Abdominal adiposity is a stronger predictor of insulin resistance than fitness among 50-95 year olds

Psychosocial Disadvantage During Childhood and Midlife Health: NIMHD Social Epigenomics Program

Importance

Low childhood socioeconomic status (SES) is a social hallmark of aging that contributes to adult health disparities and earlier morbidity and mortality. Childhood perceptions of stress are associated with child health outcomes and may contribute to premature biological aging into adulthood.

Objective

To describe the association of childhood SES and perceived stress with midlife insulin resistance and epigenetic age and to explore whether late adolescent adiposity mediates the observed associations.

Design, Setting, and Participants

The longitudinal cohort National Heart, Lung, and Blood Institute Growth and Health Study enrolled girls aged 10 years from January 1987 to May 1988, and followed them up to 19 years of age. Participants from Richmond, California, were recruited again at midlife in 2016 to assess insulin resistance and epigenetic age. Analyses were conducted from August 2, 2023, to March 18, 2024. A total of 433 participants were eligible and included in the analyses (specific sample sizes ranged across analyses from 303 to 391).

Exposures

Childhood levels of SES at 10 years of age (parental educational level and income) and perceived stress at 11 years of age.

Main Outcomes and Measures

The hypotheses tested were formulated after data collection. Outcomes included the homeostatic model assessment of insulin resistance (HOMA-IR) and the GrimAge and DunedinPACE epigenetic clocks. Waist circumference in late adolescence was tested as a mediator.

Results

Among the 433 participants, the mean (SD) age was 39.4 (1.2) years; 218 (50.3%) were Black and 215 (49.7%) were White; and 135 (31.2%) had parents with a college degree or higher. Higher parental educational level was associated with lower HOMA-IR (B = -0.22 [95% CI, -0.41 to -0.02]; P = .03), lower midlife GrimAge (B = -1.76 [95% CI, -2.85 to -0.66] years; P = .002), and slower midlife DunedinPACE (B = -0.03 [95% CI, -6.29 to -0.002]; P = .04). Childhood perceived stress was indirectly associated through late adolescent adiposity with midlife HOMA-IR (B = 0.01 [95% CI, 0.001-0.01]; P = .02) and midlife GrimAge (B = 0.02 [95% CI, 0.003-0.04] years; P = .01).

Conclusions and Relevance

In this longitudinal cohort study of midlife health and aging, childhood social hallmarks of aging were associated with midlife insulin resistance and epigenetic age (GrimAge and DunedinPACE). Future studies should identify malleable factors that may slow the impact of social hallmarks of aging.

Glycaemic Status and Risk of Abdominal Aortic Aneurysm: A Nationwide Cohort Study of Four Million Adults using Korean National Health Screening Data

OBJECTIVE

This retrospective cohort study aimed to confirm the previously reported inverse association between diabetes mellitus (DM) and abdominal aortic aneurysm (AAA) using large population based data. It also investigated the associations between AAA and impaired fasting glucose (IFG) and new onset DM (not yet treated).

METHODS

A representative dataset was obtained from the Korean National Health Insurance Service. Participants who were aged ≥ 50 years and received a national health examination in 2009 were included and followed until 31 December 2019. Glycaemic status was defined based on fasting plasma glucose level and the relevant diagnostic codes. AAA was ascertained using medical facility use records with relevant diagnostic codes or aneurysm repair surgery. A Cox proportional hazards model was used to examine the association between glycaemic status and AAA, with adjustment for confounders. Additionally, the interactions between glycaemic status and subgroups based on baseline characteristics were examined.

RESULTS

The study population comprised 4 162 640 participants. Participants with IFG or DM were significantly more likely to be male, older, and have comorbidities compared with normoglycaemic participants at baseline. The incidence of AAA was lower in participants with IFG or DM compared with normoglycaemic participants. The AAA risk was lower in patients with DM than in patients with IFG, and decreased linearly according to glycaemic status: the adjusted hazard ratio was 0.88 (95% confidence interval [CI] 0.85 - 0.91) for IFG, 0.72 (95% CI 0.67 - 0.78) for newly diagnosed DM, 0.65 (95% CI 0.61 - 0.69) for DM duration < 5 years, and 0.47 (95% CI 0.44 - 0.51) for DM duration ≥ 5 years compared with the normoglycaemia group. Both IFG and DM were related to reduced AAA risk in all subgroups, suggesting an independent association.

CONCLUSION

Both IFG and DM, even when not treated with antihyperglycaemic medication, were associated with a lower incidence of AAA. The AAA risk decreased linearly according to DM duration.

The determinants of fasting and post-load non-esterified fatty acids in older adults: The cardiovascular health study

Aim

Non-esterified fatty acids (NEFA) are potential targets for prevention of key cardiometabolic diseases of aging, but their population-level correlates remain uncertain. We sought to identify modifiable factors associated with fasting and post-load NEFA levels in older adults.

Methods

We used linear regression to determine the cross-sectional associations of demographic, anthropometric, and lifestyle characteristics and medication use with serum fasting and post-load NEFA concentrations amongst community-dwelling older adults enrolled in the Cardiovascular Health Study (n = 1924).

Results

Fasting NEFA levels generally demonstrated a broader set of determinants, while post-load NEFA were more consistently associated with metabolic factors. Waist circumference and weight were associated with higher fasting and post-load NEFA. Cigarette smoking and caffeine intake were associated with lower levels of both species, and moderate alcohol intake was associated with higher fasting levels whereas greater consumption was associated with lower post-load levels. Unique factors associated with higher fasting NEFA included female sex, higher age, loop and thiazide diuretic use and calcium intake, while factors associated with lower fasting levels included higher educational attainment, beta-blocker use, and protein intake. Hours spent sleeping during the daytime were associated with higher post-load NEFA, while DASH score was associated with lower levels.

Conclusion

Fasting and post-load NEFA have both common and unique modifiable risk factors, including sociodemographics, anthropometric, medications, and diet. Post-load NEFA were particularly sensitive to metabolic factors, while a broader range of determinants were associated with fasting levels. These factors warrant study as targets for lowering levels of NEFA in older adults.

Sex differences in the association between dynapenic abdominal obesity and onset of disability in activities of daily living among adults aged ≥50 years: A prospective analysis of the Irish Longitudinal Study on Ageing

BACKGROUND

Sex differences in the longitudinal relationship between dynapenic abdominal obesity, i.e., impairment in muscle strength and high waist circumference, and disability in activities of daily living have not been investigated to date. Therefore, we aimed to examine sex differences in the longitudinal association between dynapenic abdominal obesity at baseline and the onset of disability in activities of daily living during a four-year follow-up period among Irish adults aged ≥50 years.

METHODS

Data from Wave 1 (2009-2011) and Wave 3 (2014-2015) of the Irish Longitudinal Study on Ageing survey were analyzed. Dynapenia was defined as handgrip strength of <26 kg for men and <16 kg for women. Abdominal obesity was defined as waist circumference of >88 cm for women and >102 cm for men. Dynapenic abdominal obesity was defined as having both dynapenia and abdominal obesity. Disability was defined as having difficulty with at least one of six activities of daily living (dressing, walking, bathing, eating, getting in or out of bed, using the toilet). Multivariable logistic regression was conducted to assess associations.

RESULTS

Data on 4471 individuals aged ≥50 years and free of disability at baseline were analyzed [mean (SD) age 62.3 (8.6) years; 48.3 % males]. In the overall sample, compared to no dynapenia and no abdominal obesity, dynapenic abdominal obesity was associated with 2.15 (95%CI = 1.17-3.93) times higher odds for incident disability at 4-year follow-up. This association was significant among men (OR = 3.78; 95%CI = 1.70-8.38) but not among women (OR = 1.34; 95%CI = 0.60-2.98).

CONCLUSIONS

Interventions to prevent or address dynapenic abdominal obesity may aid in the prevention of disability, especially among men.

Body size over the adult life course and the risk of colorectal cancer among postmenopausal women

OBJECTIVE

To assess the associations among several anthropometric measures, as well as BMI trajectories and colorectal cancer (CRC) risk in older women.

DESIGN

Prospective cohort study.

SETTING

Forty clinical centres in the USA.

PARTICIPANTS

Totally, 79 034 postmenopausal women in the Women's Health Initiative Observational Study.

RESULTS

During an average of 15·8 years of follow-up, 1514 CRC cases were ascertained. Five BMI trajectories over 18-50 years of age were identified using growth mixture model. Compared with women who had a normal BMI at age 18, women with obesity at age 18 had a higher risk of CRC (HR 1·58, 95 % CI 1·02, 2·44). Compared with women who kept relatively low normal body size during adulthood, women who progressed from normal to obesity (HR 1·29, 95 % CI 1·09, 1·53) and women who progressed from overweight to obesity (HR 1·37, 95 % CI 1·13, 1·68) had higher CRC risks. A weight gain > 15 kg from age 18 to 50 (HR 1·20, 95 % CI 1·04, 1·40) and baseline waist circumference > 88 cm (HR 1·33, 95 % CI 1·19, 1·49) were associated with higher CRC risks, compared with stable weight and waist circumference ≤ 88 cm, respectively.

CONCLUSION

Women who have a normal weight in early adult life and gain substantial weight later, as well as those who are persistently heavy over adulthood, demonstrated a higher risk of developing CRC. Our study highlights the importance of maintaining a healthy body weight over the life course for reducing the risk of developing CRC in women.

Changes in abdominal adipose tissue depots assessed by MRI correlate with hepatic histologic improvement in non-alcoholic steatohepatitis

BACKGROUND & AIMS

Non-alcoholic steatohepatitis (NASH) is prevalent in adults with obesity and can progress to cirrhosis. In a secondary analysis of prospectively acquired data from the multicenter, randomized, placebo-controlled FLINT trial, we investigated the relationship between reduction in adipose tissue compartment volumes and hepatic histologic improvement.

METHODS

Adult participants in the FLINT trial with paired liver biopsies and abdominal MRI exams at baseline and end-of-treatment (72 weeks) were included (n = 76). Adipose tissue compartment volumes were obtained using MRI.

