Review of methods for measuring ß-cell function: Design considerations from the Restoring Insulin Secretion (RISE) Consortium.

The Restoring Insulin Secretion (RISE) study was initiated to evaluate interventions to slow or reverse the progression of ß-cell failure in type 2 diabetes (T2D). To design the RISE study, we undertook an evaluation of methods for measurement of ß-cell function and changes in ß-cell function in response to interventions. In the present paper, we review approaches for measurement of ß-cell function, focusing on methodologic and feasibility considerations. Methodologic considerations included: (1) the utility of each technique for evaluating key aspects of ß-cell function (first- and second-phase insulin secretion, maximum insulin secretion, glucose sensitivity, incretin effects) and (2) tactics for incorporating a measurement of insulin sensitivity in order to adjust insulin secretion measures for insulin sensitivity appropriately. Of particular concern were the capacity to measure ß-cell function accurately in those with poor function, as is seen in established T2D, and the capacity of each method for demonstrating treatment-induced changes in ß-cell function. Feasibility considerations included: staff burden, including time and required methodological expertise; participant burden, including time and number of study visits; and ease of standardizing methods across a multicentre consortium. After this evaluation, we selected a 2-day measurement procedure, combining a 3-hour 75-g oral glucose tolerance test and a 2-stage hyperglycaemic clamp procedure, augmented with arginine.

HEMOGLOBIN A1C, BLOOD PRESSURE, AND LDL-CHOLESTEROL CONTROL AMONG HISPANIC/LATINO ADULTS WITH DIABETES: RESULTS FROM THE HISPANIC COMMUNITY HEALTH STUDY/STUDY OF LATINOS (HCHS/SOL).

OBJECTIVE: To determine the prevalence of Hispanic/Latino adults with diabetes who meet target hemoglobin A1c, blood pressure (BP), and low-density-lipoprotein cholesterol (LDL-C) recommendations, and angiotensin-converting enzyme (ACE) inhibitors/angiotensin receptor blocker (ARB) and statin medication use by heritage and sociodemographic and diabetes-related characteristics. METHODS: Data were cross-sectional, collected between 2008 and 2011, and included adults age 18 to 74 years who reported a physician diagnosis of diabetes in the Hispanic Community Health Study/Study of Latinos (N = 2,148). Chi-square tests compared the prevalence of hemoglobin A1c, BP, and LDL-C targets and ACE/ARB and statin use across participant characteristics. Predictive margins regression was used to determine the prevalence adjusted for sociodemographic characteristics. RESULTS: The overall prevalence of A1c <7.0% (53 mmol/mol), BP <130/80 mm Hg, and LDL-C <100 mg/dL was 43.0, 48.7, and 36.6%, respectively, with 8.4% meeting all three targets. Younger adults aged 18 to 39 years with diabetes were less likely to have A1c <7.0% (53 mmol/mol) or LDL-C <100 mg/dL compared to those aged 65 to 74 years; younger adults were more likely to have BP <130/80 mm Hg (P<.05 for all). Individuals of Mexican heritage were significantly less likely to have A1c <7.0% (53 mmol/mol) compared to those with Cuban heritage, but they were more likely to have BP <130/80 mm Hg compared to those with Dominican, Cuban, or Puerto Rican heritage (P<.05 for all); there was no difference in LDL-C by heritage. Overall, 38.2% of adults with diabetes were taking a statin, and 50.5% were taking ACE/ARB medications. CONCLUSION: Hemoglobin A1c, BP, and LDL-C control are suboptimal among Hispanic/Latinos with diabetes living in the U.S. With 8.4% meeting all three recommendations, substantial opportunity exists to improve diabetes control in this population. ABBREVIATIONS: A1c = hemoglobin A1c; ABC = hemoglobin A1c, blood pressure, low-density-lipoprotein cholesterol; ACE = angiotensin-converting enzyme; ADA = American Diabetes Association; ARB = angiotensin receptor blocker; BMI = body mass index; BP = blood pressure; CHD = coronary heart disease; CVD = cardiovascular disease; HCHS/SOL = Hispanic Community Health Study/Study of Latinos; LDL-C = low-density-lipoprotein cholesterol; NHANES = National Health and Nutrition Examination Survey; PAD = peripheral artery disease.

