Abdominal obesity and the spectrum of global cardiometabolic risks in US adults

Association of comorbid depression and obesity with cardiometabolic multimorbidity among middle-aged and older Chinese adults: A cohort study

PURPOSE

To evaluate the association of comorbid depression and obesity with the risk of incident cardiometabolic multimorbidity among middle-aged and older Chinese adults.

METHODS

This cohort study extracted data from the 2011 and 2015 waves of the China Health and Retirement Longitudinal Study (CHARLS). Depression was confirmed by the 10-item Center for Epidemiologic Studies Depression Scale (CESD-10) with a cut-off score ≥10. Obesity was defined as a body mass index ≥28 kg/m². Participants were categorized into four groups based on depression and obesity status at baseline, i.e., with neither condition, depression only, obesity only, and with both conditions. Cardiometabolic multimorbidity was defined as the coexistence of two or more of heart diseases, stroke, and diabetes mellitus. Logistic regression models were established to estimate the associations.

RESULTS

A total of 9,308 participants without cardiometabolic multimorbidity at baseline were included (mean [SD] age, 58.8 [9.0] years; 4,449 [47.8%] were males). During four-year of follow-up, 349 (3.8%) participants developed cardiometabolic multimorbidity. Compared to participants without depression or obesity, comorbid depression and obesity was associated with greater risk of cardiometabolic multimorbidity (adjusted OR: 4.79, 95% CI: 3.09-7.43) than that in participants with depression alone (adjusted OR: 1.84, 95% CI: 1.37-2.46) or obesity alone (adjusted OR: 2.26, 95% CI: 1.48-3.45). The findings were consistent in different gender and age groups.

CONCLUSIONS

Comorbid depression and obesity was associated with excessive risk of cardiometabolic multimorbidity. Intervention targeting at individuals with both depression and obesity might have substantial benefit in minimizing the risk of cardiometabolic multimorbidity.

Role of central obesity on pain onset and its association with cardiovascular disease: a retrospective study of a hospital cohort of patients with osteoarthritis

OBJECTIVES

To determine the role of central obesity (CO) in the onset and severity of joint pain and in predicting cardiovascular disease (CVD) in subjects affected with osteoarthritis (OA).

DESIGN

Retrospective analysis on the onset of OA joint pain and CO. Waist circumference (WC), Waist-to-height ratio andwaist-to-hip ratio (WHR) were measured at the interview and defined according to the WHO criteria. Cross-sectional analyses on the association of comorbidities, including CVD, pain severity (number of joints and pain score) and CO.

SETTINGS AND PARTICIPANTS

Medical records and interviews of a hospital cohort study of 609 patients with OA. Analyses included analysis of variance, mean differences (MDs), SE and logistic regression. Areas under the receiver operating characteristic curve (AUROC) compared the predictive value of the sex-specific CVD models.

OUTCOME MEASURES

Onset of OA joint pain (years) and severity according to body mass index (BMI) and WC categories. Predictive value of WC for CVD by sex. Education level, disability, smoking and alcohol use were used to adjust the analysis.

RESULTS

Subjects with OA and CO by WHR started 2 years earlier with pain symptoms and had more joints affected than those without CO (MD=1.96 years, SE=0.95, p=0.04 and MD=0.32, SE=0.15 and p=0.04, respectively). Age and hypertension were associated with CVD in both genders, and NSAIDs use only in males. In addition, respiratory disease, hypercholesterolaemia, stairs difficulty, a wider WC and obesity were significant risk factors in females, improving 12.7% in the prediction of CVD cases, compared with only age and BMI (AUROCC=0.793 and 0.666, respectively, p=0.03 for the difference between AUROCs).

CONCLUSION

CO is associated with the onset of joint pain, and all pain analysed variables. CO has a role in CVD in women affected with OA and might help predict CVD cases.

Sex influences the effect of adiposity on arterial stiffness and renin‐angiotensin aldosterone system activity in young adults

Introduction

Methods

Results

Conclusion

Daily sitting time and its association with non-communicable diseases and multimorbidity in Catalonia

Background

Non-communicable diseases (NCDs) account for 71% of deaths worldwide and individual behaviours such as sedentariness play an important role on their development and management. However, the detrimental effect of daily sitting on multiple NCDs has rarely been studied. This study sought (i) to investigate the association between sitting time and main NCDs and multimorbidity in the population of Catalonia and (ii) to explore the effect of physical activity as a modifier of the associations between sitting time and health outcomes.

Methods

Cross-sectional data from the 2016 National Health Survey of Catalonia were analyzed, and multivariable logistic regression, adjusting for socio-demographics and individual risk factors (tobacco and alcohol consumption, diet, hyperlipidaemia, hypertension, body mass index) was used to estimated odds ratios (ORs) and 95% confidence intervals (CIs) of the association between sitting time and NCDs.

Results

A total of 3320 people ≥15 years old were included in the study. Sitting more than 5 h/day was associated with a higher risk of cardiovascular disease (OR 1.90, 95% CI: 1.21–2.97), respiratory disease (OR 1.61, 95% CI: 1.13–2.30) and multimorbidity (OR 2.80, 95% CI: 1.53–5.15). Sitting more than 3 h/day was also associated with a higher risk of multimorbidity (OR 2.26, 95% CI: 1.23–4.16). Physical activity did not modify the associations between sitting time and any of the outcomes.

Conclusions

Daily sitting time might be an independent risk factor for some NCDs, such as cardiovascular disease, respiratory disease and multimorbidity, independently of the level risk of physical inactivity.

Association Between Obesity and Blood Pressure in Common Korean People

Purpose

The aim of this study was to investigate the associations of high blood pressure (BP) and wide pulse pressure (PP) with obesity among common Korean people.

Materials and Methods

This study analyzed data from the Seventh Korean National Health and Nutrition Examination Survey (2017). The associations of BP with body mass index (BMI) and waist-to-height ratio (WHT2R) were investigated using their lump mean values.

Results

The BPs of males and females increased with BMI, the PP of females increased with BMI and then decreased, and the PP of males is nearly independent of BMI. The BPs of males and females increased to their maximum values with WHT2R and then decreased. The PPs of males and females increased with WHT2R.

Conclusion

BMI can be used as a useful predictor for high BP, and WHT2R can be used as a useful predictor for wide PP.

Whole-Body Cryotherapy Is an Effective Method of Reducing Abdominal Obesity in Menopausal Women with Metabolic Syndrome

Abdominal obesity predominates in menopausal women (MW) and contributes to the development of metabolic syndrome (MetS). It is associated with increased mortality related to cardiovascular disease, diabetes and fatty liver disease. The effects of whole-body cryotherapy (WBC) on body composition and the blood concentration of irisin, interleukin-6 (IL-6) and C-reactive proteins (CRP) in MW with MetS and in healthy women (HW), were assessed. The study included 19 women with MetS (61.53 ± 3.99 y, BMI 30.09 ± 4.98 kg/m²) and 18 HW (60.28 ± 3.63 y, BMI 25.50 ± 2.37 kg/m²) who were subjected to 20 WBC treatments at −130 °C for 3 min daily. In both groups, body mass (BM), BMI, abdominal circumference, triceps skinfold, total fat mass and percentage of leg fat significantly decreased after 20 WBC sessions. Additionally, the percentage of total, trunk and android fat in the MetS group were significantly decreased after 20 WBC applications. Waist circumference (WC) and waist-to-height ratio (WHtR) significantly decreased in both groups, and in the HW group, hip circumference and abdominal skinfold also significantly decreased after 10 WBC and 20 WBC treatments. In both groups, the concentration of plasma irisin significantly increased after 1 WBC and 10 WBC exposures, while the concentration of IL-6 significantly increased only in MetS group after 10 WBC and 20 WBC, and were significantly higher than in HW. CRP concentrations were significantly higher in the MetS group than in HW before 1 WBC, after 1 WBC and 10 WBC sessions, but not after 20. In the MetS group, there were significant negative correlations between the change in irisin level and the changes in WC and BM, and between the level of irisin and the change in percentage of total fat, and significant negative correlations between the change in IL-6 level and changes in WC, waist-to-hip ratio and WHtR. Whole-body cryotherapy, assuming the application of 20 treatments in the series, reduces abdominal obesity in menopausal women indirectly through the secretion of irisin and IL-6, and can be used as adjunctive therapy in the treatment of metabolic syndrome. Our conclusion is limited to menopausal women with low–moderate physical activity for whom its level as well as diet were not changed during the treatment.