RESULTS

Treatment and placebo groups did not differ in baseline adipose tissue volumes, or in change in adipose tissue volumes longitudinally (p = 0.107 to 0.745). Deep subcutaneous adipose tissue (dSAT) and visceral adipose tissue volume reductions were associated with histologic improvement in NASH (i.e., NAS [non-alcoholic fatty liver disease activity score] reductions of ≥2 points, at least 1 point from lobular inflammation and hepatocellular ballooning, and no worsening of fibrosis) (p = 0.031, and 0.030, respectively). In a stepwise logistic regression procedure, which included demographics, treatment group, baseline histology, baseline and changes in adipose tissue volumes, MRI hepatic proton density fat fraction (PDFF), and serum aminotransferases as potential predictors, reductions in dSAT and PDFF were associated with histologic improvement in NASH (regression coefficient = -2.001 and -0.083, p = 0.044 and 0.033, respectively).

CONCLUSIONS

In adults with NASH in the FLINT trial, those with greater longitudinal reductions in dSAT and potentially visceral adipose tissue volumes showed greater hepatic histologic improvements, independent of reductions in hepatic PDFF.

CLINICAL TRIAL NUMBER

NCT01265498.

IMPACT AND IMPLICATIONS

Although central obesity has been identified as a risk factor for obesity-related disorders including insulin resistance and cardiovascular disease, the role of central obesity in non-alcoholic steatohepatitis (NASH) warrants further clarification. Our results highlight that a reduction in central obesity, specifically deep subcutaneous adipose tissue and visceral adipose tissue, may be related to histologic improvement in NASH. The findings from this analysis should increase awareness of the importance of lifestyle intervention in NASH for clinical researchers and clinicians. Future studies and clinical practice may design interventions that assess the reduction of deep subcutaneous adipose tissue and visceral adipose tissue as outcome measures, rather than simply weight reduction.

The Acute Effects of Interrupting Prolonged Sitting Time in Adults with Standing and Light-Intensity Walking on Biomarkers of Cardiometabolic Health in Adults: A Systematic Review and Meta-analysis

Background

Increasing evidence highlights that accumulating sitting time in prolonged bouts is detrimental to cardiometabolic health.

Objectives

This systematic review aimed to compare the effects of fractionating prolonged sitting with frequent short bouts of standing and light-intensity walking on cardiometabolic health markers and conduct a meta-analysis for differences in systolic blood pressure (SBP), postprandial glucose and insulin.

Methods

Experimental randomised crossover trials with at least three intervention arms that assessed interrupting sitting with frequent short bouts of standing and light-intensity walking over a single day compared to a prolonged sitting condition were retrieved. These studies measured at minimum one marker of cardiometabolic health in adults > 18 years. An electronic search was completed on the 2nd of August 2021, searching PubMed and Web of Science Core Collection, Scopus, Embase, Cochrane Library and APA PsycINFO. Risk of bias was assessed using a modified Downs and Black checklist. A meta-analysis was conducted using calculated Cohen’s d quantifying the magnitude of difference between experimental conditions.

Results

Seven studies met the inclusion criteria for the systematic review. All seven studies were included within the meta-analysis for postprandial glucose, four studies were pooled for postprandial insulin and three for SBP. Biomarkers of cardiometabolic health were discussed qualitatively if fewer than three studies measured and reported the variable. A meta-analysis of seven acute, 1-day randomised crossover trials that sampled mixed-sex adults (aged > 18 years) who were predominately overweight or participants with obesity found that standing as an interruption to prolonged sitting significantly reduced postprandial glucose (∆ = − 0.31, 95% CI − 0.60, − 0.03; z = − 2.15, p < 0.04) but had no significant effect on insulin or SBP. Light-intensity walking was shown to significantly attenuate postprandial glucose (∆ = − 0.72, 95% CI − 1.03, − 0.41; z = − 4.57, p < 0.001) and insulin (∆ = − 0.83, 95% CI − 1.18, − 0.48; z = − 4.66, p < 0.001) compared to continued sitting. When comparing light-intensity walking breaks compared to standing breaks a significant reduction in glucose (∆ = − 0.30, 95% CI − 0.52, − 0.08; z = -2.64, p < 0.009) and insulin (∆ = − 0.54, 95% CI − 0.75, − 0.33; z = -4.98, p < 0.001) was observed. Both standing and light-intensity walking showed no effect on SBP.

Conclusions

Frequent short interruptions of standing significantly attenuated postprandial glucose compared to prolonged sitting; however, light-intensity walking was found to represent a superior physical activity break. The feasibility and longitudinal implications of breaking sedentary behaviour with light-intensity walking should be investigated in a free-living setting.

Registration

Not available.

Lipoprotein profiles of fat distribution and its association with insulin sensitivity

BACKGROUND

Fat deposition is associated with adverse outcomes. Waist-to-hip (WHR) ratio is a simple feasible index to assess fat distribution. Lipoprotein particle composition in relation to WHR and to what extent their association is mediated by insulin sensitivity are less investigated.

METHODS

In 504 randomly recruited Flemish (mean age: 48.9 years; women: 51.6%), we analyzed the lipoprotein particle constitutions using nuclear magnetic resonance spectroscopy. WHR obesity described a WHR of ≥ 0.85 for women or 0.9 for men. Insulin sensitivity was evaluated by the homeostasis model assessment-estimated insulin resistance (HOMA-IR). SCORE-2 risk algorithm was applied to estimate 10-year cardiovascular risk. Statistical methods included multivariable-adjusted linear regression analysis, logistic regression analysis, and mediation analysis.

RESULTS

The prevalence of WHR obesity was 54.6%, approximately 3 times of BMI-determined obesity (19.1%). Individuals with WHR obesity had significantly higher metabolic complications, such as hypertension (57.1%), dyslipidemia (61.8%), and insulin resistance (14.2%). WHR and WHR obesity were positively associated with total very-low-density lipoprotein (VLDL) particle concentration, remnant cholesterol, and triglycerides, but were negatively associated with VLDL particle size (P ≤ 0.027), independent of body mass index and other covariates. WHR was inversely associated with total high-density lipoprotein (HDL) particle concentration, whereas WHR obesity was inversely associated with HDL cholesterol (P ≤ 0.039). Neither WHR nor WHR obesity was associated with the concentration of total low-density lipoprotein (LDL) particles, LDL particle size, and LDL cholesterol (P ≥ 0.089). In the mediation analysis, insulin sensitivity significantly mediated the effect of WHR on total VLDL particle concentration (mediation percentage: 37.0%), remnant cholesterol (47.7%), and HDL cholesterol (41.1%). Individuals with WHR obesity were at increased cardiovascular risk, regardless of LDL cholesterol (P ≤0.028). In WHR obesity, higher total VLDL particle concent36ration and remnant cholesterol, and lower HDL cholesterol were associated with an increased cardiovascular risk (P≤ 0.002).

CONCLUSIONS

Upper-body fat deposition was independently associated with an unfavorable lipoprotein profile, and insulin sensitivity significantly mediated this association. LDL cholesterol might underestimate lipid abnormality for people with upper-body obesity and lowering VLDL particles and remnant cholesterol might potentially reduce the residual cardiovascular risk.

Insulin Resistance and Cardiometabolic Risk Profile Among Nondiabetic American Young Adults: Insights From NHANES

BACKGROUND

The burden of insulin resistance (IR) among young American adults has not been previously assessed. We evaluated (1) the prevalence and trends of IR and cardiometabolic risk factors and (2) the association between measures of adiposity and IR among adults 18 to 44 years of age without diabetes and preexisting cardiovascular disease.

METHODS

Cross-sectional survey data from six consecutive National Health and Nutrition Examination Survey (2007-2008 to 2017-2018) cycles were analyzed. IR was defined by the homeostatic model assessment for IR (HOMA-IR) of ≥2.5. The temporal trends of IR, cardiometabolic risk factors, and the relationship between IR and measures of adiposity were assessed using multivariable-adjusted regression models.

RESULTS

Among 6247 young adults 18 to 44 years of age, the prevalence of IR was 44.8% (95% CI: 42.0%-47.6%) in 2007-2010 and 40.3% (95% CI: 36.4%-44.2%) in 2015-2018 (P for trend = 0.07). There was a modest association of HOMA-IR with higher body mass index (BMI), waist circumference, total lean fat mass, and total and localized fat mass (all Ps < 0.001). Participants with IR had a higher prevalence of hypertension [31.3% (95% CI: 29.2%-33.5%) vs 14.7% (95% CI: 13.2%-16.2%)], hypercholesterolemia [16.0% (95% CI: 12.4%-19.5%) vs 7.0% (95% CI: 5.8%-8.5%)], obesity [56.6% (95% CI: 53.9%-59.3%) vs 14.7% (95% CI: 13.0%-16.5%)], and poor physical activity levels [18.3% (95% CI: 16.4%-20.2%) vs 11.7% (95%CI: 10.3-13.1%)] compared to participants without IR (all Ps < 0.05).

CONCLUSIONS

Four-in-10 young American adults have IR, which occurs in a cluster with cardiometabolic risk factors. Nearly half of young adults with IR are nonobese. Screening efforts for IR irrespective of BMI may be required.

Impact of insulin therapy before donation on graft outcomes in pancreas transplantation: An analysis of the OPTN/UNOS database

AIMS

Information on the impact of insulin therapy before pancreas donation on pancreas outcomes is scarce. We aim to explore the influence of insulin therapy before donation on recipient and pancreas graft survival.

METHODS

Registry study including 12,841 pancreas recipients from the OPTN/UNOS registry performed between 2000 and 2017. Inverse probability of treatment weighting (IPTW) was used to account for covariate imbalance between recipients from a donor with and without insulin requirements.

RESULTS

A total of 7765 (60%) patients received a pancreas from a donor with insulin before donation (IBD). Pancreas graft survival (death-censored) was similar between recipients from IBD and non-IBD donors at 1, 5 and 10 years (89% vs 89%, 78% vs 79 and 69% vs 70%, respectively, P = 0.35). Recipients from IBD donors presented a similar 90-days pancreas graft survival. After IPTW weighting, IBD donors were neither associated with any post-transplant surgical complication (HR 1.11 [95% CI 0.98-1.24], P = 0.06), nor with risk for recipient death (HR 0.94 [95% CI 0.85-1.04], P = 0.26), nor pancreas graft failure (HR 1.06 [95% CI 0.98-1.16], P = 0.15).

CONCLUSIONS

Insulin therapy before donation in accepted pancreas donors was not associated, per se, with an impaired pancreas graft and patient survival.

