Nocturnal autonomic nervous system activity and morning proinflammatory cytokines in young adult African Americans.

Compromised sleep and increased sympathetic nervous system (SNS) activity are implicated in the pathogenesis of, and disparities in, cardiovascular disease. Parasympathetic dominance during sleep may be important for cardiovascular health. Sleep and autonomic balance influence immune activity, which impacts atherogenesis. We evaluated relationships between autonomic balance during sleep and morning levels of the immune activating cytokines, C-reactive protein (CRP) and interleukin (IL)-6. Ninety-four (59 female) young adult African Americans without medical conditions and substance use disorders spent 2 consecutive nights in a clinical research unit for sleep recordings and blood drawing on awakening. Cardiac tracings from the second sleep recording were analysed for heart rate variability (HRV). Body mass index was the only non-HRV measure correlated with cytokine levels. Indicators of SNS activity for the presleep, and first non-rapid eye movement (REM) and REM sleep periods were correlated independently with morning IL-6 levels. Altered autonomic balance during sleep may be a modifiable factor that influences immune activation.