Low Salivary Cortisol Levels and Externalizing Behavior Problems: A Latent State Trait Model in Normally Developing Youth
Open Access
Author:
Shirtcliff, Elizabeth Anne
Graduate Program:
Biobehavioral Health
Degree:
Doctor of Philosophy
Document Type:
Dissertation
Date of Defense:
March 15, 2003
Committee Members:
Elizabeth Susman, Committee Member Alan Booth, Committee Member Douglas A Granger, Committee Chair/Co-Chair Laura Klein, Committee Member William L Harkness, Committee Member Scott Hofer, Committee Member
Research linking basal cortisol levels with internalizing and externalizing behavior problems in youth has yielded inconsistent results. We hypothesize that the high moment-to-moment variation in adrenocortical activity requires an analytical strategy that separates variance in cortisol levels attributable to “stable trait-like” versus “state or situationally specific” sources. Early morning saliva samples were obtained from 654 youth (M age = 13.5 yrs; range 6-16 yrs in year 1) on two successive days one year apart. Latent state-trait modeling revealed that 70% of the variance in cortisol levels could be attributed to state- like sources, and 28% to trait-like sources. For boys only, higher levels of externalizing problem behaviors were consistently associated with lower cortisol attributable to trait-like sources across all three years of behavioral assessment. The inverse association between individual differences in cortisol and externalizing problem behavior has previously only been reported in studies of at-risk or clinical groups. The present findings suggest the relationship is a stable phenomenon that spans both normative and atypical child development. Studies are needed to reveal the biosocial mechanisms involved in the establishment and maintenance of this phenomenon, and to decipher whether individual differences in this hormone-behavior link confers risk or resilience.
