Search

Low dose persistent organic pollutants (POPs) have emerged as a new risk for type 2 diabetes (T2D). Despite substantial evidence from human and experimental studies, there are several critical issues which have not been properly addressed by POPs researchers. First, as POPs exist as mixtures, findings about POPs from human studies should be interpreted from the viewpoint of lipophilic chemical mixtures which include both measured and unmeasured POPs. Second, as POPs can directly reduce insulin secretion of beta cells, the role of POPs may be more prominent in the development of beta-cell dysfunction-dominant T2D rather than insulin resistance-dominant T2D. Third, there are multidimensional interrelationships between POPs and adipose tissue. Even though POPs are now considered as a new risk factor for T2D, independent of obesity, POPs and obesity are mechanistically linked to each other. POPs are involved in key mechanisms linking obesity and T2D, such as chronic inflammation of adipose tissue and lipotoxicity with ectopic fat accumulation. Also, POPs can explain puzzling human findings which suggest benefits of obesity because healthy adipose tissue can be protective by reducing the amount of POPs reaching other organs. Fourth, non-linear dose-response relationships between POPs and T2D are biologically possible. Although POPs are well-known endocrine disrupting chemicals (EDCs), mitochondrial dysfunction may be a more plausible mechanism due to unpredictability of EDC mixtures. As adipose tissue plays a role as an internal exposure source of POPs, how to manage POPs inside us may be essential to protect against harms of POPs. [ABSTRACT FROM AUTHOR]

Importance: Hemoglobin A1c (HbA1c) reflects past glucose concentrations, but this relationship may differ between those with sickle cell trait (SCT) and those without it.Objective: To evaluate the association between SCT and HbA1c for given levels of fasting or 2-hour glucose levels among African Americans.Design, Setting, and Participants: Retrospective cohort study using data collected from 7938 participants in 2 community-based cohorts, the Coronary Artery Risk Development in Young Adults (CARDIA) study and the Jackson Heart Study (JHS). From the CARDIA study, 2637 patients contributed a maximum of 2 visits (2005-2011); from the JHS, 5301 participants contributed a maximum of 3 visits (2000-2013). All visits were scheduled at approximately 5-year intervals. Participants without SCT data, those without any concurrent HbA1c and glucose measurements, and those with hemoglobin variants HbSS, HbCC, or HbAC were excluded. Analysis of the primary outcome was conducted using generalized estimating equations (GEE) to examine the association of SCT with HbA1c levels, controlling for fasting or 2-hour glucose measures.Exposures: Presence of SCT.Main Outcomes and Measures: Hemoglobin A1c stratified by the presence or absence of SCT was the primary outcome measure.Results: The analytic sample included 4620 participants (mean age, 52.3 [SD, 11.8] years; 2835 women [61.3%]; 367 [7.9%] with SCT) with 9062 concurrent measures of fasting glucose and HbA1c levels. In unadjusted GEE analyses, for a given fasting glucose, HbA1c values were statistically significantly lower in those with (5.72%) vs those without (6.01%) SCT (mean HbA1c difference, -0.29%; 95% CI, -0.35% to -0.23%). Findings were similar in models adjusted for key risk factors and in analyses using 2001 concurrent measures of 2-hour glucose and HbA1c concentration for those with SCT (mean, 5.35%) vs those without SCT (mean, 5.65%) for a mean HbA1c difference of -0.30% (95% CI, -0.39% to -0.21%). The HbA1c difference by SCT was greater at higher fasting (P = .02 for interaction) and 2-hour (P = .03) glucose concentrations. The prevalence of prediabetes and diabetes was statistically significantly lower among participants with SCT when defined using HbA1c values (29.2% vs 48.6% for prediabetes and 3.8% vs 7.3% for diabetes in 572 observations from participants with SCT and 6877 observations from participants without SCT; P<.001 for both comparisons).Conclusions and Relevance: Among African Americans from 2 large, well-established cohorts, participants with SCT had lower levels of HbA1c at any given concentration of fasting or 2-hour glucose compared with participants without SCT. These findings suggest that HbA1c may systematically underestimate past glycemia in black patients with SCT and may require further evaluation. [ABSTRACT FROM AUTHOR]

