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Background and Aims: Glycosylated hemoglobin (HbA(1c)) has been associated with incident cardiovascular disease (CVD), but the findings are inconsistent. We tested the hypothesis that HbA(1c) may be associated with an increased risk of death and cardiovascular mortality in older adults., Methods and Results: We evaluated the association between HbA(1c) with all-cause and cardiovascular mortality in 810 participants without a history of diabetes in a sub-study of the Cardiovascular Health Study (CHS), a community cohort study of individuals > or =65 years of age. Glycosylated hemoglobin was measured at baseline and all-cause and cardiovascular mortality was assessed during the follow-up period. The relation between baseline HbA(1c) and death was evaluated with multivariate Cox proportional hazards regression models. After a median follow-up of 14.2 years, 416 deaths were observed. The crude incidence rates of all-cause mortality across HbA(1c) groups were: 4.4% per year, 4.3% per year and 4.6% per year for tertile 1 (< or =5.6%), tertile 2 (5.61-6.20%) and tertile 3 (> or =6.21%), respectively. In unadjusted and fully adjusted analyses, baseline HbA(1c) was not associated with all-cause mortality and cardiovascular mortality (hazard ratio: 1.16 [95% confidence interval 0.91-1.47] and hazard ratio: 1.31 [95% confidence interval 0.90-1.93], respectively for the highest HbA(1c) tertile compared with the lowest)., Conclusion: These results suggest that HbA(1c) does not significantly predict all-cause and cardiovascular mortality in non-diabetic community-dwelling older adults., (Copyright 2009 Elsevier B.V. All rights reserved.)

Background: Although ongoing cohort studies offer a unique opportunity to apply existing information collected prospectively to further the scientific understanding of Parkinson's disease (PD), they typically have limited information for clinical diagnosis., Methods: We used combinations of self-report, International Classification of Diseases - 9th edition codes and antiparkinsonian medications to identify PD in the Cardiovascular Health Study. To determine whether the expected inverse association between smoking and PD is evident using our outcome definitions, we assessed baseline smoking characteristics for various definitions of PD., Results: We identified 60 cases with prevalent PD (1.0%; 95% confidence interval, CI = 0.8-1.3%) and 154 with incident PD by year 14. Clear associations were observed for current smokers (odds ratio, OR = 0.50; 95% CI = 0.26-0.95) and for those who smoked ≥50 pack-years (OR = 0.53; 95% CI = 0.29-0.96). Estimates for smoking were similar when ≥2 data sources were required. Estimates for self-report alone were attenuated towards null., Conclusions: Using multiple data sources to identify PD represents an alternative method of outcome identification in a cohort that would otherwise not be possible for PD research. Ongoing cohort studies can provide settings in which rapid replication and explorations of new hypotheses for PD are possible., (Copyright © 2010 S. Karger AG, Basel.)

Background: It is unclear whether measures of glycemic status beyond fasting glucose (FG) levels improve incident heart failure (HF) prediction in patients without history of diabetes mellitus (DM)., Methods and Results: The association of measures of glycemic status at baseline (including FG, oral glucose tolerance testing [OGTT], fasting insulin, hemoglobin A(1c) [HbA(1c)] levels, and homeostasis model assessment of insulin resistance [HOMA-IR] and insulin secretion [HOMA-B]) with incident HF, defined as hospitalization for new-onset HF, was evaluated in 2386 elderly participants without history of DM enrolled in the Health, Aging, and Body Composition Study (median age, 73 years; 47.6% men; 62.5% white, 37.5% black) using Cox models. After a median follow-up of 7.2 years, 185 (7.8%) participants developed HF. Incident HF rate was 10.7 cases per 1000 person-years with FG <100mg/dL, 13.1 with FG 100-125 mg/dL, and 26.6 with FG >or=126 mg/dL (P=.002; P=.003 for trend). In adjusted models (for body mass index, age, history of coronary artery disease and smoking, left ventricular hypertrophy, systolic blood pressure and heart rate [HR], and creatinine and albumin levels), FG was the strongest predictor of incident HF (adjusted HR per 10mg/dL, 1.10; 95% CI, 1.02-1.18; P=.009); the addition of OGTT, fasting insulin, HbA(1c), HOMA-IR, or HOMA-B did not improve HF prediction. Results were similar across race and gender. When only HF with left ventricular ejection fraction (LVEF) 40%, was considered (n=71), the association was weaker (HR per 10mg/dL, 1.05; 95% CI; 0.94-1.18; P=.41)., Conclusions: Fasting glucose is a strong predictor of HF risk in elderly without history of DM. Other glycemic measures provide no incremental prediction information.

Context: There is substantial variability across ethnic groups in the predisposition to obesity and associated metabolic abnormalities. Skeletal muscle fat has been identified as an important depot that increases with aging and may contribute to the development of diabetes., Objective: We tested whether men of African ancestry have greater calf intermuscular adipose tissue (IMAT), compared to Caucasian men, and whether IMAT is associated with type 2 diabetes (T2D)., Design: We measured fasting serum glucose, body mass index, total body fat by dual-energy x-ray absorptiometry, and calf skeletal muscle composition by quantitative computed tomography in 1105 Caucasian and 518 Afro-Caribbean men aged 65+., Results: Compared to Caucasian men, we found greater IMAT and lower sc adipose tissue in Afro-Caribbean men at all levels of total adiposity (P < 0.0001), including the subset of men matched on age and dual-energy x-ray absorptiometry total body fat percentage (P < 0.001). In addition, IMAT was 29 and 23% greater, whereas sc adipose tissue was 6 and 8% lower among Caucasian and Afro-Caribbean men with T2D, respectively, compared to men without T2D (P < 0.01). Observed differences in intermuscular and sc fat, both ethnic and between men with and without T2D, were independent of age, height, calf skeletal muscle and total adipose tissue, and lifestyle factors., Conclusions: Our analyses suggest that despite lower total adiposity, skeletal muscle fat infiltration is greater among African than among Caucasian ancestry men and is associated with T2D in both ethnic groups. Additional studies are needed to determine the mechanisms contributing to ethnic differences in skeletal muscle adiposity and to define the metabolic and health implications of this fat depot.