Accuracy of body mass index to determine obesity in women with breast cancer: An observational study of Taiwanese sample

Background

Obesity is common in women with breast cancer. The risk of obesity-induced metabolic syndrome is higher in Asians than in Caucasians. Excessive body fat accumulation has been associated with a worse prognosis. However, the most popular clinical indicator of obesity is not fat itself, but body mass index (BMI).

Objectives

The purposes of this study were to determine the consistency of BMI and body fat percentage (BF%) in determining obesity and to identify the best BMI cutoffs for identifying obesity in Taiwanese women with breast cancer.

Methods

Body fat and fat-free mass were measured by bioelectrical impedance 1 day before breast surgery for 200 women with breast cancer. BMI was calculated as weight (in kilograms) divided by height (in meters) squared.

Results

BMI and BF% were highly correlated (r = 0.91; p < 0.001). However, BMI exhibited poor sensitivity for identifying obesity (47%). The sensitivity of BMI to detect obesity was better in women over age 60. The best BMI cutoff for obesity was 22.3 kg/m² with a sensitivity and specificity of 89% (95% CI = 83-94%) and 87% (95% CI = 77-93%) respectively, and the total accuracy rate improved from 65% to 89%.

Conclusions

Using BMI to identify obesity in Taiwanese women with breast cancer requires careful attention to the diagnostic criterion chosen. The World Health Organization criterion tends to underestimate the prevalence of obesity, especially for younger women with breast cancer (under age 40).     

Association Between Direct Measures of Body Composition and Prognostic Factors in Chronic Heart Failure

OBJECTIVE: To explore the covariate-adjusted associations between body composition (percent body fat and lean body mass) and prognostic factors for mortality in patients with chronic heart failure (CHF) (nutritional status, N-terminal pro-B-type natriuretic peptide [NT-proBNP], quality of life, exercise capacity, and C-reactive protein).PATIENTS AND METHODS: Between June 2008 and July 2009, we directly measured body composition using dual energy x-ray absorptiometry in 140 patients with systolic and/or diastolic heart failure. We compared body composition and CHF prognostic factors across body fat reference ranges and body mass index (BMI) categories. Multiple linear regression models were created to examine the independent associations between body composition and CHF prognostic factors; we contrasted these with models that used BMI.RESULTS: Use of BMI misclassified body fat status in 51 patients (41%). Body mass index was correlated with both lean body mass (r=0.72) and percent body fat (r=0.67). Lean body mass significantly increased with increasing BMI but not with percent body fat. Body mass index was significantly associated with lower NT-proBNP and lower exercise capacity. In contrast, higher percent body fat was associated with a higher serum prealbumin level, lower exercise capacity, and increased C-reactive protein level; lean body mass was inversely associated with NT-proBNP and positively associated with hand-grip strength.CONCLUSION: When BMI is divided into fat and lean mass components, a higher lean body mass and/or lower fat mass is independently associated with factors that are prognostically advantageous in CHF. Body mass index may not be a good indicator of adiposity and may in fact be a better surrogate for lean body mass in this population.6MWD = 6-minute walk distance; BMI = body mass index; CHF = chronic heart failure; CRP = C-reactive protein; DEXA = dual energy x-ray absorptiometry; HRQoL = health-related quality of life; NT-proBNP = N-terminal pro-B-type natriuretic peptide; WHO = World Health OrganizationPopulation-based cohort studies have identified obesity as a major risk factor for the development of chronic heart failure (CHF).¹ In contrast, in patients with acute or stable heart failure, a higher body mass index (BMI) is strongly associated with decreased mortality.^2,3 These paradoxical observations have been referred to as reverse epidemiology^4,5 or the obesity paradox⁶ and, assuming they are valid, call into question the practice of extrapolating BMI targets derived from the general population to the CHF population.A number of potential explanations for the obesity paradox have been proposed.⁶ Because the paradox has been almost exclusively reported in studies that use BMI to classify obesity in CHF (with the exception of one study that used skinfold measurements⁷) and because BMI is an indirect measure of body fat, the paradox may be an artifactual finding that results from the use of an inaccurate surrogate for obesity. Alternatively, the obesity paradox may represent a valid finding that reflects a greater amount of favorable metabolic reserve or lower levels of circulating N-terminal pro-B-type natriuretic peptide (NT-proBNP) in obese patients compared with their normal-weight counterparts.⁸For editorial comment, see page 605Our objectives were to (1) characterize the body composition of obese, overweight, and normal-weight patients with CHF using dual energy x-ray absorptiometry (DEXA); (2) explore the covariate-adjusted associations between body composition (both body fat and lean body mass) and prognostic factors for mortality in CHF (nutritional status, NT-proBNP, health-related quality of life [HRQoL], 6-minute walk distance [6MWD], and C-reactive protein [CRP]); and (3) compare the results of covariate-adjusted models incorporating body composition with those incorporating BMI to examine differences in their association with CHF prognostic factors.     