Is type 2 diabetes an adiposity-based metabolic disease? From the origin of insulin resistance to the concept of dysfunctional adipose tissue

In the last decades of the past century, a remarkable amount of research efforts, money and hopes was generated to unveil the basis of insulin resistance that was believed to be the primary etiological factor in the development of type 2 diabetes. From the Reaven's insulin resistance syndrome to the DeFronzo's triumvirate (skeletal muscle, liver and beta-cell) and to Kahn's discovery (among many others) of insulin receptor downregulation and autophosphorylation, an enthusiastic age of metabolic in vivo and in vitro research took place, making the promise of a resolutory ending. However, from many published data (those of insulin receptoropathies and lipodystrophies, the genome-wide association studies results, the data on reversibility of type 2 diabetes after bariatric surgery or very-low-calorie diets, and many others) it appears that insulin resistance is not a primary defect but it develops secondarily to increased fat mass. In particular, it develops from a mismatch between the surplus caloric intake and the storage capacity of adipose tissue. On this basis, we propose to change the today's definition of type 2 diabetes in adiposity-based diabetes.Level of Evidence as a narrative review a vast array of studies have been included in the analysis, ranging from properly designed randomized controlled trials to case studies; however, the overall conclusion may be regarded as level IV.

Insulin Resistance Is Associated with Multiple Chemical Sensitivity in a Danish Population-Based Study-DanFunD

Multiple chemical sensitivity (MCS) is a multisystem syndrome, and limited knowledge of its pathophysiology exists. Based on the population-based Danish cohort DanFunD, this study investigated metabolic health in people with MCS compared to individuals who did not have MCS. From 9656 cohort participants aged 18–76 years old, 1.95% were categorized as MCS individuals with comorbid functional somatic disorders (MCS +FSD, n = 188), and 1.13% were categorized as MCS without functional somatic disorders (MCS ÷FSD, n = 109). MCS was characterized based on three criteria: the experience of symptoms upon exposure to common odors and airborne chemicals, symptoms related the central nervous systems and others organ symptoms, and significant impact on every day, social, and occupational life. The remaining study population without MCS or any other functional somatic disorders were regarded as controls. We used adjusted multiple linear regression with link-function to evaluate the associations between lipid and glucose metabolism markers and MCS. We also tested the odds ratio of metabolic syndrome in MCS. Results did not point to statistically significant associations between lipid biomarkers or metabolic syndrome and both MCS groups compared to the controls. We found that MCS individuals may be more insulin resistant and that MCS ÷ FSD may have an impaired glucose metabolism when compared to controls.

Comparison of methods to identify individuals with obesity at increased risk of functional impairment among a population of home-dwelling older adults

Obesity is associated with increased muscle mass and muscle strength. Methods taking into account the total body mass to reveal obese older individuals at increased risk of functional impairment are needed. Therefore, we aimed to detect methods to identify obese older adults at increased risk of functional impairment. Home-dwelling older adults (n 417, ≥ 70 years of age) were included in this cross-sectional study. Sex-specific cut-off points for two obesity phenotypes (waist circumference (WC) and body fat mass (FM %)) were used to divide women and men into obese and non-obese groups, and within-sex comparisons were performed. Obese women and men, classified by both phenotypes, had similar absolute handgrip strength (HGS) but lower relative HGS (HGS/total body mass) (P < 0·001) than non-obese women and men, respectively. Women with increased WC and FM %, and men with increased WC had higher appendicular skeletal muscle mass (P < 0·001), lower muscle quality (HGS/upper appendicular muscle mass) (P < 0·001), and spent longer time on the stair climb test and the repeated sit-to-stand test (P < 0·05) than non-obese women and men, respectively. Absolute muscle strength was not able to discriminate between obese and non-obese older adults. However, relative muscle strength in particular, but also muscle quality and physical performance tests, where the total body mass was taken into account or served as an extra load, identified obese older adults at increased risk of functional impairment. Prospective studies are needed to determine clinically relevant cut-off points for relative HGS in particular.

Cardiometabolic Modification of Amyloid Beta in Alzheimer's Disease Pathology

In recent years, several studies have suggested that cardiometabolic disorders, such as diabetes, obesity, hypertension, and dyslipidemia, share strong connections with the onset of neurodegenerative disorders such as Parkinson's and Alzheimer's disease (AD). However, establishing a definitive link between medical disorders with coincident pathophysiologies is difficult due to etiological heterogeneity and underlying comorbidities. For this reason, amyloid β (Aβ), a physiological peptide derived from the sequential proteolysis of amyloid precursor protein (APP), serves as a crucial link that bridges the gap between cardiometabolic and neurodegenerative disorders. Aβ normally regulates neuronal synaptic function and repair; however, the intracellular accumulation of Aβ within the brain has been observed to play a critical role in AD pathology. A portion of Aβ is believed to originate from the brain itself and can readily cross the blood-brain barrier, while the rest resides in peripheral tissues that express APP required for Aβ generation such as the liver, pancreas, kidney, spleen, skin, and lungs. Consequently, numerous organs contribute to the body pool of total circulating Aβ, which can accumulate in the brain and facilitate neurodegeneration. Although the accumulation of Aβ corresponds with the onset of neurodegenerative disorders, the direct function of periphery born Aβ in AD pathophysiology is currently unknown. This review will highlight the contributions of individual cardiometabolic diseases including cardiovascular disease (CVD), type 2 diabetes (T2D), obesity, and non-alcoholic fatty liver disease (NAFLD) in elevating concentrations of circulating Aβ within the brain, as well as discuss the comorbid association of Aβ with AD pathology.

Dynapenic abdominal obesity in hospitalized elderly patients with acute myocardial infarction

Obesity and dynapenia are cardiovascular risk factors. When present together, it is called dynapenic abdominal obesity and can potentiate adverse outcomes. This study aims to estimate the prevalence of dynapenic abdominal obesity and its relationship with prognostic markers in patients with acute myocardial infarction (AMI). This is a hybrid study with a longitudinal component plus a cross-sectional component at baseline involving elderly patients admitted to a reference hospital in cardiology due to AMI in the Brazilian Northeast from May to October 2015. We analyzed patients' admission data and evaluated some prognostic markers up to two years after admission. We established abdominal obesity by measuring waist circumference (>102 cm for men and >88 cm for women) and dynapenia by handgrip strength (<27 kg/F for men and <16 kg/F for women). We considered the prognostic markers troponin and creatinine kinase - MB (CKMB), AMI classification according to ST segment elevation, TIMI score, need for coronary angioplasty or coronary artery bypass surgery, complications during hospitalization and within two years after admission, and re-admission to the same service. We evaluated 92 patients with a mean age of 71.4 ± 7.5 years. The prevalence of abdominal obesity and dynapenia was 56.5% and 44.6%, respectively. The coexistence of the two conditions occurred in 25.0% of the patients, being higher among women (p < 0.001). When comparing the dynapenic abdominal obese groups with the group of patients who had one of the two isolated conditions we observed that, for a same mean age and clinical characteristics, patients with only one of the conditions had a higher CKMB (p = 0.046) and troponin median (p = 0.032). The presence of dynapenia in the groups of abdominal obese and non-abdominal obese individuals is not associated with risk marker parameters (p > 0.05). High prevalence of abdominal obesity and dynapenia occurred among patients with AMI and in a quarter of these both conditions coexisted. Dynapenic abdominal obesitydoes not increase the risk of adverse outcomes and isolated dynapenia is not a marker of a poor prognosis.

Resistance Band Exercise Training Prevents the Progression of Metabolic Syndrome in Obese Postmenopausal Women

Metabolic syndrome (MetS) is classified as a combination of risk factors for cardiovascular disease (CVD), and postmenopausal women are specifically at an increased risk for MetS, in part due to the hormonal and metabolic changes that occur at the menopause transition. It is crucial to combat the components of MetS with appropriate lifestyle interventions in this population, such as exercise. This study aimed to examine the effects of a resistance band exercise training program in obese postmenopausal women with MetS. A total 35 postmenopausal women were randomly assigned to either a control group (CON, n = 17) or a resistance band exercise training group (EX, n = 18). Participants in the EX group trained 3days/week. Levels of blood glucose, insulin, homeostatic model of insulin resistance (HOMA-IR), blood lipid profile, anthropometrics, and blood pressure (BP) were measured at baseline and after the exercise intervention. There were significant group by time interactions (p < 0.05) for blood glucose (Δ-4.5 mg/dl), insulin (Δ -1.3 μU/ml), HOMA-IR (Δ -0.6), triglycerides (Δ -9.4 mg/dl), low-density lipoprotein cholesterol(Δ -10.8 mg/dl), systolic BP(Δ -3.4 mmHg), body fat percentage (Δ -3.0 %), and waist circumference (Δ -3.4 cm), which significantly decreased (p < 0.05), and lean body mass (Δ 0.7 kg) and high-density lipoprotein cholesterol (Δ 5.1 mg/dl), which significantly increased (p < 0.05) after EX compared to no change in CON. The present study indicates that resistance band exercise training may be an effective therapeutic intervention to combat the components of MetS in this population, potentially reducing the risk for the development of CVD.

Cardio-metabolic outcomes in South Asians compared to White Europeans in the United Kingdom: a matched controlled population-based cohort study

BACKGROUND

There appears to be an inequality in the risk of cardio-metabolic disease between those from a South Asian (SA) background when compared to those of White Europeans (WE) descendance, however, this association has not been explored in a large European cohort. This population-based open retrospective cohort explores the incidence of cardio-metabolic disease in those without pre-existing cardiometabolic disease taken from a large UK primary care database from 1st January 2007 to 31st December 2017.

METHODS

A retrospective open cohort matched population-based study using The Health Improvement Network (THIN) database. The outcomes of this study were the incidences of cardio-metabolic events (type 2 diabetes mellitus, hypertension, ischemic heart disease, stroke, heart failure, and atrial fibrillation).

RESULTS

A total of 94,870 SA patients were matched with 189,740 WE patients. SA were at an increased risk of developing: T2DM (adjusted hazard ratio (aHR) 3.1; 95% CI 2.97-3.23); HTN (1.34; 95% CI: 1.29-1.39); ischaemic heart disease (IHD) (1.81; 95% CI: 1.68-1.93) and heart failure (HF) (1.11; 95% CI: 1.003-1.24). However, they were at a lower risk of atrial fibrillation (AF) (0.53; 95% CI: 0.48-0.59) when compared to WE. Of those of SA origin, the Bangladeshi community were at the greatest risk of T2DM, HTN, IHD and HF, but were at the lowest risk of AF in when compared to Indians and Pakistanis.

