Dietary patterns, abdominal visceral adipose tissue, and cardiometabolic risk factors in African Americans: the Jackson heart study

Microvascular vasoregulatory dysfunction in African Americans - An enhanced opportunity for early prevention and treatment of atherosclerotic cardiovascular disease

Atherosclerotic cardiovascular disease and its risk factors and precursors are a major driver of disparities in cardiovascular health. This review examines reported evidence that vascular endothelial dysfunction, and its manifestation as coronary microvascular dysfunction, underlies observed excess morbidity and mortality in African Americans. Advanced imaging insights that reveal patho-mechanisms, along with population evidence from the Jackson Heart Study, and the growing evidence emanating from national and international clinical trials and registries are presented. We examine a physiological framework that recognizes insulin-resistant cardiometabolic underpinnings of the conditions of the American Heart Associations' Life's Essential Eight construct of cardiovascular health as a unifying basis that affords early prevention. Mechanistic-based therapeutic approaches, can subsequently be implemented to interrupt progression to adverse outcomes employing layered, or personalized, treatment strategies of a well-defined set of conditions or diseases. Remaining knowledge gaps are acknowledged.

Adiposity, Physical Function, and Their Associations With Insulin Resistance, Inflammation, and Adipokines in CKD

RATIONALE & OBJECTIVES

Adiposity and physical fitness levels are major drivers of cardiometabolic risk, but these relationships have not been well-characterized in chronic kidney disease (CKD). We examined the associations of visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), intrahepatic fat, and physical function with inflammation, insulin resistance, and adipokine levels in patients with CKD.

STUDY DESIGN

Prospective cohort study.

SETTING & PARTICIPANTS

Participants with stages 3-5 CKD not receiving maintenance dialysis, followed up at one of 8 clinical sites in the Chronic Renal Insufficiency Cohort (CRIC) Study, and who underwent magnetic resonance imaging of the abdomen at an annual CRIC Study visit (n = 419).

PREDICTORS

VAT volume, SAT volume, intrahepatic fat, body mass index, waist circumference, and time taken to complete the 400-m walk test (physical function).

OUTCOMES

Markers of inflammation (interleukin 1β [IL-1β], IL-6, tumor necrosis factor receptor 1 [TNFR1], and TNFR2), insulin resistance (homeostasis model assessment of insulin resistance), and adipokine levels (adiponectin, total and high molecular weight, resistin, and leptin).

ANALYTICAL APPROACH

Multivariable linear regression of VAT and SAT volume, intrahepatic fat, and physical function with individual markers (log-transformed values), adjusting for relevant covariates.

RESULTS

Mean age of the study population was 64.3 years; 41% were women, and mean estimated glomerular filtration rate was 53.2±14.6 (SD) mL/min/1.73m². More than 85% were overweight or obese, and 40% had diabetes. Higher VAT volume, SAT volume, and liver proton density fat fraction were associated with lower levels of total and high-molecular-weight adiponectin, higher levels of leptin and insulin resistance, and lower high-density lipoprotein cholesterol and higher serum triglyceride levels. A slower 400-m walk time was associated only with higher levels of leptin, total adiponectin, plasma IL-6, and TNFR1 and did not modify the associations between fat measures and cardiometabolic risk factors.

LIMITATIONS

Lack of longitudinal data and dietary details.

CONCLUSIONS

Various measures of adiposity are associated with cardiometabolic risk factors. Physical function was also associated with the cardiometabolic risk factors studied and does not modify associations between fat measures and cardiometabolic risk factors. Longitudinal studies of the relationship between body fat and aerobic fitness with cardiovascular and kidney disease progression are warranted.

Association of smoking with abdominal adipose deposition and muscle composition in Coronary Artery Risk Development in Young Adults (CARDIA) participants at mid-life: A population-based cohort study

BACKGROUND

Smokers have lower risk of obesity, which some consider a "beneficial" side effect of smoking. However, some studies suggest that smoking is simultaneously associated with higher central adiposity and, more specifically, ectopic adipose deposition. Little is known about the association of smoking with intermuscular adipose tissue (IMAT), an ectopic adipose depot associated with cardiovascular disease (CVD) risk and a key determinant of muscle quality and function. We tested the hypothesis that smokers have higher abdominal IMAT and lower lean muscle quality than never smokers.

METHODS AND FINDINGS

We measured abdominal muscle total, lean, and adipose volumes (in cubic centimeters) and attenuation (in Hounsfield units [HU]) along with subcutaneous (SAT) and visceral adipose tissue (VAT) volumes using computed tomography (CT) in 3,020 middle-aged Coronary Artery Risk Development in Young Adults (CARDIA) participants (age 42-58, 56.3% women, 52.6% white race) at the year 25 (Y25) visit. The longitudinal CARDIA study was initiated in 1985 with the recruitment of young adult participants (aged 18-30 years) equally balanced by female and male sex and black and white race at 4 field centers located in Birmingham, AL, Chicago, IL, Minneapolis, MN, and Oakland, CA. Multivariable linear models included potential confounders such as physical activity and dietary habits along with traditional CVD risk factors. Current smokers had lower BMI than never smokers. Nevertheless, in the fully adjusted multivariable model with potential confounders, including BMI and CVD risk factors, adjusted mean (95% CI) IMAT volume was 2.66 (2.55-2.76) cm3 in current smokers (n = 524), 2.36 (2.29-2.43) cm3 in former smokers (n = 944), and 2.23 (2.18-2.29) cm3 in never smokers (n = 1,552) (p = 0.007 for comparison of former versus never smoker, and p < 0.001 for comparison of current smoker versus never and former smoker). Moreover, compared to participants who never smoked throughout life (41.6 [41.3-41.9] HU), current smokers (40.4 [39.9-40.9] HU) and former smokers (40.8 [40.5-41.2] HU) had lower lean muscle attenuation suggesting lower muscle quality in the fully adjusted model (p < 0.001 for comparison of never smokers with either of the other two strata). Among participants who had ever smoked, pack-years of smoking exposure were directly associated with IMAT volume (β [95% CI]: 0.017 [0.010-0.025]) (p < 0.001). Despite having less SAT, current smokers also had higher VAT/SAT ratio than never smokers. These findings must be viewed with caution as residual confounding and/or reverse causation may contribute to these associations.

