Prevalence of obstructive sleep apnea in a patient population undergoing cardiac rehabilitation

: The primary objective of this study was to determine the prevalence of undiagnosed or untreated obstructive sleep apnea (OSA) in patients undergoing cardiac rehabilitation.

: A total of 132 consecutive patients were screened by Berlin Questionnaire to determine the presence or absence of OSA.

: Fourteen patients did not consent to participate. Of the remaining 118 patients, 20 (17%) were found to have a preexisting formal diagnosis of OSA. Of the remaining 98 patients (69 males and 29 females), 43 (44%) were found to have a high probability of OSA as predicted by the Berlin Questionnaire. There was no significant difference in the prevalence (P < .05) between males (29/69, 42%) and females (14/29, 48%) who were predicted to have OSA. Similarly, no significant differences were observed in the ages or body mass index between OSA and non-OSA patients. A significantly greater frequency (P < .05) of coronary artery disease was observed in the OSA group than in the non-OSA group.

: Overall, the rate of preexisting and predicted OSA (53%) suggests a high prevalence of OSA in patients with cardiovascular diseases in a cardiac rehabilitation setting. Moreover, the high rate of undiagnosed OSA, as suggested by the Berlin Questionnaire, further adds to the growing literature that a large number of patients with significant cardiovascular disease carry the burden of sleep disordered breathing.