sex. All analyses were performed for overall RA and the serologic subtypes seropositive and other RA.

RESULTS

A total of 210 men (37.6% with seropositive RA) and 456 women (41.0% with seropositive RA) developed RA during a median follow-up of 20.1 years. In women, the overall RA risk was 10% higher for each 5% increment of total body fat (hazard ratio [HR] 1.10 [95% confidence interval (95% CI) 1.02-1.18]), 5% higher for each 5-cm increment of waist circumference (HR 1.05 [95% CI 1.01-1.10]), and nearly 50% higher in those whose BMI was in the obese range compared to normal range BMI (HR 1.46 [95% CI 1.12-1.90]). These positive associations were also found for patients with other RA. In men, there were no clear associations between body fat percentage, waist circumference, or BMI and RA. No significant associations were found for seropositive RA in women or men, possibly related to low sample size.

CONCLUSION

In women, higher body fat percentage, higher waist circumference, and obesity were associated with a higher risk of RA.

Efficacy of weight loss intervention can be predicted based on early alterations of fMRI food cue reactivity in the striatum

Increased fMRI food cue reactivity in obesity, i.e. higher responses to high- vs. low-calorie food images, is a promising marker of the dysregulated brain reward system underlying enhanced susceptibility to obesogenic environmental cues. Recently, it has also been shown that weight loss interventions might affect fMRI food cue reactivity and that there is a close association between the alteration of cue reactivity and the outcome of the intervention. Here we tested whether fMRI food cue reactivity could be used as a marker of diet-induced early changes of neural processing in the striatum that are predictive of the outcome of the weight loss intervention. To this end we investigated the relationship between food cue reactivity in the striatum measured one month after the onset of the weight loss program and weight changes obtained at the end of the six-month intervention. We observed a significant correlation between BMI change measured after six months and early alterations of fMRI food cue reactivity in the striatum, including the bilateral putamen, right pallidum, and left caudate. Our findings provide evidence for diet-induced early alterations of fMRI food cue reactivity in the striatum that can predict the outcome of the weight loss intervention.

Impact of obesity on breast cancer recurrence and minimal residual disease

BACKGROUND

Obesity is associated with an increased risk of breast cancer recurrence and cancer death. Recurrent cancers arise from the pool of residual tumor cells, or minimal residual disease (MRD), that survives primary treatment and persists in the host. Whether the association of obesity with recurrence risk is causal is unknown, and the impact of obesity on MRD and breast cancer recurrence has not been reported in humans or in animal models.

METHODS

Doxycycline-inducible primary mammary tumors were generated in intact MMTV-rtTA;TetO-HER2/neu (MTB/TAN) mice or orthotopic recipients fed a high-fat diet (HFD; 60% kcal from fat) or a control low-fat diet (LFD; 10% kcal from fat). Following oncogene downregulation and tumor regression, mice were followed for clinical recurrence. Body weight was measured twice weekly and used to segregate HFD mice into obese (i.e., responders) and lean (i.e., nonresponders) study arms, and obesity was correlated with body fat percentage, glucose tolerance (measured using intraperitoneal glucose tolerance tests), serum biomarkers (measured by enzyme-linked immunosorbent assay), and tissue transcriptomics (assessed by RNA sequencing). MRD was quantified by droplet digital PCR.

RESULTS

HFD-Obese mice weighed significantly more than HFD-Lean and LFD control mice (p < 0.001) and had increased body fat percentage (p < 0.001). Obese mice exhibited fasting hyperglycemia, hyperinsulinemia, and impaired glucose tolerance, as well as decreased serum levels of adiponectin and increased levels of leptin, resistin, and insulin-like growth factor 1. Tumor recurrence was accelerated in HFD-Obese mice compared with HFD-Lean and LFD control mice (median relapse-free survival 53.0 days vs. 87.0 days vs. 80.0 days, log-rank p < 0.001; HFD-Obese compared with HFD-Lean HR 2.52, 95% CI 1.52-4.16; HFD-Obese compared with LFD HR 2.27, 95% CI 1.42-3.63). HFD-Obese mice harbored a significantly greater number of residual tumor cells than HFD-Lean and LFD mice (12,550 ± 991 vs. 7339 ± 2182 vs. 4793 ± 1618 cells, p < 0.001).

CONCLUSION

These studies provide a genetically engineered mouse model for study of the association of diet-induced obesity with breast cancer recurrence. They demonstrate that this model recapitulates physiological changes characteristic of obese patients, establish that the association between obesity and recurrence risk is causal in nature, and suggest that obesity is associated with the increased survival and persistence of residual tumor cells.

Adipose-to-muscle area ratio at the knee is superior to BMI in predicting post-operative outcome following arthroscopic meniscectomy

PURPOSE

To determine if measurement of leg adipose tissue area by MRI is a better predictor of post-operative clinical outcome compared to body mass index (BMI) following arthroscopic meniscectomy.

METHODS

Patients that underwent an arthroscopic partial meniscectomy between 2011 and 2016 were identified and a retrospective chart review was performed. Patients with additional knee pathology other than a meniscal tear with or without associated articular cartilage injury were excluded. Leg adipose tissue and muscle area measurements at the level of the knee joint were performed for patients on their preoperative axial magnetic resonance imaging (MRI) study and adipose-to-muscle area ratio (AMR) was calculated. Correlations among AMR, BMI, and post-operative clinical outcomes were compared.

RESULTS

A total of 74 patients (32 females and 42 males) were included (mean age 50.0 years, std. dev. 12.3 years). 35 patients underwent a partial medial meniscectomy, 15 underwent a partial lateral meniscectomy, and 24 underwent both. Linear regression analysis showed that the AMR, compared to BMI, had a significantly stronger correlation to both mean post-operative Knee Injury and Osteoarthritis Outcome Score (KOOS) across all 5 subscales (KOOS₅) and Tegner Current score. Patients that had cartilage damage and concurrent chondroplasty tended to be older and have lower post-operative KOOS₅ compared to those with no cartilage damage. AMR was also significantly correlated to age and BMI.

CONCLUSIONS

The current study demonstrates that compared to BMI, leg adiposity as determined by the ratio of adipose tissue to muscle area on axial MRI (AMR), is a stronger predictor of functional outcome following meniscectomy. This suggests a role of obesity in the progression of OA beyond the increased joint forces associated with increased BMI.

LEVEL OF EVIDENCE

IV, retrospective case series.

Examining validity of body mass index calculated using height and weight data from the US driver license

BACKGROUND

Driver license departments in many US states collect data on individuals' height and weight. These data can be useful to researchers in epidemiological and public health studies. As height and weight on driver license are self-reported, they may be prone to reporting bias. We compare height and weight obtained from driver license records and clinically measured height and weight, as well as body mass index (BMI) values calculated using the two data sources for the same individual.

METHODS

We linked individual height and weight records obtained from the Driver License Division (DLD) in the Utah Department of Public Safety to clinical records from one of the largest healthcare providers in the state of Utah. We then calculated average differences between height, weight and BMI values separately for women and men in the sample, as well as discrepancies between the two sets of measures by age and BMI category. We examined how well self-reported height and weight from the driver licenses classify individuals into specific BMI categories based on clinical measures. Finally, we used two sets of BMI values to estimate individuals' relative risk of type II diabetes.