R-α-Lipoic Acid and 4-Phenylbutyric Acid Have Distinct Hypolipidemic Mechanisms in Hepatic Cells

The constitutive activation of the mechanistic target of rapamycin complex 1 (mTORC1) leads to the overproduction of apoB-containing triacylglycerol-rich lipoproteins in HepG2 cells. R-α-lipoic acid (LA) and 4-phenylbutyric acid (PBA) have hypolipidemic function but their mechanisms of action are not well understood. Here, we reported that LA and PBA regulate hepatocellular lipid metabolism via distinct mechanisms. The use of SQ22536, an inhibitor of adenylyl cyclase, revealed cAMP’s involvement in the upregulation of CPT1A expression by LA but not by PBA. LA decreased the secretion of proprotein convertase subtilisin/kexin type 9 (PCSK9) in the culture media of hepatic cells and increased the abundance of LDL receptor (LDLR) in cellular extracts in part through transcriptional upregulation. Although PBA induced LDLR gene expression, it did not translate into more LDLR proteins. PBA regulated cellular lipid homeostasis through the induction of CPT1A and INSIG2 expression via an epigenetic mechanism involving the acetylation of histone H3, histone H4, and CBP-p300 at the CPT1A and INSIG2 promoters.

Association between Abdominal Obesity and Cardiovascular Risk Factors in Adults with Normal Body Mass Index: Based on the Sixth Korea National Health and Nutrition Examination Survey

Background

Abdominal obesity predisposes individuals to cardiovascular disease, but the data in adults with normal body mass index (BMI) are relatively rare. This study aimed to evaluate the characteristics of subjects with normal BMI and abdominal obesity and to identify the relationship between central obesity and cardiovascular risk factors in normal BMI adults in Korea.

Methods

Ten thousands six hundred thirty-four adults with BMI between 18.5 to 24.9 kg/m² who participated in the sixth Korea National Health and Nutrition Examination Survey were included. Abdominal obesity was defined as a waist circumference of ≥90 cm in males and ≥85 cm in females. Through logistic regression, we analyzed the factors influencing abdominal obesity and the relationship between abdominal obesity and cardiovascular risk factors.

Results

The prevalence of abdominal obesity in adults with normal BMI was 6.9% for males and 7.7% for females, and this prevalence tended to increase with age. When adjusted for age and BMI, daily excessive alcohol consumption increased the risk of abdominal obesity in adults of normal weight. Women with lower socioeconomic status and men in need of walking exercise also had a higher risk of abdominal obesity. In the model adjusted for age and BMI, abdominal obesity was associated with fasting glucose intolerance and diabetes in men and hypertriglyceridemia and low high-density lipoprotein cholesterol in women.

Conclusion

Cardiovascular risk factors were associated with abdominal obesity in Korean adults with normal BMI. These results suggest that more careful management of abdominal obesity in those with normal weight is necessary.

Physical Activity Level Is Associated With Maintaining Anthropometric Improvements Among Participants in a Worksite Wellness Program

Background. Physical activity (PA) can facilitate weight loss, help avoid weight regain, and improve body composition. This study examined the relationships between PA level and changes in anthropometric measures among university employees in a worksite wellness program. Methods. A registered dietitian provided individualized assessments at baseline followed by a 12-week education intervention with follow-up at 12 and 26 weeks. The International Physical Activity Questionnaire-Short Form was used to calculate PA ≤150 or ≥150 min/wk, median min/wk, and metabolic equivalent of task (MET) min/wk at each time point. Repeated-measures general linear model and nonparametric tests were used to assess significant differences over time. Results. Of the 64 participants, 89% were women and 50% were non-Hispanic white. At 12 and 26 weeks, participants experienced significant decreases in weight (P = .001). Among women, waist circumference and abdominal obesity decreased significantly (P < .01). PA ≥150 min/wk (n = 21) was associated with continued weight loss (P = .03) and decreases in body fat percentage (P = .02) between 12 and 26 weeks whereas PA ≤150 min/wk was associated with weight and body fat percentage regain during the same time period. Conclusion. Among women in a worksite wellness program, higher levels of PA were associated with avoiding weight and body fat regain following successful loss.

Changes in Sugar-Sweetened Soda Consumption, Weight, and Waist Circumference: 2-Year Cohort of Mexican Women

OBJECTIVES

To evaluate 2-year changes in soda consumption, weight, and waist circumference.

METHODS

We followed 11 218 women from the Mexican Teachers' Cohort from 2006 to 2008. Dietary data were collected using a semiquantitative food frequency questionnaire. Weight was self-reported, and waist circumference was self-measured. We used linear regression to evaluate changes in sugar-sweetened and sugar-free soda consumption in relation to changes in weight and waist circumference, adjusting for lifestyle and other dietary factors.

RESULTS

Compared with no change, a decrease in sugar-sweetened soda consumption by more than 1 serving per week was associated with less weight gain (-0.4 kg; 95% confidence interval [CI] = -0.6, -0.2). Conversely, relative to no change, an increase in sugar-sweetened soda by more than 1 serving per week was associated with a 0.3-kilogram (95% CI = 0.2, 0.5) increase in weight. An increase of 1 serving per day of sugar-sweetened soda was associated with a 1.0 kg (95% CI = 0.7, 1.2; P < .001) increase in weight. The results for waist circumference were similar.

CONCLUSIONS

Moderate changes in consumption of sugar-sweetened soda over a 2-year period were associated with corresponding changes in weight and waist circumference among Mexican women.

The six obesity indices, which one is more compatible with metabolic syndrome? A population based study

OBJECTIVES

The present study was conducted to determine the best discriminators in the diagnosis of the metabolic syndrome (MetS) among six obesity indexes. Furthermore the optimal cutoff points for all obesity indexes were determined.

METHODS

The baseline data of 5910 subjects of Haraz cohort study which was conducted in northern Iran were analyzed. Receiver operating characteristic (ROC) analyses were separately performed to determine discriminatory power of six obesity indexes, including, body mass index (BMI), waist circumference (WC), waist to hip ratio (WHR), waist to height ratio (WHtR), abdominal volume index (AVI) and conicity index (CI) for diagnosis of at least two other components of MetS. Youden index was used to determine the optimal cutoff points.

RESULTS

While the optimal cutoff points in men were 26.0kg/m² for BMI, 90cm for WC, 0.90 for WHR, 0.53 for WHtR, 16.6 (cm²) for AVI and 1.24(m³²/kg¹²) for CI, the optimal values in women were 29.0kg/m² for BMI, 91cm for WC, 0.86 for WHR, 0.58 for WHtR, 17.0(cm²) for AVI and 1.23 (m³²/kg¹²) for CI. The prevalence of overweight or obesity was 46.1% to 54.1% in women and 49.5% to 53.6% in men based on various obesity indexes. The area under the ROC curves (AUCs) varied from 0.671(0.651-0.690) for CI to 0.718(0.700-0.736) for WC in men and from 0.668 (0.646-0.690) for BMI to 0.755(0.735-0.774) for WHR and CI in women.

CONCLUSION

Except for CI in men and BMI in women, other obesity indexes were good discriminator in the diagnosis of the MetS.

The effects of high-intensity interval training vs. moderate-intensity continuous training on body composition in overweight and obese adults: a systematic review and meta-analysis

OBJECTIVE

The objective of this study is to compare the effects of high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) for improvements in body composition in overweight and obese adults.

METHODS

Trials comparing HIIT and MICT in overweight or obese participants aged 18-45 years were included. Direct measures (e.g. whole-body fat mass) and indirect measures (e.g. waist circumference) were examined.

RESULTS

From 1,334 articles initially screened, 13 were included. Studies averaged 10 weeks × 3 sessions per week training. Both HIIT and MICT elicited significant (p < 0.05) reductions in whole-body fat mass and waist circumference. There were no significant differences between HIIT and MICT for any body composition measure, but HIIT required ~40% less training time commitment. Running training displayed large effects on whole-body fat mass for both HIIT and MICT (standardized mean difference -0.82 and -0.85, respectively), but cycling training did not induce fat loss.