δ-Aminolevulinate dehydratase activity in type 2 diabetic patients and its association with lipid profile and oxidative stress

Objectives

To investigate the activity of δ-Aminolevulinate dehydratase (δ-ALA-D) and its possible relationship with oxidative status, lipid profile, body mass index (BMI) in type 2 diabetics (DM2) patients.

Design and methods

δ-ALA-D activity and reactivation index, as well as markers of oxidative stress and biochemical and anthropometrics parameters were determined in DM2 patients (n = 63) and controls (n = 63).

Results

There was a decreased δ-ALA-D activity and a higher reactivation index (p < 0.05) in DM2 patients besides an elevated level of oxidative stress. Disturbances on lipid profile were related to the enzymatic activity and BMI also was correlated with oxidative level in DM2 patients (p < 0.05).

Conclusion

There is an association between oxidative stress, abnormalities on lipid profile, distribution of body fat and δ-ALA-D activity inhibition as well as the enzyme is more oxidized in the DM2 suggesting that it would be a good biomarker for assessing prejudice in chronic metabolic processes.     

Sex and body mass index correlate with Western Ontario and McMaster Universities Osteoarthritis Index and quality of life scores in knee osteoarthritis

Elbaz A, Debbi EM, Segal G, Haim A, Halperin N, Agar G, Mor A, Debi R. Sex and body mass index correlate with Western Ontario and McMaster Universities Osteoarthritis Index and quality of life scores in knee osteoarthritis.

Objective

To examine the associations of sex, body mass index (BMI), and age with knee osteoarthritis (OA) symptomatic severity.

Design

A cross-sectional retrospective analysis.

Setting

Patients completed the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaire and Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36). Data were acquired from a stored database of a private therapy center.

Participants

Patients (N=1487) with symptomatic knee OA were evaluated.

Interventions

Not applicable.

Main Outcome Measures

WOMAC questionnaire and SF-36.

Results

BMI correlated significantly with worse knee OA symptoms for all WOMAC and SF-36 subcategories (all P≤.001). Age correlated significantly with worse symptoms only for WOMAC function and SF-36 physical functioning (P=.001 and P=.009, respectively). A significant difference across BMI quintiles was found for all WOMAC and SF-36 subcategories (all P≤.01). Women showed worse knee OA symptoms in all WOMAC and SF-36 subcategories (all P≤.001). There was a significant interaction of sex by BMI in WOMAC pain and WOMAC function (P=.01 and P=.02, respectively).

Conclusions

Based on the results of this analysis, it can be concluded that women and patients with a higher BMI with knee OA are at a greater risk for worse symptoms.     

Excessive Loss of Skeletal Muscle Mass in Older Adults With Type 2 Diabetes

OBJECTIVE

A loss of skeletal muscle mass is frequently observed in older adults. The aim of the study was to investigate the impact of type 2 diabetes on the changes in body composition, with particular interest in the skeletal muscle mass.

RESEARCH DESIGN AND METHODS

We examined total body composition with dual-energy X-ray absorptiometry annually for 6 years in 2,675 older adults. We also measured mid-thigh muscle cross-sectional area (CSA) with computed tomography in year 1 and year 6. At baseline, 75-g oral glucose challenge tests were performed. Diagnosed diabetes (n = 402, 15.0%) was identified by self-report or use of hypoglycemic agents. Undiagnosed diabetes (n = 226, 8.4%) was defined by fasting plasma glucose (≥7 mmol/l) or 2-h postchallenge plasma glucose (≥11.1 mmol/l). Longitudinal regression models were fit to examine the effect of diabetes on the changes in body composition variables.

RESULTS

Older adults with either diagnosed or undiagnosed type 2 diabetes showed excessive loss of appendicular lean mass and trunk fat mass compared with nondiabetic subjects. Thigh muscle CSA declined two times faster in older women with diabetes than their nondiabetic counterparts. These findings remained significant after adjusting for age, sex, race, clinic site, baseline BMI, weight change intention, and actual weight changes over time.