CONCLUSION

Considering the high risk of cardio-metabolic diseases in the SA cohort, differential public health measures should be considered in these patients to reduce their risk of disease, which may be furthered tailored depending on their country of origin.

The Association of Upper Body Obesity with Insulin Resistance in the Newfoundland Population

Body-fat distribution is a primary risk factor for insulin resistance and cardiovascular disease. Visceral fat explains only a portion of this risk. The link between upper-body fat and insulin resistance is uncertain. Furthermore, upper-body fat is not clearly defined. Dual-energy X-ray absorptiometry (DXA) can accurately quantify body fat. In this study, we explored the relationship between non-visceral upper-body adiposity and insulin resistance and other markers of metabolic syndrome. Fat proportions in the upper body, leg, and visceral regions were quantified by using DXA in 2547 adult Newfoundlanders aged 19 and older. Adjusting for remaining fat regions, we performed partial correlation analysis for each body region and insulin resistance defined by the Homeostatic Model of Assessment (HOMA). Similarly, partial correlation analysis was also performed between each fat region and other markers of metabolic syndrome, including high-density lipoprotein cholesterol (HDL), triglycerides (TG), body mass index (BMI), and blood pressure. Major confounding factors, including age, caloric intake, and physical activity, were statistically controlled by using partial correlation analysis. Interactions between sex, menopausal status, and medication status were also tested. Arm adiposity was correlated with HOMA-IR (R = 0.132, p < 0.001) and HOMA-β (R = 0.134, p < 0.001). Visceral adiposity was correlated with HOMA-IR (R = 0.230, p < 0.001) and HOMA-β (R = 0.160, p < 0.001). No significant correlation between non-visceral trunk adiposity and insulin resistance was found. Non-visceral trunk adiposity was negatively correlated with HDL in men (R = −0.110, p < 0.001) and women (R = −0.117, p < 0.001). Non-visceral trunk adiposity was correlated with TG (total: R = 0.079, p < 0.001; men: R = 0.105, p = 0.012; women: R = 0.078, p = 0.001). In menopausal women, leg adiposity was negatively correlated with HOMA-IR (R = −0.196, p < 0.001) and HOMA-β (R = −0.101, p = 0.012). Upper-body adiposity in the arms is an independent contributor to insulin resistance. Upper-body adiposity in the non-visceral trunk region is an independent contributor to metabolic syndrome. Leg adiposity is protective against metabolic syndrome in women.

Comparison of Indices of Carbohydrate Quality and Food Sources of Dietary Fiber on Longitudinal Changes in Waist Circumference in the Framingham Offspring Cohort

The long-term impact of carbohydrate quality on abdominal weight gain is not fully understood. We aimed to examine the prospective relation of a carbohydrate quality index (CQI; defined by four criteria: dietary fiber, glycemic index, whole grain-to-total grain ratio, and solid-to-total carbohydrate ratio), total, cereal grain, vegetable, and fruit fiber, carbohydrate-to-total fiber ratio, and carbohydrate-to-cereal fiber ratio with changes in waist circumference (WC). Subjects were middle-aged to older, mostly white, participants in the Framingham Offspring cohort (n = 3101 subjects), with mean baseline age 54.9 ± 0.2 years (mean ± SE) and body mass index (BMI) 27.2 ± 0.1 kg/m². Food frequency questionnaire (FFQ), health, and lifestyle data were collected approximately every four years over a median total follow-up of 18 years. Repeated measure mixed models were used to estimate adjusted mean change in WC per four-year interval across quartiles of carbohydrate variables. In the most adjusted model, a higher CQI was marginally associated with a smaller increase in WC (2.0 ± 0.1 vs. 2.4 ± 0.1 cm in highest vs. lowest quartile, p-trend = 0.04). Higher ratios of carbohydrate-to-fiber and carbohydrate-to-cereal fiber were associated with greater increases in WC per four-year interval (2.6 ± 0.1 vs. 2.0 ± 0.1 cm, p-trend < 0.001, and 2.5 ± 0.1 vs. 2.1 ± 0.1 cm in highest versus lowest categories, p-trend = 0.007, respectively); whereas higher intake of total fiber (1.8 ± 0.1 vs. 2.7 ± 0.1 cm, p-trend < 0.001), cereal fiber (2.0 ± 0.1 vs. 2.5 ± 0.1 cm, p-trend = 0.001), and fruit fiber (2.0 ± 0.1 vs. 2.7 ± 0.1 cm, p-trend < 0.001) were associated with smaller increases in WC compared to lower intakes. There was a significant interaction between total fiber and total carbohydrate (as % of total energy intake). After stratification, the association between fiber intake and change in WC was not maintained in the context of a high carbohydrate diet. Better carbohydrate quality, primarily higher fiber intake and lower carbohydrate-to-fiber ratios, may help attenuate increases in abdominal adiposity over time.

End-stage kidney disease in patients with clinically manifest vascular disease; incidence and risk factors: results from the UCC-SMART cohort study

BACKGROUND

Patients with cardiovascular disease (CVD) are at increased risk of end-stage kidney disease (ESKD). Insights into the incidence and role of modifiable risk factors for end-stage kidney disease may provide means for prevention in patients with cardiovascular disease.

METHODS

We included 8402 patients with stable cardiovascular disease. Incidence rates (IRs) for end-stage kidney disease were determined stratified according to vascular disease location. Cox proportional hazard models were used to assess the risk of end-stage kidney disease for the different determinants.

RESULTS

Sixty-five events were observed with a median follow-up of 8.6 years. The overall incidence rate of end-stage kidney disease was 0.9/1000 person-years. Patients with polyvascular disease had the highest incidence rate (1.8/1000 person-years). Smoking (Hazard ratio (HR) 1.87; 95% CI 1.10-3.19), type 2 diabetes (HR 1.81; 95% CI 1.05-3.14), higher systolic blood pressure (HR 1.37; 95% CI 1.24-1.52/10 mmHg), lower estimated glomerular filtration rate (eGFR) (HR 2.86; 95% CI 2.44-3.23/10 mL/min/1.73 m²) and higher urine albumin/creatinine ratio (uACR) (HR 1.19; 95% CI 1.15-1.23/10 mg/mmol) were independently associated with elevated risk of end-stage kidney disease. Body mass index (BMI), waist circumference, non-HDL-cholesterol and exercise were not independently associated with risk of end-stage kidney disease.

CONCLUSIONS

Incidence of end-stage kidney disease in patients with cardiovascular disease varies according to vascular disease location. Several modifiable risk factors for end-stage kidney disease were identified in patients with cardiovascular disease. These findings highlight the potential of risk factor management in patients with manifest cardiovascular disease.

Dynapenia in middle-aged and older persons with and without abdominal obesity and the complex relationship with behavioral, physical-health and mental-health variables: Learning Bayesian network structures

BACKGROUND

Few studies have analyzed the relationship between dynapenia and lifestyle, physical-health and mental-health variables in middle-aged and older persons classified according to their waist circumference. The aim of this study was to identify the relationships between dynapenia and behavioral, physical-health and mental-health variables in middle-aged and older persons with and without abdominal obesity using Bayesian networks, a graphical analysis technique that allows simultaneous associations between variables to be identified.

METHODS

A cross-sectional study of 2526 participants without abdominal obesity and 2729 with abdominal obesity (waist circumference > 102 cm in men and >88 cm in women) aged 50 years or older who took part in the Brazilian Longitudinal Study of Aging. Two network structures including behavioral, physical-health and mental-health variables and dynapenia (grip strength < 26 kg for men and <16 kg for women) were learnt with the hill-climbing score-based algorithm for a sample of individuals with and without abdominal obesity. Statistical resampling tests were performed to quantify the strength of the relationships between factors associated with dynapenia.

RESULTS

In middle-aged and older persons without abdominal obesity, dynapenia was strongly associated with and influenced by at-risk alcohol consumption while in middle-aged and older persons with abdominal obesity the condition was strongly associated with and influenced by diabetes and depression. In the latter group, dynapenia was also strongly associated with and influenced the disability.

CONCLUSIONS

The use of Bayesian networks allowed different factors associated with dynapenia in middle-aged and older persons classified according to the presence or absence of abdominal obesity to be identified.

Visceral fat and cardiorespiratory fitness with prevalence of pre-diabetes/diabetes mellitus among middle-aged and elderly Japanese people: WASEDA'S Health Study

The relationships between cardiorespiratory fitness (CRF) measurements not confounded by adiposity and the prevalence of pre-diabetes mellitus (pre-DM) and diabetes mellitus (DM) are not well known. Thus, we aimed to investigate the associations of visceral fat (VF) and CRF with the prevalence of pre-DM/DM among Japanese adults. The study included 970 individuals (327 women and 643 men) who were 40-87 years old and had complete health examinations, abdominal fat area, and fitness data from WASEDA'S Health Study during 2015-2018. The VF area was measured using magnetic resonance imaging. CRF was measured using a cycle ergometer and was defined as VO2peak divided by fat free mass. The pre-DM/DM was identified based on the questionnaire and fasting blood tests. The odds ratios (ORs) and 95% confidence intervals (CIs) for prevalence of pre-DM/DM were calculated. Seventy-three participants had pre-DM and 48 participants had DM. Compared to the low VF group, the high VF group had a higher prevalence of pre-DM/DM (OR: 1.87, 95% CI: 1.18-2.96), although no significant relationship was observed between CRF and pre-DM/DM prevalence (P for trend = 0.239). The sub-group analyses also revealed no significant relationship between CRF and pre-DM/DM prevalence in the low VF group (P for trend = 0.979), although CRF values were inversely related to the prevalence of pre-DM/DM in the high VF group (P for trend = 0.024). Although CRF was not independently related to the prevalence of pre-DM/DM after adjusting for adiposity, higher VF values were related to a higher prevalence of pre-DM/DM. In addition, CRF levels were inversely associated with the prevalence of pre-DM/DM only among high VF individuals.