CONCLUSIONS

Short-term moderate-intensity to high-intensity exercise training can induce modest body composition improvements in overweight and obese individuals without accompanying body-weight changes. HIIT and MICT show similar effectiveness across all body composition measures suggesting that HIIT may be a time-efficient component of weight management programs.

The clinical importance of quantifying body fat distribution during androgen deprivation therapy for prostate cancer

Androgen deprivation therapy (ADT) is now considered a mainstay in the treatment of metastatic and locally advanced prostate cancer (PCa). Despite well-established benefits of ADT in relation to overall survival, this treatment has been associated with a number of adverse effects, particularly with regard to key cardiometabolic risk factors including the development of insulin resistance, dyslipidemia and increases in total and regional fat mass. In non-ADT populations, increased levels of visceral adipose tissue (VAT) are thought to be a key mediator of the increased cardiometabolic risk associated with weight gain, but this has received limited attention in men treated with ADT. VAT is best assessed using tools such as computed tomography or magnetic resonance imaging; however, these tools are not readily accessible for the majority of researchers or clinicians. Recent advances allow for a method of estimating VAT using a whole-body dual-energy X-ray absorptiometry (DXA) scan that shows promise as a practical tool for researchers to evaluate changes in body fat distribution during ADT. The aim of this narrative review is to (1) review the available evidence with regard to the relationship between ADT and cardiometabolic risk; (2) discuss the role of body fat distribution on cardiometabolic risk in non-ADT populations, with a particular emphasis on the importance of visceral adiposity; (3) examine the potential influence of ADT on body fat distribution and visceral adiposity and (4) provide an overview of current tools used to measure changes in body fat distribution in men treated with ADT, highlighting the potential utility of a recently developed DXA-derived measure of VAT.

Common Medications Which Lead to Unintended Alterations in Weight Gain or Organ Lipotoxicity

Obesity is one of the most common chronic conditions in the world. Its management is difficult, partly due to the multiple associated comorbidities including fatty liver, diabetes, hypertension, and hyperlipidemia. As a result, the choice of prescription medications in overweight and obese patients has important implications as some of them can actually worsen the fat accumulation and its associated metabolic complications. Several prescription medications are associated with weight gain with mechanisms that are often poorly understood and under-recognized. Even less data are available on the distribution of fat and lipotoxicity (the organ damage related to fat accumulation). The present review will discuss the drugs associated with weight gain, their mechanism of action, and the magnitude and timing of their effect.

Waist Circumference, Body Mass Index, and ESRD in the REGARDS (Reasons for Geographic and Racial Differences in Stroke) Study

BACKGROUND

The association between waist circumference and end-stage renal disease (ESRD) remains poorly explored.

STUDY DESIGN

Longitudinal population-based cohort.

SETTING & PARTICIPANTS

Participants in the REGARDS (Reasons for Geographic and Racial Differences in Stroke) Study (n=30,239) with information for body mass index (BMI), waist circumference, spot urine albumin-creatinine ratio (ACR), and estimated glomerular filtration rate (eGFR; n=26,960).

PREDICTOR

Elevated waist circumference or BMI.

OUTCOMES & MEASUREMENTS

Incident cases of ESRD were identified through linkage of REGARDS participants with the US Renal Data System.

RESULTS

Mean baseline age was 64.8 years, 45.8% were men, and 40.3% were black. Overall, 297 (1.1%) individuals developed ESRD during a median of 6.3 years. After adjustment for all covariates including waist circumference, no significant association was noted between BMI categories and ESRD incidence compared to BMI of 18.5 to 24.9 kg/m2 (referent). Higher waist circumference categories showed significantly increased hazard rates of ESRD, with waist circumference ≥ 108 cm in women and ≥122 cm in men (highest category) showing a 3.97-fold higher hazard rate (95% CI, 2.10-6.86) for ESRD compared to waist circumference < 80 cm in women and <94 cm in men (referent) after adjusting for demographic factors and BMI. However, no significant association was noted between any waist circumference category and ESRD incidence after adjustment for obesity-associated comorbid conditions and baseline ACR and eGFR.

LIMITATIONS

Short follow-up period (6.3 years) to assess ESRD risk among adults with eGFRs>60 mL/min/1.73 m2.

CONCLUSIONS

In this cohort of older adults, obesity as measured by waist circumference is associated with higher ESRD risk even with adjustment for BMI, whereas obesity as measured by BMI is not associated with higher ESRD risk after adjustment for waist circumference. However, no significant association is noted between increased waist circumference and ESRD risk after adjustment for obesity-related comorbid conditions, eGFR, and ACR.

Predictors of Treatment Response to Tesamorelin, a Growth Hormone-Releasing Factor Analog, in HIV-Infected Patients with Excess Abdominal Fat

BACKGROUND

Tesamorelin, a synthetic analog of human growth hormone-releasing factor, decreases visceral adipose tissue (VAT) in human immunodeficiency virus (HIV)-infected patients with lipodystrophy.

OBJECTIVES

1) To evaluate the utility of patient characteristics and validated disease-risk scores, namely indicator variables for the metabolic syndrome defined by the International Diabetes Federation (MetS-IDF) or the National Cholesterol Education Program (MetS-NCEP) and the Framingham Risk Score (FRS), as predictors of VAT reduction during tesamorelin therapy at 3 and 6 months, and 2) To explore the characteristics of patients who reached a threshold of VAT <140 cm2, a level associated with lower risk of adverse health outcomes, after 6 months of treatment with tesamorelin.

METHODS

Data were analyzed from two Phase 3 studies in which HIV-infected patients with excess abdominal fat were randomized in a 2:1 ratio to receive tesamorelin 2 mg (n = 543) or placebo (n = 263) subcutaneously daily for 6 months, using ANOVA and ANCOVA models.

RESULTS

Metabolic syndrome (MetS-IDF or MetS-NCEP) and FRS were significantly associated with VAT at baseline. Presence of metabolic syndrome ([MetS-NCEP), triglyceride levels >1.7 mmol/L, and white race had a significant impact on likelihood of response to tesamorelin after 6 months of therapy (interaction p-values 0.054, 0.063, and 0.025, respectively). No predictive factors were identified at 3 months. The odds of a VAT reduction to <140 cm2 for subjects treated with tesamorelin was 3.9 times greater than that of subjects randomized to placebo after controlling for study, gender, baseline body mass index (BMI) and baseline VAT (95% confidence interval [CI] 2.03; 7.44).

CONCLUSIONS

Individuals with baseline MetS-NCEP, elevated triglyceride levels, or white race were most likely to experience reductions in VAT after 6 months of tesamorelin treatment. The odds of response of VAT <140 cm2 was 3.9 times greater for tesamorelin-treated patients than that of patients receiving placebo.

Comparing measures of overall and central obesity in relation to cardiometabolic risk factors among US Hispanic/Latino adults

OBJECTIVE

US Hispanics/Latinos have high prevalence of obesity and related comorbidities. We compared overall and central obesity measures in associations with cardiometabolic outcomes among US Hispanics/Latinos.

METHODS

Multivariable regression assessed cross-sectional relationships of six obesity measures with cardiometabolic outcomes among 16,415 Hispanics/Latinos aged 18-74 years.

RESULTS

BMI was moderately correlated with waist-to-hip ratio (WHR; women, r = 0.37; men, r = 0.58) and highly correlated with other obesity measures (r ≥ 0.87) (P < 0.0001). All measures of obesity were correlated with unfavorable levels of glycemic traits, blood pressure, and lipids, with similar r-estimates for each obesity measure (P < 0.05). Multivariable-adjusted prevalence ratios (PRs) for diabetes (women, 6.7 [3.9, 11.5]; men, 3.9 [2.2, 6.9]), hypertension (women, 2.4 [1.9, 3.1]; men, 2.5 [1.9, 3.4]), and dyslipidemia (women, 2.1 [1.8, 2.4]; men, 2.2 [1.9, 2.6]) were highest for individuals characterized as overweight/obese (BMI ≥ 25 kg/m(2)) and with abnormal WHR (women ≥0.85; men, ≥0.90), compared with those with normal BMI and WHR (P < 0.0001). Among normal-weight individuals, abnormal WHR was associated with increased cardiometabolic condition prevalence (P < 0.05), particularly diabetes (women, PR = 4.0 [2.2, 7.1]; men, PR = 3.0 [1.6, 5.7]).

