title: Negative emotionality, depressive symptoms and cortisol diurnal rhythms: analysis of a community sample of middle-aged males.
abstract: Prior research suggests that individuals with particular personality traits, like negative emotionality, are at greater risk for adverse health outcomes. Despite bivariate associations between negative emotionality, depressive symptoms and the hypothalamic pituitary adrenal axis (HPA axis), few studies have sought to understand the biological pathways through which negative emotionality, depressive symptomatology and cortisol-one of the primary hormonal products of the HPA axis--are associated. The present study explored whether negative emotionality influenced cortisol dysregulation through current depressive symptomatology and whether negative emotionality served as a moderator of the relationship between depressive symptoms and cortisol. In the community-based Vietnam Era Twin Study of Aging, 783 male twins completed two days of cortisol saliva sampling in their natural environments. Three measures of cortisol were analyzed: waking levels, the cortisol awakening response, and the peak to bed slope. Depressive symptoms significantly mediated the associations between negative emotionality and the peak to bed slope. A 2-way interaction between depressive symptoms and negative emotionality was significant for the peak to bed slope and for waking levels of cortisol. Exploration of the interactions illustrated that depressive symptoms only affected cortisol slopes at average or high levels of negative emotionality and only affected waking levels at low levels of negative emotionality. Negative emotionality and depressive symptoms were not related to the cortisol awakening response. This is the first study to find indirect associations between negative emotionality and peak to bed cortisol slopes through depressive symptoms. These findings illustrate the complex interplay between personality characteristics, depressive symptoms and different indices of the cortisol diurnal rhythm.
authors.affiliation: Department of Psychology, Arizona State University, Tempe, AZ 85287-1104, USA. Leah.Doane@asu.edu
authors.forename: Leah D
authors.initials: LD
authors.lastname: Doane
authors.forename: Carol E
authors.initials: CE
authors.lastname: Franz
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Prom-Wormley
authors.forename: Lindon J
authors.initials: LJ
authors.lastname: Eaves
authors.forename: Sally P
authors.initials: SP
authors.lastname: Mendoza
authors.forename: Dirk H
authors.initials: DH
authors.lastname: Hellhammer
authors.forename: Sonia
authors.initials: S
authors.lastname: Lupien
authors.forename: Hong
authors.initials: H
authors.lastname: Xian
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Lyons
authors.forename: William
authors.initials: W
authors.lastname: Kremen
authors.forename: Kristen C
authors.initials: KC
authors.lastname: Jacobson
mesh_terms: D002940:Circadian Rhythm / Q000502:physiology*; D003863:Depression / Q000175:diagnosis* / Q000378:metabolism; D004200:Diseases in Twins / Q000378:metabolism / Q000523:psychology; D004644:Emotions / Q000502:physiology*; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism*; D007030:Hypothalamo-Hypophyseal System / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D010913:Pituitary-Adrenal System / Q000378:metabolism; D011569:Psychiatric Status Rating Scales; D012463:Saliva / Q000378:metabolism; D013315:Stress, Psychological / Q000378:metabolism; D011795:Surveys and Questionnaires; D014427:Twins
chemical_list: D006854:Hydrocortisone