title: Non-invasive endothelial function assessment in patients with neurofibromatosis type 1: a cross-sectional study.
abstract: BACKGROUND
  Neurofibromatosis type 1 (NF1) is a multi-systemic disease caused by neurofibromin deficiency. The reduced life expectancy of patients with NF1 has been attributed to NF1-associated malignant neoplasms. However, an analysis of death certificates in the USA suggests that vascular disease could be an important cause of early death among these patients. Endothelial dysfunction (ED) is related to vasculopathy and is an early marker of subclinical atherosclerosis. Since neurofibromin has already been demonstrated to affect endothelial cell function, ED may be associated with NF1. The purpose of this study was to assess endothelial function in patients with NF1 using a non-invasive method.
  
  
  METHODS
  NF1 patients and healthy control subjects, aged 18 to 35 years, were included. Subjects were excluded if they had any risk factor for vascular disease or any other condition known to affect endothelial function. Endothelial function was assessed using reactive hyperemia-peripheral arterial tone (RH-PAT) technology. ED was defined as a reactive hyperemia index (RHI) lower than 1.35.
  
  
  RESULTS
  Four of the 29 (13.8%) NF1 patients and 1 of the 30 (3.3%) healthy volunteers had ED (p=0.153). RHI medians and interquartile intervals were 1.8 (1.58-2.43) for the NF1 group and 2.02 (1.74-2.49) for the control group (p=0.361).
  
  
  CONCLUSIONS
  The prevalence of ED was similar in NF1 patients and healthy controls.
authors.affiliation: Department of Internal Medicine, Federal University of Minas Gerais, Av, Prof, Alfredo Balena, 190-246, Belo Horizonte, MG, Cep:30130-100, Brazil. draluizarodrigues@gmail.com
authors.forename: Luiza O
authors.initials: LO
authors.lastname: Rodrigues
authors.forename: Luiz Oswaldo C
authors.initials: LO
authors.lastname: Rodrigues
authors.forename: Luisa Lima
authors.initials: LL
authors.lastname: Castro
authors.forename: Nilton A
authors.initials: NA
authors.lastname: Rezende
authors.forename: Antonio Luiz P
authors.initials: AL
authors.lastname: Ribeiro
mesh_terms: D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D004730:Endothelium, Vascular / Q000503:physiopathology*; D005260:Female; D006801:Humans; D006940:Hyperemia / Q000503:physiopathology; D008297:Male; D008365:Manometry; D009456:Neurofibromatosis 1 / Q000150:complications* / Q000503:physiopathology; D011237:Predictive Value of Tests; D014652:Vascular Diseases / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D055815:Young Adult