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Objective: The aim of this work was to study the frequency of examining for diabetic eye and foot complications in an Australian population and to study factors associated with regular screening.Research Design and Methods: The Australian Diabetes, Obesity, and Lifestyle Study (AusDiab) was a population-based study of 11,247 people from randomly selected areas of Australia. Participants identified as having previously diagnosed diabetes (n=475) were invited to participate in the complications study. Measures included foot examination, retinopathy photography, and self-report use of health care services.Results: Seventy-seven percent of participants reported having an eye examination within the previous 2 years, and 50% reported having their feet examined by a health professional in the previous year. Type of diabetes treatment (odds ratio 1.46, 95% CI 0.85-2.50 for tablets versus diet alone and 4.17, 1.71-10.17 for insulin or insulin and tablets versus diet alone) and visiting a diabetes nurse educator in the previous 12 months (2.14, 1.18-3.87) were independent predictors of having had an eye examination. Duration of diabetes (1.33, 1.06-1.67 per year) and visiting a diabetes nurse educator in the previous 12 months (1.89, 1.20-2.95) were independent predictors of a foot examination.Conclusions: This study has shown that retinopathy screening is performed more frequently than foot screening in Australia. This may be due to the implementation of eye screening programs and awareness campaigns. Foot screening appears to be poor, with less than one-half of the population reporting a regular examination for foot complications. In Australia, diabetes nurse educators play a key role in promoting screening for diabetes complications. [ABSTRACT FROM AUTHOR]

Discusses macrovascular diabetic disease. The risk of cardiovascular disease (CVD) for people with non-insulin-dependent diabetes mellitus (NIDDM); Population studies of CVD in NIDDM; Possibility of a thrifty genotype that conveys NIDDM and CVD risk.

Two major reports have recently revised the classification of and diagnostic criteria for diabetes. Classification was previously based on the need for insulin (insulin-dependent or non-insulin-dependent), but this has become increasingly confusing. Now, the type of diabetes is determined by the etiological process rather than the treatment modality. Type 1 diabetes is thus characterized by islet cell destruction and type 2 diabetes by a combination of defects in insulin secretion and action. An individual with either type of diabetes may be on any treatment modality: This classification should prove to be more logical and, for example, allow latent autoimmune diabetes in adults, which typically does not require insulin at presentation, to be classified as type 1 diabetes. The fasting plasma glucose diagnostic threshold for diabetes has been lowered to 7.0 mmol/l (126 mg/dl), and impaired fasting glucose (fasting plasma glucose 6.1-6.9 mmol/l [ 110-125 mg/dl]) has been introduced as a new category of intermediate glucose metabolism. These changes recognize that the old fasting threshold did not match the 2-h (postload) threshold well and that both micro- and macrovascular disease develop at lower fasting glucose levels than previously recognized. Although the prevalences of diabetes according to the new fasting and 2-h criteria are now similar in most populations, the actual individuals identified as having diabetes are often different. Over 30% of all those with diabetes have a nondiabetic fasting glucose but still have increased cardiovascular mortality: Thus, it is important to retain the oral glucose tolerance test for the diagnosis of diabetes. [ABSTRACT FROM AUTHOR]

Objective: To examine the role of area-level socioeconomic status (SES) on the development of abnormal glucose metabolism (AGM) using national, population-based data.Research Design and Methods: The Australian Diabetes, Obesity and Lifestyle (AusDiab) study is a national, population-based, longitudinal study of adults aged ≥25 years. A sample of 4,572 people provided complete baseline (1999 to 2000) and 5-year follow-up (2004 to 2005) data relevant for these analyses. Incident AGM was assessed using fasting plasma glucose and 2-h plasma glucose from oral glucose tolerance tests, and demographic, socioeconomic, and behavioral data were collected by interview and questionnaire. Area SES was defined using the Index of Relative Socioeconomic Disadvantage. Generalized linear mixed models were used to examine the relationship between area SES and incident AGM, with adjustment for covariates and correction for cluster design effects.Results: Area SES predicted the development of AGM, after adjustment for age, sex, and individual SES. People living in areas with the most disadvantage were significantly more likely to develop AGM, compared with those living in the least deprived areas (odds ratio 1.53; 95% CI 1.07-2.18). Health behaviors (in particular, physical activity) and central adiposity appeared to partially mediate this relationship.Conclusions: Our findings suggest that characteristics of the physical, social, and economic aspects of local areas influence diabetes risk. Future research should focus on identifying the aspects of local environment that are associated with diabetes risk and how they might be modified. [ABSTRACT FROM AUTHOR]

