Is percentage body fat differentially related to body mass index in Hispanic Americans, African Americans, and European Americans?

Assessing the state of obesity care: Quality, access, guidelines, and standards

Background

An international panel of obesity medicine experts from multiple professional organizations examined patterns of obesity care and current obesity treatment guidelines to identify areas requiring updating in response to emerging science and clinical evidence.

Aims

The panel focused on multiple medical health and societal issues influencing effective treatment of obesity and identified several unmet needs in the definition, assessment, and care of obesity.

Methods

The panel was held in Leesburg, Virginia in September 2019.

Results

The panelists recommended addressing these unmet needs in obesity medicine through research, education, evaluation of delivery and payment of care, and updating clinical practice guidelines (CPG) to better reflect obesity's pathophysiological basis and heterogeneity, as well as the disease's health, sociocultural, and economic complications; effects on quality of life; need for standards for quantitative comparison of treatment benefits, risks, and costs; and the need to more effectively integrate obesity treatment guidelines into routine clinical practice and to facilitate more direct clinician participation to improve public understanding of obesity as a disease with a pathophysiological basis. The panel also recommended that professional organizations working to improve the care of people with obesity collaborate via a working group to develop an updated, patient-focused, comprehensive CPG establishing standards of care, addressing identified needs, and providing for routine, periodic review and updating.

Conclusions

Unmet needs in the definition, assessment and treatment of obesity were identified and a blueprint to address these needs developed via a clinical practice guideline that can be utilized worldwide to respond to the increasing prevalence of obesity.

General or Central Obesity and Mortality Among US Hispanic and Latino Adults

Importance

The Hispanic and Latino population is the second largest ethnic group in the US, but associations of obesity parameters with mortality in this population remain unclear.

Objective

To investigate the associations of general and central obesity with mortality among US Hispanic and Latino adults.

Design, Setting, and Participants

The Hispanic Community Health Study/Study of Latinos is an ongoing, multicenter, population-based cohort study with a multistage probability sampling method performed in Hispanic and Latino adults aged 18 to 74 years with a baseline between January 1, 2008, and December 31, 2011. Active follow-up for this analyses extended from baseline through February 17, 2022. All analyses accounted for complex survey design (ie, stratification and clustering) and sampling weights to generate estimates representing the noninstitutionalized, 18- to 74-year-old Hispanic or Latino populations from selected communities.

Exposures

Body mass index (BMI; calculated as weight in kilograms divided by height in meters squared), body fat percentage, waist circumference (WC), and waist to hip ratio (WHR).

Main Outcome and Measure

Deaths were ascertained via death certificates, the National Death Index, and active follow-up.

Results

Of 15 773 adults (mean [SE] age, 40.9 [0.3] years; 52.8% female), 686 deaths occurred during a median (IQR) follow-up of 10.0 (9.9-10.2) years. When adjusting for sociodemographic, lifestyle, and family history covariates, hazard ratios (HRs) for mortality were 1.55 (95% CI, 1.08-2.22) for a BMI of 35.0 or greater vs 18.5 to 24.9, 1.22 (95% CI, 0.92-1.64) for the highest vs lowest body fat percentage groups (defined according to sex-, age-, and Hispanic or Latino background-specific BMI distribution), 1.35 (95% CI, 0.98-1.85) for WC greater than 102 cm (men) or 88 cm (women) vs 94 cm (men) or 80 cm (women) or less, and 1.91 (95% CI, 1.28-2.86) for WHR of 0.90 (men) or 0.85 (women) or greater vs less than 0.90 (men) or 0.85 (women). Only WHR was associated with mortality with additional adjustment for major comorbidities (HR, 1.75; 95% CI, 1.17-2.62). The association of WHR with mortality was stronger among women compared with men (P = .03 for interaction), and the association between BMI and mortality was stronger among men (P = .02 for interaction). The positive association between severe obesity (BMI ≥ 35.0) and mortality was observed only among adults with WHR of 0.90 (men) or 0.85 (women) or greater but not among those with WHR below 0.90 (men) or 0.85 (women) (P = .005 for interaction) who had greater hip circumference.

Conclusions and Relevance

In this cohort of US Hispanic and Latino adults, WHR was independently associated with higher all-cause mortality regardless of BMI and prevalent comorbidities. These findings suggest that prioritizing clinical screening and intervention for WHR in this population may be an important public health strategy, with sex-specific strategies potentially being needed.

Trends in weight change patterns across life course among US adults, 1988-2018: population-based study

BACKGROUND

To examine trends in weight change patterns from young adulthood through midlife to late adulthood and their sex and racial/ethnic disparities among US adults from 1988 to 2018.

METHODS

A total of 48,969 participants from the National Health and Nutrition Examination Survey 1988-1994 and 2001-2018 were included.

RESULTS

The age-adjusted prevalence of stable non-obesity between young adulthood and midlife declined significantly from 84.1% (95 CI, 82.9-85.3%) in 1988-1994 to 68.7% (67.1-70.2%) in 2013-2018, and between midlife and late adulthood from 71.2% (69.2-73.1%) to 52.4% (50.5-54.2%). The magnitude of increase in the prevalence of weight gain from young adulthood to midlife (from 10.8% [9.9-11.6%] in 1988-1994 to 21.2% [20-22.3%] in 2013-2018; P < 0.001 for trend) was greater than that from midlife to late adulthood (from 14.1% [12.9-15.3%] to 17.2% [16.2-18.1%]; P = 0.002 for trend). The magnitude of increase in the prevalence of stable obesity from young adulthood to midlife (from 3.9% [3.1-4.8%] in 1988-1994 to 9.2% [8.2-10.3%] in 2013-2018; P < 0.001 for trend) was smaller than that from midlife to late adulthood (from 11.2% [10.1-12.2%] to 24.8% [23.3-26.3%]; P < 0.001 for trend). The declining trends in the prevalence of stable non-obesity and increasing trends in the prevalence of weight gain and stable obesity from young adulthood through midlife to late adulthood were also observed for all sex and race/ethnicity subgroups. The magnitude of decrease in the prevalence of stable non-obesity, and the magnitude of increase in the prevalence of weight gain from young adulthood through midlife to late adulthood were greater in men than in women (all P for interaction < 0.01). Weight gain patterns for those aged ≥ 65 years were substantially different from the younger age groups.

CONCLUSIONS

More young people born in later years are encountering obesity and accumulate greater obesity exposure across their lives than young people born in earlier years.

Adherence to the American Cancer Society Guidelines on nutrition and physical activity for cancer prevention and obesity-related cancer risk and mortality in Black and Latina Women's Health Initiative participants

BACKGROUND

Although adherence to the American Cancer Society (ACS) Guidelines on Nutrition and Physical Activity for Cancer Prevention associates with lower risk of obesity-related cancer (ORC) incidence and mortality, evidence in Black and Latina women is limited. This association was examined in Black and Latina participants in the Women's Health Initiative (WHI).

METHODS

Semi-Markov multistate model examined the association between ACS guideline adherence and ORC incidence and mortality in the presence of competing events, combined and separately, for 9301 Black and 4221 Latina postmenopausal women. Additionally, ACS guideline adherence was examined in a subset of less common ORCs and potential effect modification by neighborhood socioeconomic status and smoking.

RESULTS

Over a median of 11.1, 12.5, and 3.7 years of follow-up for incidence, nonconditional mortality, and conditional mortality, respectively, 1191 ORCs (Black/Latina women: 841/269), 1970 all-cause deaths (Black/Latina women: 1576/394), and 341 ORC-related deaths (Black/Latina women: 259/82) were observed. Higher ACS guideline adherence was associated with lower ORC incidence for both Black (cause-specific hazard ratio [CSHR]_highvs.low : 0.72; 95% CI, 0.55-0.94) and Latina (CSHR_highvs.low : 0.58, 95% CI, 0.36-0.93) women; but not conditional all-cause mortality (Black hazard ratio [HR]_highvs.low : 0.86; 95% CI, 0.53-1.39; Latina HR_highvs.low : 0.81; 95% CI, 0.32-2.06). Higher adherence was associated with lower incidence of less common ORC (P_trend  = .025), but conditional mortality events were limited. Adherence and ORC-specific deaths were not associated and there was no evidence of effect modification.

CONCLUSIONS

Adherence to the ACS guidelines was associated with lower risk of ORCs and less common ORCs but was not for conditional ORC-related mortality.

LAY SUMMARY

Evidence on the association between the American Cancer Society Guidelines on Nutrition and Physical Activity for Cancer Prevention and cancer remains scarce for women of color. Adherence to the guidelines and risk of developing one of 13 obesity-related cancers among Black and Latina women in the Women's Health Initiative was examined. Women who followed the lifestyle guidelines had 28% to 42% lower risk of obesity-related cancer. These findings support public health interventions to reduce growing racial/ethnic disparities in obesity-related cancers.