CONCLUSIONS

Obesity measures were associated with cardiometabolic risk factors to a similar degree in US Hispanics/Latinos. WHR is useful to identify individuals with normal BMI at increased cardiometabolic risk.

Imaging methods for analyzing body composition in human obesity and cardiometabolic disease

Advances in the technological qualities of imaging modalities for assessing human body composition have been stimulated by accumulating evidence that individual components of body composition have significant influences on chronic disease onset, disease progression, treatment response, and health outcomes. Importantly, imaging modalities have provided a systematic method for differentiating phenotypes of body composition that diverge from what is considered normal, that is, having low bone mass (osteopenia/osteoporosis), low muscle mass (sarcopenia), high fat mass (obesity), or high fat with low muscle mass (sarcopenic obesity). Moreover, advances over the past three decades in the sensitivity and quality of imaging not just to discern the amount and distribution of adipose and lean tissue but also to differentiate layers or depots within tissues and cells is enhancing our understanding of distinct mechanistic, metabolic, and functional roles of body composition within human phenotypes. In this review, we focus on advances in imaging technologies that show great promise for future investigation of human body composition and how they are being used to address the pandemic of obesity, metabolic syndrome, and diabetes.

α-Lipoic acid as a triglyceride-lowering nutraceutical

Considering the current obesity epidemic in the United States (>100 million adults are overweight or obese), the prevalence of hypertriglyceridemia is likely to grow beyond present statistics of ∼30% of the population. Conventional therapies for managing hypertriglyceridemia include lifestyle modifications such as diet and exercise, pharmacological approaches, and nutritional supplements. It is critically important to identify new strategies that would be safe and effective in lowering hypertriglyceridemia. α-Lipoic acid (LA) is a naturally occurring enzyme cofactor found in the human body in small quantities. A growing body of evidence indicates a role of LA in ameliorating metabolic dysfunction and lipid anomalies primarily in animals. Limited human studies suggest LA is most efficacious in situations where blood triglycerides are markedly elevated. LA is commercially available as dietary supplements and is clinically shown to be safe and effective against diabetic polyneuropathies. LA is described as a potent biological antioxidant, a detoxification agent, and a diabetes medicine. Given its strong safety record, LA may be a useful nutraceutical, either alone or in combination with other lipid-lowering strategies, when treating severe hypertriglyceridemia and diabetic dyslipidemia. This review examines the current evidence regarding the use of LA as a means of normalizing blood triglycerides. Also presented are the leading mechanisms of action of LA on triglyceride metabolism.

Apolipoprotein C-III: a potent modulator of hypertriglyceridemia and cardiovascular disease

PURPOSE OF REVIEW

The purpose of this article is to summarize the recent epidemiological, basic science, and pharmaceutical research linking apolipoprotein C-III (apoC-III) with the development and treatment of cardiovascular disease (CVD).

RECENT FINDINGS

ApoC-III is an important emerging target linking hypertriglyceridemia with CVD. ApoC-III is a potent modulator of many established CVD risk factors, and is found on chylomicrons, very-low density lipoprotein, low-density lipoprotein, and high-density lipoprotein particles. Recent studies show that in humans, apoC-III levels are an independent risk factor for CVD, and its presence on lipoproteins may promote their atherogenicity. This year, two large-scale epidemiological studies have linked mutations in apoC-III with increased incidence of CVD and hypertriglyceridemia. ApoC-III raises plasma triglycerides through inhibition of lipoprotein lipase, stimulation of very-low density lipoprotein secretion, and is a novel factor in modulating intestinal triglyceride trafficking. ApoC-III also stimulates inflammatory processes in the vasculature and the pancreas. The combination of raising plasma triglycerides and independently stimulating inflammatory processes makes apoC-III a valuable target for reducing the residual CVD risk in patients already on statin therapy, or for whom triglycerides are poorly controlled. Clinical trials on apoC-III antisense oligonucleotides are in progress.

SUMMARY

ApoC-III is a potent direct modulator of established CVD risk factors: plasma triglycerides and inflammation. Recent findings show that changes in apoC-III levels are directly associated with changes in cardiovascular risk and the atherogenicity of the lipoproteins on which apoC-III resides. Emerging roles of apoC-III include a role in directing the atherogenicity of high-density lipoprotein, intestinal dietary triglyceride trafficking, and modulating pancreatic β-cell survival. The combination of these roles makes apoC-III an important therapeutic target for the management and prevention of CVD.

Soft drink consumption is positively associated with increased waist circumference and 10-year incidence of abdominal obesity in Spanish adults

BACKGROUND

The accumulation of abdominal fat increases risk of metabolic disorders and premature death. There is a dearth of prospective data on the association between caloric beverage consumption and surrogate markers of abdominal adiposity.

OBJECTIVE

The aim of this study was to assess the relation between consumption of nonalcoholic caloric beverages, including soft drinks, fruit juice, whole milk, and skim and low-fat milk, and changes in waist circumference (WC) and odds of 10-y incidence of abdominal obesity.

METHODS

We conducted a prospective, population-based study of 2181 Spanish men and women aged 25-74 y who were followed from 2000 to 2009. We measured weight, height, and WC, and recorded data on diet and leisure-time physical activity (LTPA) with the use of validated questionnaires. We fit multivariable linear and logistic regression models.

RESULTS

A 100 kcal increase in soft drink consumption was associated with a 1.1 cm increase in WC (P = 0.018) after 10 y of follow-up. Substitution of 100 kcal of soft drinks with 100 kcal of whole milk or 100 kcal of juice was associated with a 1.3 cm (95% CI: 0.3, 2.4) and 1.1 cm (95% CI: 0.03, 2.2) decrease in WC, respectively. Increasing consumption of soft drinks from baseline to follow-up led to WC gain compared with maintaining nonconsumption. Greater soft drink consumption was positively associated (P = 0.029) with increased odds of 10-y incidence of abdominal obesity.

CONCLUSION

Adults' consumption of soft drinks was associated with increased WC and odds of 10-y incidence of abdominal obesity. This association was moderate but consistent in all statistical models.

Predictors for glucose change in hypertensive participants following short-term treatment with atenolol or hydrochlorothiazide

STUDY OBJECTIVE

To develop and validate a predictive model for glucose change and risk for new-onset impaired fasting glucose in hypertensive participants following treatment with atenolol or hydrochlorothiazide (HCTZ).

DESIGN

Randomized multicenter clinical trial.

PATIENTS

A total of 735 white or African-American men and women with uncomplicated hypertension.

MEASUREMENTS AND MAIN RESULTS

Pharmacogenomic Evaluation of Antihypertensive Responses (PEAR) is a randomized clinical trial to assess the genetic and nongenetic predictors of blood pressure response and adverse metabolic effects following treatment with atenolol or HCTZ. To develop and validate predictive models for glucose change, PEAR participants were randomly divided into a derivation cohort of 367 and a validation cohort of 368. Linear and logistic regression modeling were used to build models of drug-associated glucose change and impaired fasting glucose (IFG), respectively, in the derivation cohorts. These models were then evaluated in the validation cohorts. For glucose change after atenolol or HCTZ treatment, baseline glucose was a significant (p<0.0001) predictor, explaining 13% of the variability in glucose change after atenolol and 12% of the variability in glucose change after HCTZ. Baseline glucose was also the strongest and most consistent predictor (p<0.0001) for development of IFG after atenolol or HCTZ monotherapy. The area under the receiver operating curve was 0.77 for IFG after atenolol and 0.71 after HCTZ treatment, respectively.

CONCLUSION

Baseline glucose is the primary predictor of atenolol or HCTZ-associated glucose increase and development of IFG after treatment with either drug.