RESULTS

Individuals, on average, tend to overestimate their height and underestimate their weight. Consequently, the value of BMI calculated using driver license records is lower than BMI calculated using clinical measurements. The discrepancy varies by age and by BMI category. Despite the discrepancy, BMI based on self-reported height and weight allows for accurate categorization of individuals at the higher end of the BMI scale, such as the obese. When used as predictors of relative risk of type II diabetes, both sets of BMI values yield similar risk estimates.

CONCLUSIONS

Data on height and weight from driver license data can be a useful asset for monitoring population health in states where such information is collected, despite the degree of misreporting associated with self-report.

An observational study of perioperative nutrition and postoperative outcomes in patients undergoing laparotomy at Queen Elizabeth Central Hospital in Blantyre, Malawi

Background

Nutritional status in patients undergoing surgery can influence their immune function, tissue repair and, hence, clinical outcomes. This study aimed to assess the perioperative nutrition and postoperative outcome of patients undergoing laparotomy at a tertiary hospital in Malawi.

Methods

A total of 25 patients were included in this prospective, observational study. The Subjective Global Assessment was used to classify each patient according to nutritional status. Handgrip strength was measured for each patient preoperatively and at day 3 postoperatively. Anthropometric measurements were also done. Protein and energy requirements for each participant were estimated and compared to the quantities provided by the hospital diet. Patients were followed up until discharge and outcome variables which included length of hospital stay and wound dehiscence or infectious complications were recorded.

Results

Of the study participants, 20% were well-nourished, 52% were moderately malnourished and 28% were severely malnourished. The median handgrip strength decreased at day 3 postoperatively from the preoperative handgrip strength. Well-nourished patients had higher handgrip strength than malnourished patients both preoperatively and postoperatively. Total energy and protein provided by the hospital diet were significantly lower than the estimated requirements for the patients. Severely malnourished patients had increased median length of hospital stay and increased rate of postoperative complications. Preoperative and postoperative day 3 handgrip strength correlated negatively with the number of postoperative complications and length of hospital stay.

Conclusion

This study showed high rates of malnutrition and inadequate in-hospital nutritional support which were associated with poor clinical outcomes, especially in severely malnourished patients. Proper nutritional assessment and provision of adequate nutritional support should be reinforced in surgical patients to promote favourable clinical outcomes postoperatively. Further studies with larger sample sizes in other patient populations and hospitals in Malawi are required in this area.

Waist circumference, waist-to-height ratio and conicity index to evaluate android fat excess in Brazilian children

OBJECTIVE

To evaluate the ability of anthropometric measurements to identify excess android fat and to propose cut-off points for excess central adiposity in children, according to age and sex.

DESIGN

A cross-sectional study with children from a municipality of Minas Gerais, Brazil. Receiver-operating characteristic curve analyses were performed to evaluate waist circumference (WC), waist-to-height ratio (WHtR) and conicity index (C-index) in estimating excess android fat by dual energy X-ray absorptiometry (DXA).

SETTING

Viçosa, Minas Gerais, Brazil.

SUBJECTS

Children aged 4-9 years (n 788).

RESULTS

Overweight prevalence was 29·1 % and android fat percentage was higher among girls. All central fat measurements were able to discriminate excess android fat in the age groups evaluated, especially WC and WHtR, with cut-off points showing good sensitivity and specificity overall.

CONCLUSIONS

Because these methods are easy to obtain and inexpensive, it is possible to use WC, WHtR and C-index in population surveys to evaluate central obesity. The proposed cut-off points showed satisfactory values of sensitivity and specificity and can be used in epidemiological studies.

Dietary source of saturated fat and percentage body fat of patients with type 2 diabetes mellitus: A cross-sectional study

BACKGROUND

The influence of dietary fat on the body fat of patients with diabetes is not well established. This cross-sectional study aimed to analyze the association between percentage body fat (PBF) and dietary sources of fat from the usual diet of patients with type 2 diabetes.

METHODS

Outpatients were submitted to PBF evaluation estimated by bioelectrical impedance. The patient's usual diet was assessed by a 3-day weighed diet record (WDR), and compliance was analyzed by comparing the protein intake estimated from the WDR and that from 24-hr urinary nitrogen output.

RESULTS

A total of 188 patients with type 2 diabetes (aged 62.5 ± 8.8 years; 57% female, body mass index [BMI] 29.3 ± 3.8 kg/m²) were analyzed and divided into groups with high and low PBF according to mean PBF (men: 26.6 ± 7.1%; women: 39.8 ± 5.9%). Patients with high PBF consumed an increased proportion of red meat (52.0% of total meat), processed meat (5.4%), and saturated fat from red meat (2.1% of energy) compared to low PBF individuals (42.3% [p = 0.036]; 3.0% [p = 0.010]; 1.5% of energy [p = 0.032], respectively). According to Poisson's regression, the consumption of red meat (PR = 1.008 [95% CI = 1.002-1.013]; p = 0.006) and the reuse of frying oil (PR = 1.670 [95% CI = 1.240-2.249]; p = 0.001) were associated with higher PBF. In the adjusted analysis, the upper tertile of processed meat intake was associated with higher PBF (PR = 1.522 [95% CI = 1.226-1.891]; p = 0.001) compared to the lower tertile.

CONCLUSIONS

The present study suggested that a higher ingestion of dietary sources of saturated fat was associated with high PBF in patients with type 2 diabetes.

Drug-naive patients with schizophrenia have metabolic disorders that are not associated with polymorphisms in the LEP (-2548G/A) and 5-HTR2C (-759C/T) genes

Schizophrenia is a mental disorder that is primarily caused by polygenic mutations. Schizophrenic patients are more likely to suffer from metabolic syndrome (MS), which is usually accompanied by polymorphisms in the leptin (LEP) gene at the -2548 (G/A) locus and the 5-hydroxytryptamine receptor 2C (5-HTR2C) gene at the -759 (C/T) locus. Hence, we hypothesized an association between these polymorphisms and schizophrenia incidence. A total of 148 drug-naive schizophrenic patients and 165 normal controls were enrolled in the study. Blood glucose levels, lipid levels, and other metabolic markers were measured. MALDI-TOFMS was performed to analyse genotypes of LEP and 5-HTR2C at -2548 (G/A) and -759 (C/T) loci, respectively. Patients with first-episode schizophrenia showed higher levels of fasting blood glucose and the 2-h postprandial glucose (2 hPG), as well as higher insulin resistance indices, but showed lower high-density lipoprotein cholesterol (HDL-C) levels compared to those of the controls. The above results were partly observed when the analysis was performed separately in males and females. Schizophrenic and healthy participants showed no significant differences in the genotypes and allele frequencies in the leptin and 5-HTR2C genes. Patients with varying genotypes of -2548 (G/A) in the leptin gene and -759 (C/T) in the 5-HTR2C gene showed no differences in the indices related to the glucose and lipid metabolism. Taken together, drug-naive schizophrenia patients showed some incidence of metabolic disorders, but polymorphisms in the LEP (-2548G/A) and 5-HTR2C (-759C/T) genes were not associated with schizophrenia or metabolic disorders.

