title: Impaired vascular function in asymptomatic young adult survivors of Hodgkin Lymphoma following mediastinal radiation.
abstract: BACKGROUND
  Mediastinal radiation can accelerate atherosclerosis in Hodgkin lymphoma survivors (HLS), and early detection is optimal. Peripheral arterial tonometry (PAT), a non-invasive measure of endothelial function, is a surrogate marker of sub-clinical atherosclerosis. The objective of our study was to evaluate endothelial function in HLS and controls using PAT and to determine the influence of mediastinal radiation.
  
  
  METHODS
  Cross-sectional evaluation was performed on 26 HLS aged 12-30 years who were a minimum of 2 years from therapy, and their healthy age and gender matched controls. Evaluation included assessment for cardiovascular risk factors and completion of the Habitual Activity Estimation Score (HAES) questionnaire to assess activity level. Endothelial Function was measured using PAT hyperemia ratios (PAT-HR).
  
  
  RESULTS
  HLS and controls were similar for baseline variables (mean age 23.3 +/- 5 yrs vs. 23.4 +/- 4.8 yrs, p = 0.92). HLS were on average 6.7 +/- 4.6 yrs post treatment. No differences in endothelial function or cardiovascular risk factors were observed between HLS and controls. However, impaired endothelial function, as evidenced by lower PAT-HR (1.67 +/- 0.39 vs. 2.03 +/- 0.37, p < 0.01) was seen in HLS (n = 13) who received mediastinal radiation (mean radiation dose 2,600 +/- 840 cGy) compared to controls.
  
  
  CONCLUSIONS
  Impaired endothelial function was preferentially observed in HLS who received mediastinal radiation, while no difference was observed between the HLS and control groups overall. This finding, assessed using a non invasive test of endothelial function, confirms that mediastinal radiation is an additional cardiovascular risk factor in this young cohort of patients. Further studies of endothelial function in this patient population are warranted.
authors.affiliation: Children's Hospital, London Health Sciences Center, ON, Canada. shayna.zelcer@lhsc.on.ca
authors.forename: Shayna
authors.initials: S
authors.lastname: Zelcer
authors.forename: Breanna
authors.initials: B
authors.lastname: Chen
authors.forename: Joy
authors.initials: J
authors.lastname: Mangel
authors.forename: Olga
authors.initials: O
authors.lastname: Vujovic
authors.forename: Heather R
authors.initials: HR
authors.lastname: Thiessen-Philbrook
authors.forename: Michael
authors.initials: M
authors.lastname: Reider
authors.forename: Farid H
authors.initials: FH
authors.lastname: Mahmud
mesh_terms: D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D002648:Child; D003430:Cross-Sectional Studies; D004730:Endothelium, Vascular / Q000503:physiopathology*; D005260:Female; D006689:Hodgkin Disease / Q000473:pathology / Q000532:radiotherapy*; D006801:Humans; D008297:Male; D008479:Mediastinal Neoplasms / Q000473:pathology / Q000532:radiotherapy*; D010865:Pilot Projects; D011836:Radiation Tolerance; D012189:Retrospective Studies; D012307:Risk Factors; D017741:Survivors; D014652:Vascular Diseases / Q000503:physiopathology*; D055815:Young Adult