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Summary Objective Although elevated body mass index (BMI) and waist circumference (WC) have been identified as risk factors for mortality, data from the Australian Aboriginal communities are scarce. This study examined the associations of BMI and WC with all-cause mortality in an Australian Aboriginal community. Methods A total of 934 Aboriginal adults, aged 18–76 years, who participated in a community-wide screening programme in Australia's Northern Territory from 1992 to 1998, were followed-up prospectively for up to 18 years for death outcomes. The hazard ratios for mortality were estimated by baseline BMI and WC. Age, sex, smoking and alcohol consumption status were adjusted for in multivariable analysis. Results In 14,750 person-years of follow-up, 216 deaths were recorded. For each standard deviation increase in BMI, the risk of all-cause death decreased by 9% (95% CI: 0.80–1.05); whereas for each SD increase in WC, the risk of all-cause mortality increased by 17% (95% CI: 1.03–1.33). The risk of mortality was lower in the 3rd BMI tertile compared to the 1st tertile for mortality after adjusting for WC, age, sex, smoking and alcohol consumption. Risk of death was higher in WC tertile 3 compared to tertile 1 after adjusting for BMI, age, sex, smoking and alcohol consumption. Conclusions The risk of all-cause mortality among participants increased with higher WC, while participants with relatively higher BMI had a lower mortality risk. WC had stronger association with mortality than did BMI. The results indicate the importance of assessing WC measures in studies conducted in Aboriginal Australia. [ABSTRACT FROM AUTHOR]

The article discusses research on patterns of mortality in Indigenous adults in the Australian Northern Territory between 1998 and 2003. The Australian Bureau of Statistics mortality data were used in the study. The data revealed that Indigenous mortality was up to nine times higher in remote areas, three times higher in outer regional areas, and two times higher in very remote areas when compared to the mortality in the general Australian population.

Evaluates the rates and associations of the renal disease underlying an epidemic of renal failure among Aboriginal people in a remote location in the Northern Territory of Australia. Detection of renal disease; Multideterminant nature of most other causes of excess mortality in Aboriginal people; Health status of Aborigines in the Northern Territory.

Two letters to the editor are presented in response to the article "Patterns of Mortality in Indigenous Adults in the Northern Territory, 1988-2003," by Karen Andreasyan and Wendy Hoy, published in the May 2009 issue.

The article discusses a study on the incidence of mental disorders due to substance abuse and cardiovascular disease (CVD) among Aboriginal adults in a remote Indigenous community in the Australian Northern Territory. A population-based renal disease screening program has been performed during the research period between 1992 and 1995. After the adjustment of potential confounders the study confirmed the link between CVD and substance use-related mental disorders in the population concerned.

Background: Indigenous Australians are significantly burdened by chronic kidney disease (CKD). Elevated levels of C-reactive protein (CRP) have been associated with diabetes and cardiovascular incidence in previous studies. Elevated CRP has been associated with albuminuria and reduced eGFR in cross-sectional studies. This study investigated the long-term predictive association between CRP measured at a baseline exam and the incidence of a CKD-related hospitalization., Methods: Health screening examinations were conducted in individuals of a remote indigenous Australian community between 1992 and 1998. The risk of subsequent CKD hospitalisations, documented through Northern Territory hospital records up to 2010, was estimated with Cox proportional hazard models in people aged over 18 years at the baseline screen and who had albumin-creatinine ratios (ACRs) less than 34g/mol., Results: 546 participants were eligible for our study. Individuals in the highest CRP tertile at baseline had increased levels of traditional cardiovascular risk factors. They also had almost 4 times the risk of a CKD-related hospitalisation compared with participants in the lowest CRP tertile (HR=3.91, 95%CI 1.01-15.20, P=0.049) after adjustment for potential confounding factors. Participants with CRP concentrations greater than 3mg/L had almost 3 times the risk of CKD hospitalisations than those ≤3mg/L (HR=2.84, 95%CI 1.00-8.00, P=0.049). Furthermore, risk of CKD hospitalisations increased 34% per doubling of baseline CRP (HR=1.34, 95%CI 1.04-1.74, P=0.024)., Conclusion: In individuals in this remote indigenous community without overt albuminuria at baseline the risk for incident CKD related hospitalisations was predicted by elevated C-reactive protein levels almost a decade earlier. Further research is needed to understand the roles that CRP and systemic inflammation play in CKD risk., (© 2016 Asian Pacific Society of Nephrology.)

