title: Bone mineral density is reduced in brain tumour patients treated in childhood.
abstract: OBJECTIVE
  To determine the prevalence of low bone mineral density among children surviving brain tumours and to identify possible factors underlying impaired bone health.
  
  
  METHODS
  Cross-sectional study; total body bone mineral density (TBBMD), fat mass (FM) and lean body mass (LBM) were measured by dual-energy X-ray absorptiometry (DXA) in 46 brain tumour patients aged from 3.8 to 28.7 y (mean 14.9 y) treated in childhood 1.4-14.8 y (mean 6.4 y) after end of treatment for brain tumour. Low bone mineral density was defined as TBBMD z score < - 2.0.
  
  
  RESULTS
  Fifteen patients had TBBMD z scores < - 2.0, indicating a 33% prevalence of low bone density. The TBBMD z score ranged from -5.7 to 0.6 (mean -1.7). Out of several potential factors, only combined craniospinal irradiation was significantly associated with low z score (p=0.034, according to multiple regression analysis), while exclusive cranial irradiation showed a borderline statistical association (p=0.100, according to multiple regression analysis).
  
  
  CONCLUSIONS
  One third of brain tumour patients treated in childhood had reduced bone mineral density. The reasons for this condition are apparently multifactorial, including craniospinal irradiation.
authors.affiliation: Department of Paediatrics, Tampere University Hospital, Tampere, Finland. sari.pietila@sci.fi
authors.forename: Sari
authors.initials: S
authors.lastname: Pietilä
authors.forename: Harri
authors.initials: H
authors.lastname: Sievänen
authors.forename: Marja
authors.initials: M
authors.lastname: Ala-Houhala
authors.forename: Anna-Maija
authors.initials: AM
authors.lastname: Koivisto
authors.forename: Hanna
authors.initials: H
authors.lastname: Liisa Lenko
authors.forename: Anne
authors.initials: A
authors.lastname: Mäkipernaa
mesh_terms: D015519:Bone Density / Q000528:radiation effects; D001851:Bone Diseases, Metabolic / Q000453:epidemiology; D001932:Brain Neoplasms / Q000453:epidemiology / Q000503:physiopathology* / Q000532:radiotherapy; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D011878:Radiotherapy / Q000009:adverse effects