Sleep-Disordered Breathing: A Heart-Changing Experience?

Abstract

Increasingly, sleep-disordered breathing (SDB) is recognized as an important risk factor for coronary atherosclerosis and heart disease. Several large epidemiologic studies 1 Mooe T Rabben T Wiklund U et al. Sleep-disordered breathing in women: occurrence and association with coronary artery disease. Am J Med. 1996; 101: 251-256 Abstract Full Text PDF PubMed Scopus (169) Google Scholar ,2 Shahar E Whitney CW Redline S et al. Sleep-disordered breathing and cardiovascular disease: cross-sectional results of the Sleep Heart Health Study. Am J Respir Crit Care Med. 2001; 163: 19-25 Crossref PubMed Google Scholar have demonstrated that SDB increases the risk of heart disease by approximately twofold to fourfold, independent of other risk factors. While the exact mechanisms responsible for this association are largely unknown, there is credible evidence to indicate SDB can increase systemic BP 3 Nieto FJ Young TB Lind BK et al. Association of sleep-disordered breathing, sleep apnea, and hypertension in a large community-based study. JAMA. 2000; 283: 1829-1836 Crossref PubMed Scopus (2735) Google Scholar ,4 Peppard PE Young T Palta M et al. Prospective study of the association between sleep-disordered breathing and hypertension. N Engl J Med. 2000; 342: 1378-1384 Crossref PubMed Scopus (3965) Google Scholar and sympathetic drive. 5 Phillips BG Kato M Narkiewicz K et al. Increases in leptin levels, sympathetic drive, and weight gain in obstructive sleep apnea. Am J Physiol Heart Circ Physiol. 2000; 279: H234-H237 PubMed Google Scholar It may also elevate circulating levels of fibrinogen 6 Wessendorf TE Thilmann AF Wang YM et al. Fibrinogen levels and obstructive sleep apnea in ischemic stroke. Am J Respir Crit Care Med. 2000; 162: 2039-2042 Crossref PubMed Scopus (227) Google Scholar and C-reactive protein, 7 Shamsuzzaman AS Winnicki M Lanfranchi P et al. Elevated C-reactive protein in patients with obstructive sleep apnea. Circulation. 2002; 105: 2462-2464 Crossref PubMed Scopus (803) Google Scholar triggering a cascade of events that eventually leads to thrombus formation in the coronary vasculature. Treatment of SDB, usually with continuous positive airway pressure, leads to significant improvements in these physiologic parameters. 8 Narkiewicz K Kato M Phillips BG et al. Nocturnal continuous positive airway pressure decreases daytime sympathetic traffic in obstructive sleep apnea. Circulation. 1999; 100: 2332-2335 Crossref PubMed Scopus (423) Google Scholar