Abdominal obesity and other risk factors largely explain the high CRP in indigenous Australians relative to the general population, but not gender differences: a cross-sectional study

Associations of iron metabolism and inflammation with all-cause and cardiovascular mortality in a large NHANES community sample: Moderating and mediating effects

BACKGROUND AND AIMS

This study aimed to assess the associations between serum iron concentration, C-reactive protein (CRP) concentration and the risk of all-cause mortality and cardiovascular mortality in the general population and to explore potential mediating and moderating effects.

METHODS AND RESULTS

This study analyzed data from the National Health and Nutrition Examination Survey spanning the years 1999-2010, encompassing 23,634 participants. Cox proportional hazards regression models were employed to investigate the independent associations of serum iron and CRP with all-cause and cardiovascular mortality. Moderation and mediation analyses explored the moderating effect of CRP on the association between the serum iron concentration and all-cause and cardiovascular mortality, and the mediating role of the serum iron concentration in the association between the CRP concentration and all-cause and cardiovascular mortality. After multivariate adjustments in the Cox model, serum iron and CRP levels were independently correlated with both all-cause and cardiovascular mortality risk. Moderation analyses revealed a more pronounced correlation between the serum iron concentration and both all-cause and cardiovascular mortality in participants with higher CRP levels. Mediation analysis indicated that the serum iron concentration partly mediated the impact of CRP on the risk of all-cause mortality (13.79%) and cardiovascular mortality (24.12%).

CONCLUSION

Serum iron and CRP are independently associated with all-cause and cardiovascular mortality. Moreover, the associations between serum iron concentrations and both all-cause and cardiovascular mortality are more pronounced in individuals with elevated CRP. Serum iron partially mediates the effect of CRP on all-cause and cardiovascular mortality.

Exiting the Anthropocene: Achieving personal and planetary health in the 21st century

Planetary health provides a perspective of ecological interdependence that connects the health and vitality of individuals, communities, and Earth's natural systems. It includes the social, political, and economic ecosystems that influence both individuals and whole societies. In an era of interconnected grand challenges threatening health of all systems at all scales, planetary health provides a framework for cross-sectoral collaboration and unified systems approaches to solutions. The field of allergy is at the forefront of these efforts. Allergic conditions are a sentinel measure of environmental impact on human health in early life-illuminating how ecological changes affect immune development and predispose to a wider range of inflammatory noncommunicable diseases (NCDs). This shows how adverse macroscale ecology in the Anthropocene penetrates to the molecular level of personal and microscale ecology, including the microbial systems at the foundations of all ecosystems. It provides the basis for more integrated efforts to address widespread environmental degradation and adverse effects of maladaptive urbanization, food systems, lifestyle behaviors, and socioeconomic disadvantage. Nature-based solutions and efforts to improve nature-relatedness are crucial for restoring symbiosis, balance, and mutualism in every sense, recognizing that both personal lifestyle choices and collective structural actions are needed in tandem. Ultimately, meaningful ecological approaches will depend on placing greater emphasis on psychological and cultural dimensions such as mindfulness, values, and moral wisdom to ensure a sustainable and resilient future.

A Safe GDNF and GDNF/BDNF Controlled Delivery System Improves Migration in Human Retinal Pigment Epithelial Cells and Survival in Retinal Ganglion Cells: Potential Usefulness in Degenerative Retinal Pathologies

We assessed the sustained delivery effect of poly (lactic-co-glycolic) acid (PLGA)/vitamin E (VitE) microspheres (MSs) loaded with glial cell-derived neurotrophic factor (GDNF) alone (GDNF-MSs) or combined with brain-derived neurotrophic factor (BDNF; GDNF/BDNF-MSs) on migration of the human adult retinal pigment epithelial cell-line-19 (ARPE-19) cells, primate choroidal endothelial (RF/6A) cells, and the survival of isolated mouse retinal ganglion cells (RGCs). The morphology of the MSs, particle size, and encapsulation efficiencies of the active substances were evaluated. In vitro release, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cell viability, terminal deoxynucleotidyl transferase (TdT) deoxyuridine dUTP nick-end labelling (TUNEL) apoptosis, functional wound healing migration (ARPE-19; migration), and (RF/6A; angiogenesis) assays were conducted. The safety of MS intravitreal injection was assessed using hematoxylin and eosin, neuronal nuclei (NeuN) immunolabeling, and TUNEL assays, and RGC in vitro survival was analyzed. MSs delivered GDNF and co-delivered GDNF/BDNF in a sustained manner over 77 days. The BDNF/GDNF combination increased RPE cell migration, whereas no effect was observed on RF/6A. MSs did not alter cell viability, apoptosis was absent in vitro, and RGCs survived in vitro for seven weeks. In mice, retinal toxicity and apoptosis was absent in histologic sections. This delivery strategy could be useful as a potential co-therapy in retinal degenerations and glaucoma, in line with future personalized long-term intravitreal treatment as different amounts (doses) of microparticles can be administered according to patients’ needs.

