Objective-The purpose of this study was to investigate the impact of age, sex, and hypertension (HTN) on aortic atherosclerotic burden using cardiovascular MRI (CMR) in a free-living longitudinally followed cohort. Methods and Results-1763 participants (829 M and 934 F; 38 to 88 years of age) of the Framingham Heart Study Offspring cohort underwent CMR of the thoracoabdominal aorta using an ECG-gated 2D T2-weighted black-blood sequence. Of these, 1726 subjects (96%) with interpretable CMR were characterized by sex, age-quartile, and presence or absence of HTN and clinical cardiovascular disease (CVD). Aortic plaque prevalence and volume increased with increasing age in both sexes. For the nonhypertensive (no-HTN) group, plaque was identified in 702 (46%) with greater prevalence in women than in men (PϽ0.006). HTN was associated with greater aortic plaque burden (PϽ0.02). The 200 subjects with clinical CVD had greater plaque burden than subjects without CVD (PϽ0.0001). Conclusions-In this free-living longitudinally followed cohort, subclinical aortic atherosclerosis was seen in nearly half of subjects and increased with advancing age. HTN was associated with increased aortic plaque burden. Among no-HTN subjects, women had greater plaque burden than men. These data suggest that subclinical atherosclerosis is more common in no-HTN women and emphasize the importance of focusing on preventive measures in both sexes. [2][3][4][5][6] and in such studies, HTN is associated with greater prevalence and extent of aortic and coronary atherosclerosis. 3,5,6 A growing body of evidence has linked subclinical coronary 7 and aortic 8 -10 atherosclerosis to increased risk for clinically overt CVD, suggesting that early diagnosis and treatment of atherosclerosis in the preclinical stage may reduce CVD sequelae such as myocardial infarction and stroke. However, beyond autopsy studies, our understanding of the relationship between age, sex, and HTN with aortic atherosclerotic burden is incomplete.There are several reports about the relationship between HTN and atherosclerosis. Carotid intima-media thickness (IMT) is greater in persons with HTN than nonhypertensive subjects, and the association between IMT and blood pressure parameters, particularly systolic blood pressure, was found to be independent of age and gender. 11-13 However, the influence of HTN on prevalence of aortic plaque burden in an adult population is unknown. Cardiovascular magnetic resonance (CMR) offers unique advantages for assessment of the aorta and quantification of atherosclerotic plaque burden 14 -17 including the lack of ionizing radiation, while providing highly reproducible measures of aortic anatomy and atherosclerosis. 18 We sought to determine the relationship of age, sex, and HTN with aortic atherosclerotic prevalence and burden using CMR in a longitudinally followed free-living community based cohort. Methods Study Population and Sample SelectionThe design of the Framingham Heart Study (FHS) has been detailed elsewhere. 19 Subjects considered for ...

Microbial Fe reduction is widely believed to be the primary mechanism of As release from aquifer sands in Bangladesh, but alternative explanations have been proposed. Long-term incubation studies using natural aquifer material are one way to address such divergent views. This study addresses two issues related to this approach: (1) the need for suitable abiotic controls and (2) the spatial variability of the composition of aquifer sands. Four sterilization techniques were examined using orange-colored Pleistocene sediment from Bangladesh and artificial groundwater over 8 months. Acetate (10 mM) was added to sacrificial vials before sterilization using either (1) 25 kGy of gamma irradiation, (2) three 1-h autoclave cycles, (3) a single addition of an antibiotic mixture at 1x or (4) 10x the typical dose, and (5) a 10 mM addition of azide. The effectiveness of sterilization was evaluated using two indicators of microbial Fe reduction, changes in diffuse spectral reflectance and leachable Fe(II)/Fe ratios, as well as changes in P-extractable As concentrations in the solid phase. A low dose of antibiotics was ineffective after 70 days, whereas autoclaving significantly altered groundwater composition. Gamma irradiation, a high dose of antibiotics, and azide were effective for the duration of the experiment.

INTRODUCTION: Visceral adipose tissue, such as epicardial fat, is metabolically active, and may portend increased risk for cardiovascular disease (CVD) compared to subcutaneous fat. Cardiovascular magnetic resonance (CMR) can accurately delineate fat, but data are sparse regarding the relationship of epicardial and subcutaneous fat burden to CVD in community-living adult women. METHODS: 957 women (aged 64± 8 years) in the Framingham Heart Study Offspring cohort, followed by serial examinations since 1974, underwent CMR on a 1.5-T Philips system using an ECG-gated cine SSFP sequence. Epicardial fat thickness (EFT) over the midlevel right ventricle was measured from a 4-chamber view. Suprasternal subcutaneous fat thickness (SFT) was measured at the main pulmonary artery level. We compared EFT and SFT between women with clinical CVD, documented by a physician endpoint committee (+CVD), vs. those without (noCVD) based on Cycle 7 (1998 –2002) clinical data. Differences were assessed by two-sample T-test; ANOVA was used to adjust for age, diabetes, hypertension and menopausal status. RESULTS: The +CVD group comprised 74 (8%) women who were older and more likely to be postmenopausal, diabetic and hypertensive than noCVD women (Table ). EFT was greater in +CVD (10.5 ± 5.1mm) vs. noCVD (8.6 ± 5.2mm) groups, p<0.003. This difference remained significant after adjusting for age, diabetes, hypertension and menopausal status (Table ). No difference in SFT or body mass index was observed between groups (p=NS). CONCLUSIONS: Women with history of clinical CVD have greater EFT than women without CVD, and this difference persists after adjustment for common cardiovascular risk factors. However, subcutaneous fat, as assessed by chest wall adiposity, did not differ between groups. EFT may be a useful marker for cardiovascular risk, and prospective investigation of the relationship between EFT and future risk for CVD is warranted.

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