Objective: To examine the trends of all-cause natural mortality for people aged 15 years and over in a remote Australian Aboriginal community between 1996 and 2010., Methods: The annual population in the community by gender and age group was obtained from the Australian Bureau of Statistics (ABS). All known deaths and all records of start of renal replacement therapy (RRT) for renal failure were recorded between 1996 and 2010. Five-year aggregated death rates were calculated and the changes in natural mortality over the interval were evaluated. Mortality was compared with those of the Northern Territory (NT) Indigenous and non-Indigenous people as a whole from 1998 to 2006., Results: Rates of natural deaths were lower in the third interval 2006-2010 relative to the first interval 1996-2000, with higher, but more rapidly falling rates for females than males. Reductions were prominent for both sexes in the 65 and over age groups, but death rates in females of earlier middle age also trended lower. The trends applied whether or not the starting of RRT was considered as a natural death. There was a similar trend in rates of natural death in the aggregate Indigenous population of NT., Conclusions: The downward trends probably reflect improvements in risk factor status since the 1960s, all-of-life health interventions, as well as better chronic disease management in the last two decades. The higher death rates in females than males in this community remain unexplained, but the rapid rate of decline of female death rates predicts that this gap will soon be minimised., (© 2013 The Authors. ANZJPH © 2013 Public Health Association of Australia.)

Background: Diabetes is an important contributor to the health inequity between Aboriginal and non-Aboriginal Australians. This study aims to estimate incidence rates of diabetes and to assess its associations with impaired fasting glucose (IFG) and impaired glucose tolerance (IGT) among Aboriginal participants in a remote community., Methods: Six hundred and eighty six (686) Aboriginal Australians aged 20 to 74 years free from diabetes at baseline were followed for a median of 11 years. During the follow-up period, new diabetes cases were identified through hospital records. Cox proportional hazards models were used to assess relationships of the incidence rates of diabetes with IFG, IGT and body mass index (BMI)., Results: One hundred and twenty four (124) new diabetes cases were diagnosed during the follow up period. Incidence rates increased with increasing age, from 2.2 per 1000 person-years for those younger than 25 years to 39.9 per 1000 person-years for those 45-54 years. By age of 60 years, cumulative incidence rates were 49% for Aboriginal men and 70% for Aboriginal women. The rate ratio for developing diabetes in the presence of either IFG or IGT at baseline was 2.2 (95% CI: 1.5, 3.3), adjusting for age, sex and BMI. Rate ratios for developing diabetes were 2.2 (95% CI: 1.4, 3.5) for people who were overweight and 4.7 (95% CI: 3.0, 7.4) for people who were obese at baseline, with adjustment of age, sex and the presence of IFG/IGT., Conclusions: Diabetes incidence rates are high in Aboriginal people. The lifetime risk of developing diabetes among Aboriginal men is one in two, and among Aboriginal women is two in three. Baseline IFG, IGT and obesity are important predictors of diabetes.

Objective: To investigate the association between C-reactive protein (CRP) and the risk of developing diabetes in Aboriginal Australians., Research Design and Methods: High sensitivity CRP levels were measured in 620 Aboriginal participants aged 20-74 years free from diabetes at baseline in a remote community in the Northern Territory of Australia. Participants were followed for a median of 11 years to identify newly diagnosed cases of diabetes. Cox proportional hazards models were used to assess the relationship of CRP levels with the risk of developing diabetes over the follow-up period., Results: A total of 109 participants were newly diagnosed with diabetes. Incident rates were 10.8, 16.6 and 28.8 per 1000 person-years for people in the lower, middle and upper tertile groups of baseline CRP levels, respectively. After adjusting for age, sex, BMI, baseline glucose regulation status, total cholesterol, urine albumin to creatinine ratio, systolic blood pressure, smoking and alcohol drinking, the association between diabetes and CRP remained significant, with a hazard ratio of 1.23 (95% confidence interval (CI) 1.05, 1.45) corresponding to a doubling in CRP values. Similarly, the adjusted hazard ratio for development of diabetes in people in the upper tertile versus the bottom two tertiles of CRP was 1.75 (95% CI 1.19, 2.56)., Conclusions: CRP is independently associated with the development of diabetes in Aboriginal people. Our findings support a role of inflammation in the etiology of diabetes in the high risk population of Aboriginal Australians.

