0710 The Association of Late-Life Depression, Cognitive Functioning, and Sleep Disorder in Aging

Abstract

Introduction: Late-life depression is common in aging and has strong association with cognitive impairment and neurological diseases, including Alzheimer’s Disease (AD). In this ongoing study, we hypothesized that participants with depression or depressive symptoms would exhibit sleep disorder and fragmentation when compared to aged-matched participants without depression. Methods: Independently living older adults, age 65-85 (M=72.76, SD=6.56), were recruited from a geriatric psychiatry clinic and the community. Participants who endorsed depression in interview were considered positive. Sleep was examined in the home with standard wrist actigraphy (Mini Actiwatch, Cambridge Neurotechnology) for 7 nights. Self-report sleep questionnaires (e.g. Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), Stanford Sleepiness Scale (SSS)) were used to identify subjective sleep quality, daytime sleepiness, and sleep efficiency. On the second night, overnight memory consolidation (ONMC) was tested before sleep and after wake with a brief procedural memory task. At one-month follow-up, neurocognitive assessment battery was administered. Results: 44.44% of 18 participants in this pilot study were positive for mild cognitive impairment (MCI), which was used as a covariate in ANCOVA analyses. Results from actigraphy reveal that self-reported depression was associated with longer sleep latency (p=0.004) and poorer sleep efficiency (p<0.001). PSQI scores reveal that depression status predicted longer sleep latency (p=0.043) and a trend toward lower sleep efficiency (p=0.055). No significant associations were found between depression and subjective sleepiness as measured by the SSS and ESS. No significant associations were found between depression status and neurocognitive measures, including overnight memory consolidation and 30 day, follow-up neurocognitive assessment. Conclusion: In this ongoing study, we found that sleep disturbance was more common in aging participants with self-report of depression, independent of MCI status. Both actigraphy and self-report on the PSQI confirm that sleep latency and sleep efficiency were different in depressed compared to non-depressed participants, with more insomnia in the depressed cohort. Contrary to expectations, impaired memory and cognition were not associated with depression self-report. In this cohort of older adults, depression affected sleep quality independent of cognitive performance and MCI status. Support (If Any): None