Primary care-based, targeted screening programme to promote sustained weight management

OBJECTIVE

To identify overweight and obese subjects at increased cardiovascular risk in the community, and provide them with lifestyle counselling that is possible to implement in real life.

DESIGN

Longitudinal cohort study.

SETTING

The communities of Harjavalta and Kokemäki in south-western Finland.

SUBJECTS

A tape for measurement of waist and a risk factor questionnaire was mailed to home-dwelling inhabitants aged 45-70 years (n = 6013). Of the 4421 respondents, 2752 with at least one cardiovascular risk factor were examined by a public health nurse. For the subjects with high cardiovascular risk (n = 1950), an appointment with a physician was scheduled. The main goal of lifestyle counselling for the 1608 high-risk subjects with BMI ≥ 25 kg/m(2) was weight reduction of at least 5%. Among these, 906 had completed self-administrated questionnaires at baseline and form the present study population.

MAIN OUTCOME MEASURE

Success in weight management.

RESULTS

At the three-year follow-up visit, 18% of subjects had lost ≥ 5% of their initial weight and 70% had stabilized their weight, while 12% had gained weight ≥ 5%. Newly diagnosed glucose disorder (OR 1.37 [95% CI 1.02-1.84]) predicted success in weight management, whereas depressive symptoms (OR 0.61 [95% CI 0.42-0.90]), excess alcohol use (OR 0.63 [95% CI 0.44-0.90]), and number of drugs used (OR 0.91 [95% CI 0.83-0.99]) at baseline predicted poor outcome.

CONCLUSIONS

A primary care screening programme to identify overweight or obese individuals can promote sustained weight management. Psychological factors, especially depressive symptoms, are a critical component to consider before attempts to change the lifestyle of an individual.

Skeletal muscle adiposity is associated with serum lipid and lipoprotein levels in Afro-Caribbean men

OBJECTIVE

When compared with other ethnic groups, African ancestry individuals have lower triglycerides and higher High-density lipoprotein cholesterol (HDL-C) levels, although the mechanisms for these differences remain unclear. A comprehensive array of factors potentially related to fasting serum lipid and lipoprotein levels in African ancestry men was evaluated.

DESIGN AND METHODS

Men (1,821) underwent dual-energy X-ray absorptiometry measures of total body fat and quantitative computed tomography assessments of calf skeletal muscle adiposity [subcutaneous and intermuscular adipose tissue (AT), and muscle density as a measure of intra-muscular AT].

RESULTS

Multivariable linear regression analysis identified age (-), total body fat (+), subcutaneous AT (-), fasting glucose (+), fasting insulin (+), diastolic blood pressure (+), and non-African ancestry (+) as independent correlates of triglycerides (all P < 0.05). Total body fat (+), intra-muscular AT (-), and diastolic blood pressure (+) were independent correlates of Low-density lipoprotein cholesterol (LDL-C) (all P < 0.001). Age (+), waist circumference (-), fasting insulin (-), physical activity (+), and alcohol intake (+) were independent correlates of HDL-C (all P < 0.05).

CONCLUSIONS

A novel relationship between skeletal muscle adiposity and serum lipid and lipoprotein levels in African ancestry men, independent of total and central adiposity was illuminated. In African ancestry populations, genetic factors are likely a significant determinant of triglycerides levels.

Impact of body mass index and waist circumference on the cardiovascular risk and all-cause death in a general population: data from the PAMELA study

BACKGROUND AND AIMS

Elevated values of body mass index (BMI) and waist circumference (WC) are associated with an augmented cardiovascular (CV) risk. It is debated, however, whether and to what extent this depends on the body fat increase 'per se' or on the related cardiometabolic alterations.

METHODS AND RESULTS

In 2005 subjects randomly selected from the general population of Monza (Italy), we assessed BMI, WC, office, home and 24 h blood pressure (BP), heart rate and metabolic variables. The impact of BMI and WC on the incidence of CV events, CV and all-cause mortality was estimated during a 148-month follow-up. Progressively higher values of BMI and WC were associated with a progressive increase in office, home and 24 h BP and in erratic BP variability (P < 0.0001 for trend). Metabolic variables were directly and significantly (P < 0.0001) related to BMI and WC, while an inverse significant relationship was detected with high-density lipoprotein (HDL)-cholesterol. The incidence of CV events, CV and all-cause deaths increased progressively from the lowest to the highest quintile of BMI and WC (P for trend always <0.005). Baseline BMI and WC higher by respectively 1 kg m⁻² and 1 cm were associated with an increased risk of CV events, CV and all-cause death by 8%, 12% and 7% (for baseline BMI) and 4%, 5% and 4% (for baseline WC), respectively. After adjustment for confounders, only the increased risk of CV death related to higher baseline BMI remained significant (hazard ratio (HR) 1.062, confidence interval (CI) 95% 1.003-1.126, P < 0.05).

CONCLUSION

The adverse prognostic impact of the accumulation of body fat is mediated by the associated haemodynamic and metabolic alterations. Baseline values of BMI, however, are an independent predictor of CV mortality.

Thermogenesis-based interventions for obesity and Type 2 diabetes mellitus

Obesity is one of the key noncommunicable diseases leading to significant comorbidities. In recent years, obesity has become a major public health issue and has threatened the wellbeing of millions of patients. Although there are multiple reasons for people becoming obese, sustained positive energy balance - energy intake is greater than energy expenditure - is the key for accumulating excess bodyfat. Prevention of obesity by lifestyle changes, healthy eating and increased physical activity are more cost effective than pharmacotherapy, bariatric surgery or ultimately treating complications of Type 2 diabetes mellitus (T2DM). Not all patients with obesity experience complications such as T2DM. The distribution of bodyfat is important in determining whether a person is obese and healthy or needs medical attention; however, the use of BMI alone will not differentiate this. Obesity patients with excess abdominal fat have the highest risk for T2DM, insulin resistance and thus, higher incidence of cardiovascular diseases. Obesity-associated complications can be reversed through healthy eating habits and increased duration and intensity of physical activity. Increasing work- and leisure-related physical activities increase the energy expenditure, having salutary effects on weightloss programs. Although treating symptoms of obesity and related disorders is important, it is not a solution for the obesity epidemic. Causes that lead to weight-gain need to be identified in individual patients, who should be educated about the causes of weight gain and ways to prevent it, and be provided with simple and practical interventions to lose weight.

DPP-4 Inhibitors as Therapeutic Modulators of Immune Cell Function and Associated Cardiovascular and Renal Insulin Resistance in Obesity and Diabetes

The prevalence of obesity and diabetes continues to rise in the United States and worldwide. These findings parallel the expansion of childhood obesity and diabetes. Obesity is a central component of the cardiorenal metabolic syndrome (CRS) which increases the risk for cardiovascular disease (CVD) and chronic kidney disease (CKD). The hallmark of obesity, CRS, and early type 2 diabetes is insulin resistance, a result of decreased insulin metabolic signaling due, in part, to enhanced serine phosphorylation and/or proteasome-mediated degradation of the insulin receptor substrate. Cardiovascular and renal insulin resistance significantly contributes to endothelial dysfunction, impaired cardiac diastolic and vascular relaxation, glomerular injury, and tubular dysfunction. In this context, multiple factors including oxidative stress, increased inflammation, and inappropriate activation of the renin-angiotensin-aldosterone and the sympathetic nervous system contribute to overweight- and obesity-induced systemic and tissue insulin resistance. One common link between obesity and the development of insulin resistance appears to be a low-grade inflammatory response resulting from dysfunctional innate and adaptive immunity. In this regard, there has been recent work on the role of dipeptidyl peptidase-4 (DPP-4) in modulating innate and adaptive immunity. The direct effects of DPP-4 on immune cells and the indirect effects through GLP-1-dependent and -independent pathways suggest effects of DPP-4 inhibition may have beneficial effects beyond glycemic control in improving CVD and renal outcomes. Accordingly, this review addresses new insights into the role of DPP-4 in immune modulation and the potential beneficial effects of DPP-4 inhibitors in insulin resistance and associated CVD and CKD prevention.