Background: Aboriginal Australians experience a higher risk of diabetes than the general Australian population. In this paper, we conducted a nested case-control study to determine whether the presence of microalbuminuria and macroalbuminuria is associated with the development of diabetes among diabetes-free Aboriginal people at baseline., Methods: Urine albumin to creatinine ratios (ACRs) were obtained from 882 Aboriginal people aged 20-74 years from one community. Among them 750 were free of either clinical known diabetes or newly diagnosed diabetes according to WHO 1999 criteria. Over an 11 year follow-up period, 117 participants developed diabetes. They were defined as cases. Each case was matched by an individual control with same sex and body mass index (BMI) category, and age within 2 years. Conditional logistic regression was used to assess the association between albuminuria and diabetes., Results: The baseline level of ACR was significantly higher among cases than among controls. The odds ratios for future diabetes were 2.36 [95% confidence interval (95% CI) 1.01-5.50] and 3.27 (95% CI 1.38-7.77) for middle and upper tertiles, respectively, with adjustment for age, BMI, serum total cholesterol, serum C-reactive protein values, and fasting plasma glucose at the baseline. The adjusted odds ratios were 1.90 (95% CI 0.88-4.06) and 2.51 (95% CI 1.08-5.87) for those with microalbuminuria and macroalbuminuria, respectively., Conclusions: The presence of microalbuminuria and macroalbuminuria predicts diabetes independent of other known risk markers of development of type 2 diabetes in Aboriginal people.

Objectives: To describe the association between renal disease and other features of the metabolic syndrome and its derivative illnesses among Australian Aborigines in remote settings., Methods: Volunteering adults (N = 2019) in four remote communities were screened for risk factors and markers of renal disease, hypertension, and diabetes, and their cross-sectional associations were evaluated. Rates of the metabolic syndrome were estimated in one community with comprehensive screening data. The associations of albuminuria with hospitalizations, coronary heart events, and non-renal deaths were then followed for > 7 years in that same community., Results: Rates of renal disease, hypertension, and diabetes all increased dramatically with age. They all overlapped. Renal disease and hypertension were the most prominent and earliest features of the syndrome, while diabetes was a later, less common and more variable manifestation. All were strongly correlated with waist measurements, and high waist measurements more comprehensively characterized those with illnesses than did the more restrictive definitions of the metabolic syndrome. Albuminuria predicted non-renal hospitalizations, first time coronary heart disease events, and all-cause death., Conclusion: Albuminuria/proteinuria is an early and dominant element of a symptom complex that is marked by higher waist measurements, and it strongly predicts all-cause and cardiovascular illnesses and deaths. This finding implies a common background of risk factors for renal disease, hypertension, diabetes, and cardiovascular risk. The findings support integrated, rather than disease-specific, surveillance programs, an important role for albuminuria in predicting non-renal risk, and a unified approach for primary and secondary prevention of all elements of the syndrome.

