LAUSR

Prior research assessing self-reported or nocturnal sleep suggested that specific sleep traits (sleep restriction in the laboratory; poor sleep quality, sleep disorders) are associated with both pro and anti-inflammatory cytokine and C-Reactive Protein (CRP) levels. To extend prior research, we investigated associations between multiple dimensions of objectively assessed sleep health with both circulating and stimulated inflammatory markers in a diverse sample of older adults. Participants in the Einstein Aging Study (EAS) were included (N=218, Mage=77.5 years, 6% female; 46% White, 38% Black, 14% Hispanic/other). A confirmatory factor analysis using wrist actigraphy sleep variables over 16 days yielded 6-component multi-dimensional sleep health facets: Regularity, Alertness/Sleepiness (daytime), Timing, Efficiency, Duration, and Rhythmicity. Inflammatory markers collected in the morning included CRP and both circulating markers reflecting current systemic inflammation, and lipopolysaccharide (LPS)-stimulated levels of (IL-1β, IL-4, IL-6, IL-8, IL-10, TNF𝛼), which reflect responses to an inflammatory challenge, an index of immune reactivity. Associations between each inflammatory marker and each sleep health facet were examined using linear regression, controlling for BMI, gender, age, education, ethnicity/race, number of health conditions, nocturnal hypoxemia, Oxygen Desaturation Index (ODI)≥15. Participants with more daytime sleepiness (i.e., higher number and longer duration of naps and lower activity level) had higher circulating IL-6 and CRP levels. Lower sleep efficiency was associated with lower levels of the anti-inflammatory circulating cytokine IL-4 and higher levels of stimulated IL-8 and TNF𝛼. Longer sleep duration was associated with higher levels of circulating IL-1β and CRP. Less rhythmicity across days was associated with higher levels of circulating IL-6. Nocturnal hypoxemia was associated with higher levels of CRP and stimulated IL-4, IL-8, and TNFα. We found no association between sleep timing and regularity and any inflammatory marker. We observed that various sleep health facets are related to markers of inflammation and immune reactivity in older adults. This research also demonstrates the value of using 24-hour, device-based estimates of different sleep health facets relevant for immune function. Associations between 24-h sleep and inflammation are particularly important for older adults, who evidence more daytime sleepiness and less rhythmic sleep/active patterns in daily life. R01AG062622, P01AG003949, RF1AG056331-04