Effect of soft tissue noise on trabecular bone score in postmenopausal women with diabetes: A cross sectional study

BACKGROUND

Type 2 diabetes (T2D) is associated with increased fracture risk, despite similar or greater BMD compared to nondiabetics. TBS predicts fracture risk in T2D and nondiabetics. However, increased abdominal thickness, a common feature in T2D, may reduce TBS values.

AIM

To study the relationship among glycemic status, BMD and TBS, considering abdominal soft tissue thickness (STT) interference.

METHODS

Cross-sectional analysis of 493 women ≥65 years, with simultaneous DXA scans and HbA1c measures. STT and TBS (iNsight Software, v3.0) were derived from lumbar spine (LS) scans. Subjects were divided according to HbA1c levels: 1 (≥6.5%; n = 116), 2 (5.7-6.4%; n = 217) and 3 (≤5.6%; n = 160). Group 1 was further divided based on HbA1c and/or disease duration: 1a (HbA1c ≥ 7.5%; n = 42), 1b (HbA1c ≥ 6.5% and disease duration ≥5 years; n = 63) and 1c (HbA1c ≥ 7.5% and disease duration ≥5 years; n = 30).

FINDINGS

For the entire cohort, mean age, TBS, BMI and STT were 71.8 ± 6.0 years, 1.299 ± 0.101, 26.9 ± 4.1 kg/m², and 21.4 ± 2.9 cm, respectively. LS-BMD was similar among groups. BMD in hip sites and STT were higher in group 1. TBS was lower in patients with higher HbA1c (P = 0.020), with a mean TBS in groups 1, 2, and 3 of 1.280, 1.299 and 1.314, respectively. This difference remained after adjusting for age, LS-BMD and BMI (P = 0.010). After replacing BMI with STT, TBS differences were no longer significant (P = 0.270). The same was observed when subgroups 1a and 1b were compared to group 3. However, for subgroup 1c, TBS remained lower compared to group 3, even after adjusting for age, LS-BMD and STT, with a borderline P-value (1.275 vs. 1.308; P = 0.047).

CONCLUSION

Higher HbA1c levels were associated with greater BMD in hip sites, higher abdominal STT and lower TBS values. However, after including the STT in the adjustment, TBS differences among groups disappeared, except in women with higher HbA1c levels and longer disease duration.

Impact of common cardio-metabolic risk factors on fatal and non-fatal cardiovascular disease in Latin America and the Caribbean: an individual-level pooled analysis of 31 cohort studies

Background

Estimates of the burden of cardio-metabolic risk factors in Latin America and the Caribbean (LAC) rely on relative risks (RRs) from non-LAC countries. Whether these RRs apply to LAC remains unknown.

Methods

We pooled LAC cohorts. We estimated RRs per unit of exposure to body mass index (BMI), systolic blood pressure (SBP), fasting plasma glucose (FPG), total cholesterol (TC) and non-HDL cholesterol on fatal (31 cohorts, n=168,287) and non-fatal (13 cohorts, n=27,554) cardiovascular diseases, adjusting for regression dilution bias. We used these RRs and national data on mean risk factor levels to estimate the number of cardiovascular deaths attributable to non-optimal levels of each risk factor.

Results

Our RRs for SBP, FPG and TC were like those observed in cohorts conducted in high-income countries; however, for BMI, our RRs were consistently smaller in people below 75 years of age. Across risk factors, we observed smaller RRs among older ages. Non-optimal SBP was responsible for the largest number of attributable cardiovascular deaths ranging from 38 per 100,000 women and 54 men in Peru, to 261 (Dominica, women) and 282 (Guyana, men). For non-HDL cholesterol, the lowest attributable rate was for women in Peru (21) and men in Guatemala (25), and the largest in men (158) and women (142) from Guyana.

Interpretation

RRs for BMI from studies conducted in high-income countries may overestimate disease burden metrics in LAC; conversely, RRs for SBP, FPG and TC from LAC cohorts are similar to those estimated from cohorts in high-income countries.

Funding

Wellcome Trust (214185/Z/18/Z).

Obesity and Race May Explain Differential Burden of White Matter Hyperintensity Load

OBJECTIVE

Compared to European Americans, research indicates that African Americans have higher white matter hyperintensity (WMH) load; however, the clinical and biological bases underlying this higher burden are poorly understood. We hypothesize that obesity may explain differences in WMH between African and European Americans.

METHODS

Participants enrolled in longitudinal brain aging studies (n=292; 61% Female; 92% European American; mean age=69.6±7.7) completed evaluations including medical exams, neuroimaging, and sociodemographic surveys. Overweight/obese status defined as body mass index ≥30 kg/m2, and WMH load, captured by FLAIR images, as sum of deep and periventricular volumes, scored using the Fazekas scale (0-6), WMH≥4 considered high.

RESULTS

Logistic regression analyses, adjusted for age, sex, hypertension, and smoking history, indicated that age and interaction between race and obesity were significant predictors of WMH, demonstrating that obesity significantly moderated the relationship between race and WMH. Age independently increased the odds of high WMH by 16% (OR=1.16, 95% CI=1.09-1.23, p<0.001). Stratified analysis indicates that older European Americans had increased WMH (OR=1.17, 95% CI=1.09-1.23, p<0.001), while obese African Americans had increased WMH (OR=27.65, 95% CI=1.47-519.13, p<0.05). In a case controlled subgroup matched by age, sex, and education (n=48), African Americans had significantly higher WMH load (27% vs 4%, Χ 2=5.3, p=0.02).

CONCLUSION

Results denote that age predicted WMH among European Americans, while obesity predicted WMH among African Americans. Matched sample analyses indicate that obesity increases the odds of WMH, though more pronounced in African Americans. These findings suggest that obesity may explain the differential burden of white matter hyperintensity load, signifying public health and clinical importance.

Evaluation of Obesity Cutoff Values in Hispanic Adults: Derivation of New Standards

The diagnostic accuracy of clinical-based body composition methods such as body mass index (BMI), waist circumference (WC), bioimpedance analysis (BIA), and dual energy X-ray absorptiometry (DXA) has yet to be evaluated in Hispanic adults. Moreover, it has also been suggested that previously established obesity cutoff values may need adjusting.

PURPOSE

The primary aim of this study was to investigate the diagnostic accuracy of BMI, WC, BIA, and DXA for obesity classification in Hispanic adults. The secondary aim was to internally derive obesity cutoff values producing equal sensitivity and specificity for the respective tests.

METHODS

Hispanic females (n = 101) and males (n = 90) volunteered to participate in this study (18-45 years). Body fat percentage was estimated with BIA, DXA, and a 4-compartment (4C) model. Obesity-defined criteria was employed as follows: (Body fat percentage ≥ 25% and 35% and WC ≥ 102cm and 88cm for males and females, respectively; BMI ≥ 30 kg/m²). A 4C model was used as a criterion to evaluate BMI, WC, DXA, and BIA.

RESULTS

Sensitivity of DXA and BIA (74.1%-96.9%) was greater than BMI and WC (25.8%-51.9%) when using previously established standards. However, specificity was poor for DXA (<70%), but considered good to excellent for BMI, WC, and BIA (83.1%-96.6%) when using previously established standards. Internally derived cutoff values improved sensitivity for BMI and WC (74.2%-81.5%) and improved specificity for DXA (>80.0%).

CONCLUSION

The internally derived cutoff values, producing identical sensitivity, and specificity, were developed and shown to improve the diagnostic performance of the body composition methods compared to previously established obesity cutoff standards. Consequently, the internally derived obesity cutoff values are recommended for use by allied health professionals in clinical practice when equal sensitivity and specificity is desired.

Development of a Body Mass Index-based Body Fat Equation: Effect of Handgrip Strength

Body mass index (BMI)-based body fat equations from Womersley (BMIWOMERSLEY), Jackson (BMIJACKSON), Deurenberg (BMIDEURENBERG), and Gallagher (BMIGALLAGHER) are practical in clinical and field settings. However, research has shown these prediction equations produce large error, which may be due to the inability of BMI to account for differences in fat mass and fat-free mass. Thus, accounting for variations in muscular strength via relative handgrip (RHG) strength could help enhance the accuracy of a BMI-based body fat equation.

PURPOSE

The purpose of the current study was twofold: 1) to develop a new BMI-based body fat equation that includes the measurement of RHG (BMINICKERSON) and 2) to cross-validate BMINICKERSON, BMIWOMERSLEY, BMIJACKSON, BMIDEURENBERG, and BMIGALLAGHER against a four-compartment criterion.

METHODS

The development and cross-validation samples consisted of 230 and 110 participants, respectively. Criterion body fat percent was determined with a four-compartment model. RHG was calculated by summing the max of each handgrip strength measurement and dividing by body mass. BMI (kg·m), RHG (kg·kg), age (yr), ethnicity (Hispanic or non-Hispanic White), and sex (male or female) were entered into a stepwise regression to calculate BMINICKERSON.