Intestinal microbiology shapes population health impacts of diet and lifestyle risk exposures in Torres Strait Islander communities

Poor diet and lifestyle exposures are implicated in substantial global increases in non-communicable disease burden in low-income, remote, and Indigenous communities. This observational study investigated the contribution of the fecal microbiome to influence host physiology in two Indigenous communities in the Torres Strait Islands: Mer, a remote island where a traditional diet predominates, and Waiben a more accessible island with greater access to takeaway food and alcohol. Counterintuitively, disease markers were more pronounced in Mer residents. However, island-specific differences in disease risk were explained, in part, by microbiome traits. The absence of Alistipes onderdonkii, for example, significantly (p=0.014) moderated island-specific patterns of systolic blood pressure in multivariate-adjusted models. We also report mediatory relationships between traits of the fecal metagenome, disease markers, and risk exposures. Understanding how intestinal microbiome traits influence response to disease risk exposures is critical for the development of strategies that mitigate the growing burden of cardiometabolic disease in these communities.

Molecular Decolonization: An Indigenous Microcosm Perspective of Planetary Health

Indigenous peoples are resilient peoples with deep traditional knowledge and scientific thought spanning millennia. Global discourse on climate change however has identified Indigenous populations as being a highly vulnerable group due to the habitation in regions undergoing rapid change, and the disproportionate burden of morbidity and mortality already faced by this population. Therefore, the need for Indigenous self-determination and the formal recognition of Indigenous knowledges, including micro-level molecular and microbial knowledges, as a critical foundation for planetary health is in urgent need. Through the process of Indigenous decolonization, even at the smallest molecular scale, we define a method back to our original selves and therefore to our planetary origin story. Our health and well-being is directly reflected at the planetary scale, and we suggest, can be rooted through the concept of molecular decolonization, which through the English language emerged from the ‘First 1000 Days Australia’ and otherwise collectively synthesized globally. It is through our evolving understanding of decolonization at a molecular level, which many of our Indigenous cultural and healing practices subtly embody, that we are better able to translate the intricacies within the current Indigenous scientific worldview through Western forms of discourse.

Baseline serum C-reactive protein levels may predict antidepressant treatment responses in patients with major depressive disorder

BACKGROUND

Inflammation has been shown previously to predict antidepressant treatment response. This retrospective study was conducted to test if the baseline serum C-reactive protein (CRP) levels could predict antidepressant treatment responses in a Chinese sample.

METHODS

75 adult inpatients (26 male, 49 female) with major depressive disorder (MDD) diagnosed according to DSM-5 were included in this study. Sociodemographic and clinical features, baseline CRP levels, 17-item Hamilton Depression Rating Scale (HDRS-17) and Hamilton Anxiety Rating Scale (HARS) scores assessed at baseline and weeks 1, 2, 3 and 4 were then collected. Afterwards patients were divided into two groups: the low CRP group (baseline CRP < 1 mg/L, n = 47) and the high CRP group (baseline CRP ≥ 1 mg/L, n = 28). Depression severity and treatment response were compared between the two groups.

RESULTS

Repeated-measures ANOVA showed a significant group * assessments interaction in HDRS-17 scores (F = 4.754; p = 0.005). Post-hoc test showed that the two groups differed in HDRS-17 scores at week 4 (F = 6.698; p = 0.012), with the low CRP group having lower HDRS-17 scores than the high CRP group. Moreover, the low CRP group exhibited higher percent reduction in HDRS-17 scores at week 3 (F = 5.016; p = 0.028) and week 4 (F = 9.865; p = 0.003) as compared to the high CRP group. Cox proportional hazard model showed that the remission rate was higher in the low CRP group (p = 0.010).

LIMITATIONS

Patients received uncontrolled antidepressant therapy and the sample size was limited.