CONCLUSIONS

We found that, compared to those who never smoked, current and former smokers had abdominal muscle composition that was higher in adipose tissue volume, a finding consistent with higher CVD risk and age-related physical deconditioning. These findings challenge the belief that smoking-associated weight loss or maintenance confers a health benefit.

Dietary Patterns and Metabolic Syndrome in Adult Subjects: A Systematic Review and Meta-Analysis

Metabolic Syndrome (MetS) constitutes a relevant public health burden. Several studies have demonstrated the association between diet and MetS. We performed a systematic review and meta-analysis to provide an estimate of the association between dietary patterns defined through a posteriori methods and MetS. A literature search on PubMed, Web of Science, and Scopus databases, up to March 2019, was conducted to identify all eligible case-control, prospective, or cross-sectional studies involving adult subjects of both sexes. Random-effects models were used. Heterogeneity and publication bias were evaluated. Stratified analyses were conducted on study characteristics. Forty observational studies were included in the meta-analysis, which identified the “Healthy” and the “Meat/Western” dietary patterns. The “Healthy” pattern was associated with reduced MetS risk (OR = 0.85; 95% confidence interval (CI): 0.79–0.91) and significantly decreased the risk in both sexes and in Eastern countries, particularly in Asia. Adherence to the “Meat/Western” pattern increased MetS risk (OR = 1.19; 95% CI: 1.09–1.29) and the association persisted in the stratified analysis by geographic area (Asia, Europe, America) and study design. Lifestyle is linked to risk of developing MetS. The “Healthy” and “Meat/Western” patterns are significantly associated with reduced and increased MetS risk, respectively. Nutrition represents an important modifiable factor affecting MetS risk.

Breastfeeding duration is associated with offspring’s adherence to prudent dietary pattern in adulthood: results from the Nutritionist’s Health Study

Little is known about the long-term effect of breastfeeding on dietary habits. We examined the association between breastfeeding duration and adherence to current dietary patterns of young women. This was a cross-sectional analysis of 587 healthy women aged ≤45 years, undergraduates or nutrition graduates. Maternal characteristics and breastfeeding duration [<6; 6–<12; ≥12 months (reference)] were recalled. Diet was assessed using a food frequency questionnaire and patterns were identified using factor analysis by principal component. Adherence to patterns was categorized in tertiles; the first (T1 = reference) was compared to T2 + T3 (moderate-to-high adherence). Logistic regression was performed considering the minimal sufficient adjustment recommended by the directed acyclic graph. Median age was 22 (interquartile range (IQR) 20; 27) years and body mass index (BMI) 22.2 (IQR 20.4; 25.0) kg/m2. The four dietary patterns identified (Processed, Prudent, Brazilian and Lacto-vegetarian) explained 27% of diet variance. Women breastfed for <6 months showed lower chance of moderate-to-high adherence to the Prudent pattern (odds ratio (OR) = 0.53, p = 0.04). Breastfeeding was not associated with the other patterns. Maternal pre-pregnancy BMI was directly associated with moderate-to-high adherence to the Processed pattern (OR = 2.01, p = 0.03) and inversely to the Prudent pattern (OR = 0.52, p = 0.02). Higher adherence to the Brazilian pattern was associated with proxies of low socioeconomic status and the Lacto-vegetarian pattern with the opposite. Confirmation in prospective studies of the association found in this study between breastfeeding with the Prudent pattern in adult offspring could suggest that early feeding practices influence long-term dietary habits, which could then affect the risk of nutrition-related diseases.

Waist-hip ratio as a predictor of myocardial infarction risk: A systematic review and meta-analysis

BACKGROUND AND AIM

Several studies have identified that obesity and being overweight can increase the risk of developing myocardial infarction (MI). However, the predictive value of the central obesity index, that is, the waist-hip ratio (WHR), regarding MI risk remains unclear. This study aimed to provide a systematic review and meta-analysis of WHR as a predictor of MI incidence.

METHODS

This study used relevant keywords and MeSH terms to identify studies of MI risk and WHR from PubMed, Web of Science, Embase, and Cochrane databases in November 2017.

RESULTS

We conducted a meta-analysis of 12 case-control studies in 14 eligible trials and further explored whether the predictive value of WHR on MI risk varies according to sex. The results showed that a high WHR increased MI risk (pooled odds ratio [OR] 2.62, 95% confidence interval [CI] 2.02-3.39, P < 0.00001) and that elevated WHR is more strongly predictive of MI in women than in men (pooled OR 4.63, 95% CI 3.28-6.53 in women; pooled OR 2.71, 95% CI 2.15-3.41 in men).

