Inflammation, Stress & Social Behavior: Using Ecological Assessments & Model Systems to Enhance Relevance to Health Outcomes

The current study has been designed to identify behavioral and physiological mechanisms through which positive social connectivity (PCS) and negative social processes (NSP) interact with psychosocial stress to promote resilience in the context of illness. The investigators model inflammation (a central element of all disease states) through the use of treatment with interferon (IFN)-alpha, which provides a standardized regimen of chronic cytokine exposure known to produce profound behavioral disturbances, including depression, fatigue and sickness, in a high percentage of individuals. To objectively assess social processes, the current project will employ the Electronically Activated Recorder (EAR), which periodically and unobtrusively records snippets of ambient sounds in people's momentary environments. To objectively assess behavioral and physiological responses to psychosocial stress the current project will employ the Trier Social Stress Test (TSST), a standardized laboratory stressor known to reliably activate behavioral, neuroendocrine and inflammatory responses. These novel methodologies and model systems will be employed to test the hypotheses that (a) pre-existing affiliative and prosocial behavior will promote resilience in the context of chronic inflammation and that (b) -conversely-chronic inflammation will reduce affiliative and prosocial behavior via effects on stress reactivity, neuroendocrine function and sleep. Finally, it will explore (c) the potential mediating role of stress physiology. To test these hypotheses, 110 subjects with chronic hepatitis C virus infection will be randomized to receive treatment with pegylated IFN-alpha plus ribavirin or to postpone treatment for 6 weeks: 55 subjects at University of Arizona and 55 subjects at Emory University. Prior to randomization and 6 weeks later all subjects will be evaluated with the EAR and sleep actigraphy in their home environments and will undergo TSST and 14 hour diurnal neuroendocrine and i