RESULTS

BMINICKERSON was calculated as follows: body fat percent = 21.504 - (12.484 × RHG) - (7.998 × sex) + (0.722 × BMI). In the cross-validation sample, BMINICKERSON produced lower constant error (CE) and total error (TE) values (CE = -0.11%, TE = 4.28%) than all other BMI-based body fat equations (CE = 0.89%-1.90%, TE = 5.71%-6.87%). Furthermore, the 95% limits of agreement were lower for BMINICKERSON ± 8.47% than previous BMI-based body fat equations (95% limits of agreement = ±11.14% to 13.33%).

CONCLUSION

Current study results confirm that previous BMI-based body fat equations produce large error in Hispanics and non-Hispanic Whites but can be improved by accounting for RHG. Allied health professionals are encouraged to use BMINICKERSON in clinical and field settings for adiposity assessments.

Clinical Practice Guidelines for the Perioperative Nutrition, Metabolic, and Nonsurgical Support of Patients Undergoing Bariatric Procedures - 2019 Update: Cosponsored by American Association of Clinical Endocrinologists/American College of Endocrinology, The Obesity Society, American Society for Metabolic and Bariatric Surgery, Obesity Medicine Association, and American Society of Anesthesiologists

OBJECTIVE

The development of these updated clinical practice guidelines (CPGs) was commissioned by the American Association of Clinical Endocrinologists (AACE), The Obesity Society (TOS), American Society for Metabolic and Bariatric Surgery (ASMBS), Obesity Medicine Association (OMA), and American Society of Anesthesiologists (ASA) Boards of Directors in adherence with the AACE 2017 protocol for standardized production of CPGs, algorithms, and checklists.

METHODS

Each recommendation was evaluated and updated based on new evidence from 2013 to the present and subjective factors provided by experts.

RESULTS

New or updated topics in this CPG include: contextualization in an adiposity-based chronic disease complications-centric model, nuance-based and algorithm/checklist-assisted clinical decision-making about procedure selection, novel bariatric procedures, enhanced recovery after bariatric surgery protocols, and logistical concerns (including cost factors) in the current health care arena. There are 85 numbered recommendations that have updated supporting evidence, of which 61 are revised and 12 are new. Noting that there can be multiple recommendation statements within a single numbered recommendation, there are 31 (13%) Grade A, 42 (17%) Grade B, 72 (29%) Grade C, and 101 (41%) Grade D recommendations. There are 858 citations, of which 81 (9.4%) are evidence level (EL) 1 (highest), 562 (65.5%) are EL 2, 72 (8.4%) are EL 3, and 143 (16.7%) are EL 4 (lowest).

CONCLUSIONS

Bariatric procedures remain a safe and effective intervention for higher-risk patients with obesity. Clinical decision-making should be evidence based within the context of a chronic disease. A team approach to perioperative care is mandatory, with special attention to nutritional and metabolic issues.

Clinical practice guidelines for the perioperative nutrition, metabolic, and nonsurgical support of patients undergoing bariatric procedures - 2019 update: cosponsored by American Association of Clinical Endocrinologists/American College of Endocrinology, The Obesity Society, American Society for Metabolic & Bariatric Surgery, Obesity Medicine Association, and American Society of Anesthesiologists

OBJECTIVE

The development of these updated clinical practice guidelines (CPG) was commissioned by the American Association of Clinical Endocrinologists, The Obesity Society, the American Society of Metabolic and Bariatric Surgery, the Obesity Medicine Association, and the American Society of Anesthesiologists boards of directors in adherence to the American Association of Clinical Endocrinologists 2017 protocol for standardized production of CPG, algorithms, and checklists.

METHODS

Each recommendation was evaluated and updated based on new evidence from 2013 to the present and subjective factors provided by experts.

RESULTS

New or updated topics in this CPG include contextualization in an adiposity-based, chronic disease complications-centric model, nuance-based, and algorithm/checklist-assisted clinical decision-making about procedure selection, novel bariatric procedures, enhanced recovery after bariatric surgery protocols, and logistical concerns (including cost factors) in the current healthcare arena. There are 85 numbered recommendations that have updated supporting evidence, of which 61 are revised and 12 are new. Noting that there can be multiple recommendation statements within a single numbered recommendation, there are 31 (13%) Grade A, 42 (17%) Grade B, 72 (29%) Grade C, and 101 (41%) Grade D recommendations. There are 858 citations, of which 81 (9.4%) are evidence level (EL) 1 (highest), 562 (65.5%) are EL 2, 72 (8.4%) are EL 3, and 143 (16.7%) are EL 4 (lowest).

CONCLUSIONS

Bariatric procedures remain a safe and effective intervention for higher-risk patients with obesity. Clinical decision-making should be evidence-based within the context of a chronic disease. A team approach to perioperative care is mandatory with special attention to nutritional and metabolic issues.

The Prediction of Body Composition in African Americans From Spine and Hip Dual-Energy Absorptiometry

Body composition, the makeup of the body's fat and lean tissue, is associated with important health outcomes and provides useful clinical information. Although body composition can be measured with total body dual-energy X-ray absorptiometry (DXA), this is rarely performed. As an alternative to total body DXA measurement, methods for estimation of body composition have been developed. These methods use soft tissue measures from spine and hip DXA to predict body composition and include prediction equations previously published by Leslie and proprietary equations within General Electric densitometry software. However, these estimates have not been tested in African Americans (AA), an ethnicity with a different distribution of fat than Caucasians (CA). Therefore, we examined the performance of the existing models in 99 CA and 162 AA subjects over the age of 40 who had total body, spine, and hip DXA measurements. We observed that existing models estimated body composition well in CA but underestimated fat mass and overestimated lean mass in AA. AA subjects were then randomly divided into 2 equal-sized subgroups-the first to develop new prediction equations and the second to independently validate them. We found that body composition can be more accurately estimated using either a new model that we derived in AA subjects using backward stepwise elimination or by adding a fixed offset for AA to the previously published model. Our results demonstrate that body composition estimates from spine and hip DXA require consideration of race/ethnicity.

[Anthropometric measurements of general and central obesity and discriminative capacity on cardiovascular risk: RICARTO study]

INTRODUCTION AND OBJECTIVES

Overweight and obese patients have an increased risk of cardiovascular disease and general mortality. It is not clear which obesity index should be used in the clinic. The objective is to compare the relationship between body mass index (BMI), waist circumference (WC), waist-height ratio (WHR), and conicity index (Conicity-I) with 10-year Framingham cardiovascular risk (CVR).

MATERIAL AND METHODS

Population cross-sectional study in subjects ≥18years, residents in the Toledo (Spain) Health Area. Selection by random sampling. Measurements were made of the BMI, WC, and weight to height ratio with standardised methods. Framingham CVR. Calculation of AUC, and optimal cut-off points.

RESULTS

The study included 1,309 subjects, with mean age of 48.9±15.8years, and 55% women. The response rate was 36.6%. In women, the index that was best associated with CVR in women was the WC with an AUC=0.85 (95%CI: 0.81-0.88). In men it was the I-Conicity, with an AUC=0.81 (95%CI: 0.77-0.84). Cut points for BMI were similar in women (27.08kg/m²) and men (26.99kg/m²). The WC was lower in women (87.75cm) than in men (94.5cm). The WHR was higher in women (0.59) than in men (0.56). The I-Conicity was slightly lower in women (1.25) than in men (1.28). In women, all the ROC curves were closest to each other.

CONCLUSIONS

The central obesity indexes (WC and WHR) discriminated better than the BMI the CVR. In women, all the indices had greater AUCs than in men, except for the I-Conicity.

Body Mass Index and Decline in Cognitive Function in Older Black and White Persons

Background

While body mass index (BMI) is higher in black compared to white persons, little is known about BMI and change in cognition in cohorts with a large proportion of blacks. We examine relations of BMI with decline in global cognition and five cognitive domains, in older blacks and whites, and determine whether relations differ by race.

Methods

Participants were 2,134 persons without baseline dementia (33% black; 75% women; mean age =77.9 [range 53-100] and education = 14.7 years, Mini-Mental State Examination = 28.0), enrolled in one of two longitudinal, community-based cohort studies of aging (Minority Aging Research Study; Rush Memory and Aging Project). Summary scores of global cognition and five domains were based on 19 neuropsychological tests administered annually. Mixed-effects models, controlling for age, sex, education, and race, were used to examine the relation of baseline BMI to change in cognition.

Results

Baseline BMI = 28.4 units (30.3 in blacks [95% confidence interval (CI): 27.2-27.7]; 27.4 in whites [95% CI: 29.8-30.7]). During a mean annual follow-up of 6 years (SD = 4), lower baseline BMI was related to faster decline in global cognition (p = .002), and semantic memory (p < .001) and episodic memory (p = .004), but not working memory, perceptual speed, or visuospatial ability (all p > .08). The relationship of BMI with change in cognition was not modified by race (all p > .09).

Conclusions

Late-life lower BMI relates to faster rates of decline in cognition, specifically semantic memory and episodic memory, in both blacks and whites. The effect of BMI on cognition appears to be similar in both racial groups.