CONCLUSIONS

Baseline serum CRP levels may predict antidepressant treatment responses in patients with MDD and patients with higher levels of CRP were less likely to get remission.

Examining the relationship between body mass index and adverse cardio-metabolic profiles among Australian Indigenous and non-Indigenous young adults

Australian Indigenous young people have a 10-fold excess of deaths from ischaemic heart disease compared with non-Indigenous Australians, yet the reasons behind this remain understudied. This paper aims to describe cardio-metabolic profiles among Australian Indigenous (n = 459) and non-Indigenous (n = 117) young adults (21-27 years). The association between body size and an adverse cardio-metabolic profile (≥3 abnormal cardio-metabolic markers) is assessed by gender and urban/rural residence, employing regression analyses. The prevalence of obesity was highest among urban Indigenous participants, both males and females (22% and 23%, respectively). Overall, BMI showed a significant positive association with an adverse cardio-metabolic profile. Moreover, adverse cardio-metabolic profile was present in a substantial proportion of Indigenous participants even in overweight and normal BMI categories. Among females, this could reflect elevated waist circumference, which was present in half of those of normal weight. Remote Indigenous females had the highest predicted probability of having an adverse cardio-metabolic profile across all BMI categories (13% for underweight, 54% for normal BMI, 93% for overweight, and 99% for obese). Our findings highlight the associations between obesity and adverse cardio-metabolic profiles among Indigenous and non-Indigenous youth. Culturally-relevant strategies that address lifestyle risks, including access to healthy food, are urgently needed in this age group.

Novel Association of High C-Reactive Protein Levels and A69S at Risk Alleles in Wet Age-Related Macular Degeneration Women

Purpose

To explore the relationship between plasma C-reactive protein (CRP) levels, the main ARMS2 gene single nucleotide polymorphism (SNP), and gender in patients with neovascular age-related macular degeneration (wet AMD).

Methods

Our study included 131 patients with wetAMD [age-related eye disease study (AREDS) category 4] and 153 control participants (AREDS category 1) from two Spanish retinal units. CRP levels were determined on blood samples by high-sensitivity ELISA assay. According to their CRP level, subjects were categorized into three well-established CRP categories: low (<1.00 mg/L, L-CRP), moderate (1–2.99 mg/L, M-CRP), and high (>3.00 mg/L, H-CRP). Genomic DNA was extracted from oral swabs using QIAcube (Qiagen, Hilden, Germany) and the A69S; rs10490924 of ARMS2 gene was genotyped by allelic discrimination with validated TaqMan assays (Applied Biosystems, Foster City, CA, USA). Univariate and multivariate logistic regression adjusted for age was used to analyze the genomic frequencies and to calculate odds ratio (OR) using SNPStats software.

Results

Considering CRP risk categories, H-CRP group showed a significant [OR 4.0 (1.9–8.3)] association with wetAMD compared to L-CRP group. The risk genotypes of A69S (TT) SNPs showed an association with wetAMD risk [OR 14.0 (4.8–40.8)]. Interestingly, the gender stratification of the CRP categories showed a significant increase in CRP levels in wetAMD women compared with control women [OR 6.9 (2.2–22.3)] and with wetAMD men [OR 4.6 (1.3–16.9)]. In addition, the subgroup analysis of CRP within A69S genotype and gender showed a link in women between the A69S and CRP levels in the AMD group compared to controls [OR 4.2 (1.4–12.6)].

Conclusion

Our study shows, for the first time, that a different genetic association related with gender could contribute to AMD risk. As a consequence, the risk of female gender in the different CRP levels and A69S SNP frequencies could be taken into consideration to the established risk relationship of high levels of CRP and its association with risk A69S genotype.

High Baseline Levels of Tumor Necrosis Factor Receptor 1 Are Associated With Progression of Kidney Disease in Indigenous Australians With Diabetes: The eGFR Follow-up Study

OBJECTIVE

To examine the association between soluble tumor necrosis factor receptor 1 (sTNFR1) levels and kidney disease progression in Indigenous Australians at high risk of kidney disease.

