Peripheral biomarker composite associated with smaller hippocampal volume

Abstract

Animal and human studies demonstrate an association between smaller hippocampal volume and stress. A composite index of peripheral biomarkers used to objectively quantify human psychosocial stress has demonstrated utility, but has not yet been linked to hippocampal volume in putative 'high stress' groups. Structural magnetic resonance imaging exams and a composite of biomarkers representing cardiovascular, atherosclerosis, hypothylamic-pituitary-adrenal axis, glucose metabolism, and sympathetic nervous system activity were assessed in 30 healthy women with histories of stress precipitated by their child's diagnosis of a life-threatening illness. Hippocampal volume was significantly predicted by age, time since stressor onset, and the composite. An objective biomarker index may improve temporal tracking of brain changes in relation to stress-related psychological symptoms, with implications for basic and clinical research.