Young, healthy males and females present cardiometabolic protection against the detrimental effects of a 7-day high-fat high-calorie diet

PURPOSE

High-fat, high-calorie (HFHC) diets have been used as a model to investigate lipid-induced insulin resistance. Short-term HFHC diets reduce insulin sensitivity in young healthy males, but to date, no study has directly compared males and females to elucidate sex-specific differences in the effects of a HFHC diet on functional metabolic and cardiovascular outcomes.

METHODS

Eleven males (24 ± 4 years; BMI 23 ± 2 kg.m^-2; V̇O_{2 peak} 62.3 ± 8.7 ml.min^-1.kg^-1FFM) were matched to 10 females (25 ± 4 years; BMI 23 ± 2 kg.m^-2; V̇O_{2 peak} 58.2 ± 8.2 ml.min^-1.kg^-1FFM). Insulin sensitivity, measured via oral glucose tolerance test, metabolic flexibility, arterial stiffness, body composition and blood lipids and liver enzymes were measured before and after 7 days of a high-fat (65% energy) high-calorie (+ 50% kcal) diet.

RESULTS

The HFHC diet did not change measures of insulin sensitivity, metabolic flexibility or arterial stiffness in either sex. There was a trend towards increased total body fat mass (kg) after the HFHC diet (+ 1.8% and + 2.3% for males and females, respectively; P = 0.056). In contrast to females, males had a significant increase in trunk to leg fat mass ratio (+ 5.1%; P = 0.005).

CONCLUSION

Lean, healthy young males and females appear to be protected from the negative cardio-metabolic effects of a 7-day HFHC diet. Future research should use a prolonged positive energy balance achieved via increased energy intake and reduced energy expenditure to exacerbate negative metabolic and cardiovascular functional outcomes to determine whether sex-specific differences exist under more metabolically challenging conditions.

Evaluation of risk factors for insulin resistance: a cross sectional study among employees at a private university in Lebanon

BACKGROUND

Worldwide, the prevalence of insulin resistance ranges from 15.5 to 46.5%, among adults. Lebanon reported one of the highest rates reaching 44.6%. The literature suggests an association between dairy product consumption and insulin resistance, however results are inconclusive. To our knowledge, no study examined this association in the Middle Eastern Region. The aim of the study was to investigate the prevalence of insulin resistance among a sample of Lebanese adults, to identify its risk factors depending on gender, and to evaluate the association between insulin resistance and dairy products consumption.

METHODS

A cross-sectional study was conducted among employees at Notre Dame University - Louaize. Four questionnaires were administered including a background and International Physical Activity Questionnaire short form questionnaires, food frequency questionnaire and a 24 h recall. Bioelectric Impedance Analysis (BIA) was used to measure percent body fat (PBF). Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) was used to quantify insulin resistance. A person with HOMA-IR ≥ 2.5 was considered as insulin resistant. Statistical analyses were performed using the Statistical Package for Social Sciences version 23 for Windows. P < 0.05 was considered statistically significant.

RESULTS

Out of 286 study participants, 38.0% were insulin resistant. Average dairy product intake in the total sample was 2.2 ± 1.0 servings per day. Among males, the odds of having insulin resistance were 3.9 times higher (95%CI 1.4-11.0; p = 0.009) for those having a risky waist circumference compared to those having a healthy waist circumference. Among females, being married (OR: 0.2, 95%CI 0.1-0.5; p = 0.002), PBF (OR: 1.2, 95%CI 1.0-1.3; p = 0.008) and hypertriglyceridemia (OR: 8.7, 95%CI: 2.1-35.9; p = 0.003) were associated with HOMA-IR, after controlling for confounders. Dairy intake was not associated with HOMA-IR neither among males (p = 0.777), nor among females (p = 0.968), after controlling for confounders.

CONCLUSION

Dairy consumption was not associated with increased insulin resistance. More research focusing on the relationship between dairy intake and insulin resistance is needed, especially in the Arab and Middle-Eastern region. Future studies should examine the effect of different types of dairy products and the effect of different nutrients in dairy products on insulin resistance.

Does Abdominal Obesity Accelerate Muscle Strength Decline in Older Adults? Evidence From the English Longitudinal Study of Ageing

Background

Cross-sectional evidence has shown an association between abdominal obesity and lower muscle strength in older adults. However, no longitudinal findings have confirmed this association. In addition, the impact of abdominal fat on the reduction in muscle strength is not yet fully understood.

Methods

We investigated the longitudinal associations between abdominal obesity and handgrip strength in 5,181 older adults from the English Longitudinal Study of Ageing over 8 years of follow-up. Muscular strength was measured using a manual dynamometer. Abdominal obesity was defined as a waist circumference >102 cm for men and >88 cm for women. Generalized linear mixed models were adjusted by measures of socioeconomic status, health conditions, lifestyle, cognition, depressive symptoms, biomarkers, and disability.

Results

At baseline, the mean age of participants was 65.8 years and their mean waist circumference and body mass index (BMI) were 95 cm and 27.7 kg/m², respectively. Fully adjusted models showed that abdominal obese men and women had stronger muscle strength at baseline. The decline over time in muscle strength was accelerated in abdominal obese men (−0.12 kg/year, 95% confidence interval: −0.24 to −0.01) compared with nonabdominal obese. This association was not found in women. Comparative analyses showed that overweight men according to their BMI were not at greater risk of muscle strength decline. However, these men were at risk based on their waist circumference.

Conclusions

Abdominal obesity is associated with accelerated muscle strength decline in men.

Influence of Nutritional Education on the Diet and Nutritional Behaviors of Elderly Women at the University of the Third Age

Background: The objective of this study was to evaluate the diet composition, body fat content, and physical activity (PA), considering blood lipid levels and insulin resistance markers, in elderly women who were well educated in nutrition and healthy lifestyle choices. Methods: A total of 106 postmenopausal women took part in the study. The study group included 62 students from the University of the Third Age (U3A); the control group (CG) included 44 females from the Silesia region. We evaluated their daily macro and micronutrient intake, levels of PA, percent of body fat (PBF), and the visceral fatty area (VFA). We also evaluated the lipid profile, insulin and glucose levels, homeostatic model assessment of insulin resistance (HOMA-_IR), and C-reactive protein (CRP) levels. Results: Significant differences were observed in carbohydrate, protein, fiber, as well as vitamins and minerals consumption between the U3A group and the CG. There were no differences in the PBF and VFA between the groups. Furthermore, no differences were shown in the measured blood variables. The U3A group walked more than 11,000 steps a day and performed 46.15 min/day of PA with a moderate intensity of 3–6 metabolic equivalents of task (METs, min/week). Conclusions: Despite the fact that the U3A group were physically active females, well educated on healthy, balanced diets and had the motivation to learn about proper nutritional behaviors, they did not follow these recommendations in everyday life.

The Effect of a Low GI Diet on Truncal Fat Mass and Glycated Hemoglobin in South Indians with Type 2 Diabetes-A Single Centre Randomized Prospective Study

Background: There has been no previous study that has investigated the effect of a low glycemic index (LGI) diet with local recipes of South Indian cuisine on the body fat composition using dual-energy X-ray absorptiometry (DXA). Truncal obesity has been associated with the risk of metabolic disorders and cardiovascular diseases. Aim: The aim of this study was to examine the effect of a low GI diet on glycemic control and body composition in people with type 2 diabetes in South India. Method: This was a prospective and randomized controlled study that was conducted over a period of 24 weeks. A total of 40 participants were recruited from the Department of Endocrinology and Diabetes Outpatient in Kerala, South India. All the patients had type 2 diabetes and were randomly assigned and given advice and instructions to follow either a low GI diet plan (n = 18) or their usual diet, which served as control (n = 18). The advice was reinforced throughout the study period. Dietary compliance was evaluated based on a 24 h dietary recall at weeks 3, 11, 12, 18, 23, and 24. The age of the subjects ranged from 35 to 65 years. Anthropometric, body composition, and cardio-metabolic parameters were measured according to standard procedures. T-tests were conducted to compare differences between intervention and control groups and the Pearson correlation coefficient was used to evaluate associations between the variables. Results: There were significant reductions (p < 0.05) in the low GI diet compared to the control group with respect to weight, body mass index (BMI), and triceps skinfold thickness. Similarly, significant reductions were observed in the low GI diet group with respect to region, total fat, android, and gynoid fat mass and the differences between the groups were significant at p < 0.05. There was also a positive correlation between BMI and android fat mass (r = 0.745), total fat mass (r = 0.661), total truncal mass (r = 0.821), and truncal fat (r = 0.707). There was a significant reduction in glycated hemoglobin in the low GI diet group compared to the control group at p < 0.05. Conclusion: This study has demonstrated that there was a significant reduction (p < 0.05) of truncal obesity and glycated hemoglobin in patients with type 2 diabetes on a local diet of South Indian cuisine with low GI compared with the control.

The Effects of Dairy Intake on Insulin Resistance: A Systematic Review and Meta-Analysis of Randomized Clinical Trials

The incidence of type 2 diabetes mellitus (DM) has increased in the US over the last several years. The consumption of low-fat dairy foods has been linked with decreasing the risk of DM but studies have yet to show a clear correlation. We conducted a systematic review and meta-analysis of randomized clinical trials (RCTs) evaluating the effects of dairy intake on homeostatic model assessment of insulin resistance (HOMA-IR), waist circumference, and body weight. In MEDLINE and Embase, we identified and reviewed 49 relevant RCTs: 30 had appropriate data format for inclusion in the meta-analysis. Using the Review Manager 5 software, we calculated the pooled standardized mean differences comparing dairy dietary interventions to control for our outcomes of interest. For HOMA-IR (794 individuals), we found a mean difference of −1.21 (95% CI −1.74 to −0.67; p-value < 0.00001; I² = 92%). For waist circumference (1348 individuals), the mean difference was −1.09 cm (95% CI 1.68 to −0.58; p-value < 0.00001; I² = 94%). For body weight (2362 individuals), the dairy intake intervention group weighed 0.42 kg less than control (p-value < 0.00001; I² = 92%). Our findings suggest that dairy intake, especially low-fat dairy products, has a beneficial effect on HOMA-IR, waist circumference, and body weight. This could impact dietary recommendations to reduce DM risk.

