title: Time control, catecholamines and back pain among young nurses.
abstract: OBJECTIVE
  This study had two objectives. First, it addressed concern with the contribution of work stressors and resources to the development of back pain, over and above the influence of biomechanical work factors. Second, using recent models about the role of the sympathetic-adrenal medullar system in musculoskeletal problems as its basis, it tested whether low-back pain is associated with higher levels of catecholamines.
  
  
  METHODS
  Altogether 114 nurses filled out a questionnaire in their first year of practice and again one year later. In addition, in a subsample of 24 nurses studied intensively at follow-up, urinary catecholamines were assessed at noon, before the end of work, in the evening, and at corresponding times on a day off. Daily stressful experiences and daily mood were also recorded.
  
  
  RESULTS
  With control for baseline pain, biomechanical workload, and other potentially confounding variables, time control at the beginning of the study predicted low-back pain a year later. In the subsample, the epinephrine and norepinephrine levels were higher in those reporting more frequent episodes of back pain, the largest differences occurring at the end of work. In addition, control over stressful events at work was lower in this group.
  
  
  CONCLUSIONS
  Time control is a risk factor for low-back pain among nurses beyond the influence of physical work load. Low control at work may increase the activity of the sympathetic-adrenal medullar system, which seems to play an important role in the development of musculoskeletal pain.
authors.affiliation: Department of Psychology, University of Berne, Berne, Switzerland. achim.elfering@psy.unibe.ch
authors.forename: Achim
authors.initials: A
authors.lastname: Elfering
authors.forename: Simone
authors.initials: S
authors.lastname: Grebner
authors.forename: Norbert K
authors.initials: NK
authors.lastname: Semmer
authors.forename: Hans
authors.initials: H
authors.lastname: Gerber
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D002395:Catecholamines / Q000652:urine*; D004837:Epinephrine / Q000652:urine; D006801:Humans; D008137:Longitudinal Studies; D017116:Low Back Pain / Q000453:epidemiology* / Q000503:physiopathology / Q000652:urine; D009726:Nurses / Q000523:psychology* / Q000706:statistics & numerical data; D009784:Occupational Diseases / Q000453:epidemiology* / Q000503:physiopathology / Q000652:urine; D012307:Risk Factors; D012944:Social Support; D013315:Stress, Psychological / Q000503:physiopathology / Q000652:urine; D011795:Surveys and Questionnaires; D013557:Switzerland / Q000453:epidemiology
chemical_list: D002395:Catecholamines; D004837:Epinephrine