@article {1018, title = {Sleep-disordered breathing and cardiovascular disease: an outcome-based definition of hypopneas.}, journal = {Am J Respir Crit Care Med}, volume = {177}, year = {2008}, month = {2008 May 15}, pages = {1150-5}, abstract = {

RATIONALE: Epidemiologic studies on the consequences of sleep-disordered breathing invariably use the apnea-hypopnea index as the primary measure of disease severity. Although hypopneas constitute a majority of disordered breathing events, significant controversy remains about the best criteria used to define these events.

OBJECTIVES: The current investigation sought to assess the most appropriate definition for hypopneas that would be best correlated with cardiovascular disease.

METHODS: A community sample of middle-aged and older adults was recruited as part of the Sleep Heart Health Study. Full-montage polysomnography was conducted and hypopneas were defined using different thresholds of oxyhemoglobin desaturation with and without arousals. Prevalent cardiovascular disease was assessed based on self-report. Logistic regression analysis was used to characterize the independent association between the hypopnea index and prevalent cardiovascular disease.

MEASUREMENTS AND MAIN RESULTS: Using a sample of 6,106 adults with complete data on cardiovascular disease status and polysomnography, the current study found that hypopneas associated with an oxyhemoglobin desaturation of 4\% or more were associated with prevalent cardiovascular disease independent of confounding covariates. The adjusted prevalent odds ratios for quartiles of the hypopnea index using a 4\% desaturation criterion were as follows: 1.00 (<1.10 events/h), 1.10 (1.01-3.20 events/h), 1.33 (3.21-7.69 events/h), and 1.41 (>7.69 events/h). Hypopnea measures based on less than 4\% oxyhemoglobin desaturation or presence of arousals showed no association with cardiovascular disease.

CONCLUSIONS: Hypopneas comprise a significant component of sleep-disordered breathing in the general community. By varying the criteria for defining hypopneas, this study demonstrates that hypopneas with a desaturation of at least 4\% are independently associated with cardiovascular disease. In contrast, no association was observed between cardiovascular disease and hypopneas associated with milder desaturations or arousals.

}, keywords = {Aged, Apnea, Cardiovascular Diseases, Cohort Studies, Female, Humans, Male, Middle Aged, Odds Ratio, Oxyhemoglobins, Polysomnography, Sleep Apnea Syndromes, Terminology as Topic}, issn = {1535-4970}, doi = {10.1164/rccm.200712-1884OC}, author = {Punjabi, Naresh M and Newman, Anne B and Young, Terry B and Resnick, Helaine E and Sanders, Mark H} }