CONCLUSIONS

MI is significantly associated with increased WHR, with a stronger association among women.

Relation of uric acid level to rapid kidney function decline and development of kidney disease: The Jackson Heart Study

Whether elevated uric acid (UA) is an independent risk factor for chronic kidney disease (CKD) is not well established. The authors evaluated the relationship of UA with rapid kidney function decline (RKFD) and incident CKD among 3702 African Americans (AAs) in the Jackson Heart Study with serum UA levels measured at baseline exam (2000-2004). RKFD was defined as ≥ 30% eGFR loss and incident CKD as development of eGFR < 60 mL/min/1.73 m2 with a ≥ 25% decline in eGFR between baseline and exam 3 (2009-2013). RKFD and CKD were found in 11.4% and 7.5% of the participants, respectively. In a fully adjusted model, the odds of RKFD (OR, 1.8; 95% CI, 1.25-2.49) and incident CKD (OR, 2.00; 95% CI, 1.31-3.06) were significantly higher among participants in the top UA quartile vs bottom quartile. In the JHS, elevated UA was significantly associated with RKFD and incident CKD.

A posteriori dietary patterns and metabolic syndrome in adults: a systematic review and meta-analysis of observational studies

OBJECTIVE

Observational studies reported potential associations between different dietary patterns and the risk of metabolic syndrome (MetS); however, a consistent perspective has not been established to date. The current systematic review and meta-analysis aimed to evaluate the relationship between a posteriori dietary patterns and MetS by pooling available data.

DESIGN

MEDLINE and EMBASE databases were searched for relevant articles published up to July 2015 with no time restriction and with English language restriction. Two independent reviewers completed study selection and data extraction. Random-effects models (DerSimonian-Laird method) were used to pool effect sizes of eligible studies. The potential sources of heterogeneity were assessed using the I2 statistic.

RESULTS

Nineteen papers that identified dietary patterns using an a posteriori method were selected and included in the meta-analysis. The 'Healthy/Prudent' dietary pattern was inversely associated with risk of MetS (OR=0·89; 95 % CI 0·84, 0·94, P=0·002). In contrast, the 'Unhealthy/Western' dietary pattern had a significant positive association with risk of MetS (OR=1·16; 95 % CI 1·11, 1·22, P<0·001).

CONCLUSIONS

Our findings provide evidence that greater adherence to a healthy/prudent dietary pattern is associated with a lower risk of MetS, while an unhealthy/Western dietary pattern is associated with increased risk of MetS. These data suggest that a diet based on healthy food choices is also beneficial for prevention of MetS.

Longitudinal Analysis of Nut-Inclusive Diets and Body Mass Index Among Overweight and Obese African American Women Living in Rural Alabama and Mississippi, 2011-2013

Introduction

Nuts, when eaten alongside other nutritionally rich foods, may decrease obesity and related chronic disease risks, which are high among African American women in the rural South. We monitored changes in nut intake, other obesity-related foods (fruits, vegetables, red or processed meats, added sugars), and body mass index (BMI) over a 2-year weight loss intervention among 383 overweight and obese African American women in rural Alabama and Mississippi.

Methods

Two dietary recalls were administered at 4 points over 24 months. Mann–Whitney tests compared differences in median food group intake between nut consumers and non-nut consumers, and t tests identified BMI differences between groups. Mixed linear models tested the relationship between nut intake and intake of the select food groups, and between nut intake and BMI over time.

Results

Overall nut consumers ate more fruits and vegetables and less red meat than non-nut consumers. Nut consumers had lower BMI values than non-nut consumers. Weight loss by the end of the intervention was significant for nut consumers but not for non-nut consumers, even after accounting for kilocalorie consumption and physical activity engagement.

Conclusion

Nut consumption is associated with consumption of other nutritionally rich foods and lower BMI among African American women in rural Alabama and Mississippi. Future interventions should target increasing daily nut intake, decreasing added sugar intake, and identifying strategies to encourage positive dietary changes to continue after an intervention.

Effect of gender and adiposity on in vivo vascular function in young African Americans

The relationship between obesity and high blood pressure is not as strong among African Americans (AA) as compared to Caucasians. We designed the current study to determine the effect of adiposity on vascular endothelial function (a harbinger of hypertension) among young healthy AA without additional cardiovascular disease risk factors. A total of 108 AA subjects (46 women) between the ages of 18 and 45 years were recruited. All the subjects were normotensive, nonsmokers, and normoglycemic. Anthropometric and cardiovascular disease risk factor measurements (lipid, insulin resistance, and inflammatory markers) were obtained. Vascular endothelial function was measured by brachial artery flow-mediated dilation (FMD). Adiposity distribution was measured by using magnetic resonance imaging scan. There were no gender differences in age and levels of blood pressure, lipids, insulin resistance, and inflammatory markers. Women had higher total body fat percentage and higher peripheral adiposity compared to men. We observed that total and central adiposity did not correlate significantly with brachial artery FMD in women (r = -0.12 and r = 0.23, respectively; P = NS). However, in men, waist circumference was positively associated with FMD (r = 0.3, P ≤ .05). Hyperemic flow was negatively correlated significantly with total and central adiposity in men (r = -0.34 and r = -0.48, respectively; P < .05), but not in women (r = -0.26 and r = 0.03, respectively; P = NS). Our study suggests that increased adiposity may pose greater risk to AA men compared to AA women by adversely affecting resistance vessel function (as measured by hyperemic flow). Larger studies are necessary to validate these findings.

