Racial Differences in Atrial Fibrillation Prevalence and Left Atrial Size - Corrected Proof

2010-03-12

Abstract: Background: Previous studies relying on clinical care data have suggested that atrial fibrillation is less common in African Americans than Caucasians, but the mechanism remains unknown. Clinical care may itself vary by race, potentially affecting the accuracy of atrial fibrillation ascertainment in studies relying on clinical data. We sought to examine racial differences in atrial fibrillation prevalence determined by protocol-driven electrocardiograms (ECGs) obtained in prospective cohort studies and to study racial differences in echocardiographic characteristics.Methods: We pooled primary data from 3 cohort studies with atrial fibrillation adjudicated from study protocol ECGs and documentation of potentially important confounders: the Heart and Soul Study (n=1014), the Heart and Estrogen-Progestin Replacement Study (n=2673), and The Osteoporotic Fractures in Men Sleep Study (n=2911). Left atrial anatomic dimensions were compared among races from sinus rhythm echocardiograms in the Heart and Soul Study.Results: Of the 6611 participants, 268 (4%) had atrial fibrillation: Caucasians had the highest prevalence (5%), and African Americans had the lowest (1%; P<.001 for each compared with all other races). After adjustment for potential confounders, Caucasians had a 3.8-fold greater odds of having atrial fibrillation than African Americans (95% confidence interval, 1.6-8.8, P=.002). Although ventricular and atrial volumes and function were similar in Caucasians and African Americans, Caucasians had a 2 mm larger anterior-posterior left atrial diameter after adjusting for potential confounders (95% confidence interval, 1-3 mm, P<.001).Conclusion: ECG confirmed atrial fibrillation is more common in Caucasians than in African Americans, which might be related to the larger left atrial diameter observed in Caucasians.

Long-acting Beta-Agonists with and without Inhaled Corticosteroids and Catastrophic Asthma Events - Corrected Proof

Shelley R. Salpeter, Andrew J. Wall, Nicholas S. Buckley — 2010-02-22

Abstract: Background: It is unclear whether long-acting β-agonists with concomitant inhaled corticosteroids increase asthma-related intubations and deaths. We pooled data on long-acting β-agonists with variable and concomitant inhaled corticosteroids to evaluate the risk for catastrophic asthma events.Methods: We conducted searches of electronic databases, the US Food and Drug Administration website, clinical-trials registries, and selected references through December 2008. We analyzed randomized controlled trials in patients with asthma, which lasted at least 3 months, evaluated long-acting β-agonists compared with placebo or long-acting β-agonists with inhaled corticosteroids compared with corticosteroids alone, and included at least 1 catastrophic event, defined as asthma-related intubation or death.Results: In pooled trial data that included 36,588 participants, long-acting β-agonists increased catastrophic events 2-fold (Peto odds ratio [OR] 2.10; 95% confidence interval [CI], 1.37-3.22). Statistically significant increases were seen for long-acting β-agonists with variable corticosteroids compared with placebo (OR 1.83; 95% CI, 1.14-2.95) and for concomitant treatment with corticosteroids compared with corticosteroids alone (OR 3.65; 95% CI, 1.39-9.55). Similar increases in risk were seen for variable and concomitant corticosteroid use, salmeterol and formoterol, and children and adults. When the analysis was restricted to trials with controlled corticosteroid use, given as part of the study intervention, concomitant treatment still increased catastrophic events compared with corticosteroids alone (OR 8.19; 95% CI, 1.10-61.18).Conclusion: Long-acting β-agonists increase the risk for asthma-related intubations and deaths, even when used in a controlled fashion with concomitant inhaled corticosteroids.

The American Journal of Medicine - Articles in Press

Racial Differences in Atrial Fibrillation Prevalence and Left Atrial Size - Corrected Proof

Long-acting Beta-Agonists with and without Inhaled Corticosteroids and Catastrophic Asthma Events - Corrected Proof