CardioSource WorldNews August 2013 | Page 18

CLINICAL NEWS JOURNAL WRAP Kim Eagle, MD, and the editors of CardioSource present relevant articles from various journals Battle of the Sexes: When it comes to clinical outcomes in patients presenting with stable angina and any level of coronary artery disease (CAD), is the burden greater for women than men? Tara L. Sedlak, MD, from Vancouver General Hospital, and colleagues attempted to answer that question in a recent analysis of adults aged ?20 years in British Columbia, Canada, with stable angina who underwent coronary angiography. Patients were followed for a median of 1.9 years. Their analysis included data about demographics, clinical characteristics, outcomes, hospitalization admissions, cardiac procedures, and death. Who Experiences Better Outcomes with Stable Angina and CAD? The patient cohort (n = 13,695) was categorized according to presence of CAD: none (0% luminal narrowing), nonobstructive CAD (1–49% luminal narrowing), and obstructive CAD (?50% luminal narrowing). Hazard ratios for freedom from major adverse cardiac events (MACE)—including the combined endpoints of all-cause mortality, nonfatal acute MI, nonfatal stroke, and HF admissions—were the primary measures of interest in the study. Most of the patients had obstructive CAD, a minority had nonobstructive CAD, and 15% had no CAD; women were more likely to have no CAD. Women also had a significantly higher proportion of nonobstructive CAD compared with men. Interestingly, in this category, women were older, had more hypertension, and more cancer, but smoked less than men. Results from the study, published in the American Heart Journal, revealed that women with stable angina and nonobstructive CAD had the greatest risk for MACE within the first year of cardiac catheterization—amounting to three times higher risk than men. Nonobstructive CAD also contributed to a 2.55-fold higher risk of MACE than in women with no CAD. In contrast, men with nonobstructive CAD had a similar risk as men with no CAD (adjusted HR = 0.61). When HF was excluded from the MACE outcomes, however, the difference between genders among the nonobstructive group was no longer significant. In light of these findings, Sedlak et al. concluded, a prospective trial to examine the impact of medical therapy on MACE in patients with nonobstructive CAD is warranted. Aggressive risk factor prevention and management (particularly of controlling blood pressure among women) would potentially be an important means of reducing MACE among women with nonobstructive CAD, as well. Sedlak TL, Lee M, Izadnegahdar M, et al. Am Heart J. 2013;166:38-44. Any Relief from Atrial Fibrillation in Sight? Atrial fibrillation (AF) is the most common type of arrhythmia, and treatment of AF represents a significant health care burden for the estimated 2.66 million people who have it. In 2005, the estimated cost of AF was $6.65 billion per year, which included the costs of hospitalization, in- and outpatient physician care, and medications. The incidence of AF is known to increase with age, so as the US population ages, can we expect the incidence and prevalence of AF to continue to rise? To help answer this question, Susan Colilla, PhD, MPH, and colleagues from Global Health Economics and Outcomes Research in Princeton, New Jersey, reviewed a large health insurance claims database for the years 2001–2008. The database represented a geographically diverse 5% of the US population; the investigators used a progression model that included all diagnosed AF cases as well as those cases expected to be chronic in nature. Colilla et al. looked about 20 years into the future to 2030. By that time, they expect that AF incidence will double—from 1.2 million cases in 2010 to 2.6 million cases 20 years later. Prevalence, then, is projected to increase from 5.2 million cases in 2010 to 12.1 million cases in 2030. This represents an annual growth rate of 4.3% for prevalence and 4.6% for incidence. “Variability in future trends in AF incidence and recurrence rates has the greatest impact on the projected estimates of chronic AF prevalence,” the authors wrote in the article published in the American Journal of Cardiology. However, “it can be concluded that both incidence and prevalence of AF are likely to rise from 2010 to 2030, but there exists a wide range of uncertainty around the magnitude of future trends.” As AF becomes more common, the public health burden of AF may reach concerning levels by 2030, the authors noted, and more research is needed to investigate what factors may be contributing to this increasing trend—followed by means to mitigate them. Colilla S, Crow A, Petkun W, et al. Am J Cardiol. 2013 July 4. [Epub ahead of print] 16 CardioSource WorldNews August 2013 CSWN_Journal_Scan_8'13.indd 16 8/19/13 5:05 PM