title: Stress-related thinking predicts the cortisol awakening response and somatic symptoms in healthy adults.
abstract: OBJECTIVE
  Perseverative cognition (i.e., worry, stress-related thinking) may prolong stress-related physiological activation. However, its role within the context of the written emotional disclosure paradigm has not been examined. This study explored: (1) the effects of stress-related thinking on the cortisol awakening response and upper respiratory infection symptoms and; (2) the efficacy of two expressive writing interventions on these health outcomes.
  
  
  METHODS
  Participants were randomly assigned to write about their most stressful life experience (using the Guided Disclosure Protocol; n=39) or positive life experiences (n=42) or plans for the day (n=41) for 20 min on 3 consecutive days. Participants reported the extent to which they thought about their assigned writing topic during the study and in the past (event-related thought). Cortisol was measured at 0, 15, 30 and 45 min after awakening on 2 consecutive days at baseline and 4 weeks post-intervention. Upper respiratory infection (URI) symptoms were assessed at baseline, at 4 weeks and at 6 months.
  
  
  RESULTS
  Results showed that the writing interventions had no beneficial effects on any of the outcome measures. However, a significant interaction was found between event-related thought and condition on the cortisol awakening response at 1 month follow-up and URI symptoms at 6 months. Among participants who wrote about stressful/traumatic events, higher stress-related thinking during the study predicted increased cortisol levels and URI symptoms compared to participants who reported low stress-related thinking.
  
  
  CONCLUSIONS
  These findings are broadly consistent with Brosschot et al.'s (2006) perseverative cognition hypothesis and highlight the importance of ruminative thinking in understanding stress-health processes.
authors.affiliation: Institute of Psychological Sciences, University of Leeds, Leeds LS29JT, UK. d.b.o'connor@leeds.ac.uk
authors.forename: Daryl B
authors.initials: DB
authors.lastname: O'Connor
authors.forename: Sarah
authors.initials: S
authors.lastname: Walker
authors.forename: Hilde
authors.initials: H
authors.lastname: Hendrickx
authors.forename: Duncan
authors.initials: D
authors.lastname: Talbot
authors.forename: Alexandre
authors.initials: A
authors.lastname: Schaefer
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism*; D008016:Life Change Events; D008297:Male; D010912:Pituitary-Adrenal Function Tests / Q000379:methods; D012141:Respiratory Tract Infections / Q000150:complications / Q000175:diagnosis*; D012463:Saliva / Q000378:metabolism; D013315:Stress, Psychological / Q000150:complications / Q000378:metabolism* / Q000523:psychology*; D013850:Thinking; D014851:Wakefulness; D014956:Writing
chemical_list: D006854:Hydrocortisone