Association between stress fracture incidence and predicted body fat in United States Army Basic Combat Training recruits

Background

A stress fracture (SF) is a highly debilitating injury commonly experienced in United States Army Basic Combat Training (BCT). Body fat (BF) may be associated with this injury but previous investigations (in athletes) have largely used SF self-reports and lacked sufficient statistical power. This investigation developed an equation to estimate %BF and used that equation to examine the relationship between %BF and SF risk in BCT recruits.

Methods

Data for the %BF predictive equation involved 349 recruits with BF obtained from dual-energy X-ray absorptiometry. %BF was estimated using body mass index (BMI, weight/height²), age (yr), and sex in the entire population of BCT recruits over an 11-year period (n = 583,651). Medical information was obtained on these recruits to determine SF occurrence. Recruits were separated into deciles of estimated %BF and the risk of SFs determined in each decile.

Results

The equation was %BF = − 7.53 + 1.43 ● BMI + 0.13 ● age − 14.73 ● sex, with sex either 1 for men or 0 for women (r = 0.88, standard error of estimate = 4.2%BF). Among the men, SF risk increased at the higher and lower %BF deciles: compared to men in the mean %BF decile, the risk of a SF for men in the first (lowest %BF) and tenth (highest %BF) decile were 1.27 (95%confidence interval (95%CI) = 1.17–1.40) and 1.15 (95%CI = 1.05–1.26) times higher, respectively. Among women, SF risk was only elevated in the first %BF decile with risk 1.20 (95%CI = 1.09–1.32) times higher compared to the mean %BF decile.

Conclusions

Low %BF was associated with higher SF risk in BCT; higher %BF was associated with higher SF risk among men but not women.

Associations of overweight/obesity and socioeconomic status with hypertension prevalence across racial and ethnic groups

Racial/ethnic disparities in the prevalence of diagnosed hypertension are persistent but may be partially explained by racial/ethnic differences in weight category and neighborhood socioeconomic status. The authors compared hypertension prevalence rates among 4 060 585 adults with overweight or obesity across 10 healthcare systems by weight category and neighborhood education level in geographically and racially diverse individuals. Data were obtained from electronic health records. Hypertension was defined as at least two outpatient visits or one inpatient hospitalization with a coded diagnosis. Logistic regression, adjusted for age, sex, and site, with two-way interactions between race/ethnicity and weight category or neighborhood education, was used to examine the association between hypertension and race/ethnicity, with whites as the reference. Results documented that odds ratios for hypertension prevalence were greater for blacks, American Indians/Alaskan Natives, Asians, and Native Hawaiians/other Pacific Islanders compared with whites and lower for Hispanics in similar weight categories and neighborhood education levels. Although two-way interactions were statistically significant, the magnitude of the odds of hypertension compared with whites did not substantially vary across weight or neighborhood education. Hypertension odds were almost double relative to whites for blacks and Native Hawaiians/other Pacific Islanders across most weight categories and all neighborhood education levels. Odds of hypertension were about 50% greater for Asians relative to whites across weight categories. Results suggest that other factors might be associated with racial/ethnic disparities in hypertension. More research is needed to understand the many factors that may contribute to variation in diagnosed hypertension across racial/ethnic groups with overweight or obesity.

Different Associations of Trunk and Lower-Body Fat Mass Distribution with Cardiometabolic Risk Factors between Healthy Middle-Aged Men and Women

The aim of this study was to assess whether the gender-specific pattern of fat mass (FM) distribution is related to gender differences in cardiometabolic risk factors. 207 healthy middle-aged Japanese were included in the study. We measured FM in the total body, trunk, and lower-body with dual-energy X-ray absorptiometry (DXA). The percentage of trunk FM (TFM) and lower-body FM (LFM) is noted as %TFM and %LFM, respectively. Other measurements included glucose and insulin during oral glucose tolerance test (OGTT), leptin, adiponectin, plasminogen activator inhibitor-1 (PAI-1), tumor necrosis factor-α (TNF-α), C-reactive protein (CRP), and systemic oxidative stress marker. Arterial properties were indicated by cardio-ankle vascular index (CAVI) and intima-media thickness (IMT) of the common carotid artery. The results showed that %TFM is higher whereas %LFM is lower in men than in women and men have a more atherogenic cardiometabolic profile. In both genders, %TFM (%LFM) is related to an unfavorable (favorable) cardiometabolic profile. In particular, the relation between %LFM and OGTT-derived insulin sensitivity index is stronger in women than in men. These findings suggested that in relatively healthy adults, android and gynoid pattern of FM distribution contributes to gender differences in cardiometabolic risk factors.

Associations between physical activity and BMI, body fatness, and visceral adiposity in overweight or obese Latino and non-Latino adults

Background/Objectives

Although several studies have reported associations between moderate to vigorous physical activity (MVPA), body fatness, and visceral adipose tissue (VAT), the extent to which associations differ among Latinos and non-Latinos remains unclear. The present study evaluated the associations between body composition and MVPA in Latino and non-Latino adults.

Subjects/Methods

An exploratory, cross-sectional analysis was conducted using baseline data collected from 298 overweight adults enrolled in a 12-month randomized controlled trial that tested the efficacy of text messaging to improve weight loss. MVPA, body fatness and VAT were assessed by waist-worn accelerometry, DXA, and DXA-derived software (GE CoreScan GE, Madison, WI) respectively. Participants with less than 5 days of accelerometry data or missing DXA data were excluded; 236 participants had complete data. Multivariable linear regression assessed associations between body composition and MVPA per day, defined as time in MVPA, bouts of MVPA (time per bout ≥10 min), non-bouts of MVPA (time per bout <10 min), and meeting the 150-minute MVPA guideline. The modifying influence of ethnicity was modeled with a multiplicative interaction term.

Results

The interaction between ethnicity and MVPA in predicting percent body fat was significant (p = 0.01, 95% CI [0.58, 4.43]) such that a given increase in MVPA was associated with a greater decline in total body fat in non-Latinos compared to Latinos (adjusted for age, sex and accelerometer wear time). There was no interaction between ethnicity and MVPA in predicting VAT (g) (p = 0.78, 95% CI [−205.74, 273.17]) and BMI (p = 0.18, 95% CI [−0.49, 2.26]).

Conclusions

An increase in MVPA was associated with a larger decrease in body fat, but neither BMI nor VAT, in non-Latinos compared to Latinos. This suggests that changes in VAT and BMI in response to MVPA may be less influenced by ethnicity than is total body fatness.

Age-Related Changes in Segmental Body Composition by Ethnicity and History of Weight Change across the Adult Lifespan

This study assessed age-related changes in body composition (specifically in trunk fat and appendicular lean masses), with consideration of body mass index (BMI) at age 20 years (BMI reference age, “BMIref”), ethnicity and lifetime weight change history. A cross-sectional dual-energy X-ray absorptiometry-based dataset was extracted from the U.S. National Health and Nutrition Examination Survey (NHANES) 1999–2004. Only European-American and African-American subjects were used (2705 men, 2527 women). For each gender and ethnicity, 6 analytic cases were considered, based on three BMIref categories (normal, overweight and obese, being 22, 27 and 30 kg/m², respectively) and two weight contexts (stable weight or weight gain across the lifespan). A nonparametric model was developed to investigate age-related changes in body composition. Then, parametric modelling was developed for assessing BMIref- and ethnicity-specific effects during aging. In the stable weight, both genders’ and ethnicities’ trunk fat (TF) increased gradually; body fat (BF) remained stable until 40 years and increased thereafter; trunk lean (TL) remained stable, but appendicular lean (APL) and body lean (BL) declined from 20 years. In the weight gain context, TF and BF increased at a constant rate, while APL, TL and BL increased until 40–50 years, and then declined slightly. Compared with European-American subjects of both genders, African-American subjects had lower TF and BF masses. Ethnic differences in body composition were quantified and found to remain constant across the lifespan.

Trabecular bone scores and lumbar spine bone mineral density of US adults: comparison of relationships with demographic and body size variables

This study examines demographic patterns and body size relationships in trabecular bone score and lumbar spine BMD of US adults from NHANES 2005-2008.

INTRODUCTION

Limited data exist on demographic and body size relationships for trabecular bone score (TBS), a new variable derived from bone texture analysis of lumbar spine dual-energy X-ray absorptiometry (DXA) scans. This study compares demographic patterns and correlations with body size (body mass index (BMI), weight, waist circumference, total body fat, trunk fat, trunk lean) between TBS and lumbar spine bone mineral density (LSBMD) for adults age ≥20 years from the National Health and Nutrition Examination Survey (NHANES) 2005-2008 with BMI in the optimal range for TBS (15-37 kg/m(2)).

METHODS

LSBMD, TBS, body fat, and lean were obtained by DXA. Weight, height, and waist circumference were measured. BMI was calculated from height and weight.