Over the past three decades, the number of people with diabetes mellitus has more than doubled globally, making it one of the most important public health challenges to all nations. Type 2 diabetes mellitus (T2DM) and prediabetes are increasingly observed among children, adolescents and younger adults. The causes of the epidemic of T2DM are embedded in a very complex group of genetic and epigenetic systems interacting within an equally complex societal framework that determines behavior and environmental influences. This complexity is reflected in the diverse topics discussed in this Review. In the past few years considerable emphasis has been placed on the effect of the intrauterine environment in the epidemic of T2DM, particularly in the early onset of T2DM and obesity. Prevention of T2DM is a 'whole-of-life' task and requires an integrated approach operating from the origin of the disease. Future research is necessary to better understand the potential role of remaining factors, such as genetic predisposition and maternal environment, to help shape prevention programs. The potential effect on global diabetes surveillance of using HbA(1c) rather than glucose values in the diagnosis of T2DM is also discussed. [ABSTRACT FROM AUTHOR]

Abstract. Hare MJL, Shaw JE, Zimmet PZ (Baker IDI Heart and Diabetes Institute, Melbourne, Vic.; and Monash University, Melbourne, Vic.; Australia). Current controversies in the use of haemoglobin A(1c) (Review). J Intern Med 2012; 271: 227-236. Haemoglobin A(1c) (HbA(1c) ) has recently been adopted by the World Health Organization into its recommended criteria for diabetes diagnosis. Much debate continues regarding the relative benefits and potential disadvantages surrounding the use of HbA(1c) for this purpose. There is a lack of consensus as to whether this alteration to the definition of diabetes is a step forward or whether it could add further confusion and ambiguity to the debate on the method and criteria for the diagnosis of this globally important disease. This review provides a comprehensive overview of the current issues surrounding how HbA(1c) is measured and reported; and of the evidence for and against its use in diagnosis. [ABSTRACT FROM AUTHOR]

Objective: Little information is available on the impact of abnormal glucose tolerance on mortality in South Asian and African populations in the developing world. We explored this issue in a large, multiethnic cohort from the developing nation of Mauritius.Research Design and Methods: Population-based surveys were undertaken in 1987, 1992, and 1998. The 9,559 participants (20-82 years old) comprised 66% South Asian (Indian), 27% Creole (African), and 7% Chinese descent. Mortality was ascertained in 2007.Results: Over a median 15.1-year follow-up, 1,557 participants died. Compared with those with normal glucose tolerance, the all-cause mortality hazard ratios (HR) for known diabetes, newly diagnosed diabetes, and impaired glucose tolerance were 3.35 (95% CI 2.77-4.04), 2.11 (1.73-2.57), and 1.53 (1.26-1.87) in South Asians and 2.14 (1.65-2.79), 1.41 (1.06-1.88), and 1.08 (0.83-1.40) in Africans, respectively. Those with impaired fasting glucose were not at increased risk in either ethnicity. In the Chinese, only those with known diabetes were at increased risk of mortality with HR 3.68 (1.87-7.25).Conclusions: This is the first study in a developing country of the impact of glucose intolerance on mortality in an African population, and one of the first studies of a South Asian population. It shows that the impact on mortality in these populations in Mauritius is comparable to that seen in developed countries. These results are important in a global context for future health policy in light of the impact of the rapid increase in prevalence of diabetes, especially in developing nations. [ABSTRACT FROM AUTHOR]