RESEARCH DESIGN AND METHODS

This longitudinal observational study examined participants aged ≥18 years recruited from >20 sites across diabetes and/or kidney function strata. Baseline measures included sTNFR1, serum creatinine, urine albumin-to-creatinine ratio (uACR), HbA_1c, C-reactive protein (CRP), waist-to-hip ratio, systolic blood pressure, and medical history. Linear regression was used to estimate annual change in estimated glomerular filtration rate (eGFR) for increasing sTNFR1, and Cox proportional hazards were used to estimate the hazard ratio (HR) and 95% CI for developing a combined renal outcome (first of a ≥30% decline in eGFR with a follow-up eGFR <60 mL/min/1.73 m², progression to renal replacement therapy, or renal death) for increasing sTNFR1.

RESULTS

Over a median of 3 years, participants with diabetes (n = 194) in the highest compared with the lowest quartile of sTNFR1 experienced significantly greater eGFR decline (-4.22 mL/min/1.73 m²/year [95% CI -7.06 to -1.38]; P = 0.004), independent of baseline age, sex, eGFR, and uACR. The adjusted HR (95% CI) for participants with diabetes per doubling of sTNFR1 for the combined renal outcome (n = 32) was 3.8 (1.1-12.8; P = 0.03). No association between sTNFR1 and either renal outcome was observed for those without diabetes (n = 259).

CONCLUSIONS

sTNFR1 is associated with greater kidney disease progression independent of albuminuria and eGFR in Indigenous Australians with diabetes. Further research is required to assess whether TNFR1 operates independently of other metabolic factors associated with kidney disease progression.

An Overview of Indigenous Australian Disadvantage in Terms of Ischaemic Heart Disease

BACKGROUND

Indigenous Australians experience poorer health outcomes than non-Indigenous Australians and a significant life expectancy gap exists. Ischaemic heart disease (IHD) represents the leading specific cause of death in Indigenous Australians and is a significant, if not the most significant, contributor to the mortality gap. With this narrative review we aim to describe the burden of IHD within the Indigenous Australian community and explore the factors driving this disparity.

METHODS

A broad search of the literature was undertaken utilising an electronic search of the PubMed database along with national agency databases-the Australian Institute of Health and Welfare (AIHW) and the Australian Bureau of Statistics (ABS).

RESULTS

A complex interplay between multiple factors contributes to the excess burden of IHD in the Indigenous Australian population: CONCLUSIONS: In terms of IHD, Indigenous Australians experience disadvantage at multiple stages of the disease process. Ongoing efforts are needed to continue to inform clinicians of both this disadvantage and strategies to assist negating it. Further research is needed to develop evidence based practices which may help reduce this disparity in outcomes.

Influence of Central Obesity Assessed by Conicity Index on Lung Age in Young Adults

INTRODUCTION

Central obesity is an emerging public health problem in young adults which compromises lung mechanics. Conicity Index (CI) is a simple anthropometric measure to assess central adiposity. The concept of lung age relates to a person's current lung function at which his/her lung function would be considered abnormal in relation to the present actual age.

AIM

To determine the effect of central obesity by CI on lung age in young adults.

MATERIALS AND METHODS

A total of 319 young adults in the age group 18-25 years were recruited for this cross-sectional observational study. Written informed consent and Institutional Ethical Clearance (IEC) approval were obtained. Anthropometric parameters were measured and CI was calculated using the following formula: CI = Waist Circumference (WC) (m)/ [0.109 X√ {Bodyweight (kg)/ Height (m)}] where 0.109 is a constant. Spirometry was performed and all the lung volumes and capacities were obtained.

RESULTS

There was a significant increase in mean values of CI in obese young adults compared to non obese (1.36±0.15 and 1.16±0.08, p<0.001). The effect of central obesity on lung age in young adults was compared using an independent t-test. Mean of lung age was significantly higher in centrally obese young adults compared to non obese 23.87±3.03 and 21.30±2.6, p<0.001) which was statistically significant.

CONCLUSION

Lung age is significantly increased in centrally obese young adults compared to non obese. Hence, lung age can be used as a potential psychological tool to show an individual with central obesity that there is premature aging of their lungs.

Central obesity and risks of cardiovascular events and mortality in prevalent hemodialysis patients

BACKGROUND

To date, no attempt has been made to assess the best anthropometric method for defining abdominal adiposity in hemodialysis (HD) patients or to determine whether the quantity of intra-abdominal fat relates to morbidity and mortality in that population. We aimed to describe the prevalence of central obesity in HD patients and to investigate the relationship between central obesity assessed by anthropometric variables, and composite outcomes, cardiovascular morbidity and mortality among HD patients and whether this parameter correlates with intra-abdominal fat assessed by computed tomography scan (CT scan).