Central adiposity in relation to risk of liver cancer in Chinese adults: A prospective study of 0.5 million people

Central adiposity is associated with liver cancer risk beyond general adiposity in Western populations. However, there is little prospective evidence in East Asian populations who are more likely to have central adiposity at given BMI levels. The prospective China Kadoorie Biobank recruited 512,713 adults aged 30-79 years from 10 diverse areas. During 10 years follow-up, 2,847 incident cases of liver cancer were identified. Cox regression was used to estimate adjusted hazard ratios (HR) for liver cancer associated with central adiposity, excluding individuals with cancers and liver diseases at baseline and the first 5 years of follow-up (1,049 incident liver cancer cases). Overall, mean waist circumference (WC) was 82.2 (SD 9.8) cm in men and 79.1 (9.5) cm in women. Central adiposity showed positive associations with liver cancer risk. Associations were strongest for WC and waist-to-hip ratio (WHR), with adjusted HRs per 1-SD of 1.09 (95%CI 1.01-1.18) and 1.12 (1.02-1.23), respectively. The positive associations became stronger when additionally adjusting for BMI (1.26 [1.09-1.46] and 1.14 [1.02-1.28]). The positive association of central obesity (WC ≥90 cm in men and ≥ 80 cm in women) with liver cancer increased progressively with the number of other presenting metabolic risk factors (physical inactivity, diabetes, and hypertension), with HRs of 1.07 (0.90-1.28), 1.17 (1.00-1.38), and 1.91 (1.40-2.59) in those with one, two, and three factors (p for trend 0.006). In this relatively lean Chinese population, there were positive associations of central adiposity with risk of liver cancer, with WHR and WC showing the strongest associations.

Correlates of Insulin-Stimulated Glucose Disposal in Recent-Onset Type 1 and Type 2 Diabetes

CONTEXT AND OBJECTIVE

Not only type 2 diabetes (T2D), but also type 1 diabetes (T1D), can be associated with insulin resistance, as assessed using insulin-stimulated whole-body glucose disposal (M-value). We hypothesized that different factors would affect the M-value at the onset of T1D and T2D.

DESIGN AND PATIENTS

We examined 132 patients with T1D or T2D matched for sex, age, and body mass index with a known diabetes duration of <12 months. Multivariable linear regression analyses were applied to test the associations between glycemic control, blood lipid levels, adiponectin, and proinflammatory immune mediators and the M-value, obtained from the hyperinsulinemic-euglycemic clamp.

RESULTS

Despite comparable age, body mass index, and near-normoglycemic control, the mean M-value was lower in those with T2D than in those with T1D. Patients with T1D had a lower waist/hip ratio and serum triglycerides but higher serum adiponectin than patients with T2D. However, the circulating proinflammatory markers were not different. Even with adjustments for glucose-lowering treatments, the fasting blood glucose correlated negatively with the M-value in both groups. However, gamma-glutamyl transferase-independently of any treatments-correlated negatively only in T2D. In contrast, serum adiponectin correlated positively with the M-values.

CONCLUSIONS

Fasting glycemia correlated with insulin-stimulated glucose disposal in both diabetes types. However, altered liver and adipose tissue function were associated with insulin-stimulated glucose disposal only in T2D, underpinning the specific differences between these diabetes types.

Leucine Supplementation Does Not Alter Insulin Sensitivity in Prefrail and Frail Older Women following a Resistance Training Protocol

BACKGROUND

Frailty is a clinical condition associated with loss of muscle mass and strength (sarcopenia). Although sarcopenia has multifactorial causes, it might be partly attributed to a blunted response to anabolic stimuli. Leucine acutely increases muscle protein synthesis, and resistance training (RT) is the strongest stimuli to counteract sarcopenia and was recently shown to improve insulin sensitivity (IS) in frail older women. Discrepancies exist regarding whether chronic supplementation of leucine in conjunction with RT can improve muscle mass and IS.

OBJECTIVE

The aim of this double-blinded placebo-controlled study was to determine the effects of leucine supplementation and RT on IS in prefrail and frail older women.

METHODS

Using the Fried criteria, 19 nondiabetic prefrail (1-2 criteria) and frail (≥3 criteria) older women (77.5 ± 1.3 y; body mass index (kg/m2): 25.1 ± 0.9) underwent a 3-mo intervention of RT 3 times/wk with protein-optimized diet of 1.2 g·kg-1·d-1 and 7.5 g·d-1 of l-leucine supplementation compared with placebo l-alanine. Pre-/postintervention primary outcomes were fasting plasma glucose, serum insulin, and 4-h responses to a standard meal of complete liquid formula. Secondary outcomes of resting energy expenditure using indirect calorimetry and body composition using dual-energy X-ray absorptiometry were obtained. Paired t tests analyzed pooled data, and 2-factor repeated-measures ANOVA determined supplementation, training, and interaction effects.

RESULTS

No significant time, group, or interaction effects were observed for postprandial areas under the curve of serum insulin or plasma glucose or for resting energy expenditure in l-leucine compared with l-alanine. Total lean body mass increased and percentage body fat decreased significantly for both groups postintervention (0.76 ± 0.13 and -0.92 ± 0.33 kg, respectively; time effect: P < 0.01).

CONCLUSIONS

IS was not affected by RT and leucine supplementation in nondiabetic prefrail and frail older women. Therefore, leucine supplementation does not appear to influence IS under these conditions. This trial was registered at clinicaltrials.gov as NCT01922167.

The role of dihydrosphingolipids in disease

Dihydrosphingolipids refer to sphingolipids early in the biosynthetic pathway that do not contain a C4-trans-double bond in the sphingoid backbone: 3-ketosphinganine (3-ketoSph), dihydrosphingosine (dhSph), dihydrosphingosine-1-phosphate (dhS1P) and dihydroceramide (dhCer). Recent advances in research related to sphingolipid biochemistry have shed light on the importance of sphingolipids in terms of cellular signalling in health and disease. However, dihydrosphingolipids have received less attention and research is lacking especially in terms of their molecular mechanisms of action. This is despite studies implicating them in the pathophysiology of disease, for example dhCer in predicting type 2 diabetes in obese individuals, dhS1P in cardiovascular diseases and dhSph in hepato-renal toxicity. This review gives a comprehensive summary of research in the last 10-15 years on the dihydrosphingolipids, 3-ketoSph, dhSph, dhS1P and dhCer, and their relevant roles in different diseases. It also highlights gaps in research that could be of future interest.

Could Age, Sex and Physical Fitness Affect Blood Glucose Responses to Exercise in Type 1 Diabetes?

Closed-loop systems for patients with type 1 diabetes are progressing rapidly. Despite these advances, current systems may struggle in dealing with the acute stress of exercise. Algorithms to predict exercise-induced blood glucose changes in current systems are mostly derived from data involving relatively young, fit males. Little is known about the magnitude of confounding variables such as sex, age, and fitness level-underlying, uncontrollable factors that might influence blood glucose control during exercise. Sex-related differences in hormonal responses to physical exercise exist in studies involving individuals without diabetes, and result in altered fuel metabolism during exercise. Increasing age is associated with attenuated catecholamine responses and lower carbohydrate oxidation during activity. Furthermore, higher fitness levels can alter hormonal and fuel selection responses to exercise. Compounding the limited research on these factors in the metabolic response to exercise in type 1 diabetes is a limited understanding of how these variables affect blood glucose levels during different types, timing and intensities of activity in individuals with type 1 diabetes (T1D). Thus, there is currently insufficient information to model a closed-loop system that can predict them accurately and consistently prevent hypoglycemia. Further, studies involving both sexes, along with a range of ages and fitness levels, are needed to create a closed-loop system that will be more precise in regulating blood glucose during exercise in a wide variety of individuals with T1D.

Combined Association of Cardiorespiratory Fitness and Body Fatness With Cardiometabolic Risk Factors in Older Norwegian Adults: The Generation 100 Study

Objective

To investigate the independent and combined associations of fitness and fatness with cardiometabolic risk factors in older Norwegian women and men.

Patients and Methods

We conducted a cross-sectional study of 505 women and 417 men aged 70 to 77 years enrolled in the Generation 100 study in Norway. Fitness was assessed as peak oxygen uptake and fatness as high body mass index (BMI; ≥25 kg/m²), waist circumference (WC) of 88 cm or greater for women and 102 cm or greater for men, and percent body fat (%BF) of 35% or greater and 25% or greater for women and men, respectively. High cardiometabolic risk was defined as the presence of 2 or more of the following risk factors: elevated triglyceride level, reduced high-density lipoprotein cholesterol concentration, elevated blood pressure, and elevated fasting glucose level or pharmacological treatment of these conditions.

Results

Receiver operating characteristic curve analyses identified fitness levels of less than 25.7 and less than 30.7 mL/kg per minute in women and men, respectively, as critical thresholds for having high cardiometabolic risk. Individuals with levels below these thresholds had an adjusted odds ratio of 2.77 (95% CI, 2.09-3.66) for having high cardiometabolic risk, while high BMI, WC, and %BF had odds ratios (95% CIs) of 3.58 (2.69-4.77), 3.06 (2.29-4.10), and 3.26 (2.47-4.30), respectively. In our combined analyses, being lean did not attenuate the cardiometabolic risk associated with low fitness, and combinations of low fitness and/or high BMI, WC, or %BF cumulatively increased cardiometabolic risk.

Conclusion

Low fitness and indication of fatness were independently and cumulatively associated with poor cardiometabolic health. Our results emphasize the importance of including both physical fitness and body fatness in the assessment of cardiometabolic risk and health promotion efforts in older adults.

Animal-Protein Intake Is Associated with Insulin Resistance in Adventist Health Study 2 (AHS-2) Calibration Substudy Participants: A Cross-Sectional Analysis

Background: High intakes of total and animal protein are associated with the risk of type 2 diabetes (T2D). The influence of protein type on insulin resistance, a key precursor of T2D, has not been extensively studied. Objective: The aim of this study was to determine the associations between dietary total, animal, and plant protein intakes as well as the animal-to-plant protein (AP) intake ratio with insulin resistance in middle-aged and older adults. Methods: This was a cross-sectional analysis in 548 participants (mean ± SD age: 66.2 ± 13.7 y) from the calibration substudy of the AHS-2 (Adventist Health Study 2) cohort. Participants consumed diets with a low AP intake ratio. Dietary intakes of total and particular types of protein were calculated from six 24-h dietary recalls. Participants completed a self-administered questionnaire on demographic, lifestyle, health, diet intake, and physical activity characteristics. Anthropometric variables including weight, height, and waist circumference were measured. Homeostasis model assessment of insulin resistance (HOMA-IR) was calculated by using fasting serum glucose and insulin. Multiple linear regression models were used to test the relations between total and specific protein intakes with insulin resistance. Results: The ranges of dietary intakes of animal and plant protein and the AP intake ratio were 0.4-87.4 and 14.0-79.2 g/d and 0.02-4.43, respectively. Dietary intakes per 10-g/d increments of total protein (β: 0.11; 95% CI: 0.02, 0.21) and animal protein (β: 0.11; 95% CI: 0.01, 0.20) and the AP intake ratio (β: 1.82; 95% CI: 0.80, 2.84) were positively related to HOMA-IR. Plant protein was not significantly related to insulin resistance. Conclusion: Total and animal protein intakes and the AP intake ratio were positively associated with HOMA-IR in adults with relatively a low intake of animal protein and a high consumption of plant protein.