CONCLUSIONS

Type 2 diabetes is associated with excessive loss of skeletal muscle and trunk fat mass in community-dwelling older adults. Older women with type 2 diabetes are at especially high risk for loss of skeletal muscle mass.Age-related loss of skeletal muscle mass or sarcopenia results in decreased skeletal muscle strength, mobility limitations, physical disability, and eventually high mortality among the elderly (1–3). However, little is known about the causes or risk factors associated with loss of skeletal muscle mass in older adults. In addition, although weight gain and accumulation of abdominal fat have been known as strong risk factors for the development of type 2 diabetes (4), the changes in body composition after the onset of diabetes are not well documented. We have observed cross-sectionally that older adults with type 2 diabetes have an altered body composition and low skeletal muscle strength compared with nondiabetic older adults (5). We also reported that older adults with type 2 diabetes lost their knee extensor strength more rapidly than their nondiabetic counterparts (6).The effects of type 1 diabetes on protein metabolism seem to be clear, as insulin deprivation causes a profound increase in catabolism, especially in skeletal muscle (7,8). However, the effect of type 2 diabetes on protein metabolism is less clear, since the results of previous studies are inconsistent (9–12). Few studies have examined the effect of type 2 diabetes on the quantity of skeletal muscle mass in humans.In the Health, Aging, and Body Composition Study (Health ABC Study), we assessed the changes in total and regional lean and fat mass over 6 years with precise measures of body composition with dual-energy X-ray absorptiometry (DEXA) and computed tomography (CT). The aim of the study was to investigate the impact of type 2 diabetes on the changes in body composition, with particular interest on the skeletal muscle, in community-dwelling well-functioning older adults. We hypothesized that older adults with type 2 diabetes would show more loss of lean skeletal muscle mass than older adults without diabetes.     

Exenatide Affects Circulating Cardiovascular Risk Biomarkers Independently of Changes in Body Composition

OBJECTIVE

To study the effect of exenatide on body composition and circulating cardiovascular risk biomarkers.

RESEARCH DESIGN AND METHODS

Metformin-treated patients with type 2 diabetes (N = 69) were randomized to exenatide or insulin glargine and treated for 1 year. Body composition was evaluated by dual-energy X-ray absorptiometry. Additionally, body weight, waist circumference, and cardiovascular biomarkers were measured.

RESULTS

Treatment with exenatide for 1 year significantly reduced body weight, waist circumference, and total body and trunkal fat mass by 6, 5, 11, and 13%, respectively. In addition, exenatide increased total adiponectin by 12% and reduced high-sensitivity C-reactive protein by 61%. Insulin glargine significantly reduced endothelin-1 by 7%. These changes were statistically independent of the change in total body fat mass and body weight.

CONCLUSIONS

Exenatide treatment for 1 year reduced body fat mass and improved the profile of circulating biomarkers of cardiovascular risk. No significant changes were seen with insulin glargine except a trend for reduced endothelin-1 levels.Abdominal obesity is associated with both type 2 diabetes and metabolic complications (1), including elevations in several circulating biomarkers of cardiovascular risk (2). Most pharmacological glucose-lowering treatments increase body weight (3). Therefore, treatments that not only reduce A1C, but also improve other associated changes such as abdominal obesity are urgently needed (4).We previously reported in Diabetes Care that exenatide improves glycemic control to the same extent as insulin glargine, although exenatide decreased and insulin glargine raised body weight (5). Herein we present additional data on associated changes in body composition and circulating levels of biomarkers of cardiovascular risk after 1 year of treatment.     

Weight matters: physical and psychosocial well being of persons with spinal cord injury in relation to body mass index

Chen Y, Cao Y, Allen V, Richards JS. Weight matters: physical and psychosocial well being of persons with spinal cord injury in relation to body mass index.

Objective

To examine the relationship of body mass index (BMI) with multiple health indices among persons with spinal cord injury (SCI).

Design

Multicenter cross-sectional study.

Setting

A total of 16 SCI Model Systems throughout the United States.

Participants

A total of 1107 men and 274 women (N=1381), mean age ± SD, 43.1±14.6 years (tetraplegia, 56.9%; complete injuries, 50.2%; mean years since injury ± SD, 7.8±8.6), who received follow-up in 2006 to 2009, were classified into 1 of the 4 BMI categories—underweight, normal, overweight, and obese—based on self-reported height and measured weight.

Interventions

Not applicable.

Main Outcome Measures

Rehospitalization, pain, self-perceived health, FIM, Craig Handicap Assessment and Reporting Technique, Patient Health Questionnaire-9 (PHQ-9), and the Diener's Satisfaction With Life Scale (SWLS).

Results

The prevalence of underweight, overweight, and obesity was 7.5%, 31.4%, and 22.1%, respectively, which varied by age, sex, marital status, education, and neurologic impairment. For those with tetraplegia and functional motor-complete injuries, rehospitalization occurred more frequently among obese persons, while days rehospitalized were the longest among underweight persons. Pain was more severe in those classified as obese. Community mobility was lower in the underweight, overweight, and obese groups than in those with normal weight. There was no significant association between BMI and self-perceived health, FIM, PHQ-9, and SWLS beyond the effect of neurologic impairment.