Background: It has been suggested that albuminuria is useful in identifying persons at increased risk of coronary heart disease (CHD). Australian Aborigines have exceedingly high rates of renal failure together with increased CHD mortality. We undertook this prospective cohort study to assess the independent effect of albuminuria on CHD risk in Aboriginal people in the Northern Territory of Australia., Methods: We examined the relation between micro- and macroalbuminuria and incident CHD in a sample of 870 Aboriginal adults aged 20 to 74 years old without prevalent baseline CHD. Cox proportional hazards models were used to assess the association between baseline albuminuria and CHD incidence., Results: During a median of 9.2 years of follow-up, 89 CHD events occurred during the follow-up period (1992 to 2003). The incidence of CHD increased significantly across categories of albuminuria (4.4, 10.9, and 29.8 per 1000 person-years for normoalbuminuria, microalbuminuria, and macroalbuminuria, respectively). The multiple Cox proportional hazards regression showed the hazard ratio was 3.4 (95% CI 1.6, 7.3), adjusting for age, gender, body mass index (BMI), blood pressure, total cholesterol, diabetes status, cigarette smoking, and alcohol consumption, for macroalbuminuria group. Hazard ratio for microalbuminuria group was not significantly different from unity during the first 6 years of follow-up but significantly higher during the follow-up period > or = 6 years with adjusted hazard ratio 9.0 (95% CI 2.0, 40.0)., Conclusion: Independent of traditional cardiovascular risk factors, both microalbuminuria and macroalbuminuria may be useful in identifying persons at increased risk of CHD in Aboriginal people.

Objective: To determine the extent to which the Framingham function predicts the risk of coronary heart disease (CHD) in Aboriginal people., Design and Setting: Cohort study in an Aboriginal community in the Northern Territory., Participants: 687 Aboriginal people aged 20-74 years were followed up from a baseline examination in 1992-1995 through to 31 December 2003., Main Outcome Measure: First CHD events were identified through hospital and death records during the follow-up period., Methods: An original Framingham function was used to predict CHD risk according to the duration of follow-up and the values of traditional risk factors, which included age, sex, total cholesterol level, high-density lipoprotein (HDL) cholesterol level, blood pressure, the presence of diabetes, and smoking status. The predicted CHD incidence using the Framingham function was 4.4 per 1000 person-years, while the observed incidence was 11.0 (95% CI, 8.7-13.9) per 1000 person-years. The observed number of CHD events (68) was 2.5 times the number predicted (27) using the Framingham function. The observed incidence was about four and three times the predicted incidence for age groups < 35 and 35-44 years, respectively, and about twice the predicted incidence for those over 45 years of age. The Framingham function was a particularly unreliable predictor for women, especially younger women, in whom the observed CHD rate was 30 times the predicted rate., Conclusions: The Framingham function substantially underestimates the actual risk of CHD observed in Aboriginal people in a remote community, especially for women and younger adults. This implies that traditional risk factors have different degrees of impact and/or that other factors are contributing to risk. A population-specific risk function is needed.

Background: Rates of cardiovascular disease and renal disease in Australian Aboriginal communities are high, as is the prevalence of some 'traditional' cardiovascular (CV) risk factors, such as diabetes and cigarette smoking. Recent work has highlighted the importance of markers of inflammation, such as C-reactive protein (CRP), homocysteine and albuminuria as predictors of cardiovascular risk in urban westernized settings. It is not clear how these factors relate to outcome in the setting of these remote communities, but very high CRP concentrations have been shown in this and other Aboriginal communities., Methods and Results: In a cross-sectional survey including 237 adults in a remote Aboriginal community in the Northern Territory of Australia, we measured carotid intima-media thickness (IMT), together with blood pressure, diabetes, lipid levels, smoking and albuminuria, CRP and fibrinogen, serum homocysteine concentration, and IgG titres for Chlamydia pneumoniae, Helicobacter pylori and cytomegalovirus. Median carotid IMT was 0.63 [interquartile range 0.54-0.71] mm. As a categorical outcome, the prevalence of the highest IMT quartile ('increased IMT', > or =0.72 mm) was compared with the lower three quartiles. Increased IMT was associated in univariate analyses with greater waist circumference, systolic BP, fibrinogen and serum albumin concentrations, urine albumin/creatinine ratio and older age as continuous variables. Associations of increased IMT with some continuous variables were not linear; univariate associations were seen with the highest quartile (versus all other quartiles) of CRP and homocysteine concentration and CMV IgG titre. In a multivariate model age, smoking, waist circumference and the highest quartile of CRP concentrations (> or =14 mg/l) remained significant predictors of IMT > or =0.72 mm., Conclusions: Measurement of carotid IMT was possible in this remote setting. Increased IMT (> or =0.72 mm) was associated with increased CRP concentrations over a range that suggests infection/inflammation may be important determinants of cardiovascular risk in this setting. The associations of IMT with markers of renal disease seen in univariate analyses were explained in this analysis by confounding due to the associations of urine ACR with other risk factors.