Detecting prediabetes among Hispanics/Latinos from diverse heritage groups: Does the test matter? Findings from the Hispanic Community Health Study/Study of Latinos.

The objectives of this analysis were to compare the ability of fasting plasma glucose (FPG), post oral load plasma glucose (2hPG), and hemoglobin A1c (HbA1c) to identify U.S. Hispanic/Latino individuals with prediabetes, and to assess its cardiovascular risk factor correlates. This is a cross-sectional analysis of baseline data from 15,507 adults without self-reported diabetes mellitus from six Hispanic/Latino heritage groups, enrolled in the Hispanic Community Health Study/Study of Latinos, which takes place in four U.S. communities. The prevalence of prediabetes was determined according to individual or combinations of ADA-defined cut points: FPG=5.6-7.0mmol/L, 2hPG=7.8-11.1mmol/L, and HbA1c=5.7%-6.4% (39-46mmol/mol). The sensitivity of these criteria to detect prediabetes was estimated. The prevalence ratios (PRs) for selected cardiovascular risk factors were compared among alternative categories of prediabetes versus normoglycemia [FPG<5.6mmol/L and 2hPG<7.8mmol/L and HbA1c<5.7% (39mmol/mol)]. Approximately 36% of individuals met any of the ADA prediabetes criteria. Using 2hPG as the gold standard, the sensitivity of FPG was 40.1%, HbA1c was 45.6%, and that of HbA1c+FPG was 62.2%. The number of significant PRs for cardiovascular risk factors was higher among individuals with isolated 2hPG=7.8-11.1mmol/L, FPG=5.6-7.0mmol/L+HbA1c=5.7%-6.4%, or those who met the three prediabetes criteria. Assessing FPG, HbA1c, and cardiovascular risk factors in Hispanics/Latinos at risk might enhance the early prevention of diabetes mellitus and cardiovascular complications in this young and growing population, independent of their heritage group.

IDENTIFYING PROBABLE DIABETES MELLITUS AMONG HISPANICS/LATINOS FROM FOUR U.S. CITIES: FINDINGS FROM THE HISPANIC COMMUNITY HEALTH STUDY/STUDY OF LATINOS.

OBJECTIVE: The aim of this study was to compare the ability of American Diabetes Association (ADA) diagnostic criteria to identify U.S. Hispanics/Latinos from diverse heritage groups with probable diabetes mellitus and assess cardiovascular risk factor correlates of those criteria. METHODS: Cross-sectional analysis of data from 15,507 adults from 6 Hispanic/Latino heritage groups, enrolled in the Hispanic Community Health Study/Study of Latinos. The prevalence of probable diabetes mellitus was estimated using individual or combinations of ADA-defined cut points. The sensitivity and specificity of these criteria at identifying diabetes mellitus from ADA-defined prediabetes and normoglycemia were evaluated. Prevalence ratios of hypertension, abnormal lipids, and elevated urinary albumin-creatinine ratio for unrecognized diabetes mellitus-versus prediabetes and normoglycemia-were calculated. RESULTS: Among Hispanics/Latinos (mean age, 43 years) with diabetes mellitus, 39.4% met laboratory test criteria for probable diabetes, and the prevalence varied by heritage group. Using the oral glucose tolerance test as the gold standard, the sensitivity of fasting plasma glucose (FPG) and hemoglobin A1c-alone or in combination-was low (18, 23, and 33%, respectively) at identifying probable diabetes mellitus. Individuals who met any criterion for probable diabetes mellitus had significantly higher (P<.05) prevalence of most cardiovascular risk factors than those with normoglycemia or prediabetes, and this association was not modified by Hispanic/Latino heritage group. CONCLUSION: FPG and hemoglobin A1c are not sensitive (but are highly specific) at detecting probable diabetes mellitus among Hispanics/Latinos, independent of heritage group. Assessing cardiovascular risk factors at diagnosis might prompt multitarget interventions and reduce health complications in this young population. ABBREVIATIONS: 2hPG = 2-hour post-glucose load plasma glucose ADA = American Diabetes Association BMI = body mass index CV = cardiovascular FPG = fasting plasma glucose HbA1c = hemoglobin A1c HCHS/SOL = Hispanic Community Health Study/Study of Latinos HDL-C = high-density-lipoprotein cholesterol NGT = normal glucose tolerance NHANES = National Health and Nutrition Examination Survey OGTT = oral glucose tolerance test TG = triglyceride UACR = urine albumin-creatinine ratio.

