Objectives: To measure the ability of the Observation-based Nocturnal Sleep Inventory (ONSI) to detect the presence or absence of sleep apnea syndrome (SAS) in older adults.
Design: Cross-sectional blinded study.
Setting: University hospital-based geriatric sleep center.
Participants: All participants aged 70 and older were referred by physicians for suspicion of SAS.
Measurements: ONSI performed by nurses; overnight polysomnography. SAS was defined as an apnea-hypopnea index of 15 events or more per hour of sleep.
Results: A total of 121 consecutive patients were evaluated for study participation. Six were excluded because of technical difficulties with polysomnography or too-frequent awakenings related to medical conditions. One hundred eleven patients completed the validation process. Polysomnography identified 68 patients as having SAS and 43 patients as not having SAS. The nurse-administered ONSI demonstrated good levels of sensitivity (90%), specificity (81%), positive predictive value (88%), and negative predictive value (83%) in screening older adults for SAS.
Conclusion: The ONSI is the first valid SAS screening tool proposed for older persons in hospitals and nursing homes. This study demonstrates that the ONSI provides accurate information; is a simple, easy-to-use bed-side tool; and is highly sensitive and specific in screening SAS when compared with overnight polysomnography results.