title: The development of depressive symptoms during medical internship stress predicts worsening vascular function.
abstract: OBJECTIVE
  We sought to prospectively determine whether the onset of internship stress and any subsequent depression alters physiological markers of early vascular disease
  
  
  METHODS
  We explored potential mechanisms linking stress and depression to vascular disease in a prospective cohort of 37 participants exposed to medical internship stress, an established precipitant of depressive symptomatology.
  
  
  RESULTS
  Change in depressive symptom score from baseline over one year of internship stress was inversely correlated with change in the reactive hyperemia index (RHI), a measure of peripheral endothelial function (r=0.41, p=0.01). The change in depressive symptoms in the first six months of internship was similarly related to change in RHI over one year (r=0.38, p=0.02). While the development of depressive symptoms did not significantly impact changes in endothelial progenitor cells (EPCs), EPCs did significantly decrease with the year of internship stress (11.9 to 3.4cells/ml blood; p=0.01).
  
  
  CONCLUSIONS
  Endothelial function may be a critical link between stress, depression, and cardiovascular disease and a feasible surrogate outcome for prospective studies.
authors.affiliation: Department of Psychiatry, The University of Iowa, Iowa City, IA, United States; Department of Internal Medicine, Carver College of Medicine, The University of Iowa, Iowa City, IA, United States; Department of Epidemiology, College of Public Health, The University of Iowa, Iowa City, IA, United States.
authors.forename: Jess G
authors.initials: JG
authors.lastname: Fiedorowicz
authors.affiliation: College of Pharmacy, University of Michigan, Ann Arbor, MI, United States; Department of Psychiatry, University of Michigan, Ann Arbor, MI, United States.
authors.forename: Vicki L
authors.initials: VL
authors.lastname: Ellingrod
authors.affiliation: Systemic Autoimmunity Branch, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD, United States.
authors.forename: Mariana J
authors.initials: MJ
authors.lastname: Kaplan
authors.affiliation: Department of Psychiatry, University of Michigan, Ann Arbor, MI, United States; Molecular and Behavioral Neuroscience Institute, Department of Psychiatry, University of Michigan, Ann Arbor, MI, United States. Electronic address: srijan@umich.edu.
authors.forename: Srijan
authors.initials: S
authors.lastname: Sen
mesh_terms: D000328:Adult; D002319:Cardiovascular System / Q000503:physiopathology*; D003863:Depression / Q000523:psychology*; D005260:Female; D006801:Humans; D006940:Hyperemia / Q000523:psychology*; D007396:Internship and Residency; D008297:Male; D011446:Prospective Studies; D013315:Stress, Psychological / Q000150:complications*; D013337:Students, Medical / Q000523:psychology*; D014652:Vascular Diseases / Q000503:physiopathology / Q000523:psychology*
keywords: Biological makers; Cardiovascular diseases; Endothelial function; Major depressive disorder