Development and validation of two anthropometric models estimating abdominal fat percentage in Greek adult women and men

BACKGROUND AND AIMS

Abdominal obesity is associated with adverse health implications. However, the assessment of abdominal adiposity is either indirect, like in the case of waist circumference measurement, or difficult in daily clinical practice, like in the case of using reference methods such as computerized tomography, magnetic resonance imaging, etc. The aim of the current study was to develop and validate, using DXA as reference method, two easy and simple to use protocols, that estimate abdominal fat mass percentage (%AFM) in Greek females and males respectively, based on simple anthropometric measurements.

METHODS

Circumferences and skinfolds were obtained from 709 Caucasian adults (437 women and 272 men) in order to develop and validate the two equations. The validation and the reliability of the equations were examined with Bland-Altman analysis and Intraclass Correlation Coefficient (ICC).

RESULTS

The equations were: for females, %AFM = -121,368 - (17,322 × Height(m)) + (76,452 × log Abdominal Circumference(cm)) + (18,341 × log Suprailiac Skinfold(mm)) + (8802 × log Abdominal Skinfold(mm)), for males, %AFM = -174,117 - (15,247 × Height(m))+ (104,503 × log Abdominal Circumference(cm)) + (9907 × log Suprailiac Skinfold(mm)) + (7971 × log Abdominal Skinfold(mm)). The equations had no significant bias (0,203% and 0,406%, respectively), acceptable limits of agreement (±9.358% and ±8.780%, respectively) and high reliability (0,940 and 0,957, respectively).

CONCLUSION

Both equations were found to be valid and reliable for Greek population. Therefore, the utilization of these equations for abdominal fat assessment could be an alternative of labor-intensive, expensive and time-consuming reference methods.

Sex and body weight are major determinants of venlafaxine pharmacokinetics

We assessed the effect of body weight and BMI on plasma concentrations of venlafaxine (VEN), O-desmethylvenlafaxine (ODVEN), active moiety (AM=VEN+ODVEN), and dose-corrected plasma concentrations (C/D). A database containing concentrations of VEN and ODVEN including 737 of 1594 eligible patients was analyzed. Analyses included sex, body weight, and BMI as well as concentrations of VEN, ODVEN, AM, and C/D. A positive correlation was detected between body weight and daily dosage (rs=0.168, P<0.001). A negative correlation was found between body weight and AM (rs=-0.124, P=0.001) and ODVEN (rs=-0.137, P<0.001). Negative correlations were also found between body weight and C/D ratios (C/D VEN: rs=-0.134, P<0.001, C/D ODVEN: rs=-0.239, P<0.001, C/D AM: rs=-0.256, P<0.001). No correlations were detected between BMI and concentrations for VEN, ODVEN, and AM. Comparing low-BMI (<20 kg/m²), medium-BMI (20-29.9 kg/m²), and high-BMI (≥30 kg/m²) groups, higher values of some pharmacokinetic variables in the lower BMI group did not remain significant after controlling for sex. Women had higher VEN, ODVEN, AM, and C/D values for AM, VEN, and ODVEN than men (P<0.001 for all comparisons). Our results highlight the role of different pharmacokinetically relevant parameters and foremost of sex as mediators for the effect of BMI on VEN metabolism.

Obesity in the global haemophilia population: prevalence, implications and expert opinions for weight management

Overweight and obesity may carry a significant disease burden for patients with haemophilia (PWH), who experience reduced mobility due to joint inflammation, muscle dysfunction and haemophilic arthropathy. This review aimed to define the prevalence and clinical impact of overweight/obesity in the global population of PWH. A detailed literature search pertaining to overweight/obesity in haemophilia in the last 15 years (2003-2018) was conducted, followed by a meta-analysis of epidemiological data. The estimated pooled prevalence of overweight/obesity in European and North American PWH was 31%. Excess weight in PWH is associated with a decreased range in motion of joints, accelerated loss of joint mobility and increase in chronic pain. Additionally, the cumulative disease burden of obesity and haemophilia may impact the requirement for joint surgery, occurrence of perioperative complications and the prevalence of anxiety and depression that associates with chronic illness. Best practice guidelines for obesity prevention and weight management, based on multidisciplinary expert perspectives, are considered for adult and paediatric PWH. Recommendations in the haemophilia context emphasize the importance of patient education and tailoring engagement in physical activity to avoid the risk of traumatic bleeding.

Methylation of imprinted IGF2 regions is associated with total, visceral, and hepatic adiposity in postmenopausal women

Excess body fat, especially intra-abdominal fat, is a leading risk factor for metabolic diseases. Differentially methylated regions (DMRs) of two imprinted genes, insulin-like growth factor 2 (IGF2) and H19, have been associated with obesity due to their important roles in regulating body composition, but have not been examined in relation to intra-abdominal fat depots. Total body fat from whole-body dual energy X-ray absorptiometry and visceral and liver fat contents from abdominal magnetic resonance imaging in 48 healthy women aged 60-65 years (of White or Japanese ancestry) were each regressed on circulating leukocyte DNA methylation levels of IGF2 (at DMR0, DMR2a, and DMR2b) and H19 (at CTCF3) as assessed by pyrosequencing, while adjusting for age and race/ethnicity. Total fat mass was inversely associated with methylation levels of IGF2 DMR2b (P = 0.016). Total fat-adjusted visceral fat area (P = 0.062) and percent visceral fat measured at L4-L5 (P = 0.045) were associated with higher methylation levels of IGF2 DMR2b. Both total fat-adjusted percent liver fat (P = 0.039) and the presence of fatty liver (P = 0.015) were positively associated with IGF2 DMR2a methylation. Methylation levels of H19 CTCF3 were not associated with overall or intra/abdominal adiposity. The findings indicate that methylation levels of IGF2 DMR regions in leukocytes are associated with total body fat and with fat distribution in the viscera and liver independently of total adiposity.

Prediction equations for body composition of children and adolescents aged 8-19 years in Uganda using deuterium dilution as the reference technique

BACKGROUND AND AIMS

Body composition is important as a marker of both current and future health status. Bioelectrical impedance analysis (BIA) is a simple and accurate method for estimating body composition in field, clinical and research settings, if standard protocol procedures are followed. However, BIA requires population-specific equations since applicability of existing equations to diverse populations has been questioned. This study aimed to derive predictive equations for Total Body Water (TBW), Fat Free Mass (FFM) and Fat Mass (FM) determinations with BIA and anthropometric measurements in a population of children and adolescents aged 8-19 years in Uganda.

METHODS

A cross-sectional study was conducted among 203 children and adolescents aged 8-19 years attending schools in Kampala district (also referred to as Kampala city since the city is conterminous with the district), Uganda through a two-stage cluster sample design. Deuterium dilution method (DDM) was used as the reference measure while BIA and anthropometric measures were used to create the new body composition prediction equations through multivariate regression.

