@article {5860, title = {Hemoglobin A1c and arterial and ventricular stiffness in older adults.}, journal = {PLoS One}, volume = {7}, year = {2012}, month = {2012}, pages = {e47941}, abstract = {

OBJECTIVE: Arterial and ventricular stiffening are characteristics of diabetes and aging which confer significant morbidity and mortality; advanced glycation endproducts (AGE) are implicated in this stiffening pathophysiology. We examined the association between HbA(1c), an AGE, with arterial and ventricular stiffness measures in older individuals without diabetes.

RESEARCH DESIGN \& METHODS: Baseline HbA(1c) was measured in 830 participants free of diabetes defined by fasting glucose or medication use in the Cardiovascular Health Study, a population-based cohort study of adults aged >= 65 years. We performed cross-sectional analyses using baseline exam data including echocardiography, ankle and brachial blood pressure measurement, and carotid ultrasonography. We examined the adjusted associations between HbA(1c) and multiple arterial and ventricular stiffness measures by linear regression models and compared these results to the association of fasting glucose (FG) with like measures.

RESULTS: HbA(1c) was correlated with fasting and 2-hour postload glucose levels (r = 0.21; p<0.001 for both) and positively associated with greater body-mass index and black race. In adjusted models, HbA(1c) was not associated with any measure of arterial or ventricular stiffness, including pulse pressure (PP), carotid intima-media thickness, ankle-brachial index, end-arterial elastance, or left ventricular mass (LVM). FG levels were positively associated with systolic, diastolic and PP and LVM.

CONCLUSIONS: In this sample of older adults without diabetes, HbA(1c) was not associated with arterial or ventricular stiffness measures, whereas FG levels were. The role of AGE in arterial and ventricular stiffness in older adults may be better assessed using alternate AGE markers.

}, keywords = {Adult, African Continental Ancestry Group, Aged, Ankle Brachial Index, Arteries, Blood Glucose, Blood Pressure, Body Mass Index, Cross-Sectional Studies, Fasting, Female, Genetic Association Studies, Glycated Hemoglobin A, Glycation End Products, Advanced, Heart Ventricles, Humans, Male, Middle Aged, Ultrasonography, Vascular Stiffness}, issn = {1932-6203}, doi = {10.1371/journal.pone.0047941}, author = {Zieman, Susan J and Kamineni, Aruna and Ix, Joachim H and Barzilay, Joshua and Djouss{\'e}, Luc and Kizer, Jorge R and Biggs, Mary L and de Boer, Ian H and Chonchol, Michel and Gottdiener, John S and Selvin, Elizabeth and Newman, Anne B and Kuller, Lewis H and Siscovick, David S and Mukamal, Kenneth J} } @article {6400, title = {Potassium and glucose measures in older adults: the Cardiovascular Health Study.}, journal = {J Gerontol A Biol Sci Med Sci}, volume = {70}, year = {2015}, month = {2015 Feb}, pages = {255-61}, abstract = {

BACKGROUND: We sought to determine the impacts of serum and dietary potassium measures on glucose metabolism and diabetes risk in older adults.

METHODS: Among participants of the Cardiovascular Health Study, a community-based cohort of older American adults, we examined a) cross-sectional associations between potassium and measures of insulin sensitivity and secretion estimated from oral glucose tolerance tests and b) longitudinal associations of serum and dietary potassium with diabetes risk.

RESULTS: Among 4,754 participants aged >=65 years at baseline, there were 445 cases of incident diabetes during a median follow-up of 12 years. In multivariate models, baseline serum and dietary potassium were both associated with lower insulin sensitivity and greater insulin secretion. Compared with those with a serum potassium >=4.5 mEq/L, participants with a serum potassium <4.0mEq/L had an adjusted mean difference in Matsuda insulin sensitivity index of -0.18 (-0.39, 0.02). Compared with those in the highest quartile, participants in the lowest quartile of dietary potassium intake had a corresponding adjusted mean difference in Matsuda insulin sensitivity index of -0.61 (-0.94, -0.29). In multivariate models, neither serum nor dietary potassium intake was associated with long-term diabetes risk.

CONCLUSIONS: Although we did not identify serum and dietary potassium as risk factors for incident diabetes in older adults, results from cross-sectional analyses suggest that both may be associated with increased insulin resistance. This relationship with insulin resistance needs to be confirmed, and its importance on diabetes risk, cardiovascular risk, and conditions specific to older adults should be determined as well.

}, keywords = {Aged, Blood Glucose, Cohort Studies, Cross-Sectional Studies, Diabetes Mellitus, Female, Humans, Insulin, Insulin Resistance, Longitudinal Studies, Male, Multivariate Analysis, Potassium, Potassium, Dietary, Risk Factors, United States}, issn = {1758-535X}, doi = {10.1093/gerona/glu071}, author = {Chatterjee, Ranee and Biggs, Mary L and de Boer, Ian H and Brancati, Frederick L and Svetkey, Laura P and Barzilay, Joshua and Djouss{\'e}, Luc and Ix, Joachim H and Kizer, Jorge R and Siscovick, David S and Mozaffarian, Dariush and Edelman, David and Mukamal, Kenneth J} }