title: Cross-country differences in basal and stress-induced cortisol secretion in older adults.
abstract: OBJECTIVE
  Several studies have emphasized the association between socioeconomic status (SES) and inadequate response of the biological stress system. However, other factors related to SES are rarely considered, such as cultural values, social norms, organization, language and communication skills, which raises the need to investigate cross-country differences in stress response. Although some studies have shown differences in cortisol levels between immigrants and natives, there is no cross-country evidence regarding cortisol levels in country-native elders. This is particularly important given the high prevalence of stress-related disorders across nations during aging. The current study examined basal diurnal and reactive cortisol levels in healthy older adults living in two different countries.
  
  
  METHODS
  Salivary cortisol of 260 older adults from Canada and Brazil were analyzed. Diurnal cortisol was measured in saliva samples collected at home throughout two working days at awakening, 30 min after waking, 1400 h, 1600 h and before bedtime. Cortisol reactivity was assessed in response to the Trier Social Stress Test (TSST) in both populations.
  
  
  RESULTS
  Our results showed that even under similar health status, psychological and cognitive characteristics, Brazilian elders exhibited higher basal and stress-induced cortisol secretion compared to the Canadian participants.
  
  
  CONCLUSIONS
  These findings suggest that country context may modulate cortisol secretion and could impact the population health.
authors.affiliation: Department of Medical-Surgical Nursing, School of Nursing, Universidade de São Paulo, São Paulo, Brazil; Department of Psychobiology, Universidade Federal de São Paulo, São Paulo, Brazil.
authors.forename: Juliana N
authors.initials: JN
authors.lastname: Souza-Talarico
authors.affiliation: School of Psychoeducation, Université de Montréal, Montreal, Quebec, Canada; Centre for Studies on Human Stress, Mental Health Institute of Montréal Research Center, Department of Psychiatry, Université de Montréal, Montréal, Quebec, Canada.
authors.forename: Pierrich
authors.initials: P
authors.lastname: Plusquellec
authors.affiliation: Centre for Studies on Human Stress, Mental Health Institute of Montréal Research Center, Department of Psychiatry, Université de Montréal, Montréal, Quebec, Canada.
authors.forename: Sonia J
authors.initials: SJ
authors.lastname: Lupien
authors.affiliation: Department of Psychology, Ryerson University, Toronto, Ontario, Canada.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Fiocco
authors.affiliation: Department of Psychobiology, Universidade Federal de São Paulo, São Paulo, Brazil.
authors.forename: Deborah
authors.initials: D
authors.lastname: Suchecki
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging; D001938:Brazil; D002170:Canada; D005260:Female; D006304:Health Status; D006801:Humans; D006854:Hydrocortisone / Q000032:analysis*; D007030:Hypothalamo-Hypophyseal System / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D010913:Pituitary-Adrenal System / Q000503:physiopathology*; D012463:Saliva / Q000737:chemistry; D013315:Stress, Psychological / Q000503:physiopathology*
chemical_list: D006854:Hydrocortisone