title: The effect of an adverse psychological environment on salivary cortisol levels in the elderly differs by5-HTTLPRgenotype.
abstract: BACKGROUND
  An adverse psychological environment (e.g. stressful events or depression) has been shown to influence basal cortisol levels and cortisol response to stress. This differs depending on the adverse stimuli, but also varies across individuals and may be influenced by genetic predisposition. An insertion/deletion polymorphism in the serotonin transporter gene (5-HTTLPR) is a strong candidate in this regard.
  
  
  OBJECTIVE
  To investigate how stressful life events and depression are associated with diurnal cortisol levels in community-dwelling elderly and determine whether this varies according to genetic variability in the5-HTTLPR.
  
  
  METHODS
  This population-based study included 334 subjects aged 65 and older (mean (SD) = 76.5 (6.3)). Diurnal cortisol was measured on two separate days, under quiet (basal) and stressful conditions. The number of recent major stressful events experienced during the past year was assessed from a 12-item validated questionnaire as an index of cumulative recent stressful events. Lifetime trauma was evaluated using the validated Watson's PTSD inventory, which evaluates the most severe traumatic or frightening experience according to DSM criteria. Depression was defined as having a Mini-International Neuropsychiatric Interview (MINI) diagnosis of current major depressive disorder or high levels of depressive symptoms (Center for Epidemiologic Studies-Depression Scale ≥16).5-HTTLPRgenotyping was performed on blood samples.
  
  
  RESULTS
  Exposure to stressful life events was associated with lower basal evening cortisol levels overall, and in the participants with the5-HTTLPR Lallele but not theSSgenotype. The greatest effects (over 50% decrease, p < 0.001) were observed for theLLparticipants having experienced multiple recent stressful events or severe lifetime traumas. Participants with theLallele also had higher evening cortisol stress response. Conversely, depression tended to be associated with a 42% higher basal morning cortisol in theSSparticipants specifically, but did not modify the association between stressful events and cortisol levels.
  
  
  CONCLUSIONS
  An adverse psychological environment is associated with basal cortisol levels and cortisol stress response, but this differs according to5-HTTLPRgenotype.
authors.affiliation: Inserm, U1061, Montpellier, France; University of Montpellier, Montpellier, France.
authors.forename: Marie-Laure
authors.initials: ML
authors.lastname: Ancelin
authors.affiliation: Inserm, U1061, Montpellier, France; University of Montpellier, Montpellier, France.
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Scali
authors.affiliation: Inserm, U1061, Montpellier, France; University of Montpellier, Montpellier, France.
authors.forename: Joanna
authors.initials: J
authors.lastname: Norton
authors.affiliation: Inserm, U1061, Montpellier, France; University of Montpellier, Montpellier, France; Center for Clinical Brain Sciences, University of Edinburgh, UK.
authors.forename: Karen
authors.initials: K
authors.lastname: Ritchie
authors.affiliation: Inserm, U1061, Montpellier, France; University of Montpellier, Montpellier, France; Lapeyronie University Hospital, Montpellier, France.
authors.forename: Anne-Marie
authors.initials: AM
authors.lastname: Dupuy
authors.affiliation: Inserm, U1061, Montpellier, France; University of Montpellier, Montpellier, France.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Chaudieu
authors.affiliation: Inserm, U1061, Montpellier, France; University of Montpellier, Montpellier, France; Disease Epigenetics Group, Murdoch Children's Research Institute and Department of Paediatrics, The University of Melbourne, Parkville, Australia; Department of Epidemiology and Preventative Medicine, School of Public Health and Preventative Medicine, Monash University, Prahran, Australia.
authors.forename: Joanne
authors.initials: J
authors.lastname: Ryan
keywords: Adverse events; Depression; Hypothalamic-pituitary-adrenal axis; Serotonin transporter-linked promoter region; Stress response; Trauma