@article {1210, title = {Association between adiposity in midlife and older age and risk of diabetes in older adults.}, journal = {JAMA}, volume = {303}, year = {2010}, month = {2010 Jun 23}, pages = {2504-12}, abstract = {

CONTEXT: Adiposity is a well-recognized risk factor for type 2 diabetes among young and middle-aged adults, but the relationship between body composition and type 2 diabetes is not well described among older adults.

OBJECTIVE: To examine the relationship between adiposity, changes in adiposity, and risk of incident type 2 diabetes in adults 65 years of age and older.

DESIGN, SETTING, AND PARTICIPANTS: Prospective cohort study (1989-2007) of 4193 men and women 65 years of age and older in the Cardiovascular Health Study. Measures of adiposity were derived from anthropometry and bioelectrical impedance data at baseline and anthropometry repeated 3 years later.

MAIN OUTCOME MEASURE: Incident diabetes was ascertained based on use of antidiabetic medication or a fasting glucose level of 126 mg/dL or greater.

RESULTS: Over median follow-up of 12.4 years (range, 0.9-17.8 years), 339 cases of incident diabetes were ascertained (7.1/1000 person-years). The adjusted hazard ratio (HR) (95\% confidence interval [CI]) of type 2 diabetes for participants in the highest quintile of baseline measures compared with those in the lowest was 4.3 (95\% CI, 2.9-6.5) for body mass index (BMI [calculated as weight in kilograms divided by height in meters squared]), 3.0 (95\% CI, 2.0-4.3) for BMI at 50 years of age, 4.2 (95\% CI, 2.8-6.4) for weight, 4.0 (95\% CI, 2.6-6.0) for fat mass, 4.2 (95\% CI, 2.8-6.2) for waist circumference, 2.4 (95\% CI, 1.6-3.5) for waist-hip ratio, and 3.8 (95\% CI, 2.6-5.5) for waist-height ratio. However, when stratified by age, participants 75 years of age and older had HRs approximately half as large as those 65 to 74 years of age. Compared with weight-stable participants (+/-2 kg), those who gained the most weight from 50 years of age to baseline (> or = 9 kg), and from baseline to the third follow-up visit (> or = 6 kg), had HRs for type 2 diabetes of 2.8 (95\% CI, 1.9-4.3) and 2.0 (95\% CI, 1.1-3.7), respectively. Participants with a greater than 10-cm increase in waist size from baseline to the third follow-up visit had an HR of type 2 diabetes of 1.7 (95\% CI, 1.1-2.8) compared with those who gained or lost 2 cm or less.

CONCLUSION: Among older adults, overall and central adiposity, and weight gain during middle age and after the age of 65 years are associated with risk of diabetes.

}, keywords = {Adiposity, Age Factors, Aged, Body Mass Index, Diabetes Mellitus, Type 2, Female, Humans, Incidence, Male, Prospective Studies, Risk Factors, United States, Weight Gain}, issn = {1538-3598}, doi = {10.1001/jama.2010.843}, author = {Biggs, Mary L and Mukamal, Kenneth J and Luchsinger, Jos{\'e} A and Ix, Joachim H and Carnethon, Mercedes R and Newman, Anne B and de Boer, Ian H and Strotmeyer, Elsa S and Mozaffarian, Dariush and Siscovick, David S} } @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 {5849, title = {Adiposity and cognitive decline in the cardiovascular health study.}, journal = {Neuroepidemiology}, volume = {40}, year = {2013}, month = {2013}, pages = {274-81}, abstract = {

BACKGROUND: Studies relating adiposity to cognition in the elderly show conflicting results, which may be explained by the choice of adiposity measures. Thus, we studied the longitudinal associations of different adiposity measures, fat mass by bioelectrical impedance analysis, body mass index (BMI) and waist circumference (WC), with cognitive performance in the Cardiovascular Health Study.