Objectives: To determine the incidence rate of coronary heart disease (CHD) in Australian Aboriginal people with type 2 diabetes, and to compare the impact of diabetes on CHD risk in Aboriginal women and men., Design: Cohort study., Setting: A remote Aboriginal community in the Northern Territory., Participants: 889 Aboriginal people aged 20-74 years followed up to 31 May 2003 after baseline examination in 1992-1995., Main Outcome Measures: Incidence rates of CHD (estimated for 123 participants with diabetes at baseline and 701 "non-diabetes" participants); rate ratios for diabetes risk (95% CI), with "non-diabetes" participants as the reference group., Results: Participants with diabetes at baseline had a higher rate of CHD (37.5 per 1000 person-years) than those without diabetes (7.3 per 1000 person-years). Adjustment for multiple CHD risk factors, such as age, smoking, alcohol consumption, systolic blood pressure, body mass index, high-density lipoprotein cholesterol and total cholesterol levels, resulted in a CHD rate ratio for women of 3.7 (95% CI, 1.6-8.9) (comparing women with diabetes with those without) and a CHD rate ratio for men of 1.4 (95% CI, 0.4-4.1) (comparing men with diabetes with those without)., Conclusions: Aboriginal women with diabetes experienced a significantly higher risk of CHD than women without diabetes. Although the difference was not statistically significant, women with diabetes had a higher CHD risk than men with diabetes.

Objectives: To study the relationship of blood pressure to birthweight and current body mass index in a population with high rates of low birthweight (< 2.5 kg)., Design: A cross-sectional population screening program conducted between 1992 and 1998, with retrospective retrieval of birthweights., Setting: A remote coastal Australian Aboriginal community with a high prevalence of diabetes, cardiovascular and renal disease., Participants: Eighty-two per cent of the community members (1473/1805) were screened. Birthweights were available for 767 (71%) of the screened participants aged 7-43 years., Main Outcome Measures: The association between birthweight and current blood pressure, accounting for current body mass index., Results: Mean birthweights were low, and 18% of children and 35% of adults had been low-birthweight babies. In children (7-17 years), blood pressure was not correlated with birthweight, but in adults there was an inverse correlation - a 1 kg increase in birthweight was associated with a 2.9 mmHg (95% CI, 0.3-5.5 mmHg) decrease in systolic blood pressure, after adjusting for age, sex and current weight. Overweight adults with low birthweight had the highest blood pressures., Conclusions: Low birthweight is significantly associated with higher blood pressure in adult life, and the effect is amplified by higher current weight. Given the high rates of low birthweight in Aboriginal people in remote areas, and the detrimental effect of higher blood pressures on chronic diseases (currently present in epidemic proportions), interventions should focus on improving birthweights and on weight control in adolescents and adults. Special attention should be paid to children with low birthweight to avoid their becoming overweight in adult life.