RESULTS

The new prediction equations explained 88%, 87% and 71% of the variance in TBW, FFM % and of FM respectively with no statistical shrinkage upon cross-validation. The linear regression models proposed in this study were well adjusted with respect to TBW, FFM and FM. Log of TBW obtained by DDM = 0.0129 × Impedance index + 0.0055 × Age + 0.0049 Waist Circumference + 0.1219Ht² + 2.0388. Log of FFM obtained by DDM = 0.0197 × FFM obtained by BIA - 0.0181 sex code - 0.00055 × Impedance + 3.1761. Log of FM obtained by DDM = 0.0634 × FM obtained by BIA - 0.1881 sex code + 0.0252 × Weight + 0.5273.

CONCLUSION

The use of these equations for more accurate body composition assessment may facilitate identification of effective intervention strategies to prevent or combat overweight and obesity among children and adolescents. They may also assist in treatment of conditions where more accurate information on body composition measures is required.

Lipid phenotyping of lung epithelial lining fluid in healthy human volunteers

BACKGROUND

Lung epithelial lining fluid (ELF)-sampled through sputum induction-is a medium rich in cells, proteins and lipids. However, despite its key role in maintaining lung function, homeostasis and defences, the composition and biology of ELF, especially in respect of lipids, remain incompletely understood.

OBJECTIVES

To characterise the induced sputum lipidome of healthy adult individuals, and to examine associations between different ELF lipid phenotypes and the demographic characteristics within the study cohort.

METHODS

Induced sputum samples were obtained from 41 healthy non-smoking adults, and their lipid compositions analysed using a combination of untargeted shotgun and liquid chromatography mass spectrometry methods. Topological data analysis (TDA) was used to group subjects with comparable sputum lipidomes in order to identify distinct ELF phenotypes.

RESULTS

The induced sputum lipidome was diverse, comprising a range of different molecular classes, including at least 75 glycerophospholipids, 13 sphingolipids, 5 sterol lipids and 12 neutral glycerolipids. TDA identified two distinct phenotypes differentiated by a higher total lipid content and specific enrichments of diacyl-glycerophosphocholines, -inositols and -glycerols in one group, with enrichments of sterols, glycolipids and sphingolipids in the other. Subjects presenting the lipid-rich ELF phenotype also had significantly higher BMI, but did not differ in respect of other demographic characteristics such as age or gender.

CONCLUSIONS

We provide the first evidence that the ELF lipidome varies significantly between healthy individuals and propose that such differences are related to weight status, highlighting the potential impact of (over)nutrition on lung lipid metabolism.

Stratified Probabilistic Bias Analysis for Body Mass Index-related Exposure Misclassification in Postmenopausal Women

BACKGROUND

There is widespread concern about the use of body mass index (BMI) to define obesity status in postmenopausal women because it may not accurately represent an individual's true obesity status. The objective of the present study is to examine and adjust for exposure misclassification bias from using an indirect measure of obesity (BMI) compared with a direct measure of obesity (percent body fat).

METHODS

We used data from postmenopausal non-Hispanic black and non-Hispanic white women in the Women's Health Initiative (n=126,459). Within the Women's Health Initiative, a sample of 11,018 women were invited to participate in a sub-study involving dual-energy x-ray absorptiometry scans. We examined indices of validity comparing BMI-defined obesity (≥30 kg/m), with obesity defined by percent body fat. We then used probabilistic bias analysis models stratified by age and race to explore the effect of exposure misclassification on the obesity-mortality relationship.

RESULTS

Validation analyses highlight that using a BMI cutpoint of 30 kg/m to define obesity in postmenopausal women is associated with poor validity. There were notable differences in sensitivity by age and race. Results from the stratified bias analysis demonstrated that failing to adjust for exposure misclassification bias results in attenuated estimates of the obesity-mortality relationship. For example, in non-Hispanic white women 50-59 years of age, the conventional risk difference was 0.017 (95% confidence interval = 0.01, 0.023) and the bias-adjusted risk difference was 0.035 (95% simulation interval = 0.028, 0.043).

CONCLUSIONS

These results demonstrate the importance of using quantitative bias analysis techniques to account for nondifferential exposure misclassification of BMI-defined obesity. See video abstract at, http://links.lww.com/EDE/B385.

Complications of pelvic and acetabular fractures in 1331 morbidly obese patients (BMI ≥ 40): a retrospective observational study from the National Trauma Data Bank

Background

There have been no large-scale epidemiological studies of outcomes and perioperative complications in morbidly obese trauma patients who have sustained closed pelvic ring or acetabular fractures. We examined this population and compared their rate of inpatient complications with that of control patients.

Methods

We retrospectively reviewed the records of patients treated for closed pelvic ring or acetabular fracture, aged 16–85 years, with Injury Severity Scores ≤15 from the National Trauma Data Bank Research Dataset for the years 2007 through 2010. The primary outcome of interest was rate of in-hospital complications. Secondary outcomes were length of hospital stay and discharge disposition. Unadjusted differences in complication rates were evaluated using Student t tests and Chi-squared analyses. Multiple logistic and Poisson regression were used to analyze binary outcomes and length of hospital stay, respectively, adjusting for several variables. Statistical significance was defined as p < 0.05.

Results

We included 46,450 patients in our study. Of these patients, 1331 (3%) were morbidly obese (body mass index ≥40) and 45,119 (97%) were used as controls. Morbidly obese patients had significantly higher odds of complication and longer hospital stay in all groups considered except those with pelvic fractures that were treated operatively. In all groups, morbidly obese patients were more likely to be discharged to a skilled nursing/rehabilitation facility compared with control patients.

Conclusions

Morbidly obese patients had higher rates of complications and longer hospital stays and were more likely to be discharged to rehabilitation facilities compared with control patients after pelvic ring or acetabular fracture.

Obesity and mortality after locoregional breast cancer diagnosis

PURPOSE

Higher mortality after a breast cancer diagnosis has been observed among women who are obese. We investigated the relationships between body mass index (BMI) and all-cause or breast cancer-specific mortality after a diagnosis of locoregional breast cancer.

METHODS

Women diagnosed in 2004 with AJCC Stage I, II, or III breast cancer (n = 5394) were identified from a population-based National Program of Cancer Registries (NPCR) patterns of care study (POC-BP) drawing from registries in seven U.S. states. Differences in overall and breast cancer-specific mortality were investigated using Cox proportional hazards regression models adjusting for demographic and clinical covariates, including age- and stage-based subgroup analyses.

RESULTS

In women 70 or older, higher BMI was associated with lower overall mortality (HR for a 5 kg/m² difference in BMI = 0.85, 95% CI 0.75-0.95). There was no significant association between BMI and overall mortality for women under 70. BMI was not associated with breast cancer death in the full sample, but among women with Stage I disease; those in the highest BMI category had significantly higher breast cancer mortality (HR for BMI ≥ 35 kg/m² vs. 18.5-24.9 kg/m² = 4.74, 95% CI 1.78-12.59).

CONCLUSIONS

Contrary to our hypothesis, greater BMI was not associated with higher overall mortality. Among older women, BMI was inversely related to overall mortality, with a null association among younger women. Higher BMI was associated with breast cancer mortality among women with Stage I disease, but not among women with more advanced disease.