Conclusions

Prevention and intervention directed at those significantly overweight or underweight deserve consideration as priorities in the continuity of care for persons with SCI. Efforts should be targeted particularly to those at higher risk, including persons with more severe injuries, who are less educated, and who are living alone.     

Intergenerational Cardiovascular Disease Risk Factors Involve Both Maternal and Paternal BMI

OBJECTIVE

To examine the association between parental BMI and offspring cardiovascular disease (CVD) risk factors.

RESEARCH DESIGN AND METHODS

The study comprised 940 children (9.5 ± 0.4 years) and 873 adolescents (15.5 ± 0.5 years). Parental weight and height were reported by the mother and the father, and BMI was calculated. CVD risk factors included total (sum of five skinfolds) and central (waist circumference) body fat, blood pressure, cardiorespiratory fitness, insulin sensitivity, total cholesterol, HDL cholesterol, triglycerides, and fibrinogen.

RESULTS

Maternal and paternal BMI were positively associated with total and central fatness in offspring (P < 0.001). BMIs of both parents were significantly related to fibrinogen levels (P < 0.02), but these associations disappeared when controlling for fatness. There was a positive relationship between maternal and paternal BMI and waist circumference in the offspring regardless of total adiposity and height (P < 0.001). Maternal BMI was negatively associated with offspring cardiorespiratory fitness independently of fatness (P < 0.02). These relationships persisted when overweight descendants were excluded from the analysis. There were no significant associations between parental BMI and the other CVD risk factors.

CONCLUSIONS

Both maternal and paternal BMI increase CVD risk factors of their offspring, characterized by total and central body fat, and higher maternal BMI was associated with poorer cardiorespiratory fitness. Our findings give further support to the concept that adiposity in parents transmits susceptibility to CVD risk to descendants, which is detectable even in the absence of overweight in offspring.Parental obesity substantially increases the risk of obesity in offspring through genetic, biological, or environmental influences (1). The fetal overnutrition hypothesis suggests that maternal obesity and/or gestational diabetes may predispose offspring to increased adiposity in adulthood (2). Human studies showed a greater influence of maternal than paternal BMI on offspring adiposity (3,4). In contrast, others suggested that the contribution of the mother and the father on both prenatal and postnatal programming of intergenerational obesity may be similar according to the genomic imprinting (5).Most of the studies focused on the relationships of maternal and paternal BMI with their offspring BMI provided contradictory results (3,6,7), and only one study compared the association of maternal and paternal BMI with total body fat in the offspring (8). Whether the parental BMI-offspring body fat relationship applies to other established cardiovascular disease (CVD) risk factors remains to be elucidated.Excess adiposity leads to increased CVD risk factors and biological pathway alterations as insulin resistance, dyslipemia, hypertension, systemic inflammation, and low cardiorespiratory fitness (9). Therefore, the parental BMI-offspring CVD risk factor relationship may be influenced by the offspring body composition.The European Youth Heart Study (EYHS) provides an opportunity to better understand the parental-descendant aggregation of CVD factors by controlling for other potential confounding factors that could mediate in this relationship. Therefore, the aim of this study was to determine the association between both maternal and paternal BMI and the offspring CVD risk factors including total and central body fat, cardiorespiratory fitness, insulin sensitivity, blood pressure, blood lipids, and fibrinogen. We also examined the role of offspring adiposity in this relationship.     

Correlation of Body Composition and Low Back Pain Severity in a Cross-Section of US Veterans

Objective

Back pain is more prevalent in the obese, but whether back pain severity is directly correlated to obesity in veterans is unknown. We sought to determine if there was a correlation between body composition and low back pain severity in a sample of veterans. The hypothesis was that veterans with higher body mass index values would report higher low back pain severity scores.

Complex relationship of obesity and obesity paradox in heart failure – higher risk of developing heart failure and better outcomes in established heart failure

Heart failure (HF) and obesity are major public health problems. Studies have shown that obesity may increase the risk of developing new HF but after patients have developed HF, obesity may be associated with improved outcomes. This paradoxical association of obesity with HF remains poorly understood. It is believed that the obesity paradox may in part be due to the inherent limitations of body mass index (BMI) as a measure of obesity. BMI may not appropriately measure important components of body mass like body fat, fat distribution, lean body mass, and body fluid content and may not be ideal for examining the relationship of body composition with health outcomes. Differentiating between body fat and lean body mass may explain some of the paradoxical association between higher BMI and better prognosis in patients with HF. Paradoxical outcomes in HF may also be due to phenotypes of obesity. Future studies need to develop and test metrics that may better measure body composition and may serve as a better tool for the estimation of the true association of obesity and outcomes in HF and determine whether the association may vary by obesity phenotypes.