OBJECTIVE: This national, population-based study reports diabetes incidence based on oral glucose tolerance tests (OGTTs) and identifies risk factors for diabetes in Australians. RESEARCH DESIGN AND METHODS: The Australian Diabetes, Obesity and Lifestyle Study followed-up 5,842 participants over 5 years. Normal glycemia, impaired fasting glucose (IFG), impaired glucose tolerance (IGT), and diabetes were defined using World Health Organization criteria. RESULTS: Age-standardized annual incidence of diabetes for men and women was 0.8% (95% CI 0.6-0.9) and 0.7% (0.5-0.8), respectively. The annual incidence was 0.2% (0.2-0.3), 2.6% (1.8-3.4), and 3.5% (2.9-4.2) among those with normal glycemia, IFG, and IGT, respectively, at baseline. Among those with IFG, the incidence was significantly higher in women (4.0 vs. 2.0%), while among those with IGT, it was significantly higher in men (4.4 vs. 2.9%). Using multivariate logistic regression, hypertension (odds ratio 1.64 [95% CI 1.17-2.28]), hypertriglyceridemia (1.46 [1.05-2.02]), log fasting plasma glucose (odds ratio per 1 SD 5.25 [95% CI 3.98-6.92]), waist circumference (1.26 [1.08-1.48]), smoking (1.70 [96% CI 1.11-2.63]), physical inactivity (1.56 [1.12-2.16]), family history of diabetes (1.82 [1.30-2.52]), and low education level (1.85 [1.04-3.31]) were associated with incident diabetes. In age- and sex-adjusted models, A1C was a predictor of diabetes in the whole population, in those with normal glycemia, and in those with IGT or IFG. CONCLUSIONS: Diabetes incidence is 10-20 times greater in those with IGT or IFG than those with normal glycemia. Measures of glycemia, A1C, metabolic syndrome components, education level, smoking, and physical inactivity are risk factors for diabetes. [ABSTRACT FROM AUTHOR]

Objectives: To compare body mass index (BMI), waist circumference and waist-hip ratio (WHR) as indices of obesity and assess the respective associations with type 2 diabetes, hypertension and dyslipidaemia.Design and Setting: A national sample of 11 247 Australians aged > or =25 years was examined in 2000 in a cross-sectional survey.Main Outcome Measures: The examination included a fasting blood sample, standard 2-h 75-g oral glucose tolerance test, blood pressure measurements and questionnaires to assess treatment for dyslipidaemia and hypertension. BMI, waist circumference and WHR were measured to assess overweight and obesity.Results: The prevalence of obesity amongst Australian adults defined by BMI, waist circumference and WHR was 20.8, 30.5 and 15.8% respectively. The unadjusted odds ratio for the fourth vs. first quartile of each obesity measurement showed that WHR had the strongest relationship with type 2 diabetes, dyslipidaemia (women only) and hypertension. Following adjustment for age, however, there was little difference between the three measures of obesity, with the possible exceptions of hypertension in women, where BMI had a stronger association, and dyslipidaemia in women and type 2 diabetes in men, where WHR was marginally superior.Conclusions: Waist circumference, BMI and WHR identified different proportions of the population, as measured by both prevalence of obesity and cardiovascular disease (CVD) risk factors. Whilst WHR had the strongest correlations with CVD risk factors before adjustment for age, the three obesity measures performed similarly after adjustment for age. Given the difficulty of using age-adjusted associations in the clinical setting, these results suggest that given appropriate cut-off points, WHR is the most useful measure of obesity to use to identify individuals with CVD risk factors. [ABSTRACT FROM AUTHOR]

