0272 Decreased Risk of 2-Year Incidence of Alzheimer’s Disease Among Older Adults Who Report Sleep Symptoms

Abstract

Introduction Those with dementia or Alzheimer’s Disease report an elevated amount of sleep difficulties compared to age-matched controls. Sleep-based interventions may be especially useful for this group, such as cognitive behavioral therapy for insomnia or pharmacological interventions. Therefore, it is important to expand the current understanding of the nature of sleep difficulties in those with Alzheimer’s Disease. Methods Data from the 2018 Health and Retirement Survey was collected from 17,146 older adults. Poisson regression analyses were used to explore the relationship between Alzheimer’s Disease as diagnosed by a doctor and sleep difficulties. Individuals who reported no Alzheimer’s Disease in the previous wave (N=16,751) were asked if they had since become diagnosed. N=101 individuals reported incident Alzheimer’s Disease in the 2-year gap between assessments. Sleep difficulties were assessed by asking participants if they had difficulties initiating or maintaining sleep, waking up too early, and how rested they felt upon awakening. All 4 of these symptoms were coded as “never,” “sometimes,” or “often.” Results Unexpectedly, there was a significant decreased risk of developing Alzheimer’s Disease among those who reported difficulties maintaining sleep (IRR=0.9962; 95%CI[0.9936,0.9988]; p=0.004), and early morning awakenings (IRR=0.9961; 95%CI[0.9938,0.9984]; p=0.001) “sometimes”. When the model was adjusted for sex, race, ethnicity, age, and depression, a similar finding of decreased risk for Alzheimer’s Disease for those who reported difficulties maintaining sleep (IRR=0.9953; 95%CI[0.9927,0.9980]; p<0.001), and early morning awakenings (IRR=0.9954; 95%CI[0.9930,0.9978]; p=0.001), “sometimes” were maintained. Conclusion Although previous studies have shown that poor sleep may lead to increased risk of Alzheimer’s and related dementias, the present study, which examined longitudinal data from a large, national sample of older adults, found that there was no association between frequent sleep disturbances and 2-year incidence of Alzheimer’s Disease, and a small association between more mild symptoms and decreased risk. It is possible that the 2-year observation window was insufficient to detect effects. Also, there is a risk of measurement error in collecting self-reported data on sleep and Alzheimer’s diagnoses. Support (If Any) The HRS (Health and Retirement Study) is sponsored by the National Institute on Aging (grant number NIA U01AG009740) and is conducted by the University of Michigan.

Sleep Disturbances and Dementia Risk in Older Adults: Findings From 10 Years of National U.S. Prospective Data

“…Despite the initial hypotheses, though, respondents with sleep-maintenance insomnia were less likely to develop dementia over the course of the decade than respondents who did not report insomnia. This negative association falls in an interesting spot in the literature: while some studies have found positive associations, 11,22 others have similarly found negative ones 23 or no association at all. 21,24 These mixed results deserve further research for their own clarity, but, if the negative association is correct, more investigation should be done on how these conditions can connect counterintuitively.…”

“…25 This extra productivity may be the mechanism by which those with sleep-maintenance insomnia reduce their own dementia risk over the years. 23 Lastly, sleep medication usage was significantly associated with dementia incidence in only the second of the Cox regression models. This finding was partially expected: many older adults take sleep medication due to their health conditions, 27 and controlling for health variables would have thus attenuated the association between sleep medication and dementia.…”