Arginine is preferred to glucagon for stimulation testing of ß-cell function.

A key aspect of research into the prevention and treatment of type 2 diabetes is the availability of reproducible clinical research methodology to assess ß-cell function. One commonly used method employs nonglycemic secretagogues like arginine (arg) or glucagon (glgn). This study was designed to quantify the insulin response to arg and glgn and determine test repeatability and tolerability. Obese overnight-fasted subjects with normal glucose tolerance were studied on 4 separate days: twice using arg (5 g iv) and twice with glgn (1 mg iv). Pre- and postinfusion samples for plasma glucose, insulin, and C-peptide were acquired. Arg and glgn challenges were repeated in the last 10 min of a 60-min glucose (900 mg/min) infusion. Insulin and C-peptide secretory responses were estimated under baseline fasting glucose conditions (AIRarg and AIRglgn) and hyperglycemic (AIRargMAX AIRglgnMAX) states. Relative repeatability was estimated by intraclass correlation coefficient (ICC). Twenty-three (12 men and 11 women) subjects were studied (age: 42.4 ± 8.3 yr; BMI: 31.4 ± 2.8 kg/m²). Geometric means (95% CI) for baseline-adjusted values AIRarg and AIRglgn were 84 (75-95) and 102 (90-115) µU/ml, respectively. After the glucose infusion, AIRargMAX and AIRglgnMAX were 395 (335-466) and 483 (355-658) µU/ml, respectively. ICC values were >0.90 for AIRarg andAIRargMAX. Glucagon ICCs were 0.83, 0.34, and 0.36, respectively, although the exclusion of one outlier increased the latter two values (to 0.84 and 0.86). Both glgn and arg induced mild adverse events that were transient. Glucagon, but not arginine, induced moderate adverse events due to nausea. Taken together, arginine is preferred to glucagon for assessment of ß-cell function.

Durable change in glycaemic control following intensive management of type 2 diabetes in the ACCORD clinical trial.

AIMS/HYPOTHESIS: We aimed to determine the persistence of glycaemic control 1 year after a limited period of intensive glycaemic management of type 2 diabetes. METHODS: 4119 ACCORD Trial participants randomised to target HbA1c <6.0% (42 mmol/mol) for 4.0 ± 1.2 years were systematically transitioned to target HbA1c 7.0-7.9% (53-63 mmol/mol) and followed for an additional 1.1 ± 0.2 years. Characteristics of participants with HbA1c <6.5% (48 mmol/mol) or ≥6.5% at transition were compared. Changes in BMI and glucose-lowering medications were compared between those ending with HbA1c <6.5% vs ≥6.5%. Poisson models were used to assess the independent effect of attaining HbA1c <6.5% before transition on ending with HbA1c <6.5%. RESULTS: Participants with pre-transition HbA1c <6.5% were older with shorter duration diabetes and took less insulin but more non-insulin glucose-lowering agents than those with higher HbA1c. A total of 823 participants achieved a final HbA1c <6.5%, and had greater post-transition reductions in BMI, insulin dose and secretagogue and acarbose use than those with higher HbA1c (p < 0.0001). HbA1c <6.5% at transition predicted final HbA1c <6.5% (crude RR 4.9 [95% CI 4.0, 5.9]; RR 3.9 [95% CI 3.2, 4.8] adjusted for demographics, co-interventions, pre-intervention HbA1c, BMI and glucose-lowering medication, and post-transition change in both BMI and glucose-lowering medication). Progressively lower pre-transition HbA1c levels were associated with a greater likelihood of maintaining a final HbA1c of <6.5%. Follow-up duration was not associated with post-transition rise in HbA1c. CONCLUSIONS/INTERPRETATION: Time-limited intensive glycaemic management using a combination of agents that achieves HbA1c levels below 6.5% in established diabetes is associated with glycaemic control more than 1 year after therapy is relaxed.