• KEY MESSAGES

• Obesity predisposes to heart failure in all age groups. But obesity in heart failure is an area of controversy, because of obesity paradox, the apparent protective effect of overweight and mild obesity on mortality after development of heart failure.

• Traditional markers of obesity do not measure different components of body weight like muscle mass, fat, water, and skeletal weight. Body Mass Index in heart failure subjects does not measure accurately body fat or fluid retention. So new markers of obesity like visceral adiposity index, body composition analysis, sarcopenic status assessment may be helpful in the assessment of heart failure outcomes.

• Different phenotypes of obesity may be responsible for the different morbidity, mortality as well as therapeutic outcomes in heart failure.

     

Correlation between postprandial bile acids and body fat mass in healthy normal-weight subjects

Background

Bile acids (BAs) play important roles in glucose regulation and energy homeostasis via G protein-coupled receptors, such as enteroendocrine L cell TGR5. The aim of the present study was to investigate the relationship between postprandial BA levels and body composition after ingestion of a standard test meal.

Methods

Eleven healthy subjects of normal weight (body-mass index, 22.0 ± 1.6 kg/m² [mean ± SD]), ingested a 400-kcal test meal, and blood samples were obtained from them before ingestion and every 30 min for 120 min after ingestion. The BA fractions were measured with high-performance liquid chromatography. To evaluate body composition, body impedance analysis was performed 1 h before ingestion of the test meal.

Results

Concentrations of both total BA and total glycine-conjugated BA (GCBA) at 30, 60, 90, and 120 min after test-meal ingestion were significantly higher than those at baseline. The body-mass index was correlated with total GCBA at baseline. Moreover, body fat mass was correlated with total GCBA at 30 min (r = – 0.688, P = 0.019) and 60 min (r = – 0.642, P = 0.033) and with total BA at 30 min (r = – 0.688, P = 0.019) and 60 min (r = – 0.642, P = 0.033).

Conclusion

The postprandial BA response is inversely related with body fat mass in healthy subjects of normal weight.     

Relationship Between Perceived Exertion and Physiologic Markers During Arm Exercise With Able-Bodied Participants and Participants With Poliomyelitis

Al-Rahamneh HQ, Faulkner JA, Byrne C, Eston RG. Relationship between perceived exertion and physiologic markers during arm exercise with able-bodied participants and participants with poliomyelitis.

Objective

To investigate the strength of the relationship between ratings of perceived exertion (RPE) and oxygen uptake (V?o₂), heart rate, ventilation (V?e) and power output (PO) during an arm-crank ramped exercise test to volitional exhaustion in men and women who differed in physical status.

Design

Each participant completed an arm-crank ramp exercise test to volitional exhaustion. PO was increased by 15W·min⁻¹ and 6W·min⁻¹ for men and women able-bodied participants, respectively; for the poliomyelitis participants, 9W·min⁻¹ and 6W·min⁻¹ increments were used for men and women, respectively.

Setting

Laboratory facilities at a university.

Participants

Able-bodied participants (n=16; 9 men, 7 women) and participants with poliomyelitis (n=15, 8 men, 7 women) volunteered for the study.

Main Outcome Measures

Strength of the relationship (R² values) between RPE and V?o₂, heart rate, V?e and PO.

Results

There were significantly higher values for maximum V?o₂ and maximum PO for able-bodied men compared with their counterparts with poliomyelitis (P<.05). However, when the data were controlled for age, there were no significant differences in these values (P>.05). Similar results were observed for the women who were able-bodied as well as for the women who had poliomyelitis (P>.05). The relationships between heart rate and RPE and V?e and RPE for able-bodied patients and patients with poliomyelitis were similar (R²>.87). The relationship between V?o₂ and RPE was stronger in the able-bodied participants compared wih the participants with poliomyelitis, regardless of sex (P<.05). However, when the data were controlled for age, there was no significant difference in the strength of this relationship between able-bodied participants and those with poliomyelitis, regardless of sex (P>.05).

Conclusions

RPE is strongly related to physiologic markers of exercise intensity during arm exercise, irrespective of sex or participant's poliomyelitis status.     

Determinants of body fat in infants of women with gestational diabetes mellitus differ with fetal sex

OBJECTIVE

Neonatal adiposity is a well-recognized complication of gestational diabetes mellitus (GDM). This study aimed to identify factors influencing adiposity in male and female infants of women treated for GDM.