Objective: To investigate pedometer-measured physical activity (PA) in 2000 and change in PA over 5 years with subsequent risk of dysglycemia by 2005.Research Design and Methods: This prospective cohort study in Tasmania, Australia, analyzed 458 adults with normal glucose tolerance and a mean (SD) age of 49.7 (12.1) years in 2000. Variables assessed in 2000 and 2005 included PA, by pedometer and questionnaire, nutrient intake, and other lifestyle factors. Incident dysglycemia was defined as the development of impaired fasting glucose or impaired glucose tolerance revealed by oral glucose tolerance testing in 2005, without type 2 diabetes.Results: Incident dysglycemia developed in 26 participants during the 5-year period. Higher daily steps in 2000 were independently associated with a lower 5-year risk of incident dysglycemia (adjusted odds ratio [AOR] 0.87 [95% CI 0.77-0.97] per 1,000-step increment). Higher daily steps in 2005, after controlling for baseline steps in 2000 (thus reflecting change in steps over 5 years), were not associated with incident dysglycemia (AOR 1.02 [0.92-1.14]). Higher daily steps in 2000 were also associated with lower fasting blood glucose, but not 2-h plasma glucose by 2005. Further adjustment for BMI or waist circumference did not remove these associations.Conclusions: Among community-dwelling adults, a higher rate of daily steps is associated with a reduced risk of incident dysglycemia. This effect appears to be not fully mediated through reduced adiposity. [ABSTRACT FROM AUTHOR]

Objective: To examine whether serum 25-hydroxyvitamin D (25OHD) and dietary calcium predict incident type 2 diabetes and insulin sensitivity.Research Design and Methods: A total of 6,537 of the 11,247 adults evaluated in 1999-2000 in the Australian Diabetes, Obesity and Lifestyle (AusDiab) study, returned for oral glucose tolerance test (OGTT) in 2004-2005. We studied those without diabetes who had complete data at baseline (n = 5,200; mean age 51 years; 55% were women; 92% were Europids). Serum 25OHD and energy-adjusted calcium intake (food frequency questionnaire) were assessed at baseline. Logistic regression was used to evaluate associations between serum 25OHD and dietary calcium on 5-year incidence of diabetes (diagnosed by OGTT) and insulin sensitivity (homeostasis model assessment of insulin sensitivity [HOMA-S]), adjusted for multiple potential confounders, including fasting plasma glucose (FPG).Results: During the 5-year follow-up, 199 incident cases of diabetes were diagnosed. Those who developed diabetes had lower serum 25OHD (mean 58 vs. 65 nmol/L; P < 0.001) and calcium intake (mean 881 vs. 923 mg/day; P = 0.03) compared with those who remained free of diabetes. Each 25 nmol/L increment in serum 25OHD was associated with a 24% reduced risk of diabetes (odds ratio 0.76 [95% CI 0.63-0.92]) after adjusting for age, waist circumference, ethnicity, season, latitude, smoking, physical activity, family history of diabetes, dietary magnesium, hypertension, serum triglycerides, and FPG. Dietary calcium intake was not associated with reduced diabetes risk. Only serum 25OHD was positively and independently associated with HOMA-S at 5 years.Conclusions: Higher serum 25OHD levels, but not higher dietary calcium, were associated with a significantly reduced risk of diabetes in Australian adult men and women. [ABSTRACT FROM AUTHOR]

Objective: To determine the longitudinal association of components of health-related functioning (HRF) with incident impaired glucose metabolism and type 2 diabetes.Research Design and Methods: The Australian Diabetes Obesity and Lifestyle (AusDiab) study is a national, longitudinal study of adults aged > or =25 years from 42 randomly selected areas of Australia. Diabetes status was defined using the World Health Organization criteria, and HRF was assessed using the SF-36 questionnaire in 1999-2000 and 2004-2005.Results: Incident impaired fasting glucose (IFG), impaired glucose tolerance (IGT), and newly diagnosed type 2 diabetes were associated with increased bodily pain at baseline compared with those with normal glucose tolerance (NGT) (IFG P = 0.005, IGT P < 0.004, and newly diagnosed type 2 diabetes P = 0.005), after adjustment. In addition, those with incident IGT and newly diagnosed type 2 diabetes had significantly reduced physical functioning, general health, mental health, and vitality at baseline compared with those with NGT. After we controlled for factors associated with incident diabetes, those in the lowest quartile of the physical component summary scale at baseline had at least a 50% higher risk of progression to impaired glucose metabolism and diabetes 5 years later.Conclusions: These findings show that incident IFG, IGT, and newly diagnosed type 2 diabetes are associated with reduced HRF independent of cardiovascular disease and that this is evident before the onset of these conditions. If future health promotion campaigns are to effectively target those at high risk of developing diabetes, an understanding of the process of declining health before onset of the disease is essential. [ABSTRACT FROM AUTHOR]