High-intensity aerobic interval training improves aerobic fitness and HbA1c among persons diagnosed with type 2 diabetes

PURPOSE

It remains to be established how high-intensity aerobic interval training (HAIT) affects risk factors associated with type 2 diabetes (TD2). This study investigated effects of HAIT on maximal oxygen uptake (VO_2max), glycated Hemoglobin type A1C (HbA1c), insulin resistance (IR), fat oxidation (FatOx), body weight (BW), percent body fat (%BF), lactate threshold (LT), blood pressure (BP), and blood lipid profile (BLP) among persons with T2D. Results were compared to the effects after a moderate-intensity training (MIT) program.

METHODS

Thirty-eight individuals with T2D completed 12 weeks of supervised training. HAIT consisted of 4 × 4 min of walking or running uphill at 85-95% of maximal heart rate, and MIT consisted of continuous walking at 70-75% of maximal heart rate.

RESULTS

A 21% increase in VO_2max (from 25.6 to 30.9 ml kg^-1 min^-1, p < 0.001), and a reduction in HbA1c by -0.58% points (from 7.78 to 7.20%, p < 0.001) was found in HAIT. BW and body mass index (BMI) was reduced by 1.9% (p < 0.01). There was a tendency towards an improved FatOx at 60% VO_2max (14%, p = 0.065). These improvements were significant different from MIT. Both HAIT and MIT increased velocity at LT, and reduced %BF, waist circumference, hip circumference, and BP, with no significant differences between the two groups. Correlations were found between change in VO_2max and change in HbA1c when the two intervention groups were combined (R = -0.52, p < 0.01).

CONCLUSION

HAIT is an effective exercise strategy to improve aerobic fitness and reduce risk factors associated with T2D.

Body weight, fat distribution and colorectal cancer risk: a report from cohort studies of 134255 Chinese men and women

OBJECTIVE

To evaluate the association of body size and fat distribution with risk of colorectal cancer (CRC) in Chinese men and women.

DESIGN

Population-based, prospective cohort study.

SUBJECTS

The analysis included 134 255 Chinese adults enrolled in the Shanghai Women’s Health Study and the Shanghai Men’s Health Study, with an average follow-up of 11.0 and 5.5 years, respectively.

MEASUREMENTS

Waist circumference (WC), body mass index (BMI) and waist-to-hip ratio (WHR) were measured by trained interviewers at baseline. Multivariable Cox models were used to calculate adjusted hazard ratios (HRs) for incident CRC.

RESULTS

A total of 935 incident CRC cases were identified. Both measures of general adiposity (measured by BMI) and central adiposity (measured by WHR and WC) were significantly associated with increased risk of colon cancer in men but not in women. Multivariable adjusted HRs for colon cancer in men in the highest compared with the lowest quintiles were 2.15 (95% CI: 1.35-3.43; P for trend = 0.0006) for BMI, 1.97 (95% CI: 1.19-3.24; P for trend = 0.0004) for WHR and 2.00 (95% CI: 1.21-3.29; P for trend = 0.0002) for WC. The BMI-associated risk was attenuated in analyses stratified by WHR, while the WHR-associated risk remained significant in the high BMI stratum (HR for comparison of extreme tertiles of WHR: 3.38, 95% CI: 1.47-7.75; P for trend =0.0002). None of these anthropometric measures were significantly associated with rectal cancer.

CONCLUSION

Obesity, particularly central obesity, was associated with increased risk of colon cancer in men.

Alternate-Day High-Fat Diet Induces an Increase in Mitochondrial Enzyme Activities and Protein Content in Rat Skeletal Muscle

Long-term high-fat diet increases muscle mitochondrial enzyme activity and endurance performance. However, excessive calorie intake causes intra-abdominal fat accumulation and metabolic syndrome. The purpose of this study was to investigate the effect of an alternating day high-fat diet on muscle mitochondrial enzyme activities, protein content, and intra-abdominal fat mass in rats. Male Wistar rats were given a standard chow diet (CON), high-fat diet (HFD), or alternate-day high-fat diet (ALT) for 4 weeks. Rats in the ALT group were fed a high-fat diet and standard chow every other day for 4 weeks. After the dietary intervention, mitochondrial enzyme activities and protein content in skeletal muscle were measured. Although body weight did not differ among groups, the epididymal fat mass in the HFD group was higher than those of the CON and ALT groups. Citrate synthase and beta-hydroxyacyl CoA dehydrogenase activities in the plantaris muscle of rats in HFD and ALT were significantly higher than that in CON rats, whereas there was no difference between HFD and ALT groups. No significant difference was observed in muscle glycogen concentration or glucose transporter-4 protein content among the three groups. These results suggest that an alternate-day high-fat diet induces increases in mitochondrial enzyme activities and protein content in rat skeletal muscle without intra-abdominal fat accumulation.

Sonographically Assessed Intra-Abdominal Fat And Cardiometabolic Risk Factors in Adolescents with Extreme Obesity

OBJECTIVE

The metabolic and cardiovascular risk of obesity is predominantly defined through the amount of intra-abdominal fat (IAF). Regarding this risk and the benefits of weight reduction gender-specific differences have been described. The aim of this study was to examine the gender-specific relationship between IAF assessed via ultrasound and the cardiometabolic risk profile in extremely obese adolescents before and after weight loss.

METHODS

In 107 consecutively admitted adolescents (n = 59 girls, mean age 15.4 ± 2.6 years boys and 15.1 ± 2.1 years girls, mean BMI z-score 3.2 ± 0.6 boys and 3.5 ± 0.6 girls) anthropometric and fasting laboratory chemical parameters were measured before and after an in-patient long-term therapy (mean durance 5.6 ± 2.3 months). IAF was determined by measuring the intra-abdominal depth (IAD) via ultrasound.

RESULTS

IAD was higher in boys as compared to girls (58.0 ± 22.4 mm vs. 51.3 ± 16.0 mm). IAD values were positively associated with BMI-z scores, waist circumferences, HOMA-IR and serum levels of x03B3;GT, hs-CRP and IL-6 in both genders. In boys, but not in girls, IAD was significantly correlated with systolic and diastolic blood pressure, serum levels of triglycerides, ALT as well as adiponectin and HDL-cholesterol. After a marked mean weight loss of -27.1 ± 16.2 kg (-20.1 ± 7.9%) in boys and of -20.5 ± 11.5 kg (-17.3 ± 7.1%) in girls, IAD decreased by -20.7 ± 16.2 mm (--32.4 ± 16.9%) in boys and by -18.4 ± 12,7 mm (-34.3 ± 18.4%) in girls, resulting in more pronounced ameliorations of cardiovascular risk factors in boys than in girls.

CONCLUSIONS

The present study indicates that IAF assessed by ultrasound is a good indicator for the cardiometabolic risk factor profile in extremely obese adolescents. Associations between IAF and risk factors are more pronounced in boys than in girls.

A randomized trial comparing the effect of weight loss and exercise training on insulin sensitivity and glucose metabolism in coronary artery disease

AIM

The majority of patients with coronary artery disease (CAD) exhibit abnormal glucose metabolism, which is associated with mortality even at non-diabetic glucose levels. This trial aims to compare the effects of a considerable weight loss and exercise with limited weight loss on glucose metabolism in prediabetic, CAD patients.

METHODS AND RESULTS

Seventy non-diabetic participants with CAD, BMI 28-40 kg/m(2), age 45-75 years were randomized to 12 weeks' aerobic interval training (AIT) at 90% peak heart rate three times weekly or a low energy diet (LED, 800-1,000 kcal/day) for 8-10 weeks followed by 2-4 weeks' weight maintenance diet. Glucose tolerance, insulin action, β-cell function and suppression of lipolysis were assessed using a 3-h oral glucose tolerance test. ISI-composite and ISI-HOMA (=1/HOMA-IR) were calculated as surrogate measures of whole-body and hepatic insulin sensitivity, respectively. Magnetic resonance imaging estimated abdominal adipose tissue. Twenty-six (74%) AIT and 29 (83%) LED participants completed intervention per protocol. LED increased ISI-composite by 55% and ISI-HOMA by 70% (p<0.01) while AIT did not change insulin sensitivity (p>0.7) revealing a significant difference between the groups (p<0.05). No concurrent significant changes in lipolysis, β-cell responsiveness or insulin clearance were seen. Changes in ISI-HOMA and ISI-composite were associated with reduced visceral abdominal fat, waist circumference and body weight. Intention-to-treat analyses (n=64) yielded similar results.

CONCLUSION

LED is superior to AIT in improving insulin sensitivity in prediabetic CAD patients. Changes in insulin sensitivity are associated with decreased visceral abdominal fat, waist circumference and body weight.

Age- and sex-specific causal effects of adiposity on cardiovascular risk factors

Observational studies have reported different effects of adiposity on cardiovascular risk factors across age and sex. Since cardiovascular risk factors are enriched in obese individuals, it has not been easy to dissect the effects of adiposity from those of other risk factors. We used a Mendelian randomization approach, applying a set of 32 genetic markers to estimate the causal effect of adiposity on blood pressure, glycemic indices, circulating lipid levels, and markers of inflammation and liver disease in up to 67,553 individuals. All analyses were stratified by age (cutoff 55 years of age) and sex. The genetic score was associated with BMI in both nonstratified analysis (P = 2.8 × 10(-107)) and stratified analyses (all P < 3.3 × 10(-30)). We found evidence of a causal effect of adiposity on blood pressure, fasting levels of insulin, C-reactive protein, interleukin-6, HDL cholesterol, and triglycerides in a nonstratified analysis and in the <55-year stratum. Further, we found evidence of a smaller causal effect on total cholesterol (P for difference = 0.015) in the ≥55-year stratum than in the <55-year stratum, a finding that could be explained by biology, survival bias, or differential medication. In conclusion, this study extends previous knowledge of the effects of adiposity by providing sex- and age-specific causal estimates on cardiovascular risk factors.