Hemoglobin A1c, fasting plasma glucose, and 2-hour plasma glucose distributions in U.S. population subgroups: NHANES 2005-2010.

PURPOSE: Although mean concentrations of hemoglobin A1c (A1C), fasting plasma glucose, and 2-hour plasma glucose differ by demographics, it is unclear what other characteristics of the distributions may differ, such as the amount of asymmetry of the distribution (skewness) and shift left or right compared with another distribution (shift). METHODS: Using kernel density estimation, we created smoothed plots of the distributions of fasting plasma glucose (N = 7250), 2-hour plasma glucose (N = 5851), and A1C (N = 16,209) by age, race-ethnicity, and sex in the 2005-2010 National Health and Nutrition Examination Survey, a nationally representative sample of U.S. adults including people with and without diabetes. We tested differences in distributions using cumulative logistic regression. RESULTS: The distributions were generally unimodal and right-skewed. All distributions were shifted higher and more right-skewed for older age groups (P < .001 for each marker). Compared with non-Hispanic whites, the distribution of fasting plasma glucose was shifted higher for Mexican-Americans (P = .01), whereas the distribution of A1C was shifted higher for non-Hispanic blacks (P < .001). The distribution of fasting plasma glucose was shifted higher for men (P < .001) and the distribution of 2-hour plasma glucose was shifted higher for women (P = .01). CONCLUSIONS: We provide a graphic reference for comparing these distributions and diabetes cut-points by demographic factors.

Early-adulthood cardiovascular disease risk factor profiles among individuals with and without diabetes in the Framingham Heart Study.

OBJECTIVE: Many studies of diabetes have examined risk factors at the time of diabetes diagnosis instead of considering the lifetime burden of adverse risk factor levels. We examined the 30-year cardiovascular disease (CVD) risk factor burden that participants have up to the time of diabetes diagnosis. RESEARCH DESIGN AND METHODS: Among participants free of CVD, incident diabetes cases (fasting plasma glucose ≥ 126 mg/dL or treatment) occurring at examinations 2 through 8 (1979-2008) of the Framingham Heart Study Offspring cohort were age- and sex-matched 1:2 to controls. CVD risk factors (hypertension, high LDL cholesterol, low HDL cholesterol, high triglycerides, obesity) were measured at the time of diabetes diagnosis and at time points 10, 20, and 30 years prior. Conditional logistic regression was used to compare risk factor levels at each time point between diabetes cases and controls. RESULTS: We identified 525 participants with new-onset diabetes who were matched to 1,049 controls (mean age, 60 years; 40% women). Compared with those without diabetes, individuals who eventually developed diabetes had higher levels of hypertension (odds ratio [OR], 2.2; P = 0.003), high LDL (OR, 1.5; P = 0.04), low HDL (OR, 2.1; P = 0.0001), high triglycerides (OR, 1.7; P = 0.04), and obesity (OR, 3.3; P < 0.0001) at time points 30 years before diabetes diagnosis. After further adjustment for BMI, the ORs for hypertension (OR, 1.9; P = 0.02) and low HDL (OR, 1.7; P = 0.01) remained statistically significant. CONCLUSIONS: CVD risk factors are increased up to 30 years before diagnosis of diabetes. These findings highlight the importance of a life course approach to CVD risk factor identification among individuals at risk for diabetes.

The association between symptomatic, severe hypoglycaemia and mortality in type 2 diabetes: retrospective epidemiological analysis of the ACCORD study.