RESEARCH DESIGN AND METHODS

This was a prospective study of 84 women with GDM. Daily blood glucose levels (BGLs) were retrieved from glucose meters, and overall mean fasting and mean 2-h postprandial BGLs were calculated for each woman. Infant body composition was measured at birth, and regression analysis was used to identify significant predictors of infant body fat separately in male and female infants.

RESULTS

Maternal fasting BGL was the major predictor of adiposity in male infants but had little relationship to adiposity in female infants. In male infants, percent fat was increased by 0.44% for each 0.1 mmol/L increase in mean maternal fasting BGL. Maternal BMI was the primary predictor in female infants but had little effect in males. In female infants, percent fat was increased by 0.11% for each 1 kg/m² increase in maternal prepregnancy BMI.

CONCLUSIONS

Fetal sex may influence the impact that treatment strategies for GDM have on infant adiposity.The maternal metabolic disturbance of gestational diabetes mellitus (GDM) affects fetal development and alters birth weight, BMI, and percent body fat at birth (1,2). Current treatment of GDM achieves normalization of birth weight and reduces neonatal complications (3). However, the effects of GDM on the offspring extend well beyond the fetal period and, thus, offspring of women with GDM also have an increased risk of unfavorable long-term outcomes such as obesity and diabetes, well above that explained by genetics alone (4), even after treatment.To date, studies designed to inform optimal treatment of GDM have focused on normalization of birth weight, but neonatal adiposity may be a more sensitive marker of disturbed in utero metabolism, risk of obesity, and poor long-term health than birth weight alone (1). Body fat at birth is elevated in infants born to women with GDM even when birth weight is normal (1). In a group of 6- to 12-year-old children born to women with GDM, percent body fat in childhood was significantly correlated to body fat at birth, but there was no relationship between birth weight and weight at the time of study (5). Even though treatment of mild GDM does reduce the incidence of macrosomia, it does not reduce the incidence of obesity in the offspring at 4–5 years (6).To interrupt the obesity cycle and reduce the risk of future poor adult health, it may be necessary to normalize neonatal adiposity as well as birth weight. To do this, it is essential to understand the factors that determine adiposity in infants of women with GDM.While genetic factors may be the primary determinant of lean body mass, fetal fat mass may be more strongly influenced by the in utero environment (7). A range of maternal factors have been identified as determinants of neonatal size and body fat, including maternal BMI, parity, maternal glucose concentration, and insulin sensitivity (8–10). Higher gestational weight gain is associated with increased infant birth weight in lean and moderately overweight women (11) and in women with normal glucose tolerance (9) but not in obese women (11) or women with GDM (9). However, the factors influencing fetal fat accretion remain poorly understood.Both body weight and body composition at birth are different in male and female infants (12), and sex of the infant has been reported as a significant determinant of each (9). We hypothesized that the determinants of fetal body composition may also differ with fetal sex. The aim of this study was to identify factors that influence adiposity in male and female infants born to women treated for GDM.     

Early Life Programming of Abdominal Adiposity in Adolescents: The HELENA Study

OBJECTIVE

To examine the relationship between birth weight and abdominal adiposity in adolescents.

RESEARCH DESIGN AND METHODS

A total of 284 adolescents (49.3% of whom were female) aged 14.9 ± 1.2 years were included in the study. Birth weight and gestational age were obtained from parental records. Abdominal adiposity (in three regions: R1, R2, and R3) and trunk and total body fat mass were measured by dual-energy X-ray absorptiometry. Regional fat mass indexes (FMIs) were thereafter calculated as fat mass divided by the square of height (Trunk FMI and abdominal FMI R1, R2, and R3).

RESULTS

Birth weight was negatively associated with abdominal FMI R1, R2, and R3 independently of total fat mass, gestational age, sex, breast-feeding duration, pubertal stage, physical activity, and socioeconomic status (all P < 0.01).

CONCLUSIONS

Our study shows an inverse association between birth weight and abdominal adiposity in adolescents independently of total fat mass and other potential confounders. These findings suggest that fetal nutrition, as reflected by birth weight, may have a programming effect on abdominal adiposity later in life.Low birth weight seems to increase the risk of type 2 diabetes and cardiovascular disease by programming a more central fat deposition (1). However, the association between birth weight and fat distribution remains controversial (2–4). Studies using advanced methods to assess body composition such as dual-energy X-ray absorptiometry (DEXA) may help to better describe these asso- ciations.The aim of this study was to examine the relationship between birth weight and abdominal adiposity measured by DEXA in Spanish adolescents participating in the Healthy Lifestyle in Europe by Nutrition in Adolescence Cross-Sectional study (HELENA-CSS).     

