title: Examination of the potential association of stress with morbidity and mortality outcomes in patient with heart failure.
abstract: OBJECTIVE
  The high mortality and morbidity rates associated with heart failure are still not well explained. A few psychosocial factors have been studied and explain some of this risk, but other factors, like stress, remain largely unexplored in heart failure. This study aimed to (1) examine the association of stress with 6-month cardiac event-free survival, (2) examine the relationship of stress with salivary cortisol, and (3) examine the association of salivary cortisol level with 6-month cardiac event-free survival.
  
  
  METHODS
  A total of 81 heart failure patients participated. Stress was measured using the brief Perceived Stress Scale. Cortisol was measured from unstimulated whole expectorated saliva. Cox regression analyses were used to determine whether stress predicted event-free survival, and if salivary cortisol predicted event-free survival. Linear and multiple regressions were used to determine the association of stress with salivary cortisol.
  
  
  RESULTS
  Stress was not a significant predictor of event-free survival in heart failure (heart rate = 1.06; 95% confidence interval = 0.95-1.81; p = 0.32). Salivary cortisol was a significant predictor of event-free survival in the unadjusted model (heart rate = 2.30; 95% confidence interval = 0.99-5.927; p = 0.05), but not in the adjusted model. Stress (β 1.06; 95% confidence interval = 0.95-1.18; p = 0.32) was not a significant predictor of salivary cortisol level.
  
  
  CONCLUSIONS
  Stress is a complex phenomenon, and our measure of stress may not have captured it well. Alternatively, the physical stressors acting in heart failure produce levels of neurohormonal activation that mask the effects of psychosocial stressors or an indirect association of stress with outcomes that is mediated through another construct. Future studies are needed to investigate stress in patients with heart failure to provide definitive answers.
authors.affiliation: College of Nursing, University of Kentucky, Lexington, KY, USA ; The University of Jordan, Amman, Jordan.
authors.forename: Abdullah S
authors.initials: AS
authors.lastname: Alhurani
authors.affiliation: College of Nursing, University of Kentucky, Lexington, KY, USA.
authors.forename: Rebecca
authors.initials: R
authors.lastname: Dekker
authors.affiliation: College of Nursing, University of Kentucky, Lexington, KY, USA.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Tovar
authors.affiliation: College of Nursing, University of Kentucky, Lexington, KY, USA.
authors.forename: Alison
authors.initials: A
authors.lastname: Bailey
authors.affiliation: College of Nursing, University of Kentucky, Lexington, KY, USA.
authors.forename: Terry A
authors.initials: TA
authors.lastname: Lennie
authors.affiliation: College of Nursing, University of Kentucky, Lexington, KY, USA.
authors.forename: David C
authors.initials: DC
authors.lastname: Randall
authors.affiliation: College of Nursing, University of Kentucky, Lexington, KY, USA.
authors.forename: Debra K
authors.initials: DK
authors.lastname: Moser
keywords: Stress; cortisol; event-free survival; health outcomes; heart failure