title: A pilot study of change in fracture risk in patients with acute respiratory distress syndrome.
abstract: BACKGROUND
  Acute skeletal muscle wasting is a major contributor to post critical illness physical impairment. However, the bone response remains uncharacterized. We prospectively investigated the early changes in bone mineral density (BMD) and fracture risk in critical illness.
  
  
  METHODS
  Patients were prospectively recruited ≤24 hours following intensive care unit (ICU) admission to a university teaching or a community hospital (August 2009 to April 2011). All were aged >18 years and expected to be intubated for >48 hours, spend >7 days in critical care and survive ICU admission. Forty-six patients were studied (55.3% male), with a mean age of 54.4 years (95% confidence interval (CI): 49.1 to 59.6) and an APACHE II score of 23.9 (95% CI: 22.4 to 25.5). Calcaneal dual X-ray absorptiometry (DXA) assessment of BMD was performed on day 1 and 10. Increase in fracture risk was calculated from the change in T-score.
  
  
  RESULTS
  BMD did not change between day 1 and 10 in the cohort overall (0.434 (95% CI: 0.405 to 0.463) versus 0.425 g/cm(2) (95% CI: 0.399 to 0.450), P = 0.58). Multivariable logistical regression revealed admission corrected calcium (odds ratio (OR): 1.980 (95% CI: 1.089 to 3.609), P = 0.026) and admission PaO2-to-FiO2 ratio (OR: 0.916 (95% CI: 0.833 to 0.998), P = 0.044) to be associated with >2% loss of BMD. Patients with acute respiratory distress syndrome had a greater loss in BMD than those without (-2.81% (95% CI: -5.73 to 0.118%), n = 34 versus 2.40% (95% CI: 0.204 to 4.586%), n = 12, P = 0.029). In the 34 patients with acute respiratory distress syndrome, fracture risk increased by 19.4% (95% CI: 13.9 to 25.0%).
  
  
  CONCLUSIONS
  Patients with acute respiratory distress syndrome demonstrated early and rapid bone demineralisation with associated increase in fracture risk.
authors.affiliation: Institute of Health and Human Performance, University College London, Room 443, 74 Huntley Street, London, WC1E 6AU, UK. jrawal@mac.com.
authors.forename: Jaikitry
authors.initials: J
authors.lastname: Rawal
authors.affiliation: Department of Hepatology and Gastroenterology, St Mary's Hospital, Imperial College London, praed street, London, W2 1NY, UK. mark.mcphail@csc.mrc.ac.uk.|Institute of Liver Studies, King's College Hospital NHS Foundation Trust, denmark hill, London, SE59RS, UK. mark.mcphail@csc.mrc.ac.uk.
authors.forename: Mark J W
authors.initials: MJ
authors.lastname: McPhail
authors.affiliation: NIHR Comprehensive Biomedical Research Centre, Guy's and St Thomas' NHS Foundation Trust and King's College London, Westminster Bridge Road, London, SE17EH, UK. rgamrat@googlemail.com.
authors.forename: Gamumu
authors.initials: G
authors.lastname: Ratnayake
authors.affiliation: Institute of Health and Human Performance, University College London, Room 443, 74 Huntley Street, London, WC1E 6AU, UK. pearlchan@doctors.org.uk.
authors.forename: Pearl
authors.initials: P
authors.lastname: Chan
authors.affiliation: King's College London School of Medicine, denmark hill, London, SE59RS, UK. john.moxham@nhs.net.
authors.forename: John
authors.initials: J
authors.lastname: Moxham
authors.affiliation: Centre of Human and Aerospace Physiological Sciences, King's College London, Great Maze Pond, London, SE1 9RT, UK. s.harridge@kcl.ac.uk.
authors.forename: Stephen D R
authors.initials: SD
authors.lastname: Harridge
authors.affiliation: NIHR Comprehensive Biomedical Research Centre, Guy's and St Thomas' NHS Foundation Trust and King's College London, Westminster Bridge Road, London, SE17EH, UK. Nicholas.hart@gstt.nhs.uk.
authors.forename: Nicholas
authors.initials: N
authors.lastname: Hart
authors.affiliation: Institute of Health and Human Performance, University College London, Room 443, 74 Huntley Street, London, WC1E 6AU, UK. h.montgomery@ucl.ac.uk.
authors.forename: Hugh E
authors.initials: HE
authors.lastname: Montgomery
authors.affiliation: Institute of Health and Human Performance, University College London, Room 443, 74 Huntley Street, London, WC1E 6AU, UK. Zudin_amilka_puthucheary@nuhs.edu.sg.|Division of Respiratory and Critical Care, National University Hospital, 1E Lower Kent Ridge Road, Singapore, 119228, Singapore. Zudin_amilka_puthucheary@nuhs.edu.sg.
authors.forename: Zudin A
authors.initials: ZA
authors.lastname: Puthucheary
mesh_terms: D015502:Absorptiometry, Photon; D000328:Adult; D000368:Aged; D018488:Bone Demineralization, Pathologic / Q000503:physiopathology*; D015519:Bone Density / Q000502:physiology*; D002111:Calcaneus / Q000000981:diagnostic imaging; D002118:Calcium / Q000097:blood; D005260:Female; D050723:Fractures, Bone / Q000503:physiopathology*; D006801:Humans; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D011446:Prospective Studies; D012121:Respiration, Artificial; D012128:Respiratory Distress Syndrome / Q000503:physiopathology*; D012307:Risk Factors; D012709:Serum Albumin
chemical_list: D012709:Serum Albumin; D002118:Calcium