OBJECTIVE: To determine whether there is a link between hypoglycaemia and mortality among participants in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial. DESIGN: Retrospective epidemiological analysis of data from the ACCORD trial. Setting Diabetes clinics, research clinics, and primary care clinics. PARTICIPANTS: Patients were eligible for the ACCORD study if they had type 2 diabetes, a glycated haemoglobin (haemoglobin A(1C)) concentration of 7.5% or more during screening, and were aged 40-79 years with established cardiovascular disease or 55-79 years with evidence of subclinical disease or two additional cardiovascular risk factors. Intervention Intensive (haemoglobin A(1C) <6.0%) or standard (haemoglobin A(1C) 7.0-7.9%) glucose control. OUTCOME MEASURES: Symptomatic, severe hypoglycaemia, manifest as either blood glucose concentration of less than 2.8 mmol/l (<50 mg/dl) or symptoms that resolved with treatment and that required either the assistance of another person or medical assistance, and all cause and cause specific mortality, including a specific assessment for involvement of hypoglycaemia. RESULTS: 10 194 of the 10 251 participants enrolled in the ACCORD study who had at least one assessment for hypoglycaemia during regular follow-up for vital status were included in this analysis. Unadjusted annual mortality among patients in the intensive glucose control arm was 2.8% in those who had one or more episodes of hypoglycaemia requiring any assistance compared with 1.2% for those with no episodes (53 deaths per 1924 person years and 201 deaths per 16 315 person years, respectively; adjusted hazard ratio (HR) 1.41, 95% CI 1.03 to 1.93). A similar pattern was seen among participants in the standard glucose control arm (3.7% (21 deaths per 564 person years) v 1.0% (176 deaths per 17 297 person years); adjusted HR 2.30, 95% CI 1.46 to 3.65). On the other hand, among participants with at least one hypoglycaemic episode requiring any assistance, a non-significantly lower risk of death was seen in those in the intensive arm compared with those in the standard arm (adjusted HR 0.74, 95% 0.46 to 1.23). A significantly lower risk was observed in the intensive arm compared with the standard arm in participants who had experienced at least one hypoglycaemic episode requiring medical assistance (adjusted HR 0.55, 95% CI 0.31 to 0.99). Of the 451 deaths that occurred in ACCORD up to the time when the intensive treatment arm was closed, one death was adjudicated as definitely related to hypoglycaemia. CONCLUSION: Symptomatic, severe hypoglycaemia was associated with an increased risk of death within each study arm. However, among participants who experienced at least one episode of hypoglycaemia, the risk of death was lower in such participants in the intensive arm than in the standard arm. Symptomatic, severe hypoglycaemia does not appear to account for the difference in mortality between the two study arms up to the time when the ACCORD intensive glycaemia arm was discontinued. TRIAL REGISTRATION: NCT00000620.

The effects of baseline characteristics, glycaemia treatment approach, and glycated haemoglobin concentration on the risk of severe hypoglycaemia: post hoc epidemiological analysis of the ACCORD study.

OBJECTIVES: To investigate potential determinants of severe hypoglycaemia, including baseline characteristics, in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial and the association of severe hypoglycaemia with levels of glycated haemoglobin (haemoglobin A(1C)) achieved during therapy. DESIGN: Post hoc epidemiological analysis of a double 2x2 factorial, randomised, controlled trial. SETTING: Diabetes clinics, research clinics, and primary care clinics. PARTICIPANTS: 10 209 of the 10 251 participants enrolled in the ACCORD study with type 2 diabetes, a haemoglobin A(1C) concentration of 7.5% or more during screening, and aged 40-79 years with established cardiovascular disease or 55-79 years with evidence of significant atherosclerosis, albuminuria, left ventricular hypertrophy, or two or more additional risk factors for cardiovascular disease (dyslipidaemia, hypertension, current smoker, or obese). Interventions Intensive (haemoglobin A(1C) <6.0%) or standard (haemoglobin A(1C) 7.0-7.9%) glucose control. MAIN OUTCOME MEASURES: Severe hypoglycaemia was defined as episodes of "low blood glucose" requiring the assistance of another person and documentation of either a plasma glucose less than 2.8 mmol/l (<50 mg/dl) or symptoms that promptly resolved with oral carbohydrate, intravenous glucose, or glucagon. RESULTS: The annual incidence of hypoglycaemia was 3.14% in the intensive treatment group and 1.03% in the standard glycaemia group. We found significantly increased risks for hypoglycaemia among women (P=0.0300), African-Americans (P<0.0001 compared with non-Hispanic whites), those with less than a high school education (P<0.0500 compared with college graduates), aged participants (P<0.0001 per 1 year increase), and those who used insulin at trial entry (P<0.0001). For every 1% unit decline in the haemoglobin A(1C) concentration from baseline to 4 month visit, there was a 28% (95% CI 19% to 37%) and 14% (4% to 23%) reduced risk of hypoglycaemia requiring medical assistance in the standard and intensive groups, respectively. In both treatment groups, the risk of hypoglycaemia requiring medical assistance increased with each 1% unit increment in the average updated haemoglobin A(1C) concentration (standard arm: hazard ratio 1.76, 95% CI 1.50 to 2.06; intensive arm: hazard ratio 1.15, 95% CI 1.02 to 1.21). CONCLUSIONS: A greater drop in haemoglobin A(1C) concentration from baseline to the 4 month visit was not associated with an increased risk for hypoglycaemia. Patients with poorer glycaemic control had a greater risk of hypoglycaemia, irrespective of treatment group. Identification of baseline subgroups with increased risk for severe hypoglycaemia can provide guidance to clinicians attempting to modify patient therapy on the basis of individual risk. TRIAL REGISTRATION: ClinicalTrials.gov number NCT00000620.