Objective: We examined the associations of sitting time and television (TV) viewing time with continuously measured biomarkers of cardio-metabolic risk in Australian adults.Research Design and Methods: Waist circumference, BMI, resting blood pressure, triglycerides, HDL cholesterol, fasting and 2-h postload plasma glucose, and fasting insulin were measured in 2,761 women and 2,103 men aged > or =30 years (mean age 54 years) without clinically diagnosed diabetes from the 2004-2005 Australian Diabetes, Obesity and Lifestyle (AusDiab) study. Multivariate linear regression analyses examined associations of self-reported sitting time and TV viewing time (hours per day) with these biomarkers, adjusting for potential confounding variables.Results: For both women and men, sitting time was detrimentally associated with waist circumference, BMI, systolic blood pressure, fasting triglycerides, HDL cholesterol, 2-h postload plasma glucose, and fasting insulin (all P < 0.05), but not with fasting plasma glucose and diastolic blood pressure (men only). With the exception of HDL cholesterol and systolic blood pressure in women, the associations remained significant after further adjustment for waist circumference. TV viewing time was detrimentally associated with all metabolic measures in women and all except HDL cholesterol and blood pressure in men. Only fasting insulin and glucose (men only) remained deleteriously associated with TV viewing time after adjustment for waist circumference.Conclusions: In women and men, sitting time and TV viewing time were deleteriously associated with cardio-metabolic risk biomarkers, with sitting time having more consistent associations in both sexes and being independent of central adiposity. Preventive initiatives aimed at reducing sitting time should focus on both nonleisure and leisure-time domains. [ABSTRACT FROM AUTHOR]

Objective: We determined the longitudinal association of glucose metabolism with retinopathy in a sample of the Australian population.Research Design and Methods: The Australian Diabetes Obesity and Lifestyle (AusDiab) study is a national, longitudinal study of adults aged > or =25 years from 42 randomly selected areas of Australia. Retinopathy was assessed at baseline in 1999-2000 and 5 years later in 2004-2005 in participants identified as having diabetes (based on self-report and oral glucose tolerance test) and impaired glucose metabolism and in a random sample with normal glucose tolerance. Complete retinal data were available for 1,192 participants. Photographs were graded at two time points according to a simplified version of the Wisconsin grading system.Results: The 5-year incidences of retinopathy were 13.9 and 3.0% among those with known and newly diagnosed diabetes at baseline, respectively. Of those who developed incident newly diagnosed diabetes at follow-up, 11.9% had retinopathy at baseline compared with 5.6% of those who did not progress to incident newly diagnosed diabetes (P = 0.037). After adjustment for factors identified as risk factors for diabetes, individuals with retinopathy signs at baseline were twice as likely to develop incident newly diagnosed diabetes compared with those who did not have retinopathy signs at baseline.Conclusions: The 5-year incidence of retinopathy was 13.9% among individuals with known diabetes. Nondiabetic individuals with retinopathy signs at baseline had a twofold higher risk of developing incident newly diagnosed diabetes 5 years later. This result provides further evidence that mild retinopathy signs may be a preclinical marker of underlying microvascular disease and future diabetes risk. [ABSTRACT FROM AUTHOR]

