Objective: This study was an examination of 126 major depressive disorder (MDD) outpatients' morning to evening diurnal cortisol patterns to determine their association with family histories of mental illness, self-perceived depressive and anxiety distress, self-perceived health-related conditions, and healthy behaviors.
Methods: 126 MDD outpatients and 106 healthy subjects were recruited. Self-reports of symptom distress, health-related conditions, and healthy behaviors and objective measures of salivary cortisol upon awakening, 45min after awakening, and at 1200, 1700, and 2100h were collected at subjects' homes. The individual growth curve model was used to manage data and to analyze repeated observations of self-report data associated with diurnal cortisol patterns.
Results: For MDD outpatients, flatter diurnal cortisol patterns were more likely found in subjects with family histories of mental illness than in those without. Patient-reported shorter total sleep hours, more severe levels of depression and higher suffering levels were positively associated with flatter diurnal cortisol patterns. Less than 5 sleep hours was more likely associated with flatter diurnal cortisol patterns than above 7 sleep hours. Severe levels of depression were more likely related to flatter diurnal cortisol patterns than moderate and mild levels of depression. Higher anxiety levels, better sleep quality and higher levels of physical activity reported by patients were positively associated with steeper diurnal cortisol patterns. Unlike the MDD outpatients, the only trait associated with diurnal cortisol patterns in healthy subjects was total sleep hours.
Conclusions: These results suggested that self-perceived good sleep quality, total hours slept of 7 or greater, and self-perceived higher levels of physical activity in the home environment could be positively related to positive stress endocrine outcomes seen as steep diurnal cortisol patterns in outpatients with major depressive disorder.
Crown Copyright 2009. Published by Elsevier Ltd. All rights reserved.