title: Exploring salivary cortisol and recurrent pain in mid-adolescents living in two homes.
abstract: BACKGROUND
  Each year, around 50.000 children in Sweden experience a separation between their parents. Joint physical custody (JPC), where the child alternates homes between the parents for about equal amount of time, has become a common living arrangement after parental separation. Children in two homes could benefit from everyday contact with both parents and access to both parents' financial resources. However, children could experience stress from being constantly moving and potentially exposed to parental conflicts. Still, studies on JPC and biological functioning related to stress, are lacking. The aim of this study was to investigate how living arrangements (intact family/JPC) relate to HPA-axis activity and recurrent pain in mid-adolescents.
  
  
  METHODS
  Mid-adolescents (106 girls and 51 boys) provided demographic details, self-reports of recurrent pain (headache, stomachache, neck/shoulder and back pain) and salivary samples. Salivary cortisol samples were collected: 1) immediately at awakening, 2) +30 minutes, 3) +60 minutes, and 4) at 8 p.m. The cortisol awakening response (CAR) was computed using an established formula. Additionally, the diurnal decline between the waking and 8 p.m. samples was computed.
  
  
  RESULTS
  Hierarchical multiple regressions showed that living arrangements (intact family/JPC) was not associated with morning cortisol (CAR), the diurnal cortisol decline or with recurrent pain. However, sex was a significant predictor of both cortisol measures and recurrent pain with girls exhibiting a higher cortisol awakening response and a greater diurnal decline value as well as reporting more recurrent pain than did boys.
  
  
  CONCLUSIONS
  Living arrangements were not associated with HPA-axis activity or recurrent pain in this group of well-functioning mid-adolescents. Although this study is the first to investigate how living arrangements relate to HPA-axis functioning and additional studies are needed, the tentative findings suggest that these mid-adolescents have adapted to their living arrangements and that other factors play a more pertinent role for HPA-functioning and subjective health.
authors.affiliation: Centre for Health Equity Studies (CHESS), Stockholm University/Karolinska institutet, 106 90 Stockholm, Sweden.
authors.forename: Emma
authors.initials: E
authors.lastname: Fransson
authors.affiliation: Centre for Health Equity Studies (CHESS), Stockholm University/Karolinska institutet, 106 90 Stockholm, Sweden ; Department of Psychology, Stockholm University, Stockholm, Sweden.
authors.forename: Lisa
authors.initials: L
authors.lastname: Folkesson
authors.affiliation: Centre for Health Equity Studies (CHESS), Stockholm University/Karolinska institutet, 106 90 Stockholm, Sweden.
authors.forename: Malin
authors.initials: M
authors.lastname: Bergström
authors.affiliation: Centre for Health Equity Studies (CHESS), Stockholm University/Karolinska institutet, 106 90 Stockholm, Sweden.
authors.forename: Viveca
authors.initials: V
authors.lastname: Östberg
authors.affiliation: Department of Psychology, Stockholm University, Stockholm, Sweden.
authors.forename: Petra
authors.initials: P
authors.lastname: Lindfors
keywords: Cortisol; HPA-axis activity; Joint physical custody; Mid-adolescence; Recurrent pain