PURPOSE: Among Australian adults who met the public health guideline for the minimum health-enhancing levels of physical activity, we examined the dose-response associations of television-viewing time with continuous metabolic risk variables. METHODS: Data were analyzed on 2031 men and 2033 women aged >/= 25 yr from the 1999-2000 Australian Diabetes, Obesity and Lifestyle study without clinically diagnosed diabetes or heart disease, who reported at least 2.5 h.wk of moderate- to vigorous-intensity physical activity. Waist circumference, resting blood pressure, and fasting and 2-h plasma glucose, triglycerides, and high-density-lipoprotein cholesterol (HDL-C) were measured. The cross-sectional associations of these metabolic variables with quartiles and hours per day of self-reported television-viewing time were examined separately for men and for women. Analyses were adjusted for age, education, income, smoking, diet quality, alcohol intake, parental history of diabetes, and total physical activity time, as well as menopausal status and current use of postmenopausal hormones for women. RESULTS: Significant, detrimental dose-response associations of television-viewing time were observed with waist circumference, systolic blood pressure, and 2-h plasma glucose in men and women, and with fasting plasma glucose, triglycerides, and HDL-C in women. The associations were stronger in women than in men, with significant gender interactions observed for triglycerides and HDL-C. Though waist circumference attenuated the associations, they remained statistically significant for 2-h plasma glucose in men and women, and for triglycerides and HDL-C in women. CONCLUSIONS: In a population of healthy Australian adults who met the public health guideline for physical activity, television-viewing time was positively associated with a number of metabolic risk variables. These findings support the case for a concurrent sedentary behavior and health guideline for adults, which is in addition to the public health guideline on physical activity. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Total sedentary (absence of whole-body movement) time is associated with obesity, abnormal glucose metabolism, and the metabolic syndrome. In addition to the effects of total sedentary time, the manner in which it is accumulated may also be important. We examined the association of breaks in objectively measured sedentary time with biological markers of metabolic risk. RESEARCH DESIGN AND METHODS: Participants (n = 168, mean age 53.4 years) for this cross-sectional study were recruited from the 2004-2005 Australian Diabetes, Obesity and Lifestyle study. Sedentary time was measured by an accelerometer (counts/minute(-1) < 100) worn during waking hours for seven consecutive days. Each interruption in sedentary time (counts/min > or = 100) was considered a break. Fasting plasma glucose, 2-h plasma glucose, serum triglycerides, HDL cholesterol, weight, height, waist circumference, and resting blood pressure were measured. MatLab was used to derive the breaks variable; SPSS was used for the statistical analysis. RESULTS: Independent of total sedentary time and moderate-to-vigorous intensity activity time, increased breaks in sedentary time were beneficially associated with waist circumference (standardized beta = -0.16, 95% CI -0.31 to -0.02, P = 0.026), BMI (beta = -0.19, -0.35 to -0.02, P = 0.026), triglycerides (beta = -0.18, -0.34 to -0.02, P = 0.029), and 2-h plasma glucose (beta = -0.18, -0.34 to -0.02, P = 0.025). CONCLUSIONS: This study provides evidence of the importance of avoiding prolonged uninterrupted periods of sedentary (primarily sitting) time. These findings suggest new public health recommendations regarding breaking up sedentary time that are complementary to those for physical activity. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To examine the relationship of retinal vascular caliber to incident diabetes in a population-based cohort. RESEARCH DESIGN AND METHODS: The Australian Diabetes, Obesity and Lifestyle (AusDiab) Study recruited adults aged 25+ years across Australia in 1999-2000, with a follow-up 5 years later in 2004-2005. Participants' glycemic status was classified using fasting plasma glucose (FPG) and 2-h oral glucose tolerance (2-h plasma glucose [2hPG]) tests. Diabetes was diagnosed if FPG was >or=7.0 mmol/l or 2hPG was >or=11.1 mmol/l. Retinal vascular caliber was measured from baseline retinal photographs using a computer-assisted program. RESULTS: Of the 803 participants without diabetes at baseline, 108 (13.4%) developed diabetes at follow-up: 7 (2.8%) of 246 participants with normal glucose tolerance, 9 (13.6%) of 66 participants with impaired fasting glucose, and 92 (18.7%) of 491 participants with impaired glucose tolerance. After multivariate analysis, participants with narrower retinal arteriolar caliber had a higher risk of diabetes (odds ratio 2.21 [95% CI 1.02-4.80], comparing smallest versus highest arteriolar caliber tertiles, P = 0.04 for trend). There was no association between retinal venular caliber and incident diabetes. CONCLUSIONS: Narrower retinal arteriolar caliber predicted risk of diabetes. These data provide further evidence that microvascular changes may contribute to the pathogenesis of diabetes. [ABSTRACT FROM AUTHOR]

