0921 Sleep Efficiency Mediates the Association between Psychological Distress and Inflammation

Research demonstrates well-established associations between inflammatory mechanisms, sleep, mood disturbances, and a wide spectrum of medical conditions. Specifically, insufficient and disturbed sleep is associated with increased systemic inflammation as well as psychological dysregulation and morbidity. However, limited research exists exploring the relative mediational role that sleep disturbance may play in the relationship between psychological distress and inflammatory risk. The purpose of this study is to examine if objective sleep quality (i.e., sleep efficiency) mediates the association between psychological distress and low-grade inflammation. We utilized a sample of adults from the Midlife in the United States (MIDUS) II study (2004-2009) who completed the biomarker blood assays and actigraphy project (N = 441). Seven-day average sleep efficiency, estimated from wrist actigraphy, was used as the objective sleep quality measure. Low grade inflammation score was indexed as a composite of five standardized inflammatory markers (Interleukin 6, C-reactive protein, fibrinogen, intercellular adhesion molecule-1, and E-selectin). Psychological distress was assessed using the Center for Epidemiological Studies for Depression Inventory (CES-D), Mood and Symptom Questionnaire (MASQ), and the Perceived Stress Scale-10 item version (PSS). A mediation analysis was run using the PROCESS macro (Hayes, 2017; model 4; 5000 bootstrap samples) with body mass index, age, and sex entered as covariates. Significant mediation is observed when the 95% confidence interval excludes zero. Results indicated that sleep efficiency mediated the associations between all measures of psychological distress [depression (95% CI = .0035, .0213), anxiety (95% CI = .0033, .0294), perceived stress (95% CI = .0052, .0291] and low-grade inflammation. Results indicate objective sleep disturbance among individuals experiencing elevated levels of stress, depression, and anxiety may increase their risk for inflammation. Findings suggest that enhancing sleep quality may be an effective prevention strategy to reduce low-grade inflammation when individuals are experiencing psychological distress. Additional implications and future directions will be discussed. N/A