CD4+ and CD8+ T-Cell-Specific DNA Cytosine Methylation Differences Associated With Obesity

OBJECTIVE

Lifestyle factors associated with obesity may alter epigenome-regulated gene expression. Most studies examining epigenetic changes in obesity have analyzed DNA 5´-methylcytosine (5mC) in whole blood, representing a weighted average of several distantly related and regulated leukocyte classes. To examine leukocyte-specific differences associated with obesity, a pilot study examining 5mC in three distinct leukocyte types isolated from peripheral blood of women with normal weight and obesity was conducted.

METHODS

CD4⁺ T cells, CD8⁺ T cells, and CD16⁺ neutrophils were reiteratively isolated from blood, and 5mC levels were measured across >450,000 CG sites.

RESULTS

Nineteen CG sites were differentially methylated between women with obesity and with normal weight in CD4⁺ cells, 16 CG sites in CD8⁺ cells, and 0 CG sites in CD16⁺ neutrophils (q < 0.05). There were no common differentially methylated sites between the T-cell types. The amount of visceral adipose tissue was strongly associated with the methylation level of 79 CG sites in CD4⁺ cells, including 4 CG sites in CLSTN1's promoter, which, this study shows, may regulate its expression.

CONCLUSIONS

The methylomes of various leukocytes respond differently to obesity and levels of visceral adipose tissue. Highly significant differentially methylated sites in CD4⁺ and CD8⁺ cells in women with obesity that have apparent biological relevance to obesity were identified.

In BMI We Trust: Reframing the Body Mass Index as a Measure of Health

Recent work in medical sociology has provided critical insights into distinguishing between obesity as a condition with severe individual- and population-level health consequences, and obesity as a socially undesirable, stigmatizing construct opposing thinness as the healthy ideal. Less often considered is the role of Body Mass Index (BMI) as the standard by which obesity and healthy weight are measured and defined. Addressing this issue, I begin by distinguishing between BMI as an empirical, objective measure of health, and BMI as an arbitrary, subjective label for categorizing the population. I further consider how BMI is empowered as a measurable quantity through the lens of medicalization and evidence-based medicine, and introduce the "performativity" of BMI as a superior framework for confronting the measure's conceptual limitations. Emphasizing key parallels between BMI and self-rated health as measures with high predictive validity, yet unspecified mechanisms of action, I propose an epistemological shift away from classifying BMI as a biomarker and toward a more flexible view of the measure as a holistic appraisal of health. In closing, I argue that researchers may continue to leverage BMI's ease of collection and interpretation, provided they are attuned to its definitional ambiguity across diverse research methods and contexts.

Ecological momentary assessment of food perceptions and eating behavior using a novel phone application in adults with or without obesity

We developed a smart phone application to measure participants' food-reward perceptions and eating behavior in their naturalistic environment. Intensity ratings (0 - not at all to 10 - very strongly) of perceived anticipation of food (wanting) and food enjoyment at endpoint of intake (liking) were recorded as they occurred over a period of 14 days. Moreover, food craving trait, implicit and explicit attitude towards healthy food, and body composition were assessed. 53 participants provided complete data. Participants were classified by percentage of body fat; 33 participants with lower body fat (L-group) and 20 with higher body fat (H-group; ≥25% body fat for males and ≥32% for females). L-group participants reported 6.34 (2.00) food wanting events per day, whereas H-group participants recorded significantly fewer food wanting events (5.07 (1.42)); both groups resisted about the same percentage of wanting events (L-group: 29.2 (15.5)%; H-group 27.3 (12.8)%). Perceived intensity ratings were significantly different within the L-group in the order liking (7.65 (0.81)) > un-resisted wanting (leading to eating) (7.00 (1.01)) > resisted wanting (not leading to eating) (6.02 (1.72)) but not in the H-group. Liking scores (L-group: 7.65 (0.81); H-group: 7.14 (1.04)) were significantly higher in L-group than in H-group after controlling for age. Our results show that individuals with higher percentage of body fat show less food enjoyment after intake and reveal no differentiation in intensity ratings of perceived anticipatory and consummatory food reward. These results are consistent with a hypothesized reward deficiency among individuals with higher percentage of body fat.

Upper body fat predicts metabolic syndrome similarly in men and women

BACKGROUND

The metabolic syndrome is a constellation of risk factors including dyslipidemia, dysglycemia, hypertension, a pro-inflammatory state, and a prothrombotic state. All of these factors are accentuated by obesity. However, obesity can be defined by body mass index (BMI), percent body fat, or by body fat distribution. The latter consists of upper body fat (subcutaneous and visceral fat) and lower body fat (gluteofemoral fat). Waist circumference is a common surrogate marker for upper body fat.

METHODS

Data from the National Health and Nutrition Examination Survey (NHANES) for the years 1999-2006 was examined for associations of metabolic risk factors with percent body fat, waist circumference, and BMI.

RESULTS

Associations between absolute measures of waist circumference and risk factors were similiar for men and women. The similarities of associations between waist circumference and risk factors suggests that greater visceral fat in men does not accentuate the influence of upper body fat on risk factors.

CONCLUSIONS

Different waist concumference values should not be used to define abdominal obesity in men and women.

TRUNK BODY MASS INDEX: A NEW REFERENCE FOR THE ASSESSMENT OF BODY MASS DISTRIBUTION

BACKGROUND

Body mass index (BMI) has some limitations for nutritional diagnosis since it does not represent an accurate measure of body fat and it is unable to identify predominant fat distribution.

AIM

To develop a BMI based on the ratio of trunk mass and height.

METHODS

Fifty-seven patients in preoperative evaluation to bariatric surgery were evaluated. The preoperative anthropometric evaluation assessed weight, height and BMI. The body composition was evaluated by bioimpedance, obtaining the trunk fat free mass and fat mass, and trunk height. Trunk BMI (tBMI) was calculated by the sum of the measurements of the trunk fat free mass (tFFM) and trunk fat mass (tFM) in kg, divided by the trunk height squared (m2)). The calculation of the trunk fat BMI (tfBMI) was calculated by tFM, in kg, divided by the trunk height squared (m2)). For the correction and adjustment of the tBMI and tfBMI, it was calculated the relation between trunk extension and height, multiplying by the obtained indexes.

RESULTS

The mean data was: weight 125.3±19.5 kg, height 1.63±0.1 m, BMI was 47±5 kg/m2) and trunk height was 0.52±0,1 m, tFFM was 29.05±4,8 kg, tFM was 27.2±3.7 kg, trunk mass index was 66.6±10.3 kg/m², and trunk fat was 32.3±5.8 kg/m². In 93% of the patients there was an increase in obesity class using the tBMI. In patients with grade III obesity the tBMI reclassified to super obesity in 72% of patients and to super-super obesity in 24% of the patients.

CONCLUSION

The trunk BMI is simple and allows a new reference for the evaluation of the body mass distribution, and therefore a new reclassification of the obesity class, evidencing the severity of obesity in a more objectively way.

