@article {1254, title = {Measures of adiposity and future risk of ischemic stroke and coronary heart disease in older men and women.}, journal = {Am J Epidemiol}, volume = {173}, year = {2011}, month = {2011 Jan 01}, pages = {10-25}, abstract = {

The relation between measures of general and central adiposity and individual cardiovascular endpoints remains understudied in older adults. This study investigated the association of measures of body size and composition with incident ischemic stroke or coronary heart disease (1989-2007) in 3,754 community-dwelling US adults aged 65-100 years. Standardized anthropometry and bioelectric impedance measurements were obtained at baseline. Body mass index at age 50 years (BMI50) was calculated on the basis of recalled weight. Although only waist/hip ratio was significantly associated with ischemic stroke in quintile analysis in women, dichotomized body mass index (BMI) (>= 30 kg/m{\texttwosuperior}) was the only significant predictor in men. For coronary heart disease, there were significant positive adjusted associations for all adiposity measures, without interaction by sex. This was true for both quintiles and conventional cutpoints for obesity, although BMI-defined overweight (25-29.9 kg/m{\texttwosuperior} was significant at midlife but not at baseline. Strengths of association for extreme quintiles (quintile 5 vs. quintile 1) were broadly comparable, but the highest effect estimates were for waist/hip ratio (hazard ratio = 1.56, 95\% confidence interval: 1.25, 1.94) and BMI50 (hazard ratio = 1.71, 95\% confidence interval: 1.37, 2.14), both of which remained significant after adjustment for mediators, BMI, or each other. Whether these differences translate to better risk prediction will require meta-analytical approaches, as will determination of prognostic cutpoints.

}, keywords = {Adiposity, Age Factors, Aged, Aged, 80 and over, Brain Ischemia, Coronary Disease, Female, Humans, Incidence, Male, Middle Aged, Obesity, Prevalence, Retrospective Studies, Risk Factors, Sex Factors, United States}, issn = {1476-6256}, doi = {10.1093/aje/kwq311}, author = {Kizer, Jorge R and Biggs, Mary L and Ix, Joachim H and Mukamal, Kenneth J and Zieman, Susan J and de Boer, Ian H and Mozaffarian, Dariush and Barzilay, Joshua I and Strotmeyer, Elsa S and Luchsinger, Jos{\'e} A and Elkind, Mitchell S V and Longstreth, W T and Kuller, Lewis H and Siscovick, David S} } @article {7123, title = {Measures of Body Size and Composition and Risk of Incident Atrial Fibrillation in Older People: The Cardiovascular Health Study.}, journal = {Am J Epidemiol}, volume = {183}, year = {2016}, month = {2016 Jun 1}, pages = {998-1007}, abstract = {

Various anthropometric measures, including height, have been associated with atrial fibrillation (AF). This raises questions about the appropriateness of using ratio measures such as body mass index (BMI), which contains height squared in its denominator, in the evaluation of AF risk. Among older adults, the optimal anthropometric approach to risk stratification of AF remains uncertain. Anthropometric and bioelectrical impedance measures were obtained from 4,276 participants (mean age = 72.4 years) free of cardiovascular disease in the Cardiovascular Health Study. During follow-up (1989-2008), 1,050 cases of AF occurred. BMI showed a U-shaped association, whereas height, weight, waist circumference, hip circumference, fat mass, and fat-free mass were linearly related to incident AF. The strongest adjusted association occurred for height (per each 1-standard-deviation increment, hazard ratio = 1.38, 95\% confidence interval: 1.25, 1.51), which exceeded all other measures, including weight (hazard ratio = 1.21, 95\% confidence interval: 1.13, 1.29). Combined assessment of log-transformed weight and height showed regression coefficients that departed from the 1 to -2 ratio inherent in BMI, indicating a loss of predictive information. Risk estimates for AF tended to be stronger for hip circumference than for waist circumference and for fat-free mass than for fat mass, which was explained largely by height. These findings highlight the prominent role of body size and the inadequacy of BMI as determinants of AF in older adults.

}, issn = {1476-6256}, doi = {10.1093/aje/kwv278}, author = {Karas, Maria G and Yee, Laura M and Biggs, Mary L and Djouss{\'e}, Luc and Mukamal, Kenneth J and Ix, Joachim H and Zieman, Susan J and Siscovick, David S and Gottdiener, John S and Rosenberg, Michael A and Kronmal, Richard A and Heckbert, Susan R and Kizer, Jorge R} } @article {8539, title = {Metabolic Clusters and Outcomes in Older Adults: The Cardiovascular Health Study.}, journal = {J Am Geriatr Soc}, volume = {66}, year = {2018}, month = {2018 02}, pages = {289-296}, abstract = {

BACKGROUND/OBJECTIVES: Few studies have the requisite phenotypic information to define metabolic patterns that may inform our understanding of the pathophysiology and consequences of diabetes in older adults. We sought to characterize clusters of older adults on the basis of shared metabolic features.

DESIGN: Population-based prospective cohort study.

SETTING: Four U.S. Cardiovascular Health Study field centers.

PARTICIPANTS: Individuals aged 65 and older taking no glucose-lowering agents (N~=~2,231).

MEASUREMENTS: K-means cluster analysis of 11 metabolic parameters (fasting and postload serum glucose and plasma insulin, fasting C-peptide, body mass index, C-reactive protein (CRP), estimated glomerular filtration rate (eGFR), albuminuria, carboxymethyl lysine (an advanced glycation end-product), procollagen III N-terminal propeptide (a fibrotic marker)) and their associations with incident cardiovascular disease, diabetes, disability, and mortality over 8 to 14.5~years of follow-up and with measures of subclinical cardiovascular disease.

RESULTS: A 6-cluster solution provided robust differentiation into distinct, identifiable clusters. Cluster A (n~=~739) had the lowest glucose and insulin and highest eGFR and the lowest rates of all outcomes. Cluster B (n~=~419) had high glucose and insulin and intermediate rates of most outcomes. Cluster C (n~=~118) had the highest insulin. Cluster D (n~=~129) had the highest glucose with much lower insulin. Cluster E (n~=~314) had the lowest eGFR and highest albuminuria. Cluster F (n~=~512) had the highest CRP. Rates of CVD, mortality, and subclinical atherosclerosis were highest in clusters C, D, and E and were similar to rates in participants with treated diabetes. Incidence of disability was highest in Cluster C.

CONCLUSION: Clustering according to metabolic parameters identifies distinct phenotypes that are strongly associated with clinical and functional outcomes, even at advanced age.

}, keywords = {Aged, Aged, 80 and over, Blood Glucose, C-Reactive Protein, Cardiovascular Diseases, Diabetes Mellitus, Female, Glomerular Filtration Rate, Humans, Incidence, Insulin, Longitudinal Studies, Male, Prospective Studies, Risk Factors, United States}, issn = {1532-5415}, doi = {10.1111/jgs.15205}, author = {Mukamal, Kenneth J and Siscovick, David S and de Boer, Ian H and Ix, Joachim H and Kizer, Jorge R and Djouss{\'e}, Luc and Fitzpatrick, Annette L and Tracy, Russell P and Boyko, Edward J and Kahn, Steven E and Arnold, Alice M} }