Hindawi Publishing Corporation Cardiovascular Psychiatry and Neurology Volume 2012, Article ID 402079, 7 pages doi:10.1155/2012/402079 Clinical Study Sleep Apnea and Cognitive Function in Heart Failure Krysten M. Knecht, 1 Michael L. Alosco, 1 Mary Beth Spitznagel, 1, 2 Ronald Cohen, 3 Naftali Raz, 4 Lawrence Sweet, 3 Lisa H. Colbert, 5 Richard Josephson, 6 Joel Hughes, 1, 2 Jim Rosneck, 2 and John Gunstad 1, 2 1 Department of Psychology, Kent State University, Kent, OH 44242, USA 2 Department of Psychiatry, Summa Health System, Akron, OH 44304, USA 3 Institute for Brain Sciences, Brown University, Providence, RI 02912, USA 4 Institute of Gerontology, Wayne State University, Detroit, MI 48201, USA 5 Institute on Aging, University of Wisconsin—Madison, Madison, WI 53706, USA 6 Harrington Heart & Vascular Institute, University Hospitals Case Medical Center and Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA Correspondence should be addressed to John Gunstad, jgunstad@kent.edu Received 20 January 2012; Revised 13 April 2012; Accepted 16 April 2012 Academic Editor: Heimo Viinamaki Copyright © 2012 Krysten M. Knecht et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Background. Prior research indicates that heart failure (HF) patients exhibit significant cognitive deficits on neuropsychological testing. Sleep apnea is associated with both HF and reduced cognitive function, but the combined impact of these conditions on cognitive function is unknown. Methods. In the current study, 172 older adults with a dual diagnosis of HF and sleep apnea or HF alone completed a battery of cognitive tests measuring attention, executive functioning, and memory. Results. Relative to patients with HF alone, persons with both HF and sleep apnea performed worse on measures of attention after adjusting for demographic and medical variables. Conclusions. The current findings suggest that HF patients with comorbid sleep apnea may be at greater risk for cognitive impairment relative to HF patient without such history. Further work is needed to clarify mechanisms for these findings and to determine whether the interactive effects on cognitive function lead to poorer patient outcomes. 1. Introduction The American Heart Association estimates that heart failure (HF) affects more than five million adults and costs an estimated $30 billion annually in the United States alone [1]. As the population of older adults and the frequency of HF risk factors (e.g., hypertension and obesity) continue to rise, it is estimated that one in five adults will develop HF during their lifetime [1]. While the prevalence of this disease is alarming, so are the consequences—HF is a leading cause of hospitalization, morbidity, and mortality in the US [2–4]. HF is also a known risk factor for neurological disorders including Alzheimer’s disease, stroke, and vascular dementia [5–7]. However, it is now known that cognitive deficits begin to manifest long before patients are diagnosed with these more serious conditions. For example, recent studies have suggested that up to 75% of persons with HF exhibit deficits on testing, including reduced performance on tests of memory, attention, executive function, and language [8– 11]. A growing number of contributors to cognitive impair- ment in persons with HF have been identified, including structural brain changes, reduced cerebral blood flow, and autonomic nervous system disruption [12–16]. Although not previously examined, it appears likely that sleep apnea is another important contributor. Sleep apnea is common in persons with HF and has an independent adverse impact on cognitive function [17–21]. Recent work has shown that persons with sleep apnea score poorly on measures of attention [20–23], memory retrieval [24, 25], and executive