OBJECTIVE: We examined the associations of physical activity with fasting plasma glucose (FPG) and with 2-h postload plasma glucose (2-h PG) in men and women with low, moderate, and high waist circumference. RESEARCH DESIGN AND METHODS: The Australian Diabetes, Obesity and Lifestyle (AusDiab) study provided data on a population-based cross-sectional sample of 4,108 men and 5,106 women aged >/=25 years without known diabetes or health conditions that could affect physical activity. FPG and 2-h PG were obtained from an oral glucose tolerance test. Self-reported physical activity level was defined according to the current public health guidelines as active (>/=150 min/week across five or more sessions) or inactive (<150 min/week and/or less than five sessions). Sex-specific quintiles of physical activity time were used to ascertain dose response. RESULTS: Being physically active and total physical activity time were independently and negatively associated with 2-h PG. When physical activity level was considered within each waist circumference category, 2-h PG was significantly lower in active high-waist circumference women (beta -0.30 [95% CI -0.59 to -0.01], P = 0.044) and active low-waist circumference men (beta -0.25 [-0.49 to -0.02], P = 0.036) compared with their inactive counterparts. Considered across physical activity and waist circumference categories, 2-h PG levels were not significantly different between active moderate-waist circumference participants and active low-waist circumference participants. Associations between physical activity and FPG were nonsignificant. CONCLUSIONS: There are important differences between 2-h PG and FPG related to physical activity. It appears that 2-h PG is more sensitive to the beneficial effects of physical activity, and these benefits occur across the waist circumference spectrum. [ABSTRACT FROM AUTHOR]

Objective: Confirmatory factor analysis (CFA) was used to test the hypothesis that the components of the metabolic syndrome are manifestations of a single common factor.Research Design and Methods: Three different datasets were used to test and validate the model. The Spanish and Mauritian studies included 207 men and 203 women and 1,411 men and 1,650 women, respectively. A third analytical dataset including 847 men was obtained from a previously published CFA of a U.S. population. The one-factor model included the metabolic syndrome core components (central obesity, insulin resistance, blood pressure, and lipid measurements). We also tested an expanded one-factor model that included uric acid and leptin levels. Finally, we used CFA to compare the goodness of fit of one-factor models with the fit of two previously published four-factor models.Results: The simplest one-factor model showed the best goodness-of-fit indexes (comparative fit index 1, root mean-square error of approximation 0.00). Comparisons of one-factor with four-factor models in the three datasets favored the one-factor model structure. The selection of variables to represent the different metabolic syndrome components and model specification explained why previous exploratory and confirmatory factor analysis, respectively, failed to identify a single factor for the metabolic syndrome.Conclusions: These analyses support the current clinical definition of the metabolic syndrome, as well as the existence of a single factor that links all of the core components. [ABSTRACT FROM AUTHOR]

Objective: The goal of this study was to assess the associations of physical activity time and television (TV) time with risk of "undiagnosed" abnormal glucose metabolism in Australian adults.Research Design and Methods: This population-based cross-sectional study using a stratified cluster design involving 42 randomly selected Census Collector Districts across Australia included 8,299 adults aged 25 years or older who were free from new type 2 diabetes and self-reported ischemic disease and did not take lipid-lowering or antihypertensive drugs. Abnormal glucose metabolism (impaired fasting glycemia [IFG], impaired glucose tolerance [IGT], or new type 2 diabetes) was based on an oral glucose tolerance test. Self-reported physical activity time and TV time (previous week) were assessed using interviewer-administered questionnaires.Results: After adjustment for known confounders and TV time, the odds ratio (OR) of having abnormal glucose metabolism was 0.62 (95% CI 0.41-0.96) in men and 0.71 (0.50-1.00) in women for those engaged in physical activity >or=2.5 h/week compared with those who were sedentary (0 h/week). The ORs of having abnormal glucose metabolism were 1.16 (0.79-1.70) in men and 1.49 (1.12-1.99) in women who watched TV >14 h/week compared with those who watched 14 h/week) was also associated with an increased risk of new type 2 diabetes in men and women and IGT in women compared with those watching <14 h/week. Total physical activity of >or=2.5 h/week was associated with a reduced risk of IFG, IGT, and new type 2 diabetes in both sexes; however, only the association with IGT in women was statistically significant.Conclusions: These findings suggest a protective effect of physical activity and a deleterious effect of TV time on the risk of abnormal glucose metabolism in adults. Population strategies to reduce risk of abnormal glucose metabolism should focus on reducing sedentary behaviors such as TV time, as well as increasing physical activity. [ABSTRACT FROM AUTHOR]

