Résumé
OBJECTIVES: Obstructive sleep apnea (OSA) is classified as positional sleep apnea (POSA) and non-positional sleep apnea (NPOSA) according to apnea-hypopnea index (AHI) changed by sleep position. The aim of this study was to compare neurocognitive functions between two groups in the elderly Korean population. METHODS: Forty-four subjects in OSA patients with total AHI> or =5 participated as criteria for POSA (n=25) with 1) supine position AHI/non-supine position AHI> or =2 and 2) total AHI> or =5 or not (NPOSA, n=19). All participants completed clinical interview by physician and neurocognitive function assessments. Mann-Whitney U and chi-square test were performed for comparison of neurocognitive functions and sleep characteristics with polysomnography between two groups. RESULTS: No significant difference in demographic and clinical characteristics was observed between the two groups. However the NPOSA group showed more decline than the POSA group on the Boston naming test (p=0.034), digit span test (p=0.001), go-no-go test (p=0.042), and fist-edge-palm test (p=0.007). CONCLUSION: In this study NPOSA patients were found to have lower cognitive functions compared to POSA patients. A larger sample and long term follow-up study might be needed.