Trends in cardiovascular disease risk factors in individuals with and without diabetes mellitus in the Framingham Heart Study.

BACKGROUND: Individuals with diabetes mellitus are at 2- to 3-fold increased risk for cardiovascular disease (CVD) relative to those without diabetes. Our objective was to examine CVD risk factor level changes among individuals with and without type 2 diabetes mellitus from 1970 to 2005 in the Framingham Heart Study. METHODS AND RESULTS: We included 4195 participants (3990 with no diabetes and 205 with diabetes) 50 years of age and 3495 participants (3178 with no diabetes and 317 with diabetes) 60 years of age. Contemporaneous CVD risk factor levels were measured; linear regression models were used to assess the interaction between diabetes status and calendar year on CVD risk factor levels. Among 50-year-olds without diabetes mellitus, there was an increase in body mass index of 0.39 kg/m(2) per 10 years, whereas for those with diabetes, there was an increase of 2.52 kg/m(2) (P value for the diabetes-by-calendar year interaction [P for interaction] <0.001). For low-density lipoprotein cholesterol, the mean decrease was -7.43 mg/dL per decade (nondiabetes) and -15.5 mg/dL for diabetes (P for interaction=0.002). For systolic blood pressure, the mean decrease was -3.35 mm Hg per decade (nondiabetes) and -3.50 mm Hg for diabetes (P for interaction=0.97). The direction of the trends for those with diabetes relative to those without diabetes was similar for 60-year-olds. CONCLUSIONS: Compared with individuals without diabetes mellitus, individuals with diabetes experienced a greater increase in body mass index, a greater decrease in low-density lipoprotein cholesterol, and a similar magnitude of decline in systolic blood pressure. Individuals with diabetes mellitus have not experienced the necessary declines in CVD risk factors to overcome their increased risk of CVD. Further efforts are needed to aggressively control CVD risk factors among individuals with diabetes mellitus.

Trends in all-cause and cardiovascular disease mortality among women and men with and without diabetes mellitus in the Framingham Heart Study, 1950 to 2005.