OBJECTIVE--Adverse microbial exposures might contribute to diabetogenesis. We hypothesized that clinical periodontal disease (a manifestation of microbial exposures in dysbiotic biofilms) would be related to insulin resistance among diabetes-free participants. The roles of inflammatory mediation and effect modification were also studied. RESEARCH DESIGN AND METHODS--The continuous National Health and Nutrition Examination Survey 1999-2004 enrolled 3,616 participants (51% women) who received a periodontal examination and fasting blood draw. Participants were mean age (±SD) 43±17 years and 28% Hispanic, 52% Caucasian, 17% African American, and 3% other. Log-transformed values of the homeostasis model assessment of insulin resistance (HOMA-IR) or HOMA-IR ≥ 3.30 (75th percentile) were regressed across full-mouth periodontal probing depth (PD) levels using linear and logistic models. White blood cell (WBC) count and C-reactive protein (CRP) were considered as either mediators or effect modifiers in separate analyses. Risk ratios (RRs) stem from marginal predictions derived from the logistic model. Results were adjusted for multiple periodontal disease and insulin resistance risk factors. RESULTS--In linear regression, geometric mean HOMA-IR levels increased by 1.04 for every 1-mm PD increase (P = 0.007). WBC mediated 6% of the association (P < 0.05). Among participants with WBC ≤6.4 x 109, PD was unrelated to HOMA-IR ≥3.30. Fourth-quartile PD was associated with HOMA-IR ≥3.30 among participants with WBC >7.9 x 109; RR 2.60 (1.36-4.97) (P for interaction = 0.05). Findings were similar among participants with CRP >3.0 mg/L (P for interaction = 0.04). CONCLUSIONS--Periodontal infection was associated with insulin resistance in a nationally representative U.S. sample of diabetes-free adults. These data support the role of inflammation as both mediator and effect modifier of the association. [ABSTRACT FROM AUTHOR]

Metabolic syndrome (MetS), Type 2 diabetes (T2D), and cardiovascular disease (CVDI share an inflammatory etiology and are known to be influenced by diet. We investigated associations of hypothesized prooxidative (Fe) and antioxidative (Zn, Mg, β-carotene, vitamin C, vitamin E) micronutrients with incident MetS, T2D, and CVD in the Multi-Ethnic Study of Atherosclerosis. Participants, 45-84 y at baseline (2000-2002), were followed through 2010. Diet was assessed by FFQ. After adjusting for demographics and behavioral confounders, including BMI, dietary vitamin E intake was inversely associated with incident MetS and CVD [HR for extreme quintiles: MetS = 0.78 195% Cl = 0.62, 0.97), P-trend = 0.01; CVD: HR = 0.69 (95% Cl = 0.46, 1.031, P-trend = 0.04]. Intakes of heme iron and Zn from red meat, but not from other sources, were positively associated with risk of MetS theme iron from red meat: HR = 1.25 (95% Cl = 0.99,1.56), P-trend = 0.03; Zn from red meat: HR = 1.29 (95% Cl = 1.03,1.61), P-trend = 0.04] and CVD ]heme iron from red meat: HR = 1.65 (95% Cl = 1.10,2.47), P-trend = 0.01; Zn from red meat: HR = 1.51(95% Cl = 1.02, 2.24), P-trend = 0.01]. Dietary intakes of nonheme iron, Mg, vitamin C, and β-carotene were not associated with risk of MetS, T2D, or CVD. Data provided little support for the associations between specific micronutrients and MetS, T2D, or CVD. However, nutrients consumed in red meat, or red meat as a whole, may increase risk of MetS and CVD. [ABSTRACT FROM AUTHOR]

OBJECTIVE--Persistent organic pollutants (POPs), lipophilic chemicals that accumulate mainly in adipose tissue, have recently been linked to type 2 diabetes. However, evidence from prospective studies is sparse. This study was performed to evaluate prospective associations of type 2 diabetes with selected POPs among the elderly. RESEARCH DESIGN AND METHODS--Nineteen POPs (14 polychlorinated biphenyl [PCB] congeners, 3 organochlorine pesticides, 1 brominated diphenyl ether, and 1 dioxin) were measured in plasma collected at baseline in 725 participants, aged 70 years, of the Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS). RESULTS--After adjusting for known type 2 diabetes risk factors, including obesity, odds ratios (ORs) (95% CIs) for type 2 diabetes at age 75 years (n = 36) according to the quintiles of a summary measure of concentrations of PCBs (vs. the lowest quintile) were 4.5, 5.1, 8.8 (1.8- 42.7), and 7.5 (1.4-38.8) (Ptrend <0.01). Among organochlorine pesticides, adjusted ORs across concentrations of trans-nonachlor showed that Ptrend = 0.03. Adjusted ORs (95% CIs) across quintiles of the sum of three organochlorine pesticides were 1.1, 1.6, 1.5, and 3.4 (1.0-11.7) (Ptrend = 0.03). Neither brominated diphenyl ether 47 nor dioxin was significantly associated with incident diabetes. The sum of PCBs improved reclassification significantly when added to traditional risk factors for diabetes. CONCLUSIONS--Despite the small number of incident cases, this study found that environmental exposure to some POPs substantially increased risk of future type 2 diabetes in an elderly population. [ABSTRACT FROM AUTHOR]