Trajectories in the Course of Body Mass Index After Spinal Cord Injury

Objective

To identify different trajectories of the course of body mass index (BMI) after spinal cord injury (SCI) and to study whether other cardiovascular risk factors (blood pressure, lipid profile) follow the same trajectories.

Design

Multicenter prospective cohort study with measurements at the start of active rehabilitation, after 3 months, at discharge, and 1 and 5 years after discharge.

Setting

Rehabilitation centers.

Participants

Persons with a recent SCI (N=204).

Interventions

Not applicable.

Main Outcome Measure

BMI trajectories.

Results

Three BMI trajectories were identified: (1) a favorable stable BMI during and after rehabilitation (±22–23kg/m²) (54%); (2) a higher but stable BMI during inpatient rehabilitation (±24kg/m²) and an increase after discharge (up to 29kg/m²) (38%); and (3) an increase in BMI during inpatient rehabilitation (from ±23 up to 28kg/m²) and leveling off after discharge (8%). Profile analyses showed that an unfavorable change in BMI was not accompanied by clear unfavorable changes in blood pressure or lipid levels.

Conclusions

BMI in people with SCI follows distinct trajectories. Monitoring body mass, food intake, and daily physical activity during and especially after inpatient SCI rehabilitation is important to prevent obesity and related cardiovascular risk factors.     

Internet-Delivered Lifestyle Physical Activity Intervention Improves Body Composition in Multiple Sclerosis: Preliminary Evidence From a Randomized Controlled Trial

Objective

To examine the efficacy of a physical activity behavioral intervention for improving outcomes of body composition in persons with multiple sclerosis (MS).

Design

Secondary analysis of data from a randomized controlled trial.

Setting

University research laboratory.

Participants

Ambulatory persons with MS (N=82).

Intervention

A 6-month, internet-delivered physical activity behavioral intervention designed to increase lifestyle physical activity, primarily walking. The behavioral intervention was based on principles of social cognitive theory.

Main Outcome Measures

Whole-body bone mineral content (BMC), bone mineral density (BMD), and soft tissue composition, using dual-energy x-ray absorptiometry.

Results

There were no significant differences between conditions posttrial on body composition outcomes using the adjusted critical value (P<.008). There was a significant effect of the intervention on whole-body BMC (P=.04, ω²<.001) and BMD (P=.01, ω²=.003) using the unadjusted critical value (P<.05). The effect of the intervention on percent body fat (P=.09, ω²=.001) and whole-body fat mass (P=.05, ω²=.003) approached significance using unadjusted criteria. There was not a significant effect on whole-body lean soft tissue (P=.28, ω²<.001) or body mass index (P=.86, ω²<.001).

Conclusions

Our results provide preliminary evidence that an internet-delivered lifestyle physical activity intervention might improve bone health and body composition in MS. Such findings are important considering that physical activity is a modifiable behavior with the potential to confer long-term benefits for the prevention and management of fracture risk and comorbidities among those with MS.     

Normalizing hip muscle strength: establishing body-size-independent measurements

Bazett-Jones DM, Cobb SC, Joshi MN, Cashin SE, Earl JE. Normalizing hip muscle strength: establishing body-size-independent measurements.

Objective

To investigate the effectiveness of computing body-size-independent hip strength measures using muscle-specific allometric scaling and ratio standard normalization methods.

Design

Cross-sectional study.

Setting

University laboratory.

Participants

A convenience sample of healthy participants (N=113; 42 men, 71 women).

Interventions

Not applicable.

Main Outcome Measures

Anthropometric measurements of the leg and thigh were obtained, and maximal hip strength was tested (medial and lateral rotation, abduction, adduction, flexion, extension). Strength was measured isometrically as force (kg) and then converted to torque (Nm).

Results

The allometric scaling analysis resulted in exponents for normalizing body mass (BM) in each muscle group assessed. In addition, a 6-muscle average exponent was also computed (bavg) for force (men, .554; women, .335) and torque (men, .792; women, .482). The nonsignificant results of the linear regression analysis revealed that normalizing hip strength to BM^bavg (hip strength/BM^bavg) effectively removed the influence of BM on force and torque. However, sex should be factored into analyses of allometric scaling because men have higher b-values than women for both force and torque. The linear regression analyses also demonstrated that force normalized to BM (P=.162–.895) and torque normalized to BM × Height (P=.146–.889) were body-size-independent measures. Force normalized to BM^0.67 (P=.001–.191) and body mass index (BMI) (P=<.001–.066), and torque normalized to BM (P=.004–.415) and BMI (P<.001) were significantly related to BM and therefore were not body-size independent.

Conclusions

Normalizing force and torque to BM^bavg is the most effective method of removing body-size dependence and allowing comparisons of persons with differing body sizes.     

