title: Bone mineral density in children and adolescents with neurofibromatosis type 1.
abstract: OBJECTIVE
  To assess whether children and adolescents with neurofibromatosis type 1 (NF1) have decreased bone mineral density (BMD).
  
  
  METHODS
  Bone densitometry of the whole body, hip, and lumbar spine was used in a case-to-control design (84 individuals with NF1: 293 healthy individuals without NF1). Subjects were 5 to 18 years old. Subjects with NF1 were compared with control subjects by using an analysis-of-covariance with a fixed set of covariates (age, weight, height, Tanner stage, and sex).
  
  
  RESULTS
  Subjects with NF1 had decreased areal BMD (aBMD) of the hip (P <.0001), femoral neck (P <.0001), lumbar spine (P = .0025), and whole body subtotal (P <.0001). When subjects with NF1 were separated in groups with and without a skeletal abnormality, those who did not have a skeletal abnormality still had statistically significant decreases in aBMD compared with control subjects (P <.0001 for whole body subtotal aBMD), although they were less pronounced than in those with osseous abnormalities.
  
  
  CONCLUSIONS
  These data suggest that individuals with NF1 have a unique generalized skeletal dysplasia, predisposing them to localized osseous defects. Dual energy x-ray absorptiometry may prove useful in identifying individuals with NF1 who are at risk for clinical osseous complications and monitoring therapeutic trials.
authors.affiliation: Department of Pediatrics, University of Utah, Salt Lake City, Utah 84132, USA. david.stevenson@hsc.utah.edu
authors.forename: David A
authors.initials: DA
authors.lastname: Stevenson
authors.forename: Laurie J
authors.initials: LJ
authors.lastname: Moyer-Mileur
authors.forename: Mary
authors.initials: M
authors.lastname: Murray
authors.forename: Hillarie
authors.initials: H
authors.lastname: Slater
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Sheng
authors.forename: John C
authors.initials: JC
authors.lastname: Carey
authors.forename: Bukhosi
authors.initials: B
authors.lastname: Dube
authors.forename: David H
authors.initials: DH
authors.lastname: Viskochil
mesh_terms: D015502:Absorptiometry, Photon; D000293:Adolescent; D000367:Age Factors; D015519:Bone Density / Q000502:physiology*; D002648:Child; D002675:Child, Preschool; D018450:Disease Progression; D005260:Female; D006615:Hip / Q000000981:diagnostic imaging; D006801:Humans; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging; D008297:Male; D009456:Neurofibromatosis 1 / Q000000981:diagnostic imaging / Q000378:metabolism*; D011379:Prognosis; D012720:Severity of Illness Index; D012737:Sex Factors