Determining the joint effect of obesity and diabetes on functional disability at 3-months and on all-cause mortality at 1-year following an ischemic stroke

BACKGROUND

Obesity and diabetes mellitus, or diabetes, are independently associated with post-ischemic stroke outcomes (e.g., functional disability and all-cause mortality). Although obesity and diabetes are also associated with post-ischemic stroke outcomes, the joint effect of obesity and diabetes on these post-ischemic stroke outcomes has not been explored previously. The purpose of the current study was to explore whether the effect of obesity on post-ischemic stroke outcomes differed by diabetes status in a cohort of acute ischemic stroke subjects with at least a moderate stroke severity.

METHODS

Data from the Interventional Management of Stroke (IMS) III clinical trial was analyzed for this post-hoc analysis. A total of 656 subjects were enrolled in IMS III and were followed for one year. The joint effects of obesity and diabetes on functional disability at 3-months and all-cause mortality at 1-year were examined.

RESULTS

Of 645 subjects with complete obesity and diabetes information, few were obese (25.74%) or had diabetes (22.64%). Obese subjects with diabetes and non-obese subjects without diabetes had similar odds of functional disability at 3-months following an ischemic stroke (adjusted common odds ratio, 1.038, 95% CI: 0.631, 1.706). For all-cause mortality at 1-year following an ischemic stroke, obese subjects with diabetes had a similar hazard compared with non-obese subjects without diabetes (adjusted hazard ratio, 1.005, 95% CI: 0.559, 1.808). There was insufficient evidence to declare a joint effect between obesity and diabetes on either the multiplicative scale or the additive scale for both outcomes.

CONCLUSIONS

In this post-hoc analysis of data from the IMS III clinical trial of acute ischemic stroke patients with at least a moderate stroke severity, there was not sufficient evidence to determine that the effect of obesity differed by diabetes status on post-ischemic stroke outcomes. Additionally, there was not sufficient evidence to determine that either factor was independently associated with all-cause mortality. Future studies could differentiate between metabolically healthy and metabolically unhealthy patients within BMI categories to determine if the effect of obesity on post-stroke outcomes differs by diabetes status.

Body mass index and prognosis of breast cancer: An analysis by menstruation status when breast cancer diagnosis

OBJECTIVE

To examine whether obesity/overweight is a risk predictor for breast cancer recurrence and death by menopausal status in a retrospective study.

METHODS

We performed a retrospective analysis of 1017 breast cancer patients treated in our hospital from January 2004 to December 2012. Three groups were divided according to body mass index (BMI) when breast cancer diagnosis: normal weight, BMI < 25.0 kg/m; overweight, 25.0≤BMI < 30.0 kg/m; and obesity, BMI≥30.0 kg/m. The clinicopathological characteristics and clinical outcomes of patients within 5 years following breast cancer diagnosed were analyzed. Subgroup analyses of BMI on breast cancer prognosis were analyzed according to the menopausal status when breast cancer diagnosis. The Cox proportional hazards model was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

Overweight and obesity groups were associated with larger size tumors, older age, increased proportion of postmenopausal patients and less patients choosing anthracycline and/or taxane regimen. The 5-year disease-free survival (DFS) and overall survival (OS) decreased in overweight and obese patients (P < .001), and both overweight and obesity were independent predictors for increased risks of breast cancer relapse and death (P < .001). When stratified by menopausal status, both overweight and obesity were associated with reduced 5-year DFS and OS in postmenopausal patients (P < .050), and multivariate analysis showed that the risk of relapse and breast cancer mortality in these 2 groups also increased (P < .050). Among premenopausal patients, the risks of relapse and death were significantly increased in obesity group rather than overweight group by multivariate analysis.

CONCLUSION

Overweight and obesity might be independently associated with poorer prognosis for breast cancer patients, and the effects of overweight on the breast cancer prognosis seem to be related to menopausal status.

Anthropometry, Body Composition, and Performance in Sport-Specific Field Test in Female Wheelchair Basketball Players

Data on the physical and performance characteristics of female wheelchair basketball (WB) players are scarce. In several countries female WB players train and compete with male players on mixed teams due to the limited total population of players, which would otherwise lead to large territorial spread for each team. Any differences in terms of physical characteristics and/or WB skill proficiency between male and female WB players would be relevant to team performance in mixed teams. This work examined anthropometry, body composition, and performance in a set of sport-specific field tests in a sample of 13 female WB players representing about 40% of the eligible population in Italy across a range of functional point scores (Point). Point is assigned on an ordinal scale from 1.0 (i.e., players with minimal functional potential) through to 4.5 (players with maximum functional potential). Our female sample was then compared against twice as many (n = 26) Point-matched (±0.5 points) male players. The two groups were similar for age (P = 0.191; effect size [d] = 0.2), self-reported duration of injury (P = 0.144, d = 0.6), WB experience (P = 0.178, d = 0.5), and volume of training (P = 0.293, d = 0.4). The large majority of measured linear anthropometric variables (10/13) were lower in female players than males (0.001 < P ≤ 0.041). Skinfold-estimated percent body fat was higher (+7.6%) in females (30.7 ± 6.0%; P < 0.001, d = 1.3). Mean performance was worse in female than in males in six out of seven sport-specific field tests, scores being significantly lower in females for the maximal pass (7.5 ± 2.0 m for females vs. 10.4 ± 2.8 m for males; P = 0.002, d = 1.2) and suicide tests (55.8 ± 6.4 s for females vs. 45.4 ± 6.7 s for males; P < 0.001, d = 1.6). When performance in subgroups of females (n = 9) chosen across a range of Point was compared with that of males assigned 1.0 or 1.5 Point less (each n = 9), performance differences between male and female WB players were partially and completely eliminated, respectively. This work contributed new data for characterizing the physique and performance of female WB players. Further, the results suggested that when male and female athletes compete together in mixed teams, a 1.5 points subtraction from female players is needed to match the real gender difference in performance.

Peer mentor versus teacher delivery of a physical activity program on the effects of BMI and daily activity: protocol of a school-based group randomized controlled trial in Appalachia

BACKGROUND

Rural Appalachian populations have poorer health and fewer positive health-related behaviors compared to other United States populations. Appalachians are the most sedentary U.S. population and teens are particularly sedentary. Obesity prevention through improving physical activity is a top priority in Rural Healthy People 2020. Obesity prevalence among Appalachian teens exceeds the national rates of 13.9% and has consistently been greater than 26%. Organized sports has not been effective at improving daily physical activity or health outcomes for Appalachian teens. The purpose of this study is to test the efficacy of a 10-week school-based intervention in promoting self-regulation of physical activity among adolescents not participating in organized sports. By using accelerometers, our study will measure both sedentary time and planned exercise during waking hours.

METHODS

The design for this four-year study is a group-randomized controlled trial (G-RCT). We will recruit high schools in 3 waves, with 4 in Wave 1, 8 in Wave 2, and 8 in Wave 3, for a total of 20 schools. For each wave of schools, we will randomly assign half of the schools to each condition--intervention (peer-to-peer mentoring [MBA]) and comparison (teacher-led [PBA])--for a total of 10 schools in each of the two conditions by study's end. We will collect data at baseline (T₁), 3 months post intervention (T₂), and 6 months post intervention (T₃). Linear Mixed Models (LMMs) and Generalized Linear Mixed Models (GLMMs) will be used to test the main hypotheses. Power for this study was based the primary analysis comparing BMI outcomes at T₂ between the groups, adjusting for baseline BMI values.