Maternal glucose concentration during pregnancy predicts fat and lean mass of prepubertal offspring

OBJECTIVE

Intrauterine exposure to high maternal glucose is associated with excess weight gain during childhood, but it is not clear whether the excess weight represents increased fat or lean mass. The purpose of this study was to examine the relationship between maternal glucose concentrations during pregnancy and offspring body composition. A secondary goal was to examine whether the association between maternal glucose and children’s body fat was independent of energy intake, energy expenditure, or physical activity.

RESEARCH DESIGN AND METHODS

Children aged 5–10 years and their biological mothers (n = 27) were recruited. Maternal glucose concentration 1 h after a 50-g oral glucose load, used to screen for gestational diabetes mellitus at 24–28 weeks gestation, was retrieved from medical records. Children underwent dual-energy X-ray absorptiometry to measure body composition, indirect calorimetry to measure resting energy expenditure (REE), accelerometry to measure physical activity, and three 24-h diet recalls to measure energy intake.

RESULTS

Maternal glucose concentration during pregnancy was positively associated with children’s lean mass (P < 0.05) and adiposity (fat mass adjusted for lean mass; P < 0.05). The association between maternal glucose and children’s adiposity was independent of children’s REE, percent of time spent physically active, and energy intake (P < 0.001).

CONCLUSIONS

Intrauterine exposure to relatively high maternal glucose is associated with greater lean mass and adiposity among prepubertal offspring. Further research is needed to examine the mechanisms by which maternal glucose concentrations during pregnancy influence children’s body composition.Children born to diabetic women (1–3) or those with relatively high glucose concentrations during pregnancy (4,5) have greater birth weight and are at greater risk for obesity than are those born to nondiabetic women. These conclusions are based on measures of BMI percentiles or skin fold measures of subcutaneous fat, and so it is not clear whether the larger body size among offspring of diabetic women also reflects greater lean mass in addition to greater fat mass. Excess childhood weight gain among offspring of diabetic mothers is believed to be a result of prenatal exposure to increased fuel from the mother, and glucose has been specifically implicated (6,7). It would be of interest, therefore, to examine the association between maternal glucose concentrations during pregnancy across a range incorporating both diabetic and nondiabetic extremes and children’s fat and lean mass.Despite the large body of literature supporting associations of maternal diabetes and glucose concentrations with offspring body weight, it is not known whether greater energy intake or reduced expenditure among offspring contributes to this effect. Evidence from animal models supports the hypothesis that regulation of appetite and energy balance may be impaired following prenatal exposure to high maternal glucose (rev. in 8), but in clinical studies, investigators have found no difference in energy expenditure, physical activity, or energy intake under controlled conditions among children with and without prenatal exposure to maternal diabetes (9,10). These studies did not consider maternal glucose concentration specifically, however, which may vary considerably in women with diabetes based on their degree of glycemic control.The purpose of this study was to test the hypothesis that prepubertal children who were prenatally exposed to relatively high maternal glucose concentrations would have greater fat, but not lean, mass. A secondary hypothesis was to examine whether this association was independent of children’s energy intake, expenditure, or physical activity. These hypotheses were tested in prepubertal children for whom mothers’ medical records during pregnancy were available.     

Asymptomatic median mononeuropathy among men with chronic paraplegia

Liang H-W, Wang Y-H, Pan S-L, Wang TG, Huang T-S. Asymptomatic median mononeuropathy among men with chronic paraplegia.

Objectives

To compare electrophysiologic abnormalities of the median nerve in asymptomatic paraplegic subjects and able-bodied controls and to examine the influence of personal factors on these parameters.

Design

Cross-sectional survey.

Setting

University hospital.

Participants

Forty-seven men with paraplegia and 36 able-bodied controls underwent nerve conduction studies on both upper limbs. All were free of hand numbness in the past month, diabetic mellitus, or neuromusculoskeletal injuries to the upper limbs.

Interventions

Not applicable.

Main Outcome Measure

Nerve conduction studies of the bilateral median and ulnar nerves.

Results

Although the 2 groups were of comparable age and had a similar body mass index (BMI), the subjects with paraplegia had a significantly higher proportion of asymptomatic median mononeuropathy than the controls (25.5% vs 5.6%, P=.02). The spinal cord injury (SCI) group had a prolonged median distal latency and a slowed digit-wrist sensory nerve conduction velocity. Multivariate general linear model analysis showed that prolonged motor and sensory latencies of the median nerve were associated with the SCI group and with greater BMI.

Conclusions

The asymptomatic subjects with paraplegia had a significantly higher frequency of median mononeuropathy than the able-bodied controls. There was also an association between BMI and distal latency of the median nerve.