Dietary Patterns Among Overweight and Obese African-American Women Living in the Rural South

INTRODUCTION

Obesity and chronic diseases disproportionately affect African-American women in the rural South (US) and may be influenced by adherence to a typical Southern-style diet. There is a need to examine dietary patterns of this population and to determine if consumption of nutritionally rich foods like nuts is associated with consumption of other nutritious foods. The objectives of this study were to identify (1) dietary patterns of overweight/obese African-American women in the rural South; (2) the role that nuts play in the diet; (3) and adherence to federal food group recommendations across dietary patterns.

METHODS

Secondary data analysis of two baseline 24-h dietary recalls was performed on 383 overweight/obese African-American women enrolled in a weight loss intervention in Alabama and Mississippi between 2011 and 2013. Cluster analysis identified dietary patterns. t tests and chi-square tests tested demographic and dietary differences across clusters. The proportion of women in each cluster who met federal recommendations for fruit, vegetable, nuts, added sugar, and sodium intake was calculated.

RESULTS

Two dietary patterns were found. Nut intake frequency was higher in cluster 2 (P < .001), which was characterized by a higher intake frequency of fruits and vegetables, but high mean daily intake of added sugar (12.26 ± 7.67 tsp) and sodium (2800 ± 881 mg). Ninety-two percent of participants in this cluster consumed red/processed meats daily.

CONCLUSION

Even among women in this population who consume a more plant-based dietary pattern containing nuts, there is still a need to decrease intake of added sugar, sodium, and red meat.

Metabolic syndrome and dietary patterns: a systematic review and meta-analysis of observational studies

PURPOSE

Lifestyle is linked to the risk of developing metabolic syndrome (MetS); however, its relationship with dietary patterns remains unclear. This systematic review and meta-analysis aims to analyse the association of a posteriori dietary patterns with the metabolic syndrome.

METHODS

The PubMed, CINAHL and Scopus databases were searched for epidemiological studies of dietary patterns and MetS. The association between dietary patterns and MetS was estimated using a random-effects meta-analysis with 95 % confidence intervals (CIs).

RESULTS

A total of 28 cross-sectional studies and three cohort studies were included in the meta-analysis. In a comparison of the highest to the lowest category of prudent/healthy dietary patterns, the pooled odds ratio (OR) for MetS was 0.83 (95 % CI 0.76, 0.90; P for heterogeneity =0.0; and I ² = 72.1 %) in cross-sectional studies, and the pooled relative risk (RR) for MetS in cohort studies was 0.91 (95 % CI 0.68, 1.21; P for heterogeneity =0.005; I ² = 81.1 %). The pooled OR for MetS in a comparison of the highest to the lowest category of Western dietary patterns was 1.28 (95 % CI 1.17, 1.40; P for heterogeneity =0.0; and I ² = 72.0 %) in cross-sectional studies, and the RR was 0.96 (95 % CI 0.53, 1.73; P for heterogeneity =0.102; I ² = 62.6 %) in cohort studies.

CONCLUSIONS

The results from cross-sectional studies showed that a prudent/healthy pattern is associated with a lower prevalence of MetS, whereas a Western/unhealthy is associated with an increased risk for MetS. Additional prospective studies are needed to confirm the association between dietary patterns and MetS.

[Abdominal obesity and other cardiometabolic risk biomarkers: influence of socioeconomic status and lifestyle on two African-origin population groups, Cotonou (Benin) and Port-au-Prince (Haiti)]

INTRODUCTION

Increased cardio metabolic risk (CMR) in low- and middle-income countries is largely due to rapid nutrition transition. We conducted a study of two African-origin populations groups living, however, in widely different settings. It aimed to assess the relationship between lifestyle and CMR biomarkers as well as between abdominal obesity (AO) and other biomarkers.

METHODS

The study included 200 Benineses from Cotonou and 252 Haitians from Port-with-Prince (PAP) aged between 25 to 60 years and apparently in good health. AO was specifically defined as waist circumference ≥ 88cm (men) and ≥ 95 cm (women). Other most common biomarkers were: high total cholesterol/HDL cholesterol ratio, high blood pressure and insulin resistance by HOMA (Homeostasis Model Assessement). Socioeconomic status, diet, alcohol and tobacco were documented by questionnaire. Two dietary patterns emerged from cluster analysis, one traditional and the other "transitional" with increasing frequency of western foods.

RESULTS

Socioeconomic status, consumption of alcohol and nicotinism were associated with CMR, but not the food diagram. AO was associated with other CMR markers, with no marked effect of socioeconomic status and lifestyle variables.

CONCLUSION

Specific TT threshold values are confirmed as socioeconomic status and lifestyle have an impact on CMR, but not the relationship between AO and other CMR biomarkers.

Capacity-Building for Career Paths in Public Health and Biomedical Research for Undergraduate Minority Students: A Jackson Heart Study Success Model

OBJECTIVE

This article chronicles the building of individual student capacity as well as faculty and institutional capacity, within the context of a population-based, longitudinal study of African Americans and cardiovascular disease. The purpose of this article is to present preliminary data documenting the results of this approach.

DESIGN

The JHS Scholars program is designed, under the organizational structure of the Natural Sciences Division at Tougaloo College, to provide solid preparation in quantitative skills through: good preparation in mathematics and the sciences; a high level of reading comprehension; hands-on learning experiences; and mentoring and counseling to sustain the motivation of the students to pursue further studies.

