0116 Associations Between Subjective Sleep Variability and Inflammatory Cytokines from Early Pregnancy to One Year Postpartum

Abstract Introduction Cytokine levels fluctuate throughout gestation in healthy pregnancy, but excessive inflammation is associated with sleep disruption and poor maternal outcomes. Sleep intra-individual variability (IIV), a correlate of insomnia, is not captured by traditional assessments of average sleep and may uniquely contribute to inflammation across the perinatal period. We investigated whether subjective sleep IIV was associated with inflammatory cytokine levels across the perinatal period. Methods A subsample of participants in the Healthy Babies Before Birth study (N=142 women) completed the Pittsburgh Sleep Quality Index and blood samples at 8-16 and 30-36 weeks pregnant and 6 and 12 months postpartum. We defined high vs. low IIV in 4 variables: 1. PSQI total (global sleep quality), 2. sleep duration, 3. midsleep timing, and 4. sleep efficiency. We calculated within-person standard deviation for each variable and designated the top and bottom 30% as high vs. low IIV, respectively. Cytokines were assayed using a custom V-PLEX human immunoassay plate (Meso Scale Discovery) and included IFN-γ, IL-6, IL-8, IL-10, and TNF-α. We tested ANOVAs for each sleep IIV variable on each cytokine across the 4 timepoints. Results are reported as estimated marginal means (EMM). All p-values were FDR-corrected. Results Women with high IIV in global sleep quality (EMM=1.51, SE=0.05) exhibited significantly lower IL-8 at 6 months postpartum compared to women with low IIV (EMM=1.71, SE=0.05, p< 0.05), but not at the other timepoints. Women with high IIV in midsleep timing (EMM=1.04, SE=0.03) exhibited significantly lower TNF-α at 12 months postpartum compared to women with low IIV (EMM=1.16, SE=0.03, p< 0.05), though not at other timepoints. Women with high IIV in sleep efficiency (EMM=0.36, SE=0.03) exhibited significantly higher IL-10 at 30-36 weeks pregnant compared to women with low IIV (EMM=0.25, SE=0.03, p< 0.05), but not at other timepoints. IL-6 and IFN-γ results were not statistically significant. Conclusion Greater variability in subjective sleep was related to inflammatory markers across pregnancy and postpartum. Circulating inflammatory cytokines during postpartum are not well studied, and their clinical relevance remains unclear. Further examination of the relationships between sleep and inflammation in pregnancy and postpartum is warranted. Support (if any) NIH R01HD073491; NIH K23MH137376; McDonnell Center for Systems Neuroscience