BACKGROUND: In the Diabetes Prevention Program (DPP), interventions with metformin (plus standard lifestyle advice) or intensive lifestyle changes (ILC) reduced the risk of developing type 2 diabetes mellitus (DM) by 31% and 58%, respectively, versus control (standard lifestyle advice only) in patients with impaired glucose tolerance (IGT). OBJECTIVE: The goal of this study was to establish whether implementing the active treatments used in the DPP would be cost-effective in Australia, France, Germany, Switzerland, and the United Kingdom. METHODS: A Markov model simulated 3 states-IGT, type 2 DM, and deceased-using probabilities from the DPP and published data. Country-specific direct costs were used throughout. RESULTS: Assuming only within-trial effects and costs of interventions, both metformin and ILC improved life expectancy versus control. Mean improvements in nondiscounted life expectancy were 0.11 and 0.22 years for metformin and ILC, respectively. Both interventions were associated with cost savings versus control in all countries except the United Kingdom, where a small increase in costs was observed in both intervention arms. When a lifetime effect of interventions was assumed, incremental improvements in life expectancy were 0.35 and 0.90 years for metformin and ILC, respectively. Results were sensitive to probabilities of developing type 2 DM, the projected long-term duration of effect of interventions after the 3-year trial period, the relative risk of mortality for type 2 DM compared with IGT, and the costs of implementing the interventions. CONCLUSIONS: Based on probabilities from the DPP and published data, in this model analysis, incorporation of the DPP interventions into clinical practice in 5 developed countries was projected to lead to an increase in DM-free years of life, improvements in life expectancy, and either cost savings or minor increases in costs compared with standard lifestyle advice in a population with IGT. Thus, financial constraints should not prevent the implementation of DM prevention programs. [ABSTRACT FROM AUTHOR]

Changes in retinal vascular caliber may reflect subclinical microvascular disease and provide prognostic information regarding risk of retinopathy. In this study, we examined the prospective association of retinal vascular caliber with retinopathy risk in an Australian population-based cohort. A total of 906 participants without retinopathy at baseline had retinal vascular caliber measured from photographs and were followed-up for 5 years for incident retinopathy. After adjusting for age, sex, systolic blood pressure, A1C, and other risk factors, individuals with wider retinal arteriolar caliber (widest 25% vs. the remaining three-quarters of the population) were more likely to develop incident retinopathy (odds ratio 4.79 [95% CI 1.57-14.58]). This association was not significant in individuals without diabetes. Venular caliber did not predict incident retinopathy. Our findings suggest that retinal arteriolar dilatation is a specific sign of diabetic microvascular dysfunction and may be a preclinical marker of diabetic retinopathy. [ABSTRACT FROM AUTHOR]

OBJECTIVE: We examined the associations of objectively measured sedentary time and physical activity with continuous indexes of metabolic risk in Australian adults without known diabetes. RESEARCH DESIGN AND METHODS: An accelerometer was used to derive the percentage of monitoring time spent sedentary and in light-intensity and moderate-to-vigorous-intensity activity, as well as mean activity intensity, in 169 Australian Diabetes, Obesity and Lifestyle Study (AusDiab) participants (mean age 53.4 years). Associations with waist circumference, triglycerides, HDL cholesterol, resting blood pressure, fasting plasma glucose, and a clustered metabolic risk score were examined. RESULTS: Independent of time spent in moderate-to-vigorous-intensity activity, there were significant associations of sedentary time, light-intensity time, and mean activity intensity with waist circumference and clustered metabolic risk. Independent of waist circumference, moderate-to-vigorous-intensity activity time was significantly beneficially associated with triglycerides. CONCLUSIONS: These findings highlight the importance of decreasing sedentary time, as well as increasing time spent in physical activity, for metabolic health. [ABSTRACT FROM AUTHOR]