SLEEP-DISORDERED BREATHING IN HEALTHY, AGED PERSONS - 5TH AND FINAL YEAR FOLLOW-UP

The frequency of sleep-disordered breathing (SDB) events increases dra matically with age, although the clinical significance of this phenome non is uncertain. We report herein on data from the fifth follow-up ob servation of a cohort of healthy elderly which we selected, evaluated, and followed up in an effort to address this issue. Baseline observat ions on this group of 95 normal older persons medically screened for g ood health included standard nocturnal polysomnograms and daytime asse ssment of medical, sleep/wake, and psychological variables. At fifth-y ear follow-up, 42 subjects returned for assessment. Comparison of retu rning vs nonreturning subjects indicated no significant differences in baseline characteristics between these groups. Division of returning subjects into moderate (apnea-hypopnea index [AHI] greater than or equ al to 5) vs low (AHI<5) SDB at baseline resulted in 10 subjects in the moderate group and 32 subjects in the low group, The two groups were comparable with regard to sex, weight, and education, although the mod erate SDB group was significantly older (70.4 years) than the low SDB group (64.8 years). Follow-up medical, sleep/wake, and psychological d ata were contrasted for the two groups using a mixed design multivaria te analysis of valiance (repeated measures factor-time-6 observations; between-subjects factor SDB level, 2 groups). There were no statistic ally significant effects of SDB or interactions of SDB and time across this 5-year followup. These results confirm observations from the thi rd-year follow-up. We conclude that observation of a moderate level of SDB in an otherwise healthy older person is apparently not a signific ant risk across a 5-year follow-up period and therefore does not seem to warrant investigation beyond a thorough medical history and physica l examination to rule out other disorders.