Lifetime stress exposure and health: A review of contemporary assessment methods and biological mechanisms

Life stress is a central construct in health research because it is associated with increased risk for a variety of serious mental and physical health problems, including anxiety disorders, depression, cardiovascular disease, autoimmune disorders, Alzheimer's disease, certain cancers, and other diseases of aging. In this review, we examine how lifetime stress exposure contributes to elevated disease risk and explore ongoing measurement and scientific issues related to this topic. To accomplish these goals, we first review existing instruments that have been developed for assessing perceived stress, self-reported life events, interviewer-assessed life stressors, and lifetime stress exposure. Next, we describe laboratory-based tasks that have been used for characterizing individual differences in psychological and biological stress reactivity. These methods have yielded an enormous amount of data showing how life stress influences the activity of the hypothalamic-pituitary-adrenal axis, hypothalamic-pituitary-gonadal axis, sympathetic-adrenal-medullary axis, and immune system, and how such processes can in turn cause allostatic load and biological embedding of the stress effect at the level of the human brain and genome. At the same time, many critical measurement and scientific issues remain unresolved, and we discuss these topics last while describing some pressing issues and opportunities for future research on stress and health.