RESULTS

Sex differences in TBS varied by age and race/ethnicity (p sex X age interaction and p sex X race/ethnicity interaction < 0.001). In most of the nine demographic subgroups examined, TBS did not differ by sex (four subgroups) or was significantly higher in women (three subgroups). TBS differences by race/ethnicity were inconsistent in men; in women, non-Hispanic whites (NHWs) had higher TBS than non-Hispanic blacks (NHBs) or Mexican Americans (MAs) in all age groups. In contrast, LSBMD was either significantly higher in men (five subgroups) or did not differ by sex (four subgroups). Race/ethnic differences in LSBMD were consistent across age and sex (NHB > NHW > MA). All body size variables were negatively related to TBS but positively related to LSBMD.

CONCLUSIONS

Demographic patterns and body size relationships differed between TBS and LSBMD.

Long term trends and racial/ethnic disparities in the prevalence of obesity

Obesity is an epidemic associated with higher rates of hypertension, diabetes, and cardiovascular diseases. However, significant racial disparities in the prevalence of obesity have been reported. To evaluate racial disparities and trends in the prevalence of obesity and obesity-related diseases. A population-based retrospective cohort study utilized data from the 1985 to 2011 California Behavioral Risk Factor Survey. Trends in obesity prevalence were stratified by age, sex, race/ethnicity, and socioeconomic factors. Multivariate logistic regression models evaluated independent predictors of obesity. The prevalence of obesity in significantly increased from 1985 to 2011 (8.6 vs. 22.8%, p < 0.001). This increase was seen among men and women, and among all race/ethnic, age, and socioeconomic groups. Hypertension and diabetes also increased during this time period (hypertension 20.7-35.9%; diabetes 4.2-11.2%). Obesity prevalence was highest in blacks and Hispanics, and lowest in Asians (blacks 33.3%; Hispanics 28.8%; Asians 9.0%; p < 0.001). Obesity prevalence was associated with lower education level, lower income, and unemployment status. After adjustments for age, sex, co morbidities, and surrogates of socioeconomic status, the increased risk of obesity in blacks and Hispanics persisted (blacks OR 1.51; Hispanics OR 1.18), whereas Asians were less likely to be obese (OR 0.37). While the overall prevalence of obesity increased from 1985 to 2011, significant racial/ethnic disparities in obesity have developed, with the highest prevalence seen in blacks and Hispanics, and the lowest seen in Asians.

The Impact of Educational Attainment on Observed Race/Ethnic Disparities in Inflammatory Risk in the 2001-2008 National Health and Nutrition Examination Survey

Inflammation has shown to be an independent predictor of cardiovascular disease (CVD) and growing evidence suggests Non-Hispanic Blacks (NHBs) and certain Hispanic subgroups have higher inflammation burden compared to Non-Hispanic Whites (NHWs). Socioeconomic status (SES) is a hypothesized pathway that may account for the higher inflammation burden for race/ethnic groups yet little is known about the biological processes by which SES “gets under the skin” to affect health and whether income and education have similar or distinct influences on elevated inflammation levels. The current study examines SES (income and education) associations with multiple levels of C-Reactive Protein (CRP), an important biomarker of inflammation, in a sample of 13,362 NHWs, 7696 NHBs and 4545 Mexican Americans (MAs) in the United States from the 2001 to 2008 National Health and Nutrition Examination Survey. After adjusting for age, sex, and statin use, NHBs and MAs had higher intermediate and high CRP levels compared to NHWs. Income lessened the magnitude of the association for both race/ethnic groups. The greater intermediate and high CRP burden for NHBs and MAs was strongly explained by educational attainment. MAs were more vulnerable to high CRP levels for the lowest (i.e., less than nine years) and post high school (i.e., associates degree) educational levels. After additional adjustment for smoking, heavy drinking, high waist circumference, high blood pressure, diabetes and statin use, the strength of the association between race/ethnicity and inflammation was reduced for NHBs with elevated intermediate (RR = 1.31; p ≤ 0.001) and high CRP levels (RR = 1.14; p ≤ 0.001) compared to NHWs but the effect attenuated for MAs for both intermediate (RR = 0.74; p ≤ 0.001) and high CRP levels (RR = 0.38; p ≤ 0.001). These findings suggest educational attainment is a powerful predictor of elevated CRP levels in race/ethnic populations and challenges studies to move beyond examining income as a better predictor in the SES-inflammation pathway.

Is waist circumference per body mass index rising differentially across the United States, England, China and Mexico?

BACKGROUND/OBJECTIVES

Little is known about whether waist circumference (WC) has increased disproportionately relative to body mass index (BMI) around the world.

SUBJECTS/METHODS

Data came from the US National Health and Nutrition Examination Survey (1988-1994 and 2007-2010), Health Survey for England (1992-1993 and 2008-2009); the Mexican Nutrition Survey (1999) and the Mexican National Health and Nutrition Survey (NHNS 2012); and the China Health and Nutrition Survey (1993 and 2011). Country- and sex-stratified (for the United States, also race-/ethnicity-stratified) multivariable linear regressions were used to estimate mean difference in WC over time relative to BMI at specified overweight and obesity cutoff points, adjusting for age and survey year.

RESULTS

Although mean WC and BMI shifted upward over time in all age-sex subpopulations in all four countries, trends in overweight prevalence were less consistent. However, WC relative to BMI increased at varying magnitudes across all countries and subpopulations, except US Black men. The magnitude of increase was largest for women in the youngest age group (20-29 years), particularly for women in Mexico (+6.6 cm, P<0.0001) and China (+4.6 cm, P<0.0001) (holding BMI constant at 25 kg/m(2)). For men, the increase was primarily evident among Chinese men (+4.8 cm, P<0.0001).

CONCLUSIONS

WC has increased disproportionately over time relative to overall body mass across the United States, England, Mexico and China, particularly among young women, with the largest increases occurring in the middle-income countries of Mexico and China. These patterns are potentially a cause for concern especially for countries undergoing rapid economic and nutritional transitions.

Type II diabetes disparities in diverse women: the potential roles of body composition, diet and physical activity

The rates of diabetes in the USA are rapidly increasing, and vary widely across different racial/ethnic groups. This paper explores the potential contribution of body composition, diet and physical activity in explaining diabetes disparities across women of different racial and ethnic backgrounds. For body composition, racial/ethnic groups differ widely by BMI, distribution of body mass and quantity and type of adipose tissue. Dietary patterns that vary across race/ethnicity include consumption of meat, added sugars, high-glycemic carbohydrates and fast food. Additionally, physical activity patterns of interest include aerobic versus muscle-strengthening exercises, and the purpose of physical activity (leisure, occupation, or transportation). Overall, these variables provide a partial picture of the source of these widening disparities, and could help guide future research in addressing and reducing diabetes disparities.

Risk of Mortality According to Body Mass Index and Body Composition Among Postmenopausal Women

Obesity, often defined as a body mass index (BMI; weight (kg)/height (m)(2)) of 30 or higher, has been associated with mortality, but age-related body composition changes can be masked by stable BMI. A subset of Women's Health Initiative participants (postmenopausal women aged 50-79 years) enrolled between 1993 and 1998 who had received dual-energy x-ray absorptiometry scans for estimation of total body fat (TBF) and lean body mass (LBM) (n = 10,525) were followed for 13.6 (standard deviation, 4.6) years to test associations between BMI, body composition, and incident mortality. Overall, BMI ≥35 was associated with increased mortality (adjusted hazard ratio (HR) = 1.45, 95% confidence interval (CI): 1.16, 1.82), while TBF and LBM were not. However, an interaction between age and body composition (P < 0.001) necessitated age stratification. Among women aged 50-59 years, higher %TBF increased risk of death (HR = 2.44, 95% CI: 1.38, 4.34) and higher %LBM decreased risk of death (HR = 0.41, 95% CI: 0.23, 0.74), despite broad-ranging BMIs (16.4-69.1). However, the relationships were reversed among women aged 70-79 years (P < 0.05). BMI did not adequately capture mortality risk in this sample of postmenopausal women. Our data suggest the clinical utility of evaluating body composition by age group to more robustly assess mortality risk among postmenopausal women.

Obesity and reproduction: a committee opinion

The purpose of this ASRM Practice Committee report is to provide clinicians with principles and strategies for the evaluation and treatment of couples with infertility associated with obesity. This revised document replaces the Practice Committee document titled, "Obesity and reproduction: an educational bulletin," last published in 2008 (Fertil Steril 2008;90:S21-9).

Indices of adiposity and thyroid hormones in euthyroid postmenopausal women

OBJECTIVE

We aimed to evaluate the association between thyroid hormones and indices of obesity in a sample of euthyroid postmenopausal women.

DESIGN

Cross-sectional study.

METHODS

Serum levels of TSH, free triiodothyronine (FT3), and free thyroxine (FT4) as well as BMI and waist:hip ratio (WHR) were evaluated in 194 healthy euthyroid postmenopausal women. Ultrasonography was used to assess abdominal fat layers (subcutaneous fat (SF), preperitoneal fat (PF), and SF:PF ratio). Indices of adiposity were defined as high vs low depending on the median value of the assessed parameters.

