Pilot application of an inflammation and physiological dysregulation index based on noninvasive salivary biomarkers
Background and objective: Noninvasive salivary biomarkers can be used to assess the cumulative subclinical health impacts of social and environmental stressors. We evaluated seven salivary biomarkers of neuroendocrine and immune functions and a group index of physiological dysregulation based on these biomarkers in a pilot survey. Results: Participants recruited at subsidized public housing projects in Denver, Colorado, completed a sociodemographic, behavioral, and health questionnaire and used passive drool samplers to collect five saliva samples over the course of 1 day. Samples were tested for the neuroendocrine biomarkers alpha-amylase, cortisol, and dehydroepiandrosterone (DHEA) as well as immune system/inflammation biomarkers C-reactive protein (CRP), interleukin (IL)-1β, IL-6 and total immunoglobulin A (IgA). A composite Inflammation and Physiological Dysregulation Index (IPDI) was calculated as a count of potentially unhealthy values of dichotomized biomarkers. In 20 individuals who completed the survey (average age 46 years, 75% females), allergy to house dust was significantly associated with increased IPDI (adjusted for age) and significantly increased odds of potentially unhealthy values of total IgA, IL-1β, and CRP. Age, obesity, diabetes, allergy to pollen, recent loss of employment, and depression, anxiety, and stress scores from the standard DASS-21 questionnaire were positively but not significantly (0.05 < p < 0.2) associated with IPDI. This project demonstrated an application of a composite index based on noninvasive salivary biomarkers to assess subclinical health impacts of chronic social stressors.