Chronic stress and illness in children: The role of allostatic load

Objective: Recent studies of stress have highlighted the contributions of chronic psychological and environmental stressors to health and well-being. Children may be especially vulnerable to the negative effects of chronic stressors. Allostasis, the body's ability to adapt and adjust to environmental demands, has been proposed as an explanatory mechanism for the stress-health link, yet empirical evidence is minimal. This study tested the proposition that allostasis may be an underlying physiological mechanism linking chronic stress to poor health outcomes in school-aged children. Specifically, we examined whether allostasis would mediate or moderate the link between chronic stress and health. Method: To test the hypothesis that allostasis contributes to the relation between chronic stress and poor health, we examined household density as a chronic environmental stressor, cardiovascular reactivity (CVR) as a marker of allostatic load, and number of school absences due to illness as the health outcome in a sample of 81 boys. Results: Structural equation modeling indicated that the mediating model fit the data well, accounting for 17% of the variance in days ill. Conclusions: Results provide the first evidence that CVR may mediate the relation between household density and medical illness in children. More generally, these findings support the role of allostasis as an underlying mechanism in the link between chronic stress and health.