DISCUSSION

This study provides age-appropriate lifestyle education and skill building. Peer-to-peer mentoring by local high school students and school-based tailored support strengthens sustainable behavioral change. Focusing on unique healthy-lifestyle challenges prevalent in low-resource areas such as Appalachia such as overcoming environmental, social, and psychological barriers may improve adherence to physical activity. Serving as role models, peer mentors may improve their own lifestyle behaviors, providing a dual intervention.

TRIAL REGISTRATION

NCT02329262 .

Using open source accelerometer analysis to assess physical activity and sedentary behaviour in overweight and obese adults

Background

Physical activity and sedentary behaviour are difficult to assess in overweight and obese adults. However, the use of open-source, raw accelerometer data analysis could overcome this. This study compared raw accelerometer and questionnaire-assessed moderate-to-vigorous physical activity (MVPA), walking and sedentary behaviour in normal, overweight and obese adults, and determined the effect of using different methods to categorise overweight and obesity, namely body mass index (BMI), bioelectrical impedance analysis (BIA) and waist-to-hip ratio (WHR).

Methods

One hundred twenty adults, aged 24–60 years, wore a raw, tri-axial accelerometer (Actigraph GT3X+), for 3 days and completed a physical activity questionnaire (IPAQ-S). We used open-source accelerometer analyses to estimate MVPA, walking and sedentary behaviour from a single raw accelerometer signal. Accelerometer and questionnaire-assessed measures were compared in normal, overweight and obese adults categorised using BMI, BIA and WHR.

Results

Relationships between accelerometer and questionnaire-assessed MVPA (Rs = 0.30 to 0.48) and walking (Rs = 0.43 to 0.58) were stronger in normal and overweight groups whilst sedentary behaviour were modest (Rs = 0.22 to 0.38) in normal, overweight and obese groups. The use of WHR resulted in stronger agreement between the questionnaire and accelerometer than BMI and BIA. Finally, accelerometer data showed stronger associations with BMI, BIA and WHR (Rs = 0.40 to 0.77) than questionnaire data (Rs = 0.24 to 0.37).

Conclusions

Open-source, raw accelerometer data analysis can be used to estimate MVPA, walking and sedentary behaviour from a single acceleration signal in normal, overweight and obese adults. Our data supports the use of WHR to categorise overweight and obese adults. This evidence helps researchers obtain more accurate measures of physical activity and sedentary behaviour in overweight and obese populations.

Directly measured free 25-hydroxy vitamin D levels show no evidence of vitamin D deficiency in young Swedish women with anorexia nervosa

PURPOSE

Anorexia nervosa (AN) is an eating disorder characterized by low fat mass complicated by osteoporosis. The role of circulating vitamin D in the development of bone loss in AN is unclear. Fat mass is known to be inversely associated with vitamin D levels measured as serum levels of total, protein-bound 25-hydroxyvitamin D, but the importance of directly measured, free levels of 25(OH)D has not been determined in AN. The aim of this study was to investigate vitamin D status, as assessed by serum concentrations of total and free serum 25(OH)D in patients with AN and healthy controls.

METHODS

In female AN patients (n = 20), and healthy female controls (n = 78), total 25(OH)D was measured by LC-MS/MS, and free 25(OH)D with ELISA. In patients with AN bone mineral density (BMD) was determined with DEXA.

RESULTS

There were no differences between patients and controls in total or free S-25(OH)D levels (80 ± 31 vs 72 ± 18 nmol/L, and 6.5 ± 2.5 vs 5.6 ± 1.8 pg/ml, respectively), and no association to BMD was found. In the entire group of patients and controls, both vitamin D parameters correlated with BMI, leptin, and PTH.

CONCLUSIONS

The current study did not demonstrate a vitamin D deficiency in patients with AN and our data does not support vitamin D deficiency as a contributing factor to bone loss in AN. Instead, we observed a trend toward higher vitamin D levels in AN subjects compared to controls. Measurement of free vitamin D levels did not contribute to additional information.

Impaired natural killer cell subset phenotypes in human obesity

Obesity is associated with alterations in functionality of immune cells, like macrophages and natural killer (NK) cells, leading to an increased risk for severe infections and several cancer types. This study aimed to examine immune cell populations and functional NK cell parameters focusing on NK cell subset phenotypes in normal-weight and obese humans. Therefore, peripheral blood mononuclear cells (PBMCs) were isolated from normal-weight and obese individuals and analyzed by flow cytometry. Results show no significant changes in the frequency of monocytes, B lymphocytes, or NKT cells but a significantly increased frequency of T lymphocytes in obesity. The frequency of total NK cells was unaltered, whereas the number of low cytotoxic CD56bright NK cell subset was increased, and the number of high cytotoxic CD56dim NK cell subset was decreased in obese subjects. In addition, the frequency of CD56bright NK cells expressing the activating NK cell receptor NKG2D as well as intracellular interferon (IFN)-γ was elevated in the obese study group. In contrast, the frequency of NKG2D- and IFN-γ-positive CD56dim NK cells was lower in obesity compared to normal-weight individuals. Moreover, the expression of the activation marker CD69 was decreased in NK cells, which can be attributed to a reduction of CD69-positive CD56dim NK cells in obese subjects. In conclusion, data reveal an impaired NK cell phenotype and NK cell subset alterations in obese individuals. This NK cell dysfunction might be one link to the higher cancer risk and the elevated susceptibility for viral infections in obesity.

Efficacy of an exercise intervention among children with comorbid asthma and obesity

OBJECTIVES

Children with comorbid asthma and obesity present with more severe and harder-to-control disease than asthmatic children at healthy weight. Weight loss has been shown to improve asthma symptoms, yet physical activity may be difficult due to exercise-induced bronchospasm. Children with asthma have lower exercise rates than non-asthmatics. The objective of this study was to retrospectively evaluate attrition rates and program outcome measures (Body Mass Index [BMI] and maximum oxygen consumption [VO₂max]) among asthmatic and non-asthmatic participants.

STUDY DESIGN

Clinical data were collected from the Healthy Hearts Program, a 12-week nutrition and activity intervention program for children who are overweight, obese, or at risk for heart disease and other conditions, and used for the study.

METHODS

Intervention data and demographics were obtained from medical records at the Children's Heart Center Nevada. Descriptive statistics, paired t-tests, Cox regression analysis, and analysis of covariance were conducted.

RESULTS

The mean age of this population (N = 232) was 11 years; 54% were male, 64% were Hispanic, and 37% had asthma. Median time in the program was 9 weeks, and 58% of the population completed the program. Unadjusted analyses showed significant BMI decreases in asthmatic (P = 0.002) and non-asthmatic (P = 0.001) participants and increases in cardiorespiratory function for asthmatic males and females (P = 0.003, P = 0.004) and non-asthmatic males and females (P < 0.001 for both). Asthmatic and non-asthmatic children both had improved exercise intensity (P = 0.033, P < 0.001).