METHODS

The procedures followed were in accord with the ethical standards of the committee on human experimentation of our institution. Informed oral consent was obtained from all patients. This was a cross-sectional study of 120 prevalent HD patients. Anthropometric measurements including body mass index, conicity index (Ci), waist-hip ratio (WHR), waist circumference (WC), waist-to-height ratio (WHtR), and visceral adiposity index (VAI) were recorded. Visceral and subcutaneous abdominal fat were assessed by CT scan. Comorbidity was scored for both the Charlson comorbidity index (CCI) and Davies comorbidity index.

RESULTS

Twenty-eight patients (23.3%) were centrally obese based on anthropometry. By linear regression analysis, Ci, WHR, and VAI were predictors of CT assessed central obesity; p 0.042, 0.001, and 0.010, respectively. On assessment of the relationship between the abdominal obesity and the comorbidity indices, there was a positive significant correlation between Ci and CCI (p 0.025) and Davies score (p 0.002) which are predictors of mortality. During the mean follow-up period (3.2 years), 56 patients reached the composite outcome; eight patients died and 48 experienced CV events. Central obesity measured by anthropometry was a predictor of composite outcomes, cardiovascular morbidity, and mortality in HD patients by regression analysis and cox regression model. Only WC and WHtR did not predict mortality.

CONCLUSION

Ci, WHR, and VAI are cheap alternatives for accurate assessment of morbidity and mortality risk in centrally obese prevalent HD patients.

Kimberley Indigenous mental health: An examination of metabolic syndrome risk factors

OBJECTIVE

There is an increased risk of physical health comorbidities in people with a mental illness. This paper examines the metabolic syndrome parameters for the general population, indigenous Australians and people with a mental illness, and compares them to a sample of predominantly indigenous adults with mental health problems.

DESIGN

A longitudinal (24 month) audit of patient medical records was conducted between February 2011 and March 2013.

SETTING

The Kimberley Mental Health and Drug Service in Broome, Western Australia.

PARTICIPANTS

Largely indigenous adults with a mental illness. Sample numbers increased from 56 at baseline (80% indigenous) to 136 at 18 months (70% indigenous).

MAIN OUTCOME MEASURES

Waist circumference, blood pressure, fasting lipids, and fasting blood glucose.

RESULTS

Preliminary assessment of the data indicates a high percentage of abnormalities at baseline and at the 18 month period on all four parameters, yet not all patients were assessed on a regular basis.

CONCLUSIONS

Abnormalities in metabolic profiles consistent with the non-Indigenous mental health population were found. There are considerable challenges to implementing regular monitoring of physical and metabolic profiles of indigenous people in rural and remote communities.

Nutrient intakes associated with elevated serum C-reactive protein concentrations in normal to underweight breastfeeding women in Northern Kenya

OBJECTIVES

Low-grade elevation of C-reactive protein (CRP) is a non-specific inflammatory marker, used as a predictor for cardiovascular disease development and chronic inflammatory risks. Research investigating dietary influences on inflammation has focused primarily on the relationship between dietary characteristics, CRP elevation and BMI in the populations at greatest risk for cardiovascular disease, namely those in the overweight and obese ranges, often in clinical settings and/or among those middle aged or older, leaving little information about normal to underweight populations of reproductive age in ecological settings. This study evaluates impacts of dietary nutrients on serum CRP levels in a population of predominantly underweight to normal weight adult women experiencing the additional nutritional demands of lactation.

METHODS

Data from non-overweight breastfeeding Ariaal women of Kenya collected in 2006 were used (n = 194). Logistic regression models were applied using low-grade CRP elevation (hsCRP > 3 mg/L) as the outcome variable and dietary nutrients, age, BMI, and serum retinol as predictors.

RESULTS

Models showed that energy intake (Kcal) and age were positive predictors of CRP elevation while folate intake, total vitamin A intake, and serum retinol concentration were protective against CRP elevation. Unlike previous studies among higher BMI populations, this study found no significant effect of dietary lipids/fatty acids or BMI on CRP elevation.

CONCLUSIONS

The effects of specific dietary nutrients on inflammatory status may vary with BMI or, in women, reproductive status. Further research should investigate the role of dietary fats, fatty acids, and antioxidant vitamins across populations with a wide range of BMI, including postpartum women.