BACKGROUND: Despite population declines in all-cause mortality, women with diabetes mellitus may have experienced an increase in mortality rates compared with men. METHODS AND RESULTS: We examined change in all-cause, cardiovascular, and non-cardiovascular disease mortality rates among Framingham Heart Study participants who attended examinations during an "earlier" (1950 to 1975; n=930 deaths) and a "later" (1976 to 2001; n=773 deaths) time period. Diabetes mellitus was defined as casual glucose > or =200 mg/dL, fasting plasma glucose > or =126 mg/dL, or treatment. Among women, the hazard ratios (HRs) for all-cause mortality in the later versus the earlier time period were 0.59 (95% confidence interval, 0.50 to 0.70; P<0.0001) for those without diabetes mellitus and 0.48 (95% confidence interval, 0.32 to 0.71; P=0.002) for those with diabetes mellitus. Similar results were observed in men. Among women and men, the HR of cardiovascular disease mortality declined among those with and without diabetes mellitus. Non-cardiovascular disease mortality declined among women without diabetes mellitus (HR, 0.76; P=0.01), whereas no change was observed among women with diabetes mellitus or among men with or without diabetes mellitus. Individuals with versus those without diabetes mellitus were at increased risk of all-cause mortality in the earlier (HR, 2.44; P<0.0001) and later (HR, 1.95; P<0.0001) time periods. CONCLUSIONS: Reductions in all-cause mortality among women and men with diabetes mellitus have occurred over time. However, mortality rates among individuals with diabetes mellitus remain approximately 2-fold higher compared with individuals without diabetes mellitus.

The association of plasma fibrinogen concentration with diabetic microvascular complications in young adults with early-onset of type 2 diabetes.

AIMS: Diabetic nephropathy is an important risk factor for cardiovascular diseases (CVD). The underlying etiology is not fully understood but may be related to changes in inflammatory and hemostatic markers with kidney disease. We investigated the associations of the markers with microvascular complications in Pima Indians (PI) with early-onset type 2 diabetes (T2DM). METHODS: C-reactive protein, interleukine-6, fibrinogen, D-dimer, plasmin-antiplasmin complex and plasminogen activator inhibitor-1 were measured in 104 PI (age: 32+/-4 y) with diabetes and 59 (32+/-4 y) with fasting glucose <110 mg/dl and 2-h glucose <140 mg/dl. Urine albumin to creatinine ratio (ACR) was used as marker of nephropathy. Severity of retinopathy was classified in the worse eye by direct ophthalmoscopy as none, background and proliferative. RESULTS: Of these markers, only fibrinogen was associated with ACR (r=0.25, p<0.01). After adjustment for age, sex, percentage Pima heritage, smoking status, diabetes duration, blood pressure and use of aspirin, antihypertensive and antihyperglycemic agents, general linear models (with natural log-transformed values of fibrinogen and ACR as dependent and independent variables, respectively) revealed that a one percent increase in ACR would yield a 0.02% increase in the fibrinogen (beta=0.02, p<0.05). Plasma fibrinogen was also significantly increased with severity of diabetic retinopathy (p<0.05). CONCLUSIONS: Increased plasma fibrinogen concentration was associated with diabetic microvascular disease, in particular with nephropathy. This may help to explain the etiologic link between nephropathy and CVD.

Increasing cardiovascular disease burden due to diabetes mellitus: the Framingham Heart Study.

BACKGROUND: Marked reductions in cardiovascular disease (CVD) morbidity and mortality have occurred in the United States over the last 50 years. We tested the hypothesis that the relative burden of CVD attributable to diabetes mellitus (DM) has increased over the past 5 decades. METHODS AND RESULTS: Participants aged 45 to 64 years from the Framingham Heart Study, who attended examinations in an "early" time period (1952 to 1974), were compared with those who attended examinations in a later time period (1975 to 1998). The risk of CVD events (n=133 among those with and 1093 among those without DM) attributable to DM in the 2 time periods was assessed with Cox proportional hazards models; population attributable risk of DM as a CVD risk factor was calculated for each time period. The age- and sex-adjusted hazard ratio for DM as a CVD risk factor was 3.0 (95% CI, 2.3 to 3.9) in the earlier time period and 2.5 (95% CI, 1.9 to 3.2) in the later time period. The population attributable risk for DM as a CVD risk factor increased from 5.4% (95% CI, 3.8% to 6.9%) in the earlier time period to 8.7% (95% CI, 5.9% to 11.4%) in the later time period (P for attributable risk ratio=0.04), although multivariable adjustment resulted in attenuation of these findings (P=0.12); most of these observations were found among men. CONCLUSIONS: The proportion of CVD attributable to DM has increased over the past 50 years in Framingham. These findings emphasize the need for increased efforts to prevent DM and to aggressively treat and control CVD risk factors among those with DM.

Metabolic syndrome and cardiovascular disease in older people: The cardiovascular health study.