RESULTS

After multivariate adjustment for traditional risk factors, lower FT4 levels and a higher FT3:FT4 ratio predicted higher SF mass (FT4, Exp(β)=0.035, P=0.020 and FT3:FT4, Exp(β)=2.374, P=0.018), whereas higher FT3 predicted higher PF mass (Exp(β)=2.815, P=0.032). Women with FT3:FT4 above the highest quartile had a significantly higher SF mass as compared to women in the lowest quartile (1.81 ± 0.62 cm vs 1.54 ± 0.46 cm, P=0.027). BMI had a positive independent association with TSH (Exp(β)=1.829, P=0.018). Finally, FT3 was significantly associated with SF mass among women with higher BMI (FT3, β=0.259, P=0.040) and women with higher WHR (β=0.309, P=0.020) but not among women with lower BMI or WHR values.

CONCLUSION

Thyroid hormone levels, and in particular FT3, were independently associated with SF and PF in euthyroid postmenopausal women, and this association was mainly evident in women with higher BMIs. On the other hand, among traditional indices of adiposity, only TSH was positively associated with BMI. Larger prospective studies are needed to evaluate the significance of the present findings.

The Interplay Between Sex, Ethnicity, and Adipose Tissue Characteristics

The obesity epidemic in the USA affects disproportionately women and the ethnic minorities. On the other hand, female sex is traditionally associated with a favorable fat distribution preferentially in the subcutaneous depots of the lower body and with improved endocrine and metabolic function of the adipose tissue. However, these data are derived from predominantly non-Hispanic white populations. This review discusses fat distribution patterns in women of diverse ethnic backgrounds, together with data on the release of adipokines from adipose tissue in these populations. Very little information is available on how the metabolic function of the adipocyte differs depending on ethnicity. Thus, it becomes clear that future clinical and translational research should explicitly discuss and take into account the sex and ethnic background of the populations studied.

Differences in skull base thickness in patients with spontaneous cerebrospinal fluid leaks

BACKGROUND

This study was designed to determine if differences in overall skull base thickness exist in patients with spontaneous cerebrospinal fluid (SCSF) leaks and to compare our institution's 10-year experience with the endoscopic repair of these leaks to the existing literature. A retrospective cohort study was performed in a tertiary rhinologic practice.

METHODS

A retrospective study by two blinded independent reviewers compared the skull base thickness on computerized tomography (CT) imaging in our SCSF leak patients to nonleaking controls and patients with traumatic CSF leaks. Surgical outcomes were compared with a pooled analysis of the published literature.

RESULTS

SCSF leaks were seen most commonly in obese, middle-aged women of African American descent. SCSF leak patients were shown to have thinner skull bases in the region of the ethmoid roof, lateral lamella, and anterior face of the sella (p < 0.05) compared with patients with traumatic leaks and nonleaking controls. No racial difference in skull base thickness was observed when patients were matched according to leak type. The success rate of primary endoscopic intervention in our patients was high at 94% and comparable with the published literature.

CONCLUSION

Differences in skull base thickness exist in SCSF patients, but whether this predisposes to such leaks or is a consequence of the underlying pathophysiology remains unknown. The endoscopic endonasal approach provides a highly effective means of repairing such leaks with success rates comparable with the endoscopic repair of other leak types. Adjuvant measures including weight reduction, lumbar drain, and acetazolamide use may increase success rates and should be considered in their management.

Body fat percentage, body mass index and waist-to-hip ratio as predictors of mortality and cardiovascular disease

OBJECTIVE

To study the utility of body fat percentage in predicting health outcomes when other obesity indices are considered.

METHODS

We conducted a prospective cohort study to evaluate the independent utility of body fat percentage and other obesity indices in predicting mortality and cardiovascular disease (CVD).

RESULTS

We prospectively followed 15 062 European Prospective Investigation into Cancer (EPIC)-Norfolk participants who attended a health examination during 1997–2000 for all-cause mortality and incidence of CVD up to end of December 2011 and end of March 2009, respectively. During the follow-up, 2420 died and 4665 had incident CVD. After exclusion of prior stroke, myocardial infarction and cancer and adjusting for potential confounders, body mass index (BMI) and waist-to- hip ratio (WHR), the HR of mortality for men were 0.86 (0.68 to 1.09), 0.81 (0.61 to 1.07) and 0.76 (0.55 to 1.05) and for women were 0.91 (0.70 to 1.17), 0.75 (0.55 to 1.02) and 0.87 (0.61 to 1.23) for second, third and fourth quartile compared with the first (bottom) quartile of body fat percentage. The respective HRs for incident CVD were 0.99 (0.83 to 1.19), 0.85 (0.69 to 1.04) and 0.81 (0.64 to 1.03) for men and 0.98 (0.82 to 1.17), 0.89 (0.73 to 1.10) and 1.02 (0.81 to 1.29) for women. In contrast, higher BMI and WHR were associated with an increased risk of both outcomes and WHR appeared to have the best predictive value among three indices.

CONCLUSIONS

Once BMI and WHR are taken into account, fat percentage does not add to prediction of mortality or CVD in middle-aged and older-aged adults.

Socioeconomic Status, Smoking, Alcohol use, Physical Activity, and Dietary Behavior as Determinants of Obesity and Body Mass Index in the United States: Findings from the National Health Interview Survey

OBJECTIVES

The aim of this research was to study the socio-demographic and behavioral determinants of obesity and Body Mass Index (BMI) in the United States, using a nationally representative sample.

METHODS

We used data from the 2010 US National Health Interview Survey. Analyses were limited to adults 18 years and older (N=23,434). Multivariate regression analyses were conducted to estimate the associations between covariates and obesity and BMI.

RESULTS

Overall, 28.1% in the sample were obese and the mean BMI was 27.6 kg/m(2). In adjusted models, we found that older age, non-Hispanic Black race, lower education and income levels, Midwestern and Southern region of residence, former smoking, infrequent alcohol use, physical inactivity, consumption of less fruits, vegetables, brown rice and more cheese, fried potato and meat, were associated with obesity. These factors were also associated with higher BMI, along with male gender and higher consumption of meat, fried potatoes and cheese.

CONCLUSIONS AND GLOBAL HEALTH IMPLICATIONS

The association of many of the socio-demographic and behavioral factors with obesity and higher BMI found in our study was consistent with previous findings. Persistence of such associations suggest a need for better understanding of the underlying mechanism as well as for evaluation of the current programs and policies targeted at reducing the obesity burden in the United States. In view of the rising global obesity epidemic, especially in the low- and middle-income countries, our findings could help guide development of effective health and social policies and programs aimed at reducing the obesity burden in other parts of the world.

Ethnic disparities in the association of body mass index with the risk of hypertension and diabetes

Despite having lower body mass index (BMI) compared to other ethnic groups, Asians continue to develop significant metabolic diseases such as hypertension and diabetes. To evaluate the disparate association of BMI and risk of hypertension and diabetes in Asians. We retrospectively studied 150,753 adults from the 1985-2011 California Behavioral Risk Factor Survey. Trends in prevalence of obesity, hypertension, and diabetes were stratified by ethnicity. Multivariate logistic regression models evaluated the incremental effect of one unit BMI increase on risk of hypertension and diabetes and the disparate risks of hypertension and diabetes at different BMI thresholds. Asians had the lowest BMI among all groups. However, the impact of increasing BMI on risk of hypertension and diabetes was significantly greater in Asians. For each one unit increase in BMI, Asians were significantly more likely to have hypertension (OR 1.15; 95% CI 1.13-1.18) compared to non-Hispanic whites, blacks, and Hispanics. Similar trends were seen for diabetes (Asians: OR 1.15; 95% CI 1.13-1.18). The risk of hypertension in Asians with BMI ≥ 22 was similar to non-Hispanic whites with BMI ≥ 27 and blacks with BMI ≥ 28. The risk of diabetes in Asians with BMI ≥ 28 was similar to non-Hispanic whites with BMI ≥ 30. Despite lower overall BMI compared to other groups, weight gain in Asians is associated with significantly higher risks of hypertension and diabetes. Compared to other ethnic groups, similar risks of hypertension and diabetes are seen in Asians at much lower BMI.

Lifecourse socioeconomic position and 16 year body mass index trajectories: differences by race and sex

OBJECTIVE

The aim of this study is to evaluate the association between lifecourse socioeconomic position (SEP) and changes in body mass index (BMI), and assess disparities in these associations across racial/ethnic groups.

METHODS

With longitudinal data from 4 waves of the Americans' Changing Lives Study (1986-2002), we employed mixed-effects modeling to estimate BMI trajectories for 1174 Blacks and 2323 White adults. We also estimated associations between these trajectories and lifecourse SEP variables, including father's education, perceived childhood SEP, own education, income, wealth, and financial security.