Background: There is emerging evidence that background exposure to persistent organic pollutants (POPs) are important in the development of conditions predisposing to diabetes as well as of type 2 diabetes itself. We recently reported that low dose POPs predicted incident type 2 diabetes in a nested case-control study. The current study examined if low dose POPs predicted future adiposity, dyslipidemia, and insulin resistance among controls without diabetes in that study. Methodology/Principal Findings: The 90 controls were diabetes-free during 20 years follow-up. They were a stratified random sample, enriched with overweight and obese persons. POPs measured in 1987-88 (year 2) sera included 8 organochlorine (OC) pesticides, 22 polychlorinated biphenyls (PCBs), and 1 polybrominated biphenyl (PBB). Body mass index (BMI), triglycerides, HDL-cholesterol, LDL-cholesterol, and homeostasis model assessment value for insulin resistance (HOMA-IR) were study outcomes at 2005-06 (year 20). The evolution of study outcomes during 18 years by categories of serum concentrations of POPs at year 2 was evaluated by adjusting for the baseline values of outcomes plus potential confounders. Parallel to prediction of type 2 diabetes, many statistically significant associations of POPs with dysmetabolic conditions appeared at low dose, forming inverted U-shaped dose-response relations. Among OC pesticides, p,p'-DDE most consistently predicted higher BMI, triglycerides, and HOMA-IR and lower HDL-cholesterol at year 20 after adjusting for baseline values. Oxychlordane, trans-nonachlor, and hexachlorobenzene also significantly predicted higher triglycerides. Persistent PCBs with ≥7 chlorides predicted higher BMI, triglycerides, and HOMA-IR and lower HDL-cholesterol at year 20 with similar dose-response curves. Conclusions/Significance: Simultaneous exposure to various POPs in the general population may contribute to development of obesity, dyslipidemia, and insulin resistance, common precursors of type 2 diabetes and cardiovascular diseases. Although obesity is a primary cause of these metabolic abnormalities, POPs exposure may contribute to excess adiposity and other features of dysmetabolism. [ABSTRACT FROM AUTHOR]

OBJECTIVE-- To investigate the long-term associations of magnesium intake with incidence of diabetes, systemic inflammation, and insulin resistance among young American adults. RESEARCH DESIGN AND METHODS-- A total of 4,497 Americans, aged 18-30 years, who had no diabetes at baseline, were prospectively examined for incident diabetes based on quintiles of magnesium intake. We also investigated the associations between magnesium intake and inflammatory markers, i.e., high-sensitivity C-reactive protein (hs-CRP), interleukin6 (IL-6), and fibrinogen, and the homeostasis model assessment of insulin resistance (HOMA-IR). RESULTS-- During the 20-year follow-up, 330 incident cases of diabetes were identified. Magnesium intake was inversely associated with incidence of diabetes after adjustment for potential confounders. The multivariable-adjusted hazard ratio of diabetes for participants in the highest quintile of magnesium intake was 0.53 (95% CI, 0.32- 0.86; P[sub trend] < 0.01) compared with those in the lowest quintile. Consistently, magnesium intake was significantly inversely associated with hs-CRP, IL-6, fibrinogen, and HOMA-IR, and serum magnesium levels were inversely correlated with hs-CRP and HOMA-IR. CONCLUSIONS-- Magnesium intake was inversely longitudinally associated with incidence of diabetes in young American adults. This inverse association may be explained, at least in part, by the inverse correlations of magnesium intake with systemic inflammation and insulin resistance. [ABSTRACT FROM AUTHOR]

This study examined prepregnancy cardiometabolic risk factors and gestational diabetes mellitus (GDM) in subsequent pregnancies. The authors selected 1,164 women without diabetes before pregnancy who delivered 1,809 livebirths between 5 consecutive examinations from 1985 to 2006 in the Coronary Artery Risk Development in Young Adults (CARDIA) Study. The authors measured prepregnancy cardiometabolic risk factors and performed multivariate repeated-measures logistic regression to compute the odds of GDM adjusted for race, age, parity, birth order, and other covariates. Impaired fasting glucose (100–125 vs. <90 mg/dL), elevated fasting insulin (>15–20 and >20 vs. <10 μU/mL), and low levels of high-density lipoprotein cholesterol (<40 vs. >50 mg/dL) before pregnancy were directly associated with GDM: The odds ratios = 4.74 (95% confidence interval (CI): 2.14, 10.51) for fasting glucose, 2.19 (95% CI: 1.15, 4.17) for middle insulin levels and 2.36 (95% CI: 1.20, 4.63) for highest insulin levels, and 3.07 (95% CI: 1.62, 5.84) for low levels of high-density lipoprotein cholesterol among women with a negative family history of diabetes; all P < 0.01. Among overweight women, 26.7% with 1 or more cardiometabolic risk factors developed GDM versus 7.4% with none. Metabolic impairment exists before GDM pregnancy in nondiabetic women. Interconceptual metabolic screening could be included in routine health assessments to identify high-risk women for GDM in a subsequent pregnancy and to potentially minimize fetal exposure to metabolic abnormalities that program future disease. [ABSTRACT FROM PUBLISHER]