Direct and indirect effects of obesity on the kidney

Over the last few decades, much of the world has experienced an epidemic of obesity. In the year 2008, 1.4 billion people worldwide were overweight, and 500 million were obese. Even more alarming is a fact that in the year 2010, 40 million children under the age of 5 years were overweight or obese. In the same time period, the incidence of CKD has also increased worldwide. Obesity has been recognized as a driving force of another global epidemic-diabetes, the leading cause of ESRD. Recent studies are confirming that in addition to risk associated with diabetes per se, increased body mass index is independently linked to increased risk for various kidney disorders, prominently CKD, but also renal cell carcinoma and nephrolithiasis. The purpose of this article is to review current knowledge regarding adverse effects of obesity on the kidney.

Abdominal obesity, body mass index, and hypertension in US adults: NHANES 2007-2010

BACKGROUND

Both abdominal obesity, defined as waist circumference (WC) ≥ 102 cm for men and WC ≥ 88 cm for women and increased body mass index (BMI; kg/m²) are known to be associated with hypertension. The aim of this study was to examine the independent and the combined relationship between abdominal obesity and increased BMI and hypertension by age, race, and gender in a national sample.

METHODS

This report is based on national level cross-sectional data for adults aged 18 years and older (11,145 participants) from the US National Health and Nutrition Examination Survey (NHANES) 2007-2010.

RESULTS

Abdominal obesity, after adjusting for BMI categories and other covariables, was independently associated with hypertension. That is, survey participants classified as abdominally obese had almost 50% increased odds of being hypertensive (odds ratio (OR) 1.51, 95% confidence interval (CI) 1.27-1.81) after controlling for BMI. After adjusting for covariables, the groups of individuals classified as abdominally obese and normal BMI; as abdominally obese and overweight; and abdominally obese and obese each had a progressive increase in the odds of hypertension when compared with individuals who had a normal BMI and no abdominal obesity (OR 1.81, 95% CI 1.28-2.57, OR 1.87, 95% CI 1.55-2.25, and OR 3.23, 95% CI 2.63-3.96, respectively).

CONCLUSIONS

Abdominal obesity is independently associated with hypertension after adjusting for BMI. After adjusting for covariables and parameterizing BMI categories and abdominal obesity the new variable showed a progressive increase in the odds of hypertension. Both BMI and WC should be included in models assessing hypertension risks.

The effects of daily consumption of grapefruit on body weight, lipids, and blood pressure in healthy, overweight adults

Folklore has suggested that consuming grapefruit may promote weight control. Sparse data exist to support this hypothesis, although there is some evidence of health promotion effects with regard to blood pressure control and modulation of circulating lipids. The aim of this randomized controlled trial was to prospectively evaluate the role of grapefruit in reducing body weight and blood pressure and in promoting improvements in the lipid profile in overweight adults (N = 74). Following a 3-week washout diet low in bioactive-rich fruits and vegetables, participants were randomized to either the control diet (n = 32) or daily grapefruit (n = 42) in the amount of one half of a fresh Rio-Red grapefruit with each meal (3× daily) for 6 weeks. No differences between group in weight, blood pressure, or lipids were demonstrated. Grapefruit consumption was associated with modest weight loss (-0.61 ± 2.23 kg, P = .097), a significant reduction in waist circumference (-2.45 ± 0.60 cm, P = .0002), and a significant reduction in systolic blood pressure (-3.21 ± 10.13 mm Hg, P = .03) compared with baseline values. Improvements were observed in circulating lipids of those consuming grapefruit, with total cholesterol and low-density lipoprotein significantly decreasing by -11.7 mg/dL (P = .002) and -18.7 mg/dL (P < .001), respectively, compared with baseline values. This study suggests that consumption of grapefruit daily for 6 weeks does not significantly decrease body weight, lipids, or blood pressure as compared with the control condition. However, the improvements in blood pressure and lipids demonstrated in the intervention group suggest that grapefruit should be further evaluated in the context of obesity and cardiovascular disease prevention.

The protective effects of green tea polyphenols: lipid profile, inflammation, and antioxidant capacity in rats fed an atherogenic diet and dextran sodium sulfate

Acute and chronic inflammation and dyslipidemia play a critical role in the development of various diseases, including cardiovascular disease. Green tea polyphenols possess potent antioxidative and anti-inflammatory properties that contribute to the beneficial effects on heart health. The present study was carried out to determine if administration of a green tea extract (Polyphenon(®) E [PPE]; Mitsui Norin Co., Ltd., Tokyo, Japan) at 0.2% in the diet reduces cardiovascular risk factors, including dyslipidemia, inflammation, adiposity, and oxidative stress, in rats fed an atherogenic (high fat, cholesterol, and sugar) diet with dextran sodium sulfate (DSS) in drinking water. DSS treatment increased serum total cholesterol, low-density lipoprotein (LDL)-cholesterol, C-reactive proteins (CRP), and markers of liver toxicity and decreased high-density lipoprotein (HDL)-cholesterol significantly. Adding PPE to the atherogenic diet (PPE-diet) was associated with lower total cholesterol and LDL-cholesterol (P<.001) and increased HDL-cholesterol (P=.001). In addition, the PPE-diet was associated with decreased serum CRP concentration (P=.023) and increased total antioxidant capacity (P=.016) and catalase (P=.001) and glutathione peroxidase (P=.050) activities. The PPE-diet significantly lowered epididymal fat pad weight (P=.009). Feeding the PPE-diet also ameliorated some of the DSS-induced lipid, inflammatory, and oxidative symptoms. In summary, green tea supplementation decreased several cardiovascular risk factors, including body composition, dyslipidemia, inflammatory status, and antioxidant capacity, in rats fed an atherogenic diet. This study supports green tea as an effective dietary component for sustaining cardiovascular health.

Development and application of biological age prediction models with physical fitness and physiological components in Korean adults

BACKGROUND

Several biological age (BA) prediction models have been suggested with a variety of biomarkers. Valid models should be able to measure BA in a relatively short time period and predict subsequent physiological capability. Physiological and physical fitness variables have been shown to be distinctive markers for predicting BA and morbidity. The practical and noninvasive nature of such variables makes them useful as clinical assessment tools in estimating BA for in-depth diagnosis and corresponding intervention.

OBJECTIVE

To identify, develop and evaluate biomarkers and BA prediction models and validate their clinical usefulness for the practical diagnosis of functional aging.

METHODS

Fourteen variables were measured in 3,112 male and 1,233 female participants aged 30 and older between the years 2004 and 2007. Through a series of parsimonious stepwise elimination processes, two sets of 8 gender-specific variables were selected as candidate biomarkers for 1,604 men and 760 women. Principal component analysis, linear regression analysis and adjustment methods were further applied to obtain two sets of true BA (TBA) prediction models. The TBA models were examined for validity by comparing TBA to the corresponding chronological age (CA) with clinical risk factors.

RESULTS

TBA prediction models with r(2) values of 0.638 and 0.672 were developed, each unique to men and women, respectively. The overall mean TBA and CA of the participants were 53.9 and 51.8 years, respectively, with a marginal difference of -2.1 and -1.3 years. The regression slopes or rates of TBA as a function of CA were 1.00 and 1.28 for men and women with r values of 0.799 and 0.820 (p < 0.001), respectively. In comparing TBA to CA rates between healthy and clinical risk groups, both sarcopenic and obese groups showed significant increases in TBA.

CONCLUSIONS

The selected biomarkers encompass various complex physiopathological factors related to intrinsic and extrinsic physiological and functional aging. The BA prediction models based on the selected biomarkers could be practical in assessing BA for Korean adults.

Prenatal Programming and Epigenetics in the Genesis of the Cardiorenal Syndrome

The presence of a group of interacting maladaptive factors, including hypertension, insulin resistance, metabolic dyslipidemia, obesity, and microalbuminuria and/or reduced renal function, collectively constitutes the cardiorenal metabolic syndrome (CRS). Nutritional and other environmental cues during fetal development can permanently affect the composition, homeostatic systems, and functions of multiple organs and systems; this process has been referred to as 'programming'. Since the original formulation of the notion that low birth weight is a proxy for 'prenatal programming' of adult hypertension and cardiovascular disease, evidence has also emerged for programming of kidney disease, insulin resistance, obesity, metabolic dyslipidemia, and other chronic diseases. The programming concept was initially predicated on the notion that in utero growth restriction due to famine was responsible for increased hypertension, and cardiovascular and renal diseases. On the other hand, we are now more commonly exposed to increasing rates of maternal obesity. The current review will discuss the overarching role of maternal overnutrition, as well as fetal undernutrition, in epigenetic programming in relation to the pathogenesis of the CRS in children and adults.

