Author Affiliations: Center for Cognitive Neuroscience (Dr Canessa), Università Vita-Salute San Raffaele (Dr Ferini-Strambi), Milan, Italy; and Division of Neuroscience (Drs Canessa and Ferini-Strambi) and Sleep Disorders Center (Dr Ferini-Strambi), San Raffaele Scientific Institute, Milan, Italy.
Sleep-disordered breathing has been associated with declines in memory, attention, and executive functions in both middle-aged adults and children, with intermittent hypoxemia and fragmented sleep patterns being the factors most frequently associated with decline.1 In elderly patients, some studies have found a relationship between cognitive impairment and sleep-disordered breathing,2,3 while others have not.4,5 However, conflicting results may be explained by methodological differences across these studies that assessed longitudinal data in elderly individuals,2 cross-sectional data from young and elderly individuals3 or only elderly individuals,5 or direct comparisons between younger and older patients.4 Most importantly, cross-sectional studies do not allow conclusions to be drawn regarding causality. Because sleep-disordered breathing is common among older adults and effective treatments for sleep-disordered breathing exist, establishing the possible prospective association between sleep-disordered breathing and cognitive functioning in elderly individuals is important at both theoretical and practical levels. The article by Yaffe et al6 in this issue of JAMA helps to clarify this association.
Canessa N, Ferini-Strambi L. Sleep-Disordered Breathing and Cognitive Decline in Older Adults. JAMA. 2011;306(6):654-655. doi:10.1001/jama.2011.1124