OBJECTIVES: To assess the prospective association between metabolic syndrome (MetS) and cardiovascular disease (CVD) in older people and to evaluate the effect of lowering the threshold for impaired fasting glucose (IFG) on the prevalence of IFG and MetS and the risk of CVD. DESIGN: Prospective cohort study. SETTING: Four field centers in U.S. communities. PARTICIPANTS: Three thousand five hundred eighty-five subjects in the Cardiovascular Health Study free of diabetes mellitus and CVD at baseline (mean age 72, 62% female, 14% black). MEASUREMENTS: Baseline measures of MetS components and adjudicated incident CVD events. MetS (2001) was defined first using the original criteria from the Third Adult Treatment Panel Report of the National Cholesterol Education Program (> or =3 of the following: large waist circumference (women >88 cm, men >102 cm), elevated triglycerides (> or =1.70 mmol/L), low high-density lipoprotein cholesterol (men <1.04 mmol/L, women <1.30 mmol/L), elevated fasting glucose (6.1-6.9 mmol/L), and high blood pressure (> or =130/85 mmHg or self-reported use of medications for hypertension). Subjects were also classified according to the revised definition of the MetS (2005) that applies the lower threshold for fasting glucose (5.6-6.9 mmol/L). RESULTS: During follow-up (median 11 years), 818 coronary heart disease (CHD), 401 stroke, and 554 congestive heart failure (CHF) events occurred. Age- and race-adjusted hazard ratios (HRs) for CHD, stroke, and CHF were 1.30 (95% confidence interval (CI) = 1.07-1.57), 0.94 (95% CI = 0.73-1.21), and 1.40 (95% CI = 1.12-1.76) for women and 1.35 (95% CI = 1.10-1.66), 1.51 (95% CI = 1.08-2.12), and 1.47 (95% CI = 1.14-1.90) for men, respectively. Overall, women and men with MetS (2005) were 20% to 30% more likely to experience any CVD event than subjects without MetS (2005). Using the lower cut-point for IFG resulted in a near tripling in IFG prevalence (16% to 46%) and an additional 9% classified with MetS (2005) but HRs similar to those estimated from the original MetS (2001) criteria. High blood pressure was the component most strongly associated with incident CHD. CONCLUSION: Results from this study of an elderly, population-based cohort provide support for earlier investigations in primarily middle-aged populations that link the presence of MetS with the development of CVD and further underscore the importance of recognizing and treating its individual components, particularly high blood pressure.

Magnesium intake and incidence of metabolic syndrome among young adults.

BACKGROUND: Studies suggest that magnesium intake may be inversely related to risk of hypertension and type 2 diabetes mellitus and that higher intake of magnesium may decrease blood triglycerides and increase high-density lipoprotein (HDL) cholesterol levels. However, the longitudinal association of magnesium intake and incidence of metabolic syndrome has not been investigated. METHODS AND RESULTS: We prospectively examined the relations between magnesium intake and incident metabolic syndrome and its components among 4637 Americans, aged 18 to 30 years, who were free from metabolic syndrome and diabetes at baseline. Metabolic syndrome was diagnosed according to the National Cholesterol Education Program/Adult Treatment Panel III definition. Diet was assessed by an interviewer-administered quantitative food frequency questionnaire, and magnesium intake was derived from the nutrient database developed by the Minnesota Nutrition Coordinating Center. During the 15 years of follow-up, 608 incident cases of the metabolic syndrome were identified. Magnesium intake was inversely associated with incidence of metabolic syndrome after adjustment for major lifestyle and dietary variables and baseline status of each component of the metabolic syndrome. Compared with those in the lowest quartile of magnesium intake, multivariable-adjusted hazard ratio of metabolic syndrome for participants in the highest quartile was 0.69 (95% confidence interval [CI], 0.52 to 0.91; P for trend <0.01). The inverse associations were not materially modified by gender and race. Magnesium intake was also inversely related to individual component of the metabolic syndrome and fasting insulin levels. CONCLUSIONS: Our findings suggest that young adults with higher magnesium intake have lower risk of development of metabolic syndrome.