Association between adiposity indices and cardiometabolic risk factors among adults living in Puerto Rico

OBJECTIVE

To compare the general adiposity index (BMI) with abdominal obesity indices (waist circumference (WC), waist-to-hip ratio (WHR) and waist-to-height ratio (WHtR)) in order to examine the best predictor of cardiometabolic risk factors among Hispanics living in Puerto Rico.

DESIGN

Secondary analysis of measurements taken from a representative sample of adults. Logistic regression models (prevalence odds ratios (POR)), partial Pearson's correlations (controlling for age and sex) and receiver-operating characteristic (ROC) curves were calculated between indices of obesity (BMI, WC, WHR and WHtR) and blood pressure, HDL cholesterol (HDL-C), LDL cholesterol (LDL-C), total cholesterol (TC):HDL-C, TAG, fasting blood glucose, glycosylated Hb, high-sensitivity C-reactive protein (hs-CRP), fibrinogen, plasminogen activator inhibitor-1 (PAI-1) and an aggregated measure of cardiometabolic risk.

SETTING

Household study conducted between 2005 and 2007 in the San Juan Metropolitan Area in Puerto Rico.

SUBJECTS

A representative sample of 858 non-institutionalized adults.

RESULTS

All four obesity indices significantly correlated with the cardiometabolic risk factors. WHtR had the highest POR for high TC:HDL-C, blood pressure, hs-CRP, fibrinogen and PAI-1; WC had the highest POR for low HDL-C and high LDL-C and fasting blood glucose; WHR had the highest POR for overall cardiometabolic risk, TAG and glycosylated Hb. BMI had the lowest POR for most risk factors and smallest ROC curve for overall cardiometabolic risk.

CONCLUSIONS

The findings of the study suggest that general adiposity and abdominal adiposity are both associated with cardiometabolic risk in this population, although WC, WHR and WHtR appear to be slightly better predictors than BMI.

Abdominal obesity and age-related macular degeneration

Evidence for an association between age-related macular degeneration (AMD) and obesity is inconsistent. The authors examined associations between adiposity and AMD prevalence using 21,287 participants from the Melbourne Collaborative Cohort Study aged 40-69 years at baseline (1990-1994). For men, each increase of 0.1 in waist/hip ratio (~1 standard deviation) was associated with a 13% increase in the odds of early AMD (odds ratio = 1.13, 95% confidence interval: 1.01, 1.26; P = 0.03) and a 75% increase in the odds of late AMD (odds ratio = 1.75, 95% confidence interval: 1.11, 2.76; P = 0.02). No other adiposity measure was associated with early AMD for men. Smoking status modified the relation between waist/hip ratio and early AMD (P = 0.05), with no association for former smokers. For women, there were inverse associations with early AMD for all adiposity measures (odds ratios = 0.89-0.93; P = 0.002-0.02), but no associations were observed for late AMD. This study confirms abdominal obesity as an AMD risk factor for men despite a survivorship effect from competing risks in morbidity and mortality. The inverse associations for women may reflect weaker true positive associations with AMD that are insufficient to overcome the survivorship effect. New data are provided on complex interactions between environmental exposures and AMD risk.

Triglycerides and heart disease: still a hypothesis?

The purpose of this article is to review the basic and clinical science relating plasma triglycerides and cardiovascular disease. Although many aspects of the basic physiology of triglyceride production, its plasma transport, and its tissue uptake have been known for several decades, the relationship of plasma triglyceride levels to vascular disease is uncertain. Are triglyceride-rich lipoproteins, their influence on high-density lipoprotein and low-density lipoprotein, or the underlying diseases that lead to defects in triglyceride metabolism the culprit? Animal models have failed to confirm that anything other than early fatty lesions can be produced by triglyceride-rich lipoproteins. Metabolic products of triglyceride metabolism can be toxic to arterial cells; however, these studies are primarily in vitro. Correlative studies of fasting and postprandial triglycerides and genetic diseases implicate very-low-density lipoprotein and their remnants and chylomicron remnants in atherosclerosis development, but the concomitant alterations in other lipoproteins and other risk factors obscure any conclusions about direct relationships between disease and triglycerides. Genes that regulate triglyceride levels also correlate with vascular disease. Human intervention trials, however, have lacked an appropriately defined population and have produced outcomes without definitive conclusions. The time is more than ripe for new and creative approaches to understanding the relationship of triglycerides and heart disease.

Renal function and severity of bright liver. Relationship with insulin resistance, intrarenal resistive index, and glomerular filtration rate

AIMS

Relationships of renal function and liver disease are described in acute and chronic liver failure. The aim of the study is to investigate which relationship, if any, is present between severity of non-alcoholic fatty liver disease (NAFLD), assessed by bright liver score (BLS) versus mild-moderate renal insufficiency assessed by glomerular filtration rate (GFR) and by ultrasound intra-renal arterial resistive index (RRI). Moreover, which difference, if any, can be found in NAFLD patients with normal versus increased transaminases.

PATIENTS

The study enrolled 323 NAFLD and 176 non-NAFLD consecutive patients, comparable for age, gender distribution, GFR, and RRI referred to a university clinical day hospital after an ultrasound diagnosis of bright liver, for clinical-nutritional counselling. Personalized computerized mediterranean diet, physical activity increase, and smoking withdrawal integrated counselling were provided.

RESULTS

In NAFLD patients, homoeostasis model (HOMA) has a significant correlation with BLS. According to the severity of BLS, grade II-III versus grade I patients have significantly higher values of HOMA, body mass index (BMI), triglycerides, and longitudinal right liver length. By odds ratio, more severe BLS, increased HOMA, and transaminases are associated with lower GFR. Increased transaminases are associated with higher grades of BLS, HOMA, and BMI. By multiple linear regression waist-to-hip ratio, RRI, and BLS, as significant independent factors (p < 0.0001), explain significantly variance to GFR. This is not observed in normal control group, in which only RRI is a factor explaining GFR.

CONCLUSION

Greater RRI, abdominal obesity, and greater BLS account for a lower GFR in NAFLD patients suggesting the hypothesis that inter-related factors can be operating early in the natural history of obesity-related kidney and liver disease.

Overnutrition and the Cardiorenal Syndrome: Use of a Rodent Model to Examine Mechanisms

Obesity has reached epidemic proportions with far-reaching health care and economic implications. Overnutrition, characterized by excess intake of carbohydrates and fats, has been associated with end-organ damage in several tissues, including the heart and the kidney. Furthermore, overnutrition is one of the most important modifiable and preventable causes of morbidity and mortality associated with cardiovascular and kidney diseases. Insulin resistance and compensatory hyperinsulinemia as well as associated mechanisms, including enhanced renin-angiotensin-aldosterone system activity, inflammation, and oxidative stress, have been implicated in obesity-related cardiorenal injury. In this review, the effect of overnutrition on heart and kidney disease is assessed in a rodent model of overnutrition and obesity, the Zucker obese rat.

The Role of Overweight and Obesity in the Cardiorenal Syndrome

The presence of a group of interactive maladaptive factors including hypertension, insulin resistance, metabolic dyslipidemia, obesity, microalbuminuria, and/or reduced renal function constitute the cardiorenal metabolic syndrome (CRS). Overweight, obesity, and chronic kidney disease (CKD) have grown to pandemic proportions in industrialized countries during the past decade. The fact that these interactive factors promote heart and renal disease has been documented in large population-based studies. Obesity seems to be the driving force behind the development of heart disease and CKD and therefore the CRS. The relationship between overweight/obesity and kidney disease begins in early childhood and appears to be related to overconsumption of high-fructose corn syrup and insufficient physical activity. Today, 13 million children are obese, and over 70% of these children are likely to become obese adults. Indeed, approximately 30% of male and 34% of female adults in the United States are obese. This lifestyle-related epidemic will be a major societal medical and economic problem that will accentuate the current epidemic of CKD in the United States and other industrialized and emerging industrialized countries. In this article, we will review the potential mechanisms by which obesity and other metabolic abnormalities interact to promote heart and progressive kidney disease.