Background: Australian Aborigines living in remote areas have exceedingly high rates of renal failure together with increased cardiovascular morbidity and mortality. To examine the basis of this association, we studied markers of renal function and cardiovascular (CV) risk in a coastal Aboriginal community in a remote area of the Northern Territory of Australia. End-stage renal disease (ESRD) incidence rates in that community are 15 times the national non-Aboriginal rate and CV mortality rates in the region are increased 5-fold., Methods: A cross-sectional community survey was conducted. Markers of early renal disease examined included urine albumin/creatinine ratio (ACR), serum creatinine concentration and calculated glomerular filtration rate (GFR). CV risk markers included blood pressure as well as measures of glycaemia, diabetes and serum lipids., Results: The study group included 237 people, 58% of the adult population of the community. The crude prevalence of microalbuminuria (urine ACR: 3.4-33.9 g/mol, 30-299 mg/g) was 31% and of overt albuminuria (urine ACR: >or=34 g/mol, >or=300 mg/g), 13%. The prevalence of overt albuminuria increased with age, but the prevalence of microalbuminuria was greatest in the 45-54 year age group. Microalbuminuria was associated with increasing body mass index, whereas overt albuminuria was associated with increasing glycated haemoglobin (HbA1c) and systolic blood pressure and a history of diabetes. The prevalence of elevated serum creatinine concentration (>or=120 micromol/l) was 10%. GFR (calculated using the MDRD equation) was <60 ml/min/1.73 m(2) in 12% and 60-79 ml/min/1.73 m(2) in a further 36% of the study population. Although many people with albuminuria had well preserved GFRs, mean GFR was lower in people with higher levels of albuminuria., Conclusions: The high prevalence of markers of renal disease in this community was consistent with their high rates of ESRD. The distribution of microalbuminuria suggested a 'cohort effect', representing a group who will progress to overt albuminuria. The powerful association of renal disease markers with CV risk factors confirms a strong link between renal and CV disease in the early, asymptomatic stages of each. Thus, pathologic albuminuria, in part, might be a manifestation of the metabolic/haemodynamic syndrome and both conditions might arise out of a common menu of risk factors. Hence, a single agenda of primary and secondary intervention may benefit both.

Objective: To examine the relationship between self-reported tobacco smoking and urinary cotinine concentrations in the setting of a remote Aboriginal community., Methods: In a remote Northern Territory (NT) Aboriginal community the relationship between self-reported tobacco smoking and urinary cotinine concentrations was examined as part of a cross-sectional survey of cardiovascular risk factors. Current tobacco smoking was assessed as part of a questionnaire. The concentration of cotinine and cotinine/creatinine ratio (CCR) in a spot urine sample were used as a biochemical marker of nicotine exposure., Results: A total of 237 people took part in the survey, although completed questionnaires and urine results were available for 184 people. Current tobacco smoking was reported by 161 (69 [95% CI 63 to 75]%) people, with higher rates among males (84/104, 81 [95% CI 72 to 88]%) than females (77/129, 60 [95% CI 51 to 68]%, p < 0.001). There was good agreement of self report with current tobacco smoking using categories based on urinary cotinine (agreement 94%, kappa = 0.84) and urinary CCR (agreement 94%, kappa = 0.86). Quantitative agreement between cotinine measures and self-reported number of cigarettes per day was better for CCR than cotinine, but the correlation was relatively weak for both., Conclusions: Self-reported cigarette smoking is a valid qualitative measure in this environment. The relatively weak correlation between the biomarker and number of reported cigarettes smoked illustrates problems both with questionnaire and urinary markers of nicotine exposure., Implications: As a qualitative measure of tobacco smoking in this setting, self-report appears adequate but the validity of quantitative self-report is unclear.

Objective: To assess the association between body mass index and the risk of all-cause and disease-specific mortalities in Australian Aborigines in a remote community., Design: A community based cohort study., Participants and Setting: 744 Aboriginal adults aged 20 to 77 years in a remote community in Northern Territory. Eighty-seven deaths occurred during the follow-up period of 5,040.8 person-years., Measures: Mortality data for the period of 1992 and June 2000 were collected. Mortality rate ratios for each body mass index quartile was determined using a Cox proportional hazards model with adjustment for age, sex, and smoking and drinking status., Results: An inverse relationship between BMI quartiles and the risk of all-cause, natural, and non-CVD mortality was found. Adjusted rate ratios (95% CI) of all-cause mortality were 0.92 (0.54-1.59), 0.71 (0.40-1.26) and 0.38 (0.19-0.75) for second, third and fourth BMI quartiles, respectively, with the first quartile as the reference. The fourth BMI quartile had the lowest risk of mortality with adjusted rate ratios of 0.38, 0.28, and 0.16 for deaths from all-cause, natural, and non-CVD, respectively. However, the associations between BMI and CVD and renal deaths did not reach statistical significance., Conclusions: BMI and mortality are inversely associated in Aboriginal adults in a remote community. Individuals with relatively higher BMI have a lower risk of death.