SETTING

This program is on the campus of a private Historically Black College in Mississippi.

PARTICIPANTS

The participants in the program are undergraduate students.

MAIN OUTCOME MEASURES

Data, which included information on major area of study, institution attended, degrees earned and position in the workforce, were analyzed using STATA 14.

RESULTS

Of 167 scholars, 46 are currently enrolled, while 118 have graduated. One half have completed graduate or professional programs, including; medicine, public health, pharmacy, nursing, and biomedical science; approximately one-fourth (25.4 %) are enrolled in graduate or professional programs; and nearly one tenth (9.3%) completed graduate degrees in law, education, business or English.

CONCLUSIONS

These data could assist other institutions in understanding the career development process that helps underrepresented minority students in higher education to make career choices on a path toward public health, health professions, biomedical research, and related careers.

A visceral adiposity index-related dietary pattern and the cardiometabolic profiles in women with polycystic ovary syndrome

BACKGROUND & AIMS

Visceral adiposity index (VAI), an indicator of visceral adiposity, has been found to be associated with cardiometabolic disturbances in women with polycystic ovary syndrome (PCOS). The association of dietary intakes with VAI, and subsequently cardiometabolic variables is still unclear. The aims of this study were to identify a dietary pattern associated with VAI and to investigate whether this pattern is associated with cardiometabolic variables in PCOS women.

METHODS

The study was conducted on 53 PCOS women, aged 18-45 years, diagnosed according to National Institutes of Health (NIH) criteria, and 167 age-matched normo-ovulatory women who were recruited from the Tehran Lipid and Glucose Study. Reduced rank regression was applied to determine a dietary pattern that explains the maximum variation of the VAI. Associations between the dietary pattern and cardiometabolic profiles were investigated using linear and logistic regression, adjusted for age and BMI.

RESULTS

A VAI dietary pattern was identified characterized by high consumption of fried vegetables, vegetable oils (except olive oil), salty snacks, legumes, eggs, fast foods and low consumption of traditional sweets, high and low fat dairy, cruciferous vegetables, sugars and honey. A one standard deviation (SD) increase in dietary pattern score was significantly associated with higher triglycerides (TGs) (βcontrol = 0.22, p = 0.003; βcase = 0.48, p = 0.001) and TGs/HDL-C ratio (βcontrol = 0.23, p = 0.002; βcase = 0.52, p = 0.001) in both groups. After adjusting for age and BMI, a 1-SD increase in dietary pattern score was associated with increased risk of VAD in PCOS (OR 2.77; 95% CI 1.15, 6.66) and control groups (OR 2.41; 95% CI 1.41-4.12). In the control group, the risk of hypercholesterolemia, hypertriglyceridemia, high LDL-C, low HDL-C, hyperglycemia and IGT + IFG increased significantly per 1-SD increase in dietary pattern score, which all remained significant after adjusting for age and BMI, except for the risk of high LDL-C. Among the cardiometabolic abnormalities, only the risk of hypertriglyceridemia was significantly associated with dietary pattern score in women with PCOS, which lost its significance after adjusting for age and BMI.

CONCLUSION

The VAI dietary pattern affects most cardiometabolic variables in controls, but to a lesser extent in PCOS women. Our study suggests that relationships between diet and cardiometabolic risk profiles may be modified by PCOS status.

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.

Dietary Patterns of Young Females and Their Association With Waist Circumference as a Health Index in Northwest of Iran, 2007

Background:

Despite the higher prevalence of overweight and obesity among young people in western countries, the 50th and 95th percentile ranks for waist circumference in the Iranian young Females are higher than those of the western ones.

Objectives:

Identifying major dietary patterns in Iranian young females, which associate with central obesity, can probably explain the difference between Iranian young females’ pattern and those of their western peers regarding obesity.

Patients and Methods:

In the current cross-sectional study, a total of 257 young females aged 11 - 15 years old from Talaat Intelligent Guidance School, Tabriz, Iran (2007) were selected for the study using non-probability simple sampling method. Then, usual dietary intakes of all subjects were evaluated by a food frequency questionnaire and anthropometric measurements such as weight, height, waist circumference, and Body Mass Index (BMI) using the standard protocols. Data were analyzed by inferential statistics (One-way ANOVA, Tukey test for Post-Hoc Analysis, Chi-square test, age-adjusted means, analysis of covariance with Bonferroni correction, correlation and partial correlation) by SPSS software.

Results:

In the current study, six major dietary patterns were extracted using factor analysis method. Before and after controlling the age, subjects in the upper tertile of the Iranian Central Obesity Making Dietary Pattern (rich in cruciferous vegetables, green leafy vegetables, soft drinks, tomatoes, other vegetables and vegetable oils) had larger waist circumference in comparison with the ones in the lower tertile (before controlling for age: 64.2 ± 9 vs. 61.6 ± 7 P = 0.03; after: 64.5 ± 0.8 vs. 61.5 ± 0.8, P = 0.009). However in lacto vegetarian dietary pattern (rich in legumes, potato, other vegetables, dough, high-fat dairy products and margarine), individuals in the upper tertile had significantly lower weight, waist circumference and body mass index (BMI) in comparison with the ones in the lower tertile (weight: 44.9 ± 9.3 vs. 51.4 ± 10.6, P < 0.01; WC: 59.9 ± 8 vs. 64 ± 7.9, P < 0.01; BMI: 18.6 ± 3.1 vs. 20.6 ± 3.5, P < 0.01).