METHODS: Cognitive performance was assessed with the modified Mini-Mental State Examination, the Digit Symbol Substitution Test, and a composite of both. We used linear mixed models to estimate rates of change in cognitive function scores associated with adiposity measured at baseline.

RESULTS: The final sample was comprised of 2,681 women (57.9\%) and 1,949 men (42.1\%) aged 73 {\textpm} 5.2 and 73.9 {\textpm} 5.6 years, respectively. Adiposity was associated with slower cognitive decline in most analyses. Results were similar for fat mass, BMI and WC. Higher fat-free mass was also related to slower cognitive decline. Results were similar in analyses excluding persons with cancer, smokers, and persons with short follow-up, poor self-reported health, or persons with cardiovascular disease.

CONCLUSIONS: Higher adiposity and higher fat-free mass in the elderly was related to better cognitive performance. This finding was not explained by confounding by preexisting conditions.

}, keywords = {Adiposity, Aged, Aged, 80 and over, Body Mass Index, Cardiovascular Diseases, Cognition Disorders, Electric Impedance, Female, Humans, Male, Risk Factors, Waist Circumference, Waist-Hip Ratio}, issn = {1423-0208}, doi = {10.1159/000345136}, author = {Luchsinger, Jos{\'e} A and Biggs, Mary L and Kizer, Jorge R and Barzilay, Joshua and Fitzpatrick, Annette and Newman, Anne and Longstreth, William T and Lopez, Oscar and Siscovick, David and Kuller, Lewis} } @article {6062, title = {Circulating 25-hydroxyvitamin D is associated with insulin resistance cross-sectionally but not longitudinally in older adults: The Cardiovascular Health Study.}, journal = {Metabolism}, volume = {62}, year = {2013}, month = {2013 Dec}, pages = {1788-94}, abstract = {

BACKGROUND: Despite extensive study, the role of vitamin D in insulin resistance and secretion remains unclear.

OBJECTIVE: To examine the cross-sectional and longitudinal relationships between 25-hydroxyvitamin D (25(OH)D) concentrations and indices of insulin resistance and secretion in older adults.

METHODS AND RESULTS: Among 2134 participants of the Cardiovascular Health Study who were free from cardiovascular disease, we measured serum 25(OH)D concentrations in samples collected in 1992-1993. We examined insulin resistance and secretion using Homeostasis Model Assessment (HOMA) estimates cross-sectionally and among 1469 participants who had repeated HOMA measures four years later (1996-1997). In cross-sectional analysis, each 10 ng/mL increment in 25(OH)D concentration was associated with a 0.09 lower adjusted HOMA-IR [95\% CI (-0.17, -0.02), p=0.01]. However, baseline 25(OH)D concentrations were not associated with change in HOMA-IR over 4 years of follow up (p=0.48). 25(OH)D concentrations were not associated with insulin secretion, as determined by HOMA-β, in either cross-sectional or longitudinal analysis.

CONCLUSIONS: Circulating 25(OH)D concentrations are associated with lower insulin resistance in cross-sectional but not longitudinal analyses. Whether this reflects residual confounding in cross-sectional analyses or the short-term nature of the relationship between vitamin D and insulin sensitivity will require trials with repeated measures of these factors.

}, keywords = {Adiposity, Aged, Anthropometry, Cardiovascular Diseases, Cross-Sectional Studies, Exercise, Female, Humans, Hydroxycholecalciferols, Inflammation, Insulin, Insulin Resistance, Longitudinal Studies, Male, Middle Aged, Obesity, Risk Factors, Surveys and Questionnaires}, issn = {1532-8600}, doi = {10.1016/j.metabol.2013.07.008}, author = {Danziger, John and Biggs, Mary L and Niemi, Matt and Ix, Joachim H and Kizer, Jorge R and Djouss{\'e}, Luc and de Boer, Ian H and Siscovick, David S and Kestenbaum, Bryan and Mukamal, Kenneth J} }