title: Prevalence of and risk factors for osteoporosis in adults with acquired brain injury.
abstract: BACKGROUND
  Low bone mineral density (BMD) is common in older people with stroke, particularly in the paretic limb. Younger people with acquired brain injury (ABI), of all causes, are at increased risk of low BMD.
  
  
  OBJECTIVE
  To examine prevalence of low BMD, based on World Health Organisation diagnostic criteria, in patients with ABI.
  
  
  METHODS
  This is a cross-sectional study of 112 ABI patients. All completed a questionnaire, had laboratory investigations and DXA assessment of lumbar spine and one or both hips.
  
  
  RESULTS
  Mean age ± SD of participants was 45.7 ± 13.7 years. Risk of vitamin D deficiency (25-OHD < 30 nmol/L) occurred in 27.7 %, 34.3 % had adequate levels (30-50 nmol/L) and 36.6 % had levels in excess of this. Based on T-scores, 41.1 % had osteopenia and 21.4 % had osteoporosis. A Z score of -1 or less but greater than -2 occurred in 25 %; a further 21.4 % had a Z score of -2 or less. Patients who could walk outdoors had significantly higher BMD at the neck of femur than those who walked indoors only and those who could not walk at all (p < 0.001). On multiple linear regression analysis, ambulatory ability and duration of disability were independent predictors of BMD at sound neck of femur and total proximal femur.
  
  
  CONCLUSIONS
  Osteopenia and osteoporosis are common in young adults with ABI compared with the general population. Bone heath monitoring should form part of the long-term follow-up of this patient group.
authors.affiliation: Department of Rehabilitation Medicine, National Rehabilitation Hospital, Rochestown Ave., Dún Laoghaire, Co. Dublin, Ireland. eimear.smith@nrh.ie.
authors.forename: É
authors.initials: É
authors.lastname: Smith
authors.affiliation: Health Care Statistics, School of Nursing and Midwifery, Trinity College Dublin, The Gas Building, D'Olier St., Dublin 2, Ireland.
authors.forename: C
authors.initials: C
authors.lastname: Comiskey
authors.affiliation: Department of Rehabilitation Medicine, National Rehabilitation Hospital, Rochestown Ave., Dún Laoghaire, Co. Dublin, Ireland.
authors.forename: Á
authors.initials: Á
authors.lastname: Carroll
mesh_terms: D015502:Absorptiometry, Photon; D000328:Adult; D015519:Bone Density; D001851:Bone Diseases, Metabolic / Q000453:epidemiology*; D001930:Brain Injuries / Q000150:complications*; D003430:Cross-Sectional Studies; D006233:Persons with Disabilities; D005260:Female; D006801:Humans; D008159:Lumbar Vertebrae; D008297:Male; D008875:Middle Aged; D010024:Osteoporosis / Q000175:diagnosis / Q000453:epidemiology*; D015995:Prevalence; D012307:Risk Factors; D011795:Surveys and Questionnaires; D014808:Vitamin D Deficiency / Q000453:epidemiology; D016138:Walking
keywords: Acquired brain injury; Dual energy X-ray absorptiometry; Fracture risk; Osteoporosis; Stroke; Traumatic brain injury