Conclusions:

The current study findings suggest that the Iranian Central Obesity Making Dietary Pattern is directly associated with waist circumference (marker of central obesity), while lacto vegetarian dietary pattern is reversely associated with weight, waist circumference and BMI. Special obesity pattern in Iranian young females can be justified by Iranian Central Obesity Making Dietary Pattern”.

Elevated serum advanced glycation endproducts in obese indicate risk for the metabolic syndrome: a link between healthy and unhealthy obesity?

CONTEXT

Although obesity can predispose to the metabolic syndrome (MS), diabetes, and cardiovascular disease, not all obese subjects develop MS, hence the need for new indicators of risk for this syndrome. Advanced glycation end products (AGEs) correlate with factors involved in the MS, including inflammation and insulin resistance (IR). Because AGEs can be derived from food and are modifiable, it is important to determine whether they are a risk factor for MS.

OBJECTIVE

The objective of this study was to assess the association of endogenous and exogenous AGEs with MS criteria.

DESIGN

The following data were collected in a cross-sectional study of subjects with and without the MS: serum AGEs (sAGEs) and mononuclear cell AGEs, metabolites, pro- and antiinflammatory markers, body fat mass measures, including abdominal magnetic resonance imaging, and caloric and dietary AGE (dAGE) consumption.

SETTING

The study was conducted in the general community.

PARTICIPANTS

Participants included 130 MS and 139 non-MS subjects of both sexes, older than 50 years.

RESULTS

sAGEs ((ϵ)N-carboxymethyllysine, methylglyoxal) were markedly elevated in obese persons with more than one other MS criteria but not in obese without MS criteria. sAGEs directly correlated with markers of IR (HOMA) and inflammation (leptin, TNFα, RAGE) and inversely with innate defenses (SIRT1, AGE receptor 1 [AGER1], glyoxalase-I, adiponectin). sAGEs correlated with dAGEs but not with calories, nutrient consumption, or fat mass measures. Consumption of dAGE, but not of calories, was markedly higher in MS than in non-MS.

CONCLUSION

High sAGEs, a modifiable risk factor for IR, may indicate risk for the MS, type 2 diabetes, and cardiovascular disease. High dietary AGE consumption and serum AGE levels may link healthy obesity to at-risk obesity.

Racial/ethnic disparities in prevalence and care of patients with type 2 diabetes mellitus

BACKGROUND

As of 2012, nearly 10% of Americans had diabetes mellitus. People with diabetes are at approximately double the risk of premature death compared with those in the same age groups without the condition. While the prevalence of diabetes has risen across all racial/ethnic groups over the past 30 years, rates are higher in minority populations. The objective of this review article is to evaluate the prevalence of diabetes and disease-related comorbidities as well as the primary endpoints of clinical studies assessing glucose-lowering treatments in African Americans, Hispanics, and Asians.

METHODS

As part of our examination of this topic, we reviewed epidemiologic and outcome publications. Additionally, we performed a comprehensive literature search of clinical trials that evaluated glucose-lowering drugs in racial minority populations. For race/ethnicity, we used the terms African American, African, Hispanic, and Asian. We searched PubMed for clinical trial results from 1996 to 2015 using these terms by drug class and specific drug. Search results were filtered qualitatively.

RESULTS

Overall, the majority of publications that fit our search criteria pertained to native Asian patient populations (i.e., Asian patients in Asian countries). Sulfonylureas; the α-glucosidase inhibitor, miglitol; the biguanide, metformin; and the thiazolidinedione, rosiglitazone have been evaluated in African American and Hispanic populations, as well as in Asians. The literature on other glucose-lowering drugs in non-white races/ethnicities is more limited.

CONCLUSIONS

Clinical data are needed for guiding diabetes treatment among racial minority populations. A multi-faceted approach, including vigilant screening in at-risk populations, aggressive treatment, and culturally sensitive patient education, could help reduce the burden of diabetes on minority populations. To ensure optimal outcomes, educational programs that integrate culturally relevant approaches should highlight the importance of risk-factor control in minority patients.

MRI-determined total volumes of visceral and subcutaneous abdominal and trunk adipose tissue are differentially and sex-dependently associated with patterns of estimated usual nutrient intake in a northern German population

BACKGROUND

Visceral (VAT) and subcutaneous abdominal (SAAT) and trunk (STRAT) adipose tissue (AT) have been suggested to be differentially influenced by diet.

OBJECTIVE

We investigated whether and to what extent usual patterns of nutrient intake are associated with VAT, SAAT, and STRAT compared with nondietary predictors in northern German adults (n = 583).

DESIGN

AT volumes were quantified by magnetic resonance imaging. Nutrient intake was estimated by a 112-item food-frequency questionnaire linked to the German Food Code and Nutrient Database. Exploratory nutrient patterns were derived by principal components analysis (PCA) and partial least-squares regression (PLS) of 87 nutrients. Cross-sectional associations between nutrient patterns, single nutrients, or total energy intake and AT compartments were analyzed by multiple linear regression.

