Abstract C078: Relations between sleep and inflammation in African American and White young adults: Testing mediating and moderating mechanisms
Authors: Doan Stacey N. , Fuller-Rowell Thomas E. , Schmolze Daniel B. , Seewaldt Victoria 
Published: August 2020

Abstract
In this study, we examined the relations between sleep and inflammation in a sample of African American (AA) and White young adults. Immune activity has a broad impact on tumor initiation, growth and progression, which are thought to be mediated by proinflammatory cytokines, among which the protumorogenic function of interleukin 6 (Il-6) is well established (Grivennikov & Karin, 2011). A range of health behaviors is associated with increased Il-6 levels (Duivis et al., 2011). Of particular interest is the association between sleep and IL-6 levels in AAs and Whites, given recent work suggesting that racial differences in sleep may contribute to disparities in health (Curtis et al., 2017). Research examining ethnic health disparities has suggested the possibility that stigmatized minority groups may be more susceptible to the consequences of biologic dysregulation and accelerated physiologic aging due to differential exposure to adversity (Hogue, 2002). A few studies have investigated this Weathering Hypothesis by studying the associations among inflammatory biomarkers and a range of psychological and health factors (Geronimus, Hicken, Keen & Bound, 2006), with some studies demonstrating relations between inflammatory biomarkers and outcomes in AAs, but not Whites (Blair, Porter, Lebleicioglu, & Christian, 2015; Slopen, Lewis, Gruenewalkd, Mujahid, Ryff, Albert & Williams, 2010; Christian, Glaser, Porter and Iams, 2013). Another alternative model is that disparities in specific health behaviors may lead to potential group differences in IL-6 levels. The analytic sample for this study comprised 133 college students (mean age 18.8 years, SD 0.9; 41% AA, 57% female). IL-6 was assessed by enzyme-linked immunosorbent assay with a detection range of 0.16 to 10.0 pg/ml. Participants reported on sleep using the Pittsburgh Sleep Inventory. We tested both mediation and moderation models. Results suggest significant group differences in sleep, but not in IL-6 levels. AAs reported significantly worse sleep (M = 4.3, SD = 3.6) as compared to Whites (M = 3.6, SD = 1.88). Additionally, results were consistent with our hypothesis that poor sleep would be associated with higher levels of IL-6 for AAs, but not for Whites. Specifically, using bootstrapping to test for moderation, we found that the interaction between sleep and race was significant (B = .08, SE = .02, p = .001, CI [1.3, 3.8]). In particular, for AAs, elevated IL-6 was associated with more sleep problems (B = .05, SE = .02, p = .003, CI [.02, .09]). The substantive finding held even after controlling for a range of demographic variables and health behaviors. Our results provide support for the idea that AAs are more susceptible to the consequences of behavioral dysregulation.
Citation Format: Stacey N. Doan, Thomas E. Fuller-Rowell, Daniel B. Schmolze, Victoria Seewaldt. Relations between sleep and inflammation in African American and White young adults: Testing mediating and moderating mechanisms [abstract]. In: Proceedings of the Eleventh AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2018 Nov 2-5; New Orleans, LA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl):Abstract nr C078.