Body mass index, leptin, and ambulatory blood pressure variability in healthy adults

OBJECTIVE

To investigate the association between body mass index (BMI) and 24-h ambulatory blood pressure (ABP) variability, and to assess whether leptin might act as a mediator of this association.

METHODS

A cross-sectional study in healthy, normotensive men and women (n = 156). BMI was derived from direct height and weight measurements made on each participant. All participants underwent 24-h ABP monitoring, and two measures of ABP variability were derived--the weighted standard deviation (wSD) and the average real variability (ARV). Plasma leptin was measured using an enzyme lined immunosorbant assay.

RESULTS

In linear regression models adjusted for demographic factors, glucose, creatinine, lipids, and mean ABP, BMI showed positive and statistically significant associations with diastolic wSD, and systolic and diastolic ARV. For those in the low, intermediate, and high BMI groups, mean values for diastolic wSD were 7.7, 7.9, and 8.5 mmHg, respectively (p = .02); mean values of systolic ARV were 8.2, 8.2, and 9.0 mmHg, respectively (p=.02); and mean values of diastolic ARV were 6.7, 7.0, and 7.5 mmHg, respectively (p = .01). Similarly, leptin showed positive and statistically significant associations with measures of wSD and ARV. When BMI was entered as an ordinal variable in regression models for wSD and ARV, adjustment for leptin attenuated significant ordinal BMI coefficients by as much as 60%, suggesting a mediating role for leptin.

CONCLUSION

In healthy adults, BMI and leptin show positive associations with ABP variability, and leptin may play a mediating role in this association.

Racial/ethnic differences in the association of triglycerides with other metabolic syndrome components: the Multi-Ethnic Study of Atherosclerosis

OBJECTIVE

The aim of this study was to examine whether there are ethnic differences in the association of triglycerides (TG) with waist circumference (WC), blood pressure, high-density lipoprotein cholesterol (HDL-C), fasting glucose, and insulin resistance and to examine the disparities in the prevalence of the metabolic syndrome components between African Americans and non-Hispanic whites who do not have hypertriglyceridemia.

METHODS

This study used the baseline data from the Multi-Ethnic Study of Atherosclerosis (MESA) study. The analysis included non-Hispanic whites (N = 2,427) and African Americans (N = 1,519) aged 45-84 years free of clinically evident cardiovascular disease and diabetes at baseline. The revised National Cholesterol Education Program (NCEP) criteria were used to define the metabolic syndrome and its components.

RESULTS

African Americans had lower prevalence of elevated TG as compared with non-Hispanic whites. The association of TG with other components of the metabolic syndrome appeared to be similar between African Americans and non-Hispanic whites except for one. There was significant association of TG with WC among white women but not among African American women after adjusting for demographic and other variables (P for interaction of TG with ethnicity <0.001). In participants with TG < 150 mg/dL, African American women had higher prevalence rates than white women of abdominal obesity, elevated blood pressure, low HDL-C, elevated fasting glucose and homeostasis model assessment of insulin resistance (HOMA-IR). In men, the prevalence rates of high blood pressure, elevated fasting glucose, and HOMA-IR were significantly higher in African Americans than in whites.

CONCLUSIONS

The study findings suggest that further evaluation is warranted regarding the cutoffs for elevated TG and its clustering effect with other cardiometabolic risk factors on predicting risk for diabetes and cardiovascular disease (CVD) in African Americans.

Coronary heart disease and body fat distribution

Larger waist circumference or waist-hip ratio, as crude indicators of visceral fat mass, are associated with adverse metabolic profile, but their role in predicting future coronary heart disease (CHD) events has been less investigated. Recent epidemiologic findings suggest that these simple and inexpensive measures of abdominal fat distribution predict CHD independently of body mass index, and, to a certain extent, cardiovascular disease risk factors. The magnitude and shape of the association between abdominal adiposity and CHD have been shown to vary with age, gender, and ethnicity. Studies have also suggested that lower body fat is associated with reduced CHD risk, although the clinical relevance for this finding needs further elucidation. Assessing body fat distribution may be useful for improving CHD risk assessment, although more studies are needed to assess consistency in CHD risk predictions across populations. A consensus is also needed to define the clinically relevant cut-off points for waist circumference or waist-hip ratio.

Abnormalities in circadian blood pressure variability and endothelial function: pragmatic markers for adverse cardiometabolic profiles in asymptomatic obese adults

Background

Cardiovascular disease (CVD) risk, although perceived to be high, is often difficult to demonstrate in disease free (healthy) obese adults.

Hypothesis

Changes in circadian blood pressure variability (CBPV) and endothelial function (EF) may be early correlates of cardiometabolic disorders.

Methods

Asymptomatic men and women in 3 groups: normal weight (n = 10), overweight (n = 10) and obese (n = 15) were evaluated. Blood pressure and heart rate were recorded over 7 days: every 30 minutes during the day and every 60 minutes during the night, by automatic ambulatory monitoring. Resting EF was assessed in a fasting state between 8-10 AM by brachial ultrasound. Anthropometric and cardiometabolic indicators were measured and correlations with CBPV and EF were investigated.

Results

The 3 groups had (Mean(SD)) BMI: 22.6(1.6), 27(3) and 34(5) kg/m², respectively, weight: 64(16), 79(14), 95(16) kg and waist circumference: 79(9), 93(10), 107(13) cm. None in normal-weight or overweight groups had abnormal CBPV, while 8 of 15 obese adults had one or more CBPV abnormities (p < 0.05). Obese adults with CBPV abnormalities had elevated hs-CRP (15.3(9.3) mg/L), fibrinogen (593(97) mg/dl), fasting serum glucose (102(16) mg/dL), and cardiac risk ratios (Total-C/HDL-C: 5.2(1.9), LDL-C/HDL-C: 3.1(1.4)). Adults in the 3 respective groups who did not have CBPV abnormalities had flow-mediated brachial artery dilatation (FMD) of 0.22(0.06); 0.20(0.04), 0.23(0.02) mm over resting diameter. Obese participants with CBPV abnormalities (Mesor-hypotension, circadian hyper amplitude tension, elevated pulse pressure), had attenuated FMD at 78, 52, and 56% of resting reference diameter (means 0.18(0.07), 0.12(0.08), and 0.13(0.05) mm; p < 0.05), respectively.

Conclusions

Asymptomatic obese adults with abnormal CBPV and EF exhibit unfavorable cardiometabolic profiles.

Impact of waist circumference difference on health-care cost among overweight and obese subjects: the PROCEED cohort

OBJECTIVE

To estimate the incremental effect of waist circumference (WC) on health-care costs among overweight and obese subjects after adjusting for body mass index (BMI).

METHODS

A prospective study. The subjects were members of Internet panels in the United States (US) and Germany. 10,816 individuals (United States: n = 5410; Germany: n = 5406) aged 30-70 years with BMI scores between 20 and 35 kg/m(2) were recruited and grouped by category: healthy weight (BMI 20-24.9 kg/m(2)), overweight (BMI 25-29.9 kg/m(2)), and obese (BMI 30-35 kg/m(2)). Within the overweight and obese categories, the individuals were stratified by sex and within those subgroups, characterized as above or below the median WC. The subjects self-reported weight, WC, and health-care resource use at baseline, 3 months, and 6 months using online questionnaires. Over 65% of the recruited subjects completed all surveys. Resource utilization was translated into health-care costs by multiplying unit costs from national sources in each country. Annualized health costs were summarized for subjects with low and high WC within the overweight and obese categories. A two-part model generated predicted annual costs because of the WC difference controlling for BMI, demographic, and lifestyle variables among the overweight and obese subjects.

RESULTS

When BMI and other characteristics are constant, annual health-care costs are 16% to 18% higher in Germany and 20% to 30% higher in the United States for the subjects with a high WC compared with subjects with a low WC.

CONCLUSIONS

Targeting people with a high waist circumference for weight management whether they are overweight or obese may maximize cost-efficacy.