CONCLUSIONS

This program is both beneficial and practical for obese children with asthma for losing weight and improving cardiorespiratory function.

Fat mass and obesity-associated gene rs9939609 polymorphism is a potential biomarker of recurrent venous thromboembolism in male but not in female patients

Multiple genetic variations have been identified in FTO (fat mass and obesity-associated) gene. Among them, FTO rs9939609 polymorphism is shown to be associated with the risk of primary venous thromboembolism (VTE). However, its role in recurrent VTE is not known. The aim of our study was to investigate the association between FTO rs9939609 polymorphism and the risk of VTE recurrence in a prospective follow-up study in both male and female patients. FTO rs9939609 polymorphism (T/A) was analyzed in the Malmö thrombophilia study (MATS, followed for ~10 years) by using TaqMan PCR. MATS patients (n = 1050) were followed from the discontinuation of anticoagulant treatment until diagnosis of VTE recurrence or the end of follow-up. A total of 126 patients (12%) had VTE recurrence during follow-up. Cox regression analyses showed that sex modified the potential effect of FTO rs9939609 polymorphism on VTE recurrence. Male patients with the AA genotype for the FTO rs9939609 polymorphism had significantly higher risk of VTE recurrence as compared to the TT or AT genotypes (univariate hazard ratio [HR] = 2.05, 95% confidence interval [CI] = 1.2-3.5, P = 0.009 and adjusted HR = 2.03, 95% CI 1.2-3.6, P = 0.013). There was no association between FTO rs9939609 polymorphism and VTE recurrence in female patients. In conclusion, our results show that FTO rs9939609 polymorphism in recurrent VTE may differ according to gender and FTO polymorphism may predict VTE recurrence in male patients.

Is BMI a valid measure of obesity in postmenopausal women?

OBJECTIVE

Body mass index (BMI) is a widely used indicator of obesity status in clinical settings and population health research. However, there are concerns about the validity of BMI as a measure of obesity in postmenopausal women. Unlike BMI, which is an indirect measure of obesity and does not distinguish lean from fat mass, dual-energy x-ray absorptiometry (DXA) provides a direct measure of body fat and is considered a gold standard of adiposity measurement. The goal of this study is to examine the validity of using BMI to identify obesity in postmenopausal women relative to total body fat percent measured by DXA scan.

METHODS

Data from 1,329 postmenopausal women participating in the Buffalo OsteoPerio Study were used in this analysis. At baseline, women ranged in age from 53 to 85 years. Obesity was defined as BMI ≥ 30 kg/m and body fat percent (BF%) greater than 35%, 38%, or 40%. We calculated sensitivity, specificity, positive predictive value, and negative predictive value to evaluate the validity of BMI-defined obesity relative BF%. We further explored the validity of BMI relative to BF% using graphical tools, such as scatterplots and receiver-operating characteristic curves. Youden's J index was used to determine the empirical optimal BMI cut-point for each level of BF% defined obesity.

RESULTS

The sensitivity of BMI-defined obesity was 32.4% for 35% body fat, 44.6% for 38% body fat, and 55.2% for 40% body fat. Corresponding specificity values were 99.3%, 97.1%, and 94.6%, respectively. The empirical optimal BMI cut-point to define obesity is 24.9 kg/m for 35% BF, 26.49 kg/m for 38% BF, and 27.05 kg/m for 40% BF according to the Youden's index.

CONCLUSIONS

Results demonstrate that a BMI cut-point of 30 kg/m does not appear to be an appropriate indicator of true obesity status in postmenopausal women. Empirical estimates of the validity of BMI from this study may be used by other investigators to account for BMI-related misclassification in older women.

Does Increased Body Mass Index Influence Outcomes After Rotator Cuff Repair?

PURPOSE

To investigate the influence of pre-existing obesity (body mass index [BMI] ≥ 30) on outcomes after rotator cuff repair surgery.

METHODS

We collected data on adult patients who underwent surgical repair for symptomatic full-thickness rotator cuff tears confirmed by imaging between 2012 and 2015. The required follow-up was 3 years. At baseline and 6, 12, 24, and 36 months, the American Shoulder and Elbow Surgeons score, Western Ontario Rotator Cuff index, and visual analog scale pain scores were collected. Complications were assessed by a chart review. Obesity was defined as BMI ≥ 30. Chi-square analysis and Student's t-test examined differences between categorical and continuous variables at baseline. Generalized estimating equations examined the effects of fixed factors on outcome variables longitudinally from baseline to 36 months.

RESULTS

Thirty-nine percent of 213 subjects were obese (mean BMI = 29.2; range, 16-48; standard deviation, 5.8). There were no statistically significant differences between obese and nonobese subjects in other baseline characteristics. When controlling for covariates, obese subjects reported no differences in Western Ontario Rotator Cuff, American Shoulder and Elbow Surgeons, or visual analog scale pain scores when compared with nonobese subjects at baseline and over 3 years from surgery. Although obese patients were more likely to have inpatient surgery, there was no difference in the incidence of postoperative complications.

CONCLUSIONS

Contrary to our hypothesis, obese participants who underwent rotator cuff repair reported no difference in functional outcome or pain scores compared with nonobese participants over 3 years. In addition, obesity was not associated with postoperative complications in this study. However, as we hypothesized, obese participants were more likely than nonobese participants to have repair in the inpatient setting.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Body fat percentage cutoffs for risk of cardiometabolic abnormalities in the Chinese adult population: a nationwide study

BACKGROUND/OBJECTIVES

The direct assessment of body fat (BF) by using simple methods might be an alternative index of obesity. We aim to investigate the optimal cutoffs of the %BF relating to metabolic disorders and cardiovascular risks in China.

SUBJECTS/METHODS

The data were from the 2007-2008 China National Diabetes and Metabolic Disorders Study. Participants with age of 20-75 years and with a BF measurement record were included. The %BF was measured using a foot-to-foot bioelectrical impedance analysis. Receiver operating characteristic curve was used to decide the optimal %BF cutoffs for predicting the risk of diabetes, hypertension, metabolic syndrome (MetS), and 10-year cardiovascular events (estimated by Framingham risk score (FRS)).

RESULTS

A total of 23,769 participants were enrolled with the mean age of 44.88 years, the male percentage of 40.59%, and the mean %BF of 25.22%. The mean %BFs of subjects who had diabetes, hypertension, metabolic syndrome, and FRS ≥ 10% were higher than those without diabetes, hypertension, metabolic syndrome, and FRS ≥ 10%, respectively. In men, the optimal %BF cutoffs for these four endpoints were 24.50%, 24.90%, 24.21%, and 22.10%, respectively. In women, they were 35.69%, 32.50%, 32.60%, and 32.31%, respectively. On the basis of the weights of these endpoints, the pooled optimal %BF cutoff was 23.67% and 32.88% in men and women, respectively.

CONCLUSIONS

We suggest the optimal foot-to-foot BIA-measured %BF cutoffs for predicting risk of cardiometabolic abnormalities to be 24% and 33% in Chinese men and women, respectively.