RESULTS

Blacks had higher baseline BMIs, and steeper increases in BMI, compared to Whites. Childhood SEP, as measured by high father's education, was associated with lower baseline BMI among Whites. High education was associated with a lower baseline BMI within both race and sex categories. Income had contrasting effects among men and women. Higher income was associated with higher BMI only among males. Associations between indicators of SEP and BMI trajectories were only found for Whites.

CONCLUSIONS

Our study demonstrates that lifecourse SEP may influence adult BMI differently within different racial and sex groups.

Change in daily energy intake associated with pairwise compositional change in carbohydrate, fat and protein intake among US adults, 1999-2010

OBJECTIVE

To assess the change in daily energy intake associated with pairwise compositional change in carbohydrate, fat and protein intake among US adults stratified by sex, race/ethnicity and weight status.

DESIGN

Linear mixture model was performed to estimate the relationship between daily energy intake and macronutrient composition, adjusted for age and alcohol consumption, and accounting for survey design.

SETTING

Study sample from the National Health and Nutrition Examination Survey, 1999-2010 waves.

SUBJECTS

A total of 27 589 US adults aged 20 years and older were included in the study. Dietary macronutrient intake was calculated from 24 h dietary recall and BMI from objectively measured weight/height.

RESULTS

Across all population subgroups, substituting protein or carbohydrate for fat and substituting protein for carbohydrate were associated with decreased daily energy intake, with the largest effect resulting from substituting protein for fat. A 1 % increase in the percentage of energy from protein substituted for a 1 % decrease in the percentage of energy from fat was associated with a decrease in daily energy intake of 268.2 (95 % CI 169.0, 367.4) kJ, 289.5 (95 % CI 215.9, 363.2) kJ and 293.7 (95 % CI 210.0, 377.4) kJ among normal-weight (18.5≤BMI, kg/m2<25.0), overweight (25.0≤BMI, kg/m2<30.0) and obese (BMI≥30.0 kg/m2) men, and 177.4 (95 % CI 130.5, 224.3) kJ, 188.7 (95 % CI 139.3, 238.1) kJ and 204.2 (95 % CI 158.2, 250.2) kJ among normal-weight, overweight and obese women, respectively. The relationship between macronutrient composition and daily energy intake varied substantially across sex, race/ethnicity and weight status.

CONCLUSIONS

Policies promoting higher daily protein intake at the expense of lower fat intake could be effective in reducing total energy intake among US adults.

Accuracy of body fat percent and adiposity indicators cut off values to detect metabolic risk factors in a sample of Mexican adults

Background

Although body fat percent (BF%) may be used for screening metabolic risk factors, its accuracy compared to BMI and waist circumference is unknown in a Mexican population. We compared the classification accuracy of BF%, BMI and WC for the detection of metabolic risk factors in a sample of Mexican adults; optimized cutoffs as well as sensitivity and specificity at commonly used BF% and BMI international cutoffs were estimated. We also estimated conditional BF% means at BMI international cutoffs.

Methods

We performed a cross-sectional analysis of data on body composition, anthropometry and metabolic risk factors(high glucose, high triglycerides, low HDL cholesterol and hypertension) from 5,100 Mexican men and women. The association between BMI, WC and BF%was evaluated with linear regression models. The BF%, BMI and WC optimal cutoffs for the detection of metabolic risk factors were selected at the point where sensitivity was closest to specificity. Areas under the ROC Curve (AUC) were compared among classifiers using a non-parametric method.

Results

After adjustment for WC, a 1% increase in BMI was associated with a BF% rise of 0.05 percentage points (p.p.) in men (P < 0.05) and 0.25 p.p. in women (P < 0.001). At BMI = 25.0 predicted BF% was 27.6 ± 0.16 (mean ± SE) in men and 41.2 ± 0.07 in women. Estimated BF% cutoffs for detection of metabolic risk factors were close to 30.0 in men and close to 44.0 in women. In men WC had higher AUC than BF% for the classification of all conditions whereas BMI had higher AUC than BF% for the classification of high triglycerides and hypertension. In womenBMI and WC had higher AUC than BF% for the classification of all metabolic risk factors.

Conclusions

BMI and WC were more accurate than BF% for classifying the studied metabolic disorders. International BF% cutoffs had very low specificity and thus produced a high rate of false positives in both sexes.

Body mass index modulates blood pressure heritability: the Family Blood Pressure Program

BACKGROUND

Candidate gene and twin studies suggest that interactions between body mass index (BMI) and genes contribute to the variability of blood pressure (BP). To determine whether there is evidence for gene-BMI interactions, we investigated the modulation of BP heritability by BMI using 4,153 blacks, 1,538 Asians, 4,013 whites, and 2,199 Hispanic Americans from the Family Blood Pressure Program.

METHODS

To capture the BP heritability dependence on BMI, we employed a generalized variance components model incorporating linear and Gaussian interactions between BMI and the genetic component. Within each race and network subgroup, we used the Akaike information criterion and likelihood ratio test to select the appropriate interaction function for each BP trait (systolic BP (SBP), diastolic BP (DBP), mean arterial pressure (MAP), and pulse pressure (PP)) and determine interaction significance, respectively.

RESULTS

BP heritabilities were significantly modified by BMI in the GenNet and SAPPHIRe Networks, which contained the youngest and least-obese participants, respectively. GenNet Whites had unimodal SBP, MAP, and PP heritabilities that peaked between BMI values of 33 and 37kg/m(2). The SBP and MAP heritabilities in GenNet Hispanic Americans, as well as the PP heritability in GenNet blacks, were increasing functions of BMI. The DBP and SBP heritabilities in the SAPPHIRe Chinese and Japanese, respectively, were decreasing functions of BMI.

CONCLUSIONS

BP heritability differed by BMI in the youngest and least-obese networks, although the shape of this dependence differed by race. Use of nonlinear gene-BMI interactions may enhance BP gene discovery efforts in individuals of European ancestry.

Prevalence and Trends of Adult Obesity in the US, 1999-2012

Aim. To provide national estimates of obesity among US adults aged 20 years and older in 2011-2012 and track its trends from 1999 to 2012. Methods. Measured weight/height from National Health and Nutrition Examination Survey 1999-2012 waves was used to calculate body mass index (BMI) and prevalence measures. Piecewise logistic regressions were conducted to test the differential trends before and after 2010. Results. In 2011-2012, the age-adjusted prevalence of overweight and obesity combined (BMI ≥ 25) was 71.1% (95% CI: 68.0%-74.2%) among men and 65.5% (61.8%-69.3%) among women, and the prevalence of obesity (BMI ≥ 30) was 33.3% (30.5%-36.2%) among men and 35.8% (32.3%-39.4%) among women. From 1990-2000 to 2009-2010, the prevalence of overweight and obesity combined, obesity, grades 2 and 3 obesity combined (BMI ≥ 35), and grade 3 obesity (BMI ≥ 40) increased by 7.2%, 17.8%, 17.6%, and 33.0%, respectively. Compared to 2009-2010, most gender- and race/ethnicity-specific prevalence measures remained unchanged or slightly decreased in 2011-2012. No significant difference in trends among prevalence measures was found before and after 2010. Conclusions. Concurrent evidence on the leveling off of obesity in the US is thin. Given its high prevalence and profound socioeconomic consequences, close monitoring of the trend is warranted.

General medical burden in bipolar disorder: findings from the LiTMUS comparative effectiveness trial

OBJECTIVE

This study examined general medical illnesses and their association with clinical features of bipolar disorder.

METHOD

Data were cross-sectional and derived from the Lithium Treatment - Moderate Dose Use Study (LiTMUS), which randomized symptomatic adults (n = 264 with available medical comorbidity scores) with bipolar disorder to moderate doses of lithium plus optimized treatment (OPT) or to OPT alone. Clinically significant high and low medical comorbidity burden were defined as a Cumulative Illness Rating Scale (CIRS) score ≥4 and <4 respectively.

RESULTS

The baseline prevalence of significant medical comorbidity was 53% (n = 139). Patients with high medical burden were more likely to present in a major depressive episode (P = .04), meet criteria for obsessive-compulsive disorder (P = .02), and experience a greater number of lifetime mood episodes (P = 0.02). They were also more likely to be prescribed a greater number of psychotropic medications (P = .002). Sixty-nine per cent of the sample was overweight or obese as defined by body mass index (BMI), with African Americans representing the racial group with the highest proportion of stage II obesity (BMI ≥35; 31%, n = 14).

CONCLUSION

The burden of comorbid medical illnesses was high in this generalizable sample of treatment-seeking patients and appears associated with worsened course of illness and psychotropic medication patterns.

Exploring risk factors in Latino cardiovascular disease: the role of education, nativity, and gender

OBJECTIVES

We examined 3 cardiovascular disease risk factors by nativity and gender, evaluating evidence for education and health behaviors in explaining the "Hispanic Health Paradox."

METHODS

We analyzed 2001-2008 National Health and Nutrition Examination Survey data for adults (n = 6032) to compare hypertension, high waist circumference, and diabetes for US- and foreign-born Mexican men and women. We controlled for age, depression, and health insurance.