RESULTS

Next to sex and age, respectively, which were important nondietary predictors and accounted for more of the variation in VAT (∼13% and ∼4%) than in SAAT or STRAT (both 4-7% and <1%), variation in VAT (16.8% or 17.6%) was explained to a greater extent by 9 or 2 nutrient patterns derived by principal components analysis or partial least-squares regression, respectively, than was variation in SAAT (10.6% or 8.2%) or STRAT (11.5% or 8.6%). Whereas VAT (16.6%) was primarily explained by nutrient quality, SAAT (6.9%) and STRAT (7.4%) were mainly explained by total energy intake. VAT was positively associated with nutrients characteristic of animal (except for dairy) products, including arachidonic acid (standardized β: 0.25; 95% CI: 0.15, 0.34; P < 0.0001), but negatively with dietary fiber, including polypentoses (standardized β: -0.17; 95% CI: -0.24, -0.09; P < 0.0001), and nutrients found in milk. The direction and strength of many associations, however, depended strongly on sex and adjustment for BMI.

CONCLUSION

VAT may be particularly associated with sex-specific interplays of nutrients found in animal products and fiber, whereas SAAT and STRAT are associated with total energy intake.

Dietary factors and higher blood pressure in African-Americans

Adverse blood pressure (BP) is a major independent risk factor for epidemic cardiovascular diseases affecting almost one third of the US adult population. This review synthesizes results from studies published over the past few years on BP differences and prevalent hypertension between US blacks and whites and their different intakes of foods (e.g., fruits, vegetables, and dairy products) and micronutrients (e.g., vitamin D, calcium, potassium, and phosphorus). Studies have consistently reported higher prevalence of adverse BP levels and hypertension and less favorable dietary intakes in blacks than in whites, but the influence of specific dietary factors on high BP risk for blacks remains unclear.

Associations of neighborhood area level deprivation with the metabolic syndrome and inflammation among middle- and older- age adults

Background

The study examines the association of neighborhood socioeconomic deprivation and metabolic syndrome with inflammation.

Methods

The analysis included 19, 079 black and white participants from the REasons for Geographic And Racial Differences in Stroke Study who were age > 45 years at baseline. Logistic regression examined whether neighborhood deprivation was associated with increased odds of METS and CRP-MetS.

Results

Among black adults, residing in the most deprived neighborhoods was associated with increased odds of obesity (p < .01), lower HDL (p < .001), high blood pressure (p < .01), elevated fasting glucose (p < .001), inflammation (p < .01), and CRP-MetS (p < .001). Among white adults, neighborhood deprivation was associated with higher waist circumference (p < .001), lower HDL (p < .001), higher triglycerides (p < .01), higher glucose (p < .001), higher BMI (p < .0001), higher blood pressure (p = .01), METS (p < .001), inflammation (p < .01) and CRP-MetS (p < .001).

Conclusions

These findings highlight the role of neighborhood socioeconomic deprivation on METS and CRP-MetS for black and white adults. Interventions tailored to address the contextual effects of deprived neighborhoods may reduce the observed neighborhood disparities.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2458-14-1319) contains supplementary material, which is available to authorized users.

Neighborhood safety and adipose tissue distribution in African Americans: the Jackson Heart Study

Objective

Patterns of fat distribution are heavily influenced by psychological stress, sex, and among women, by menopause status. Emerging evidence suggests the lack of perceived neighborhood safety due to crime may contribute to psychological stress and obesity among exposed residents. Our objective is to determine if perceived neighborhood safety is associated with abdominal adiposity among African-American men and women, and among pre- and postmenopausal women in the Jackson Heart Study.

Design and Methods

We examined associations between perceived neighborhood safety, fat distribution, and other individual-level covariates among Jackson Heart Study participants (N = 2,881). Abdominal adiposity was measured via computed tomography scans measuring the volumes of visceral, subcutaneous and total adipose tissue. We also measured body mass index (BMI), and waist circumference. Multivariable regression models estimated associations between perceived neighborhood safety, adiposity, and covariates by sex and menopause status.

Results

Adjusting for all covariates, women who strongly disagreed their neighborhood was safe from crime had a higher BMI compared to women who felt safe [Std B 0.083 95% CI (0.010, 0.156)]. Premenopausal women who felt most unsafe had higher BMI, waist circumference, and volumes of visceral and total adipose tissue than those who felt safe [Std B 0.160 (0.021, 0.299), Std B 0.142 (0.003, 0.280), Std B 0.150 (0.014, 0.285), Std B 0.154 (0.019, 0.290), respectively]. We did not identify associations between neighborhood safety and adiposity among men and postmenopausal women.

Conclusions

Our data suggest that abdominal adipose tissue distribution patterns are associated with perceived neighborhood safety in some groups, and that patterns may differ by sex and menopause status, with most associations observed among pre-menopausal women. Further research is needed to elucidate whether there are causal mechanisms underlying sex and menopause-status differences that may mediate associations between perceived safety and abdominal adiposity and potential protective factors that may modify this risk.

Metabolic actions of natriuretic peptides and therapeutic potential in the metabolic syndrome

Natriuretic peptides (NPs) are a group of peptide-hormones mainly secreted from the heart, signaling via c-GMP coupled receptors. NP are well known for their renal and cardiovascular actions, reducing arterial blood pressure as well as sodium reabsorption. Novel physiological functions have been discovered in recent years, including activation of lipolysis, lipid oxidation, and mitochondrial respiration. Together, these responses promote white adipose tissue browning, increase muscular oxidative capacity, particularly during physical exercise, and protect against diet-induced obesity and insulin resistance. Exaggerated NP release is a common finding in congestive heart failure. In contrast, NP deficiency is observed in obesity and in type-2 diabetes, pointing to an involvement of NP in the pathophysiology of metabolic disease. Based upon these findings, the NP system holds the potential to be amenable to therapeutical intervention against pandemic diseases such as obesity, insulin resistance, and arterial hypertension. Various therapeutic approaches are currently under development. This paper reviews the current knowledge on the metabolic effects of the NP system and discusses potential therapeutic applications.

