Sleep Inconsistency and Markers of Inflammation

Abstract

Poor sleep is associated with higher levels of inflammatory biomarkers. Conventionally, higher average time awake, lower average time asleep, and lower sleep efficiency define poor sleep. Recent research suggests that, in addition to average sleep, sleep inconsistency is an important indicator of sleep dysfunction. The current study sought to extend our knowledge of the relationship between sleep and inflammation through an examination of sleep inconsistency and inflammatory biomarkers. Methods: Secondary analyses of the Survey of Midlife in the United States (MIDUS) sleep study were conducted. Five hundred thirty-three individuals completed nightly sleep diaries, actigraphy, and underwent a blood draw for the inflammatory biomarkers C-reactive protein, interleukin-6, and fibrinogen. Sleep inconsistency was derived from 7 consecutive nights of assessment and was operationalized as nightly fluctuations in the following variables: terminal wakefulness, number of awakenings, time in bed, sleep onset latency, and wake after sleep onset. Structural equation modeling was used to examine the influence of a latent average sleep and a latent sleep inconsistency variable on a latent inflammation variable. Models were subsequently adjusted for age, sex, BMI, health, and medication. Stratified models by sex were also analyzed. Results: The average sleep model would not converge. The sleep inconsistency model fit the data well. A significant positive association between the latent factors sleep inconsistency and inflammation was observed (β = 10.18, SE = 4.40, p = 0.021), suggesting inconsistent sleep is associated with higher levels of inflammatory biomarkers. When stratified by sex, the association between the latent sleep inconsistency factor and inflammation was significant for women (β = 1.93, SE = 0.82, p = 0.018), but not men (β = 0.20, SE = 0.35, p = 0.566). The association between sleep inconsistency and inflammation weakened following multivariate adjustment (β = 6.23, SE = 3.71, p = 0.093). Conclusions: Inconsistent sleep may be an associated feature of inflammatory dysfunction, especially in women. Future studies should build upon this preliminary work and examine these associations longitudinally and through treatment trials.

Association between Preexisting Sleep Disorders and Oncologic Outcome in Patients with Oral Cavity Squamous Cell Carcinoma: A Nationwide Propensity Score—Matched Population-Based Cohort Study

“…Although immune system dysregulation may explain the association between sleep disorders and mortality, whether similar biological mechanisms explain the association of preexisting sleep disorders with all-cause death, LRR, and DM remain unclear. OSCC patients with sleep disorders have shorter survival, possibly because sleep disorders are associated with systemic inflammation [ 36 , 37 ], which is in turn associated with the pathways similar to those of OSCC progression [ 38 , 39 ]. Systemic inflammation markers, such as C-reactive protein, interleukin 6, and fibrinogen, have been linked to poor sleep [ 37 ].…”

“…OSCC patients with sleep disorders have shorter survival, possibly because sleep disorders are associated with systemic inflammation [ 36 , 37 ], which is in turn associated with the pathways similar to those of OSCC progression [ 38 , 39 ]. Systemic inflammation markers, such as C-reactive protein, interleukin 6, and fibrinogen, have been linked to poor sleep [ 37 ]. Systemic inflammation is an independent predictor for clinical outcomes in patients with OSCC [ 40 ].…”

Loneliness and multiple health domains: associations among emerging adults

“…For example, higher loneliness is associated with higher inflammatory markers (Cho et al, 2015 ; Smith et al, 2020 ), and inflammation can trigger changes in neurotransmitters that affect sleep patterns and behaviors (social withdrawal) (Irwin, 2019 ). A study of middle-aged adults found that inconsistent sleep is associated with higher levels of inflammatory markers (Dzierzewski et al, 2020 ). Thus, inflammation may lead to or be a consequence of poor sleep, and loneliness may exacerbate this process.…”

A structural equation modeling approach for modeling variability as a latent variable.

“…Meanwhile, the biomarker specimen assays yielded various indicators reflecting different aspects of internal metabolic functioning, among which there are interleukin-6 (IL6), c-reactive protein (CRP), and fibrinogen (FGN), that are commonly treated as inflammation markers. Thus, this example addresses the relation between sleep inconsistency and physical health, an area in which scientists have shown increasing interest (e.g., Dzierzewski et al, 2020).…”