14 research outputs found
Association of Sleep Apnea, Diagnosed by Self-Reported Physician Diagnosis or Hospital Discharge Codes, With Atrial Fibrillation and Ectopy Using Ambulatory Electrocardiogram in the ARIC Study
Sleep apnea is associated with cardiac arrhythmias1 such as atrial fibrillation (AF), premature ventricular contractions (PVC), and premature atrial contractions (PAC). Mechanisms that may explain this association include autonomic imbalance, hypertension, intermittent hypoxia, and atrial remodeling. However, prior studies of sleep apnea and cardiac arrhythmias relied on a single ten second,12-lead electrocardiogram, and/or hospital medical records, which would miss paroxysmal, asymptomatic, and intermittent arrhythmias. The Reveal XT-SA study reported that using a medically implanted device for cardiac monitoring in patients with severe obstructive SA may help to identify newly detected AF, however application of this study’s findings to our work was limited as the Reveal XT-SA study used a small sample size in a clinical population.4 Our study overcomes these limitations by adding standardized 48-hour continuous ambulatory ECG (aECG) monitoring to the population-based Atherosclerosis Risk in Communities (ARIC) study to examine the association between sleep apnea and AF, PACs, and PVCs
Reducing the Population Burden of Coronary Heart Disease by Modifying Adiposity: Estimates From the ARIC Study
Background: Excess adiposity, which affects 69% of US adults, increases coronary heart disease (CHD) risk in an association that manifests below conventional obesity cut points. The population-level impact on CHD risk that is attainable through modest adiposity reductions in populations is not well characterized. We estimated the effect of hypothetical reductions in both body mass index (BMI) and waist circumference (WC) on CHD incidence. Methods and Results: The study population included 13 610 ARIC (Atherosclerosis Risk in Communities) participants. Our hypothetical reduction in BMI or WC was applied relative to the temporal trend, with no hypothetical reduction among those with BMI >24 or WC >88 cm, respectively. This threshold for hypothetical reduction is near the clinical guidelines for excess adiposity. CHD risk differences compared the hypothetical reduction with no reduction. Sensitivity analysis was conducted to estimate the effect of applying the hypothetical BMI reduction at the established overweight cut point of 25. Cumulative 12-year CHD incidence with no intervention was 6.3% (95% CI, 5.9–6.8%). Risk differences following the hypothetical BMI and WC reductions were −0.6% (95% CI, −1.0% to −0.1%) and −1.0% (95% CI, −1.4% to −0.5%), respectively. These results were robust for the sensitivity analyses. Consequently, we estimated that this hypothetical reduction of 5% in BMI and WC, respectively, could have prevented 9% and 16%, respectively, of the CHD events occurring in this study population over 12 years, after adjustment for established CHD risk factors. Conclusions: Meaningful CHD risk reductions could derive from modest reductions in adiposity attainable through lifestyle modification
“What are food and air like inside our bodies?”: Children’s thinking about digestion and respiration
Multiple stages of aqueous alteration along fractures in mudstone and sandstone strata in Gale Crater, Mars
Curiosity at Gale Crater, Mars: Characterization and analysis of the rocknest sand shadow
The Rocknest aeolian deposit is similar to aeolian features analyzed by the Mars Exploration Rovers (MERs) Spirit and Opportunity. The fraction of sand <150 micrometers in size contains ~55% crystalline material consistent with a basaltic heritage and ~45% x-ray amorphous material. The amorphous component of Rocknest is iron-rich and silicon-poor and is the host of the volatiles (water, oxygen, sulfur dioxide, carbon dioxide, and chlorine) detected by the Sample Analysis at Mars instrument and of the fine-grained nanophase oxide component first described from basaltic soils analyzed by MERs. The similarity between soils and aeolian materials analyzed at Gusev Crater, Meridiani Planum, and Gale Crater implies locally sourced, globally similar basaltic materials or globally and regionally sourced basaltic components deposited locally at all three locations
Institutional adaptation: Demands for management reform and university administration
Higher education organizations around the world have always faced environmental changes. However, in the past decade altered societal expectations, new public policies, and technological innovations have created an unprecedented set of challenges for universities. Although the borders of universities have opened in new ways for thei