Postprandial plasma incretin hormones in exercise-trained versus untrained subjects

INTRODUCTION

After food ingestion, the incretin hormones, glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP), are secreted by the intestines into circulation where they act on the pancreas to promote insulin secretion. We evaluated the hypothesis that low postprandial plasma insulin levels in lean exercise-trained individuals are associated with low concentrations of incretin hormones.

METHODS

A cross-sectional study was performed to compare postprandial incretin hormone levels in lean endurance exercise-trained individuals (EX; n = 14, ≥40 yr) and age- and sex-matched, nonobese, sedentary control subjects (CON, n = 14). The main outcome measures were GLP-1, GIP, insulin, and glucose incremental areas under the curve (AUC) as measured in plasma samples collected during a 2-h,75-g oral glucose tolerance test (OGTT).

RESULTS

The EX group had lower body fat percentage (14.6% ± 1.1% vs 23.3% ± 1.7%, P = 0.0002) and higher maximal oxygen uptake (53 ± 2 vs 34 ± 2, P < 0.0001) than CON. Glucose AUC did not differ between groups (P = 0.20). Insulin AUC was lower in EX (2.5 ± 0.5 vs 4.2 ± 1.2 μU·mL·1000 min, P = 0.02). No differences were observed between groups (EX and CON, respectively) for GLP-1 AUC (3.5 ± 0.7 vs 4.1 ± 1.1 pmol·min·100 L, P = 0.61) or GIP AUC (19.2 ± 1.4 vs 18.0 ± 1.4 pg·min·1000 mL; P = 0.56). In CON, insulin AUC was correlated with AUC for GLP-1 (r = 0.53, P = 0.05) and GIP (r = 0.71, P = 0.004), but no such correlations were observed in EX (both P ≥ 0.67).

CONCLUSIONS

Low postprandial insulin levels in lean exercise-trained individuals are not attributable to lower incretin hormone concentrations. However, exercise may decrease the dependency of postprandial insulin levels on incretin hormones.

Ageing, adipose tissue, fatty acids and inflammation

A common feature of ageing is the alteration in tissue distribution and composition, with a shift in fat away from lower body and subcutaneous depots to visceral and ectopic sites. Redistribution of adipose tissue towards an ectopic site can have dramatic effects on metabolic function. In skeletal muscle, increased ectopic adiposity is linked to insulin resistance through lipid mediators such as ceramide or DAG, inhibiting the insulin receptor signalling pathway. Additionally, the risk of developing cardiovascular disease is increased with elevated visceral adipose distribution. In ageing, adipose tissue becomes dysfunctional, with the pathway of differentiation of preadipocytes to mature adipocytes becoming impaired; this results in dysfunctional adipocytes less able to store fat and subsequent fat redistribution to ectopic sites. Low grade systemic inflammation is commonly observed in ageing, and may drive the adipose tissue dysfunction, as proinflammatory cytokines are capable of inhibiting adipocyte differentiation. Beyond increased ectopic adiposity, the effect of impaired adipose tissue function is an elevation in systemic free fatty acids (FFA), a common feature of many metabolic disorders. Saturated fatty acids can be regarded as the most detrimental of FFA, being capable of inducing insulin resistance and inflammation through lipid mediators such as ceramide, which can increase risk of developing atherosclerosis. Elevated FFA, in particular saturated fatty acids, maybe a driving factor for both the increased insulin resistance, cardiovascular disease risk and inflammation in older adults.

Waist circumference measures: cutoff analyses to detect obesity and cardiometabolic risk factors in a Southeast Brazilian middle-aged men population--a cross-sectional study

Background

Low-cost practical and reliable tools to evaluated obesity-related cardiometabolic diseases are of clinical practice and public heath relevance worldwide. The aims of this cross-sectional study were to determine the anatomical point of waist circumference that best identify overweight, obesity and central obesity in Southeast Brazilian middle-aged men and to test the relationships of its cutoff points with metabolic syndrome (MetS), insulin resistance (IR) and cardiometabolic risk factors.

Methods

Three hundred men [age: 51 (47–54)] underwent anthropometric, body composition, clinical, sociodemographic and blood plasma biochemical evaluations.

Results

The umbilical line circumference (WC_UL) was the best predictor for overweight (total body fat ≥ 20%; cutoff point: 88.8 cm), obesity (total body fat ≥ 25%; cutoff point: 93.4 cm) and central obesity (abdominal area fat ≥ 34.6%; cutoff point: 95.6 cm) as measured by dual beam X-ray absorptiometry. Subjects with WC_UL ≥ 88.8 cm or ≥ 93.4 cm showed significantly higher values for MetS, IR and cardiometabolic risk factors (i.e. glucose and lipid profiles, blood pressure). The occurrence of WC_UL ≥ 88.8 cm was positively associated (p <0.01) with the prevalence of MetS and cardiometabolic risk factors and increased the central obesity prevalence by 19.3% while that of WC_UL ≥ 93.4 cm was associated with the prevalence of MetS, IR and cardiometabolic risk factors.

Conclusions

WC_UL measure seems to be the best predictor for overweight, obesity and central obesity in urban residents Southeast Brazilian middle-aged men; and the WC_UL cutoff point (88.8 cm) is significantly associated with MetS, IR and cardiometabolic risk factors in the studied population.

Gender-assortative waist circumference in mother-daughter and father-son pairs, and its implications. An 11-year longitudinal study in children (EarlyBird 59)

BACKGROUND/OBJECTIVES

Body mass index (BMI) is reportedly gender assortative (mother-daughter, father-son) in contemporary children. We investigated the corresponding transmission of waist circumference (WC) and its implications.

METHODS

We measured parental WC at baseline and WC, height, weight and para-umbilical skin-fold (USF) annually in their offspring from 5 to 15 years (n = 223 trios). Parents were deemed normal metabolic risk (NR) or high risk (HR) according to World Health Organization (WHO) cut-points for WC (mothers 80 cm, fathers 94 cm). The residual from WC adjusted for BMI (WC|BMI ) was used as a surrogate for excess intra-abdominal fat, and its association with insulin resistance (HOMA2-IR) was sought.

RESULTS

WC and USF were both gender assortative, while WC|BMI was not. WC was greater by 1.62 cm (P < 0.05, confidence interval [CI]: 0.09-3.16) and USF by 0.37 cm (P < 0.01, CI: 0.19-0.56) among the daughters (but not the sons) of HR compared with those of NR mothers, and by 1.32 cm (P < 0.05, CI: 0.09-2.55) and 0.18 cm (P < 0.05, CI: 0.04-0.32), respectively in the corresponding father-son (but not father-daughter) pairings. No such differences could be demonstrated for WC|BMI . A standard deviation score 1(SDS) change in WC|BMI , independent of BMI, was associated with a 7.14% change in IR in girls (P < 0.01, CI: 1.76-12.80) and 8.02% in boys (P < 0.001, CI: 2.93-13.36), but there was no relationship between IR and USF.

CONCLUSION

The relationship of offspring WC to metabolic health and to parental size is complex. Subcutaneous abdominal fat is gender assortative but harmless, while intra-abdominal fat (its surrogate in this analysis) is unrelated to parental waist circumference, but metabolically harmful.

Waist circumference is a better predictor than body mass index of insulin resistance in type 2 diabetes

Summay:

BACKGROUND

Insulin resistance is an important pathogenic factor in type 2 diabetes patents. An easy and efficiency measurement predicting insulin resistance; which can be done easily by type 2 patients is desired.

OBJECTIVE

To examine whether waist circumference is a better predictor of insulin resistance in type 2 diabetes than body mass index (BMI).

METHODS

From a population of 1356 registered diabetic patients, 144 who met (1) aged between 30 and 75 years, (2) being Chinese, (3) having had type 2 diabetes for more than one year, and (4) having been taking gliclazide and metformin for more than 6 months were enrolled in this study. The main outcome evaluated is the associations of HOMA insulin resistance index (HOMA index); which were assessed using multiple linear regression analysis.

RESULTS

The coefficients of multiple regression analysis with stepwise model showed that waist circumference (β = 0.35, p < 0.001) but not BMI (β = 0.01, p = 0.94), adiponectin (β = -0.25, p = 0.04) and hemoglobulin A1c% (HbA1c) (β = 0.25, p = 0.01) were the main predictors of HOMA index.

CONCLUSIONS

These initial findings indicate that waist circumference is a better predictor of insulin resistance in type 2 diabetes than BMI.

Associations of trunk fat depots with insulin resistance, β cell function and glycaemia--a multiple technique study

Objective

Central (truncal) adiposity is associated strongly with insulin resistance and diabetes. There are very few reports comparing methods of trunk fat measurement in their ability to predict glycaemia and insulin resistance. We report a comparative analysis of different trunk fat measurements in predicting glycaemia and insulin resistance in middle aged Indian men.

Materials and Methods

Trunk fat measurements were performed using anthropometry, magnetic resonance imaging (MRI), dual-energy X-ray absorptiometry (DXA) and computed tomography (CT) on 128 men. Additional measurements were taken to characterise insulin resistance (Matsuda index) and beta cell function (Insulinogenic Index), glycaemia (fasting and 120 min glucose concentrations). Using residual approach we compared the ability of different trunk fat measurement techniques to predict insulin resistance, beta cell function and glycaemia.

Results

There was a strong association between trunk fat measures from each technique with glycaemia and insulin resistance indices but not with the Insulinogenic Index. Insulin resistance and glycaemia, were best predicted using anthropometric measurements, notably by waist circumference and subscapular skinfold thickness. Neither MRI measures of trunk or visceral fat nor DXA trunk fat added significantly. CT liver density contributed to some extent to predict insulin resistance and 120 min glucose after anthropometric measurements.

Conclusions

Our results suggest that, in Indian men, anthropometric measurements are good predictors of glycaemia and insulin resistance. Other complex measurements such as MRI, DXA and CT make only a small addition to the prediction. This finding supports the application of anthropometry for determining trunk fat in clinical and epidemiological settings.