Effect of periodontal therapy on arterial structure and function among aboriginal australians: a randomized, controlled trial

Observational studies and nonrandomized trials support an association between periodontal disease and atherosclerotic vascular disease. Both diseases occur frequently in Aboriginal Australians. We hypothesized that nonsurgical periodontal therapy would improve measures of arterial function and structure that are subclinical indicators of atherosclerotic vascular disease. This parallel-group, randomized, open label clinical trial enrolled 273 Aboriginal Australians aged ≥18 years with periodontitis. Intervention participants received full-mouth periodontal scaling during a single visit, whereas controls received no treatment. Prespecified primary end points measured 12-month change in carotid intima-media thickness, an indicator of arterial structure, and 3- and 12-month change in pulse wave velocity, an indicator of arterial function. ANCOVA used complete case data to evaluate treatment group differences. End points could be calculated for 169 participants with follow-up data at 3 months and 168 participants at 12 months. Intima-media thickness decreased significantly after 12 months in the intervention group (mean reduction=-0.023 [95% confidence interval {CI}, -0.038 to -0.008] mm) but not in the control group (mean increase=0.002 [95% CI, -0.017 to 0.022] mm). The difference in intima-media thickness change between treatment groups was statistically significant (-0.026 [95% CI, -0.048 to -0.003] mm; P=0.03). In contrast, there were no significant differences between treatment groups in pulse wave velocity at 3 months (mean difference, 0.06 [95% CI, -0.17 to 0.29] m/s; P=0.594) or 12 months (mean difference, 0.21 [95% CI, -0.01 to 0.43] m/s; P=0.062). Periodontal therapy reduced subclinical arterial thickness but not function in Aboriginal Australians with periodontal disease, suggesting periodontal disease and atherosclerosis are significantly associated.

Evidence for low high-density lipoprotein cholesterol levels in Australian indigenous peoples: a systematic review

Background

Low plasma high-density lipoprotein cholesterol (HDL-C) levels are a strong, independent, but poorly understood risk factor for cardiovascular disease (CVD). Although this atherogenic lipid abnormality has been widely reported in Australia’s Indigenous peoples, Aboriginal and Torres Strait Islanders, the evidence has not come under systematic review. This review therefore examines published data for Indigenous Australians reporting 1) mean HDL-C levels for both sexes and 2) factors associated with low HDL-C.

Methods

PubMed, Medline and Informit ATSI Health databases were systematically searched between 1950 and 2012 for studies on Indigenous Australians reporting mean HDL-C levels in both sexes. Retrieved studies were evaluated by standard criteria. Low HDL-C was defined as: <1.0 mmol/L. Analyses of primary data associating measures of HDL-C with other CVD risk factors were also performed.

Results

Fifteen of 93 retrieved studies were identified for inclusion. These provided 58 mean HDL-C levels; 29 for each sex, most obtained in rural/regional (20%) or remote settings (60%) and including 51–1641 participants. For Australian Aborigines, mean HDL-C values ranged between 0.81-1.50 mmol/L in females and 0.76-1.60 mmol/L in males. Two of 15 studies reported HDL-C levels for Torres Strait Islander populations, mean HDL-C: 1.00 or 1.11 mmol/L for females and 1.01 or 1.13 mmol/L for males. Low HDL-C was observed only in rural/regional and remote settings - not in national or urban studies (n = 3) in either gender. Diabetes prevalence, mean/median waist-to-hip ratio and circulating C-reactive protein levels were negatively associated with HDL-C levels (all P < 0.05). Thirty-four per cent of studies reported lower mean HDL-C levels in females than in males.

Conclusions

Very low mean HDL-C levels are common in Australian Indigenous populations living in rural and remote communities. Inverse associations between HDL-C and central obesity, diabetes prevalence and inflammatory markers suggest a particularly adverse CVD risk factor profile. An absence of sex dichotomy in HDL-C levels warrants further investigation.

Gender variations in waist circumference levels between Aboriginal and non-Aboriginal Australian populations: a systematic review

OBJECTIVES

To compare gender-specific waist circumference (WC) levels of Aboriginal Australians with non-Aboriginal Australians.

