title: An Increased Serum N-Terminal Telopeptide of Type I Collagen, a Biochemical Marker of Increased Bone Resorption, Is Associated with Infliximab Therapy in Patients with Crohn's Disease.
abstract: BACKGROUND
  Osteopenia and osteoporosis are considered to be extra-intestinal manifestations of inflammatory bowel disease (IBD). Anti-tumor necrosis factor (TNF)-α biologics have been introduced as novel medications for an active IBD. However, it is still not well documented whether anti-TNF-α affects the frequency of bone loss or abnormality of bone mineral markers among patients with IBD.
  
  
  OBJECTIVE
  This study was to investigate the biochemical basis of low bone mineral density (BMD) and increased turnover in IBD during infliximab (IFX) therapy.
  
  
  METHODS
  Forty patients with Crohn's disease (CD), 80 patients with ulcerative colitis (UC), and 65 age- and gender-matched controls were included. BMD was measured with dual-energy X-ray absorptiometry, and vitamins K and D were measured as serum undercarboxylated osteocalcin (ucOC) and 1,25-(OH)2D, respectively. Bone formation and resorption were based on measuring bone-specific alkaline phosphatase (BAP) and serum N-terminal telopeptide of type I collagen (NTx), respectively.
  
  
  RESULTS
  Significantly lower BMD was found in patients with UC and CD as compared to controls (P < 0.05). BAP, 1,25-(OH)2D, ucOC, and NTx were significantly higher in CD patients, but not in UC patients as compared to controls (P < 0.05). Further, serum NTx level was significantly higher in CD patients who were receiving IFX as compared to CD patients who were not receiving IFX (P < 0.01).
  
  
  CONCLUSIONS
  A lower BMD and higher bone metabolism markers were found in CD patients as compared to controls or UC patients. A significant increased serum level of NTx, a biochemical marker of increased bone resorption, was observed in CD patients during IFX therapy.
authors.affiliation: First Department of Medicine, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, 431-3192, Japan. sugimken@hama-med.ac.jp.
authors.forename: Ken
authors.initials: K
authors.lastname: Sugimoto
authors.affiliation: Centre for Gastroenterology and Inflammatory Bowel Disease Research, Hamamatsu South Hospital, Hamamatsu, 430-0846, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Ikeya
authors.affiliation: Centre for Gastroenterology and Inflammatory Bowel Disease Research, Hamamatsu South Hospital, Hamamatsu, 430-0846, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Iida
authors.affiliation: Centre for Gastroenterