Stress Biomarkers as an Objective Window on Experience

Stress Biomarkers as an Objective Window on Experience.  Daniel E. Brown, University of Hawaii at Hilo

Many studies of psychosocial stress in humans rely upon self-reports as the measure of both the presence and intensity of stress.  The self-reports take many forms, from carefully constructed psychological instruments to diary reports, and from long term life events to short term hassles scales. Ethnic group differences have been found in these scores, but it is unclear whether this implies a “real” difference in stress levels, or a culturally-based reporting bias.  Biological responses to stress, based on activation of either the sympathetic-adrenal medullary or pituitary adrenal-cortical systems, long predate the origins of our species and may serve as biomarkers of stress independent of reporting bias.  These measures raise their own concerns, such as the time frame of stress (sometimes dichotomized as “state” or “trait”), the degree of invasiveness, and their correlation with the self-report measures.  Examples from studies among Hawaii’s multiethnic population will illustrate these ideas.  For example, stress measured through a health symptom survey showed significant differences between two Filipino American (FA) ethnic groups living in the same community on Oahu, but no significant differences in 24-hour norepinephrine or epinephrine levels were found.  When FA, largely immigrant, nurses were compared with European American (EA) co-workers, FAs were significantly more likely to report negative moods - primarily anxiety - during household chores, but unlike EAs, showed no significant elevation in ambulatory blood pressure during those times.  Other examples will be presented, and the value of use of both self-report and biomarker measures of stress will be discussed.