RESULTS

Cardiovascular disease risk factors differed by education, nativity, and gender. Higher education was associated with higher odds of hypertension and high waist circumference for men and women regardless of nativity. As education increased, the odds of diabetes increased for US-born women, showing a gradient for this population. Finally, foreign-born Mexican women with 5 to 19 years in the United States conferred the highest odds of having diabetes, whereas foreign-born men with less than 5 years in the United States had the lowest odds for high waist circumference and presence of diabetes.

CONCLUSIONS

Results contest assumptions of the Hispanic Health Paradox and suggest new approaches. New research can yield accurate information to ensure the development of appropriate interventions, decreasing health disparities endemic to a subgroup of Latinos.

The obesity pattern of idiopathic intracranial hypertension in men

BACKGROUND

Idiopathic intracranial hypertension (IIH), also known as pseudotumor cerebri, is a disorder of unknown etiology, predominantly affecting obese women of childbearing age. IIH is uncommon in men, with a reported female-to-male ratio of 8:1. The pathogenesis of IIH is poorly understood. Several mechanisms have been suggested, but no one mechanism has been able to account for all manifestations of the disease. This research aims to characterize the obesity phenotype(s) of men with IIH in order to find potential inducers for this disease.

METHODS

This is a cross-sectional study based on subjects' medical records. It compared anthropometric parameters between 22 men with IIH, 60 healthy men, and 44 females with IIH. One-way analysis with age and body mass index included as covariates was applied for the assessment of the difference in fat distribution among the three groups.

RESULTS

No significant differences were observed between the male IIH cohort and healthy males for age, BMI, and waist measurements, whereas hip circumference was significantly larger in the IIH cohort (114 ± 13 vs. 104 ± 16 cm; respectively, p < 0.001). Consequently, waist-to-hip ratio (WHR) was significantly lower in the male IIH cohort (0.88 ± 0.08 vs. 0.95 ± 0.12; p < 0.001). While no significant differences were observed for age and hip measurements between male IIH and female IIH cohorts, waist circumference and waist-to-hip ratio (WHR) were significantly larger in the male cohort (102 ± 19 cm vs. 95 ± 13 cm, p < 0.001; 0.88 ± 0.08 vs. 0.78 ± 0.06, p < 0.001, respectively). All these results maintained after adjustment for age and BMI.

CONCLUSIONS

This is the first report of body fat distribution patterns in men with IIH. Whereas male IIH have larger central fat deposition than female IIH patients, abdominal fatness is less accentuated in IIH men compared to normal obese men. The later observation is in agreement with similar results regarding female IIH patients. We believe that these findings justify further investigation into the involvement of various fat depots in the pathogenesis of IIH in men and women alike.

Absolute wealth and world region strongly predict overweight among women (ages 18-49) in 360 populations across 36 developing countries

This paper proposes a benchmark for comparing SES gradients across countries, based on gross domestic product apportioned to members of differing wealth categories within countries. Using this approach, we estimate absolute wealth in 360 populations in 36 developing countries and model its relationship with overweight (BMI≥25) among non-pregnant women ages 18-49. A simple model based on absolute wealth alone strongly predicts odds of overweight (R(2)=0.59), a relationship that holds both between countries and between different groups in the same country (10 populations for each of 36 countries). Moreover, world region modifies this relationship, accounting for an additional 22% of variance (R(2)=0.81). This allows us to extract a basic pattern: rising rates of overweight in lower and middle income countries closely track increasing economic resources, and the shape of that gradient differs by region in systematic ways.

Cardiometabolic risks during anabolic hormone supplementation in older men

OBJECTIVE

To determine the cardiometabolic risks of testosterone and growth hormone (GH) replacement therapy to youthful levels during aging.

DESIGN AND METHODS

A double-masked, partially placebo controlled study in 112 men 65-90 years-old was conducted. Transdermal testosterone (5 g vs. 10 g/day) using a Leydig Cell Clamp and subcutaneous recombinant GH (rhGH) (0 vs. 3 vs. 5 μg/kg/day) were administered for 16-weeks. Measurements included testosterone and IGF-1 levels, body composition by DEXA, and cardiometabolic risk factors (upper body fat, blood pressure, insulin sensitivity, fasting triglycerides, HDL-cholesterol, and serum adiponectin) at baseline and after 16 weeks of treatment.

RESULTS

Some cardiometabolic factors improved (total and trunk fat, triglycerides, HDL-cholesterol) and others worsened (systolic blood pressure, insulin sensitivity index [QUICKI], adiponectin). Cardiometabolic risk composite scores (CRCSs) improved (-0.69 ± 1.55, P < 0.001). In multivariate analyses, QUICKI, triglycerides, and HDL-cholesterol contributed 33%, 16%, and 14% of the variance in CRCS, respectively. Pathway analyses indicated that changes in fat and lean mass were related to individual cardiometabolic variables and CRCS in a complex manner. Changes in BMI, reflecting composite effects of changes in fat and lean mass, were more robustly associated with cardiometabolic risks than changes in fat mass or LBM individually.

CONCLUSIONS

Testosterone and rhGH administration was associated with diverse changes in individual cardiometabolic risk factors, but in aggregate appeared not to worsen cardiometabolic risk in healthy older men after 4-months. The long-term effects of these and similar anabolic therapies on cardiovascular events should be investigated in populations with greater functional limitations along with important health disabilities including upper body obesity and other cardiometabolic risks.

Ethnic variability in adiposity, thrifty phenotypes and cardiometabolic risk: addressing the full range of ethnicity, including those of mixed ethnicity

Ethnic groups vary in cardiometabolic risk, but the underlying mechanisms remain unclear. Several components of body composition variability (fat/lean ratio, fat distribution, lean mass composition and metabolism, and adipose tissue biology) are increasingly linked with cardiometabolic risk and vary substantially across ethnic groups. Constituents of lean mass are proposed to contribute to 'metabolic capacity', a generic trait favouring the maintenance of homeostasis. Adiposity is proposed to contribute to 'metabolic load', which at higher levels challenges metabolic homeostasis, elevating cardiometabolic risk. Ethnic differences in body composition, representing different load-capacity ratios, may therefore contribute to ethnic variability in cardiometabolic risk. Ecological and evolutionary factors potentially contributing to ethnic variability in body composition are explored. In contemporary populations, clinicians encounter an increasing range of ethnicity, along with many individuals of mixed-ethnic ancestry. Increasing understanding of the contribution of body composition to cardiometabolic risk may reduce the need to treat ethnic groups as qualitatively different. A conceptual model is proposed, treating insulin sensitivity and stroke risk as composite functions of body composition variables. Operationalizing this model may potentially improve the ability to assess cardiovascular risk across the full ethnicity spectrum, and to predict cardiometabolic consequences of excess weight gain.

Implications of weight and body mass index for plasma donation and health

This study determined the percentage of potential plasma donors who could donate plasma in the 3 allowable plasma volume limit categories as specified by the Food and Drug Administration (FDA), as well as the association of the body mass index (BMI) of these individuals with age, blood pressure, oral temperature, and pulse. Of 315 plasma donors analyzed, 107 (34.0%) weighed between 110 and 149 lbs (50.0-67.7 kg), 89 (28.2%) weighed between 150 and174 lbs (68.2-79.1 kg), and 119 (37.8%) weighed >175 lbs (79.5 kg), theoretically allowing collection of an additional 101.4 liters (16% more plasma) from both heavier categories based on FDA standards for plasma donor quantities. BMI was positively associated with age, mean arterial pressure (MAP), and pulse (Pearson's r = 0.36, 0.24, and 0.18, resp., P values <0.05), but not with oral temperature. Average BMI for females was higher than for males (+1.8, P = 0.01), and BMI for African Americans was higher than for White and Asian participants (+2.2 and +5.1, resp., Ps <0.05). A significant association was also found in the sex by race interaction with BMI (P = 0.0004). Follow-up analyses suggested a significant difference in BMI by sex among African Americans, higher BMI among African American females than Asian and White males, and higher BMI among White females than African American males (Ps <0.05).

Evidence for fetal programming of obesity with a focus on putative mechanisms

Obesity is associated with insulin resistance, the metabolic syndrome (a clustering of three or more of increased waist circumference, blood pressure, fasting glucose and fasting plasma triacylglycerol levels and reduced HDL levels), and a marked increase in the risk of type 2 diabetes and CHD. The impact of obesity differs between individuals, particularly between men and women and between ethnic groups. For example, in South Asians, although overall obesity is less prevalent, central obesity and the metabolic syndrome are more prevalent than in Europeans and this pattern is associated with the development of type 2 diabetes and CHD at an earlier age. It is important to examine individual risk factors contributing to obesity because they may have a different impact in population subgroups. Many factors contribute to the aetiology of obesity and there is increasing evidence to suggest that altered early development is one such factor and is associated with abnormal fat accumulation, the metabolic syndrome and type 2 diabetes in later life. The present review presents this evidence and discusses some of the mechanisms that may be involved in the pathogenesis of the programming of obesity.