Prevalence and associated factors of obesity among Panamanian adults. 1982-2010

BACKGROUND

In Central America, there has been a marked increase in obesity in the last 30 years. Over this time frame, in Panama, there have been lifestyle changes associated with economic development and urbanization that may have facilitated increases in body weight. The aim of the study is to describe the change in the prevalence of obesity in the country since 1982 and to analyze the association of obesity with gender, place of residence and socioeconomic factors.

METHODS

We analyzed three nationally representative cross-sectional studies and one sub-national study of Panamanian adults that evaluated anthropometric and socioeconomic variables; ENPA-1982 (n = 11 611), ENV-II 2003 (n = 14 737), ENV-III 2008 (n = 15 484), PREFREC-2010 (n  = 3 590). We also evaluated one nationally representative study that evaluated people's perception of their body weight, ENSCAVI-2007 (n = 25 748).

RESULTS

In 1982, the prevalence in males of a body mass index (BMI) ≥ 30 kg/m2 was 3.8% (3.3-4.2) and in females 7.6% (6.9-8.2). In 2003, the prevalence in males increased to 14.4% (13.6-15.2) and in females to 21.8% (20.8-22.7). In 2008, the prevalence in males was 16.9% (16.0-17.7) and in females it was 23.8% (22.8-24.7). Nevertheless, in 2007, the national perception of being obese was only 4% among males and 6.7% among females. The highest prevalence of obesity was noted in urban areas. Female gender and higher income were found to be positively associated with obesity. Income level was positively associated with abdominal obesity in men but not in women.

CONCLUSIONS

There has been a marked increase of obesity in Panama in the last 3 decades. Initiatives to control this problem will have to take into consideration the observed gender difference and the lifestyle changes that have contributed to the rise of this problem.

Race and ethnicity in cancer therapy: what have we learned?

Racial and ethnic disparities in the pathogenesis of common malignancies and outcomes from treatment remain a major health concern. Factors attributed to these disparities include differences in lifestyle, environment, genetics, and tumor biology. As we strive to personalize cancer therapy, it will be imperative that we understand the relative contributions of each factor so that we may apply this knowledge in choosing the best treatment for each individual, regardless of his or her racial or ethnic heritage.

Adherence to the 2006 American Heart Association Diet and Lifestyle Recommendations for cardiovascular disease risk reduction is associated with bone health in older Puerto Ricans

BACKGROUND

Cardiovascular disease (CVD) and osteoporosis are 2 major public health problems that share common pathophysiological mechanisms. It is possible that strategies to reduce CVD risk may also benefit bone health.

OBJECTIVE

We tested the hypothesis that adherence to the 2006 American Heart Association Diet and Lifestyle Recommendations (AHA-DLR) is associated with bone health.

DESIGN

We previously developed a unique diet and lifestyle score (American Heart Association Diet and Lifestyle Score; AHA-DLS) to assess adherence to the AHA-DLR. In a cross-sectional study of 933 Puerto Ricans aged 47-79 y, we modified the AHA-DLS to test associations with bone health. Bone mineral density (BMD) at the femoral neck, trochanter, total hip, and lumbar spine (L2-L4) was measured by using dual-energy X-ray absorptiometry.

RESULTS

For every 5-unit increase in the modified AHA-DLS, BMD at the femoral neck, trochanter, total hip, and lumbar spine (L2-L4) was associated with a 0.005-0.008-g/cm(2) (P < 0.05) higher value. No component of the AHA-DLR alone was responsible for the observed positive associations. For every 5-unit increase in the modified AHA-DLS, the odds for osteoporosis or osteopenia at the trochanter, total hip, and lumbar spine (L2-L4) were lower by 14% (OR: 0.86; 95% CI: 0.79, 0.92), 17% (OR: 0.83; 95% CI: 0.76, 0.92), and 9% (OR: 0.91; 95% CI: 0.84, 0.99), respectively.

CONCLUSIONS

Dietary guidelines for CVD risk reduction may also benefit bone health in this Hispanic cohort. Synchronizing dietary guidelines for these 2 common diseases may provide a simplified public health message. This trial was registered at clinicaltrials.gov as NCT01231958.

Genetic and molecular differences in prostate carcinogenesis between African American and Caucasian American men

Prostate cancer is the most common non-skin cancer and the second leading cause of cancer-related death for men in the United States. Prostate cancer incidence and associated mortality are highest in African American men in comparison to other races. The observed differences in incidence and disease aggressiveness at presentation support a potential role for different pathways of prostate carcinogenesis between African American and Caucasian men. This review focuses on some of the recent molecular biology discoveries, which have been investigated in prostate carcinogenesis and their likely contribution to the known discrepancies across race and ethnicity. Key discussion points include the androgen receptor gene structure and function, genome-wide association studies and epigenetics. The new observations of the ethnic differences of the ERG oncogene, the most common prostate cancer gene, are providing new insights into ERG based stratification of prostate cancers in the context of ethnically diverse patient populations. This rapidly advancing knowledge has the likely potential to benefit clinical practice. Current and future work will improve the ability to sub-type prostate cancers by molecular alterations and lead to targeted therapy against this common malignancy.