METHODS

A systematic search on Medline, PubMed, EMBASE and Google Scholar databases was conducted to identify papers that reported gender-specific waist circumference (WC) estimates of participants from the age of 15 years and above among Aboriginal and non-Aboriginal Australians. Means and their 95% confidence intervals of gender differences in WC, height and weight were recorded or calculated where they were not provided. Gender-specific WC, height and weight mean estimates were pooled and the I(2) statistic was used to test heterogeneity among Aboriginal and non-Aboriginal Australians.

RESULTS

Of 17 selected cross-sectional studies, 9 focused on Aboriginal and 8 on non-Aboriginal Australians. Seven studies reported significantly higher WC estimates among indigenous females than males. On the other hand, non-indigenous males had significantly higher WC levels than females. Males had greater height and weight estimates than females in both groups.

CONCLUSION

Although indigenous women were shorter and had lower weight estimates, they had greater WC levels than indigenous men. This is the first systematic review to assess the gender-specific differences between Aboriginal and non-Aboriginal Australians. The findings of this review warrant more efforts to understand and reduce the high prevalence of central obesity and related chronic diseases among Aboriginal women.

Similarities and differences in cardiometabolic risk factors among remote Aboriginal Australian and Canadian cohorts

AIM

Indigenous populations of Australia and Canada experience disproportionately high rates of chronic disease. We hypothesized that despite the common outcome of increased diabetes prevalence, differences in cardiometabolic risk profile may exist between these populations.

METHODS

We compared community-based data on cardiometabolic risks in Aboriginal Australians (n=297 without, 45 with diabetes), and Aboriginal Canadians (n=409 without, 87 with diabetes).

RESULTS

Despite strikingly lower weight (62 vs 83 kg, p<0.0001) and body mass index (BMI, 22 vs 29 kg/m(2), p<0.0001), Aboriginal Australians without diabetes had similar waist-hip ratio (WHR, 0.91 vs 0.91, p=0.732), lower HDL-cholesterol (0.97 vs 1.25 mmol/L, p<0.0001) and higher HbA1c (5.4 vs 5.2%, p<0.0001) than Aboriginal Canadians without diabetes. Waist was the obesity measure most strongly related to diabetes or cardiometabolic risk in Australians while BMI performed similarly to other obesity measures only in Canadians. Multiple regression of HbA1c revealed age and fasting glucose as independent predictors in each study group, with the addition of WHR in Aboriginal Australians.

CONCLUSION

The notable finding was that waist or WHR are preferred obesity measures to appropriately reflect cardiometabolic risk in Aboriginal Australians, who although leaner by BMI criteria, displayed a similarly adverse risk profile to Aboriginal Canadians. Waist or WHR should be routinely included in clinical assessment in these high-risk populations.

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

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

Association of ADIPOQ +45T>G polymorphism with body fat mass and blood levels of soluble adiponectin and inflammation markers in a Mexican-Mestizo population

PURPOSE

Obesity is a disease with genetic susceptibility characterized by an increase in storage and irregular distribution of body fat. In obese patients, the decrease in the Adiponectin gene (ADIPOQ) expression has been associated with a systemic low-grade inflammatory state. Our aim was to investigate the relationship between ADIPOQ +45T>G gene simple nucleotide polymorphism (SNP rs2241766) with serum adiponectin (sAdiponectin), distribution of body fat storage, and inflammation markers.

SUBJECTS AND METHODS

In this cross-sectional study, 242 individuals from Western Mexico characterized as Mexican-Mestizo and classified by body mass index (BMI), were included. Anthropometrics, body composition, body fat distribution, and inflammation markers were measured by routine methods. Genotypes were characterized using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique and sAdiponectin by the ELISA method. A P-value <0.05 was considered the statistically significant threshold.

RESULTS

sAdiponectin is associated with BMI (P < 0.001) and the genotypes (P < 0.001 to 0.0046) GG (8169 ± 1162 ng/mL), TG (5189 ± 501 ng/mL), and TT (3741 ± 323 ng/mL), but the SNP ADIPOQ +45T>G is not associated with BMI. However, the detailed analysis showed association of this SNP with a pattern of fat distribution and correlations (P < 0.05) with inflammation markers and distribution of body fat storage (Pearson's r = -0.169 to -0.465) were found.

CONCLUSION

In this study, we have suggested that the ADIPOQ +45G allele could be associated with distribution of body fat storage in obesity. On the other hand, as no association was observed between ADIPOQ +45T>G gene polymorphism and obesity, it cannot be concluded that the ADIPOQ +45G allele is responsible for the increase of adiponectin levels.