BACKGROUND: Low doses of some persistent organic pollutants (POPs) associate cross-sectionally with type 2 diabetes, whereas associations with high POP exposures are inconsistent. OBJECTIVES: We investigated whether several POPs prospectively predict type 2 diabetes within the Coronary Artery Risk Development in Young Adults (CARDIA) cohort. METHODS: Participants in this nested case--control study were diabetes free in 1987-1988. By 2005-2006, the 90 controls remained free of diabetes, whereas the 90 cases developed diabetes. Using serum collected in 1987-1988, we measured 8 organochlorine pesticides, 22 polychlorinated biphenyl congeners (PCBs), and 1 polybrominated biphenyl (PBB). We compared POP concentrations from CARDIA and the National Health and Nutrition Examination Survey (NHANES) in 2003-2004. We computed odds ratios (ORs) for incident diabetes using logistic regression analysis. RESULTS: Chlorinated POPs in CARDIA in 1987-1988 were much higher than corresponding NHANES 2003-2004 concentrations. POPs showed nonlinear associations with diabetes risk. The highest risk was observed in the second quartiles of trans-nonachlor, oxychlordane, mirex, highly chlorinated PCBs, and PBB153--a finding that suggests low-dose effects. We concentrated risk by summing these POPs and isolated very low concentrations of multiple POPs in the lowest sextile of the sum. The adjusted OR in the second sextile vs. the lowest sextile was 5.3 overall and 20.1 for body mass index ≤ 30 kg/m2. CONCLUSIONS: Several POPs at low doses similar to current exposure levels may increase diabetes risk, possibly through endocrine disruption. Certain POPs may a play a role in the current epidemic of diabetes, which has been attributed to obesity. [ABSTRACT FROM AUTHOR]

This study examined how adiposity influences racial/ethnic differences in diabetes incidence by exploring whether relations between anthropometric measures and incident diabetes vary by race/ethnicity. Data from the Multi-Ethnic Study of Atherosclerosis initiated in 2000 (n = 5,446 US men and women aged 45–84 years) were analyzed by using proportional hazards and Poisson regression. The diabetes incidence rate was 2/100 person-years (n = 479 cases). Interactions were present between race and anthropometry (P-interaction(race × body mass index) = 0.002). The slope of incident diabetes per anthropometric unit was greatest for Chinese, less for whites and Hispanics, and still less for blacks. For small waist, risk of incident diabetes was <1/100 person-years for all racial/ethnic groups. At intermediate waist levels, Chinese had the highest and whites the lowest rates of incident diabetes. At the respective 95th percentiles of waist circumference, risk of incident diabetes per 100 person-years was 3.9 for Chinese (104 cm), 3.5 for whites (121 cm), 5.0 for blacks (125 cm), and 5.3 for Hispanics (121 cm). Adiposity influenced relative diabetes occurrence across racial/ethnic groups, in that Chinese had a steeper diabetes risk per unit of adiposity. However, the generally low level of adiposity in Chinese led to a relatively low diabetes occurrence. [ABSTRACT FROM PUBLISHER]

OBJECTIVE -- To test the hypothesis that A1C is associated with subclinical cardiovascular disease (CVD) in a population without evident diabetes, after adjusting for traditional CVD risk factors and BMI. RESEARCH DESIGN AND METHODS -- This was a cross-sectional study of 5,121 participants without clinically evident CVD or diabetes (fasting glucose ≥7.0 mmol/l or use of diabetes medication), aged 47-86 years, enrolled in the Multi-Ethnic Study of Atherosclerosis (MESA). Measurements included carotid intimal-medial wall thickness (CIMT) and coronary artery calcification (CAC). Results were adjusted for age, sex, ethnicity, smoking, systolic blood pressure, LDL cholesterol, HDL cholesterol, antihypertensive medication use, lipid-lowering medication use, and BMI. RESULTS -- Compared with those in the lowest quartile for A1C ([mean ± SD] 5.0 ± 0.2%), participants in the highest quartile (6.0 ± 0.3%) had higher adjusted mean values for common CIMT (0.85 vs. 0.87 mm, P = 0.003) and internal CIMT (1.01 vs. 1.08 mm, P = 0.003). A1C quartile was not associated with prevalence of CAC in the entire cohort (P = 0.27); however, the association was statistically significant in women (adjusted prevalence of CAC in lowest and highest A1C quartiles 37.5 vs. 43.0%, P = 0.01). Among those with some CAC, higher A1C quartile tended to be associated with higher CAC score, but the results were not statistically significant (adjusted P = 0.11). CONCLUSIONS -- In this multiethnic cohort, there were small, positive associations between A1C, common CIMT, and internal CIMT in the absence of clinically evident diabetes. An association between higher A1C and CAC prevalence was evident only in women. [ABSTRACT FROM AUTHOR]

OBJECTIVE -- Chlorinated persistent organic pollutants (POPs), endocrine disruptors accumulated in adipose tissue, were associated with diabetes and metabolic syndrome. Brominated flame retardants (BFRs), such as polybrominated diphenyl ethers (PBDEs) or polybrominated biphenyls (PBBs), are another class of POPs for which body burden is increasing. Cross-sectional associations of serum concentrations of BFRs with diabetes and metabolic syndrome were studied. RESEARCH DESIGN AND METHODS -- In the National Health and Nutrition Examination Survey 2003-2004, 1,367 adults were examined with respect to diabetes status. Five PBDEs and one PBB were selected, detectable in ≥60% of participants. For the outcome metabolic syndrome, we restricted the analysis to 637 participants with a morning fasting sample. RESULTS -- Compared with subjects with serum concentrations below the limit of detection, prevalent diabetes had differing dose-response associations with serum concentrations of PBB-153 and PBDE-153. Adjusted odds ratios across quartiles of serum concentrations for PBB-153 or PBDE-153 were 1.0, 0.7, 1.4, 1.6, and 1.9 (P for trend <0.01) and 1.0, 1.6, 2.6, 2.7, and 1.8 (P for quadratic term <0.01), respectively. PBB-153 was also positively associated with the prevalence of metabolic syndrome with adjusted odds ratios of 1.0, 1.5, 3.1, 3.1, and 3.1 (P for trend<0.01). As in its association with diabetes, PBDE-153 showed an inverted U-shaped association with metabolic syndrome. CONCLUSIONS -- Pending confirmation in prospective studies, lipophilic xenobiotics, including brominated POPs stored in adipose tissue, may be involved in the pathogenesis of diabetes and metabolic syndrome. [ABSTRACT FROM AUTHOR]

Objective: To compare the prevalence of disordered eating and body dissatisfaction between adolescents with type 1 diabetes and a population-based sample of youth. Subjects: A clinic-based sample of 143 adolescents (73 male and 70 female) with type 1 diabetes who participated in the Assessing Health and Eating among Adolescents with Diabetes (AHEAD) study was compared with a population-based sample of 4746 youths (2377 male, 2357 female, and 12 missing) who participated in Project Eating Among Teens (Project EAT). Method: Participants completed surveys and anthropometric measurements of height and weight. Results: Although some adolescents with type 1 diabetes endorsed unhealthy weight control practices, overall, they reported less weight dissatisfaction and were less likely to use any unhealthy weight control behaviors and more likely to report regular meal consumption than the population-based sample. Females with type 1 diabetes were less likely to report dieting, fasting, or eating very little food to control weight during the past year than their population-based peers. However, males with type 1 diabetes were less likely than their peers to exercise and to consume more fruits and vegetables for healthy weight control. Of medical concern were insulin omission (1.4% males and 10.3% females) and dosage reduction (1.4% males and 7.4% females) as means of weight control among youth with type 1 diabetes. Conclusions: Despite medical supervision, some adolescents with type 1 diabetes reported unhealthy weight control behaviors and weight concerns, including insulin manipulation. Altering the insulin regimen may cause complications. All adolescents warrant attention for unhealthy behaviors and weight concerns. [ABSTRACT FROM AUTHOR]

OBJECTIVE -- Type 2 diabetes and periodontal disease are known to be associated, but the temporality of this relationship has not been firmly established. We investigated whether baseline periodontal disease independently predicts incident diabetes over two decades of follow-up. RESEARCH DESIGN AND METHODS -- A total of 9,296 nondiabetic male and female National Health and Nutrition Examination Survey (NHANES I) participants aged 25-74 years who completed a baseline dental examination (1971-1976) and had at least one follow-up evaluation (1982-1992) were studied. We defined six categories of baseline periodontal disease using the periodontal index. Of 7,168 dentate participants, 47% had periodontal index = 0 (periodontally healthy); the remaining were classified into periodontal index quintiles. Incident diabetes was defined by 1) death certificate (ICD-9 code 250), 2) self-report of diabetes requiring pharmacological treatment, or 3) health care facility stay with diabetes discharge code. Multivariable logistic regression models assessed incident diabetes odds across increasing levels of periodontal index in comparison with periodontally healthy participants. RESULTS -- The adjusted odds ratios (ORs) for incident diabetes in periodontal index categories 1 and 2 were not elevated, whereas the ORs in periodontal index categories 3 through 5 were 2.26 (95% CI 1.56-3.27), 1.71 (1.0-2.69), and 1.50 (0.99-2.27), respectively. The OR in edentulous participants was 1.30 (1.00-1.70). Dentate participants with advanced tooth loss had an OR of 1.70 (P < 0.05) relative to those with minimal tooth loss. CONCLUSIONS -- Baseline periodontal disease is an independent predictor of incident diabetes in the nationally representative sample of NHANES I. [ABSTRACT FROM AUTHOR]

OBJECTIVE -- We reported strong relations between serum concentrations of persistent organic pollutants (POPs), especially organochlorine (OC) pesticides or nondioxin-like polychlorinated biphenyls (PCBs), and prevalence of diabetes in a U.S population with background exposure to POPs. Here, we investigated POPs and insulin resistance, a frequent pathogenic precursor of type 2 diabetes. RESEARCH DESIGN AND METHODS -- Serum POPs and homeostasis model assessment of insulin resistance (HOMA-IR) were investigated cross-sectionally in 749 nondiabetic participants aged ≥20 years. Nineteen POPs in five subclasses were selected, detectable in ≥60% of participants. RESULTS -- Among subclasses, OC pesticides were most strongly associated with HOMA-IR. Adjusted geometric means of HOMA were 3.27, 3.36, 3.48, and 3.85 (P for trend <0.01) across quartiles of OC pesticides. The relationship strengthened with increasing HOMA-IR percentile: adjusted odds ratios comparing the highest versus lowest POPs quartile were 1.8 for being ≥50th percentile of HOMA-IR, 4.4 for being ≥75th percentile, and 7.5 for being ≥90th percentile. Associations with elevated HOMA-IR appeared to be specific to oxychlordane and trans-nonachlor but also were found for two nondioxin-like PCBs. No HOMA-IR associations were seen in the other three POP subclasses. The association between OC pesticides and HOMA-IR tended to strengthen as waist circumference increased, with no apparent association in the lowest quartile of OC pesticide concentrations. CONCLUSIONS -- These findings, coupled with those concerning diabetes prevalence, suggest that OC pesticides and nondioxin-like PCBs may be associated with type 2 diabetes risk by increasing insulin resistance, and POPs may interact with obesity to increase the risk of type 2 diabetes. [ABSTRACT FROM AUTHOR]

OBJECTIVE -- Low-level exposure to some persistent organic pollutants (POPs) has recently become a focus because of their possible link with the risk of diabetes. RESEARCH DESIGN AND METHODS -- Cross-sectional associations of the serum concentrations of POPs with diabetes prevalence were investigated in 2,016 adult participants in the National Health and Nutrition Examination Survey 1999-2002. Six POPs (2,2′,4,4′,5,5′ -hexachlorobiphenyl, 1,2,3,4,6,7,8-heptachlorodibenzo-p-dioxin, 1,2,3,4,6,7,8,9-octachlorodibenzo-p-dioxin, oxychlordane, p,p′-dichlorodiphenyltrichloroethane, and trans-nonachlor) were selected, because they were detectable in ≥80% of participants. RESULTS -- Compared with subjects with serum concentrations below the limit of detection, after adjustment for age, sex, race and ethnicity, poverty income ratio, BMI, and waist circumference, diabetes prevalence was strongly positively associated with lipid-adjusted serum concentrations of all six POPs. When the participants were classified according to the sum of category numbers of the six POPs, adjusted odds ratios were 1.0, 14.0, 14.7, 38.3, and 37.7 (P for trend < 0.001). The association was consistent in stratified analyses and stronger in younger participants, Mexican Americans, and obese individuals. CONCLUSIONS -- There were striking dose-response relations between serum concentrations of six selected POPs and the prevalence of diabetes. The strong graded association could offer a compelling challenge to future epidemiologic and toxicological research. [ABSTRACT FROM AUTHOR]

Smoking is associated with low serum carotenoid concentrations. Prospective studies have found lower diabetes risk among persons with high-carotenoid diets. Whether diabetes risk is low in the rare smoker who has high serum carotenoid levels is unknown. The authors investigated the interaction of serum carotenoid concentrations and smoking with diabetes mellitus in 4,493 Black and White men and women aged 18–30 years in the Coronary Artery Risk Development in Young Adults (CARDIA) Study. The authors assessed 15-year (1985–2001) incident diabetes (148 cases), insulin concentration, and insulin resistance (homeostasis model assessment) in smokers and nonsmokers according to baseline levels of serum α-carotene, β-carotene, zeaxanthin, β-cryptoxanthin, and lycopene. Diabetes incidence was inversely associated with the sum of carotenoid concentrations in nonsmokers (per standard deviation (SD) increase, relative hazard = 0.74, 95% confidence interval: 0.55, 0.99) but not in current smokers (relative hazard = 1.13, 95% confidence interval: 0.83, 1.53) (p for interaction = 0.02). Similarly, year 15 insulin and insulin resistance values, adjusted for baseline levels, were inversely related to sum of carotenoids only in nonsmokers (per SD increase in insulin level, slope = −0.46 (p = 0.03); per SD increase in insulin resistance, slope = −0.14 (p = 0.01)). In CARDIA, higher serum carotenoid concentrations are associated with lower risk of diabetes and insulin resistance in nonsmokers but not in smokers. [ABSTRACT FROM AUTHOR]

Serum gamma-glutamyltransferase (GGT) concentration, within its normal range, has recently been proposed as a reliable marker of oxidative stress. Oxidative stress plays a central pathogenic role in many metabolic and/or cardiovascular diseases, incidences of which have recently increased in South Korea. Since serum GGT has strong associations with these diseases and their risk factors, the authors hypothesized a corresponding secular trend of increasing serum GGT levels in South Korea. Study subjects were 8,072 male workers at a large steel company who were aged 2444 years at baseline and had received annual physical examinations from 1996 to 2003. The secular trend was a 0.1066-units/liter increase in ln(GGT) level per calendar year (a 180% increase during the 7-year follow-up period) (p < 0.01). Adjustment for body mass index, alcohol consumption, smoking, exercise, and cholesterol level as time-dependent covariates did not change the results. Although cholesterol is commonly used as a marker of epidemiologic transition, there was a less dramatic secular trend in ln(serum cholesterol) level, and it disappeared after adjustment for the secular trend in serum GGT. These findings suggest that serum GGT concentration can be used as a sensitive marker of epidemiologic transition, and they portend a continuing rise in incidences of metabolic and/or cardiovascular diseases in this population in the coming years. [ABSTRACT FROM AUTHOR]

Context: Low cardiorespiratory fitness is an established risk factor for cardiovascular and total mortality; however, mechanisms responsible for these associations are uncertain. Objective: To test whether low fitness, estimated by short duration on a maximal treadmill test, predicted the development of cardiovascular disease risk factors and whether improving fitness (increase in treadmill test duration between examinations) was associated with risk reduction. Design, Setting, and Participants: Population-based longitudinal cohort study of men and women 18 to 30 years of age in the Coronary Artery Risk Development in Young Adults (CARDIA) study. Participants who completed the treadmill examination according to the Balke protocol at baseline were followed up from 1985-1986 to 2000-2001. A subset of participants (n = 2478) repeated the exercise test in 1992-1993. Main Outcome Measures: Incident type 2 diabetes, hypertension, the metabolic syndrome (defined according to National Cholesterol Education Program Adult Treatment Panel III), and hypercholesterolemia (low-density lipoprotein cholesterol ≥160 mg/dL [4.14 mmol/L]). Results: During the 15-year study period, the rates of incident diabetes, hypertension, the metabolic syndrome, and hypercholesterolemia were 2.8, 13.0, 10.2, and 11.7 per 1000 person-years, respectively. After adjustment for age, race, sex, smoking, and family history of diabetes, hypertension, or premature myocardial infarction, participants with low fitness (<20th percentile) were 3- to 6-fold more likely to develop diabetes, hypertension, and the metabolic syndrome than participants with high fitness (≥60th percentile), all P<.001. Adjusting for baseline body mass index diminished the strength of these associations to 2-fold (all P<.001). In contrast, the association between low fitness and hypercholesterolemia was modest (hazard ratio [HR], 1.4; 95% confidence interval [CI], 1.1-1.7; P = .02) and attenuated to marginal significance after body mass index adjustment (P = .13). Improved fitness over 7 years was associated with a reduced risk of developing diabetes (HR, 0.4; 95% CI, 0.2-1.0; P = .04) and the metabolic syndrome (HR, 0.5; 95% CI, 0.3-0.7; P<.001), but the strength and significance of these associations was reduced after accounting for changes in weight. Conclusions: Poor fitness in young adults is associated with the development of cardiovascular disease risk factors. These associations involve obesity and may be modified by improving fitness. [ABSTRACT FROM AUTHOR]

Objective: We investigated whether autonomic nervous system dysfunction, estimated by slow heart rate recovery (HRR) following cessation of an exercise treadmill test, was associated with increases in insulin and glucose over time and the development of type 2 diabetes.Research Design and Methods: Maximal exercise tests were performed by 3295 healthy adults aged 18-30 years in the Coronary Artery Risk Development in Young Adults (CARDIA) study. Repeat measurements of insulin and glucose collected at 7-, 10-, and 15-year examinations were compared by quartiles of HRR (maximum heart rate minus heart rate 2 min after cessation of the test). Incident diabetes was identified at any follow-up examination as glucose >or=7 mmol/l or the use of diabetes control medication.Results: Among participants who did not develop diabetes, fasting insulin concentrations increased from baseline to year 15. Following adjustment (for age, race, sex, smoking status, and BMI), participants with the slowest HRR (quartile 1) had higher fasting insulin at each examination than participants with faster HRR (e.g., year 15 examination: 88.1 vs. 81.3 pmol/l for quartile 1 vs. quartile 4, respectively, P = 0.05). Glucose did not differ by quartile of HRR at any examination. Among participants with poor fitness, the risk of developing diabetes (n = 98) was 3.4-fold greater (95% CI 1.5-8.0) when HRR was <42 vs. >42 bpm. This persisted following adjustment for baseline insulin.Conclusions: Autonomic dysfunction, in combination with poor physical fitness, may be a mechanism associated with early glucose dysmetabolism and the development of diabetes. [ABSTRACT FROM AUTHOR]

OBJECTIVE--To examine the prospective association between accordance with the 2005 Dietary Guidelines for Americans (DGA) and subsequent diabetes incidence and changes in cardiometabolic risk factors. RESEARCH DESIGN AND METHODS--The sample consisted of 4,381 black and white young adults examined repeatedly from 1985 to 2005. We used the 2005 Diet Quality Index (DQI) to rate participants' diets based on meeting key dietary recommendations conveyed by the 2005 DGA. RESULTS--Overall, we found no association between DQI score and diabetes risk using Cox models adjusted for potential confounders. Higher DQI scores were associated with favorable changes in HDL cholesterol and blood pressure overall (P for trend <0.05), but with increased insulin resistance among blacks (P for trend <0.01). CONCLUSIONS--Our findings highlight the need for evaluation of the DGA's effectiveness, particularly among ethnic minority populations. Clinicians should be aware that following the DGA might not lower diabetes risk. [ABSTRACT FROM AUTHOR]

The article focuses on a study on the association between serum concentrations of persistent organic pollutants (POPs) and diabetes. It revealed that most POPs belonging to POP subclasses were positively associated with the prevalence of diabetes. Polychlorinated dibenzofurans (PCDFs) are said to have a weak association with diabetes. The analysis of the study showed that dioxin-like polychlorinated biphenyls (BCPs) and organoclorine (OC) pesticide were the most strongly linked with the disease.

Focuses on the effect of wheat bran supplement on the metabolism of patients with type 2 diabetes. Body weight; Fasting blood glucose; C-reactive protein.

Metabolic syndrome (MetS), Type 2 diabetes (T2D), and cardiovascular disease (CVDI share an inflammatory etiology and are known to be influenced by diet. We investigated associations of hypothesized prooxidative (Fe) and antioxidative (Zn, Mg, β-carotene, vitamin C, vitamin E) micronutrients with incident MetS, T2D, and CVD in the Multi-Ethnic Study of Atherosclerosis. Participants, 45-84 y at baseline (2000-2002), were followed through 2010. Diet was assessed by FFQ. After adjusting for demographics and behavioral confounders, including BMI, dietary vitamin E intake was inversely associated with incident MetS and CVD [HR for extreme quintiles: MetS = 0.78 195% Cl = 0.62, 0.97), P-trend = 0.01; CVD: HR = 0.69 (95% Cl = 0.46, 1.031, P-trend = 0.04]. Intakes of heme iron and Zn from red meat, but not from other sources, were positively associated with risk of MetS theme iron from red meat: HR = 1.25 (95% Cl = 0.99,1.56), P-trend = 0.03; Zn from red meat: HR = 1.29 (95% Cl = 1.03,1.61), P-trend = 0.04] and CVD ]heme iron from red meat: HR = 1.65 (95% Cl = 1.10,2.47), P-trend = 0.01; Zn from red meat: HR = 1.51(95% Cl = 1.02, 2.24), P-trend = 0.01]. Dietary intakes of nonheme iron, Mg, vitamin C, and β-carotene were not associated with risk of MetS, T2D, or CVD. Data provided little support for the associations between specific micronutrients and MetS, T2D, or CVD. However, nutrients consumed in red meat, or red meat as a whole, may increase risk of MetS and CVD. [ABSTRACT FROM AUTHOR]

Objective. To determine whether several personal or lifestyle risk factors for the occurrence of endometrial cancer are also risk factors for death following endometrial cancer.Methods. In 1986, we obtained risk factor information by mail on 41,836 women aged 55–69 years and living in Iowa. We followed those initially free of cancer through 2000 and identified incident endometrial cancers via linkage to a cancer registry. Women with endometrial cancer (n = 415) then were followed to identify overall and endometrial cancer deaths.Results. Over a median of 6.4 years following endometrial cancer diagnosis, 93 women died, 39 with endometrial cancer as the underlying cause. Among the various personal and lifestyle risk factors examined, only diabetes (self-reported) was related to death following endometrial cancer. Adjusted for age and extent of endometrial cancer at diagnosis, the relative risk of overall death for diabetic versus nondiabetic women was 2.79 (95% CI 1.63–4.78). For endometrial cancer as a specific cause of death, the diabetes-related relative risk was 2.38 (95% CI 1.05–5.37). Further adjustment for tumor grade strengthened these relative risks slightly.Conclusions. Diabetes is associated with poorer survival after incident endometrial cancer, independent of tumor stage and grade. Our findings raise the possibility of a diabetes-related condition, such as hyperglycemia or hyperinsulinemia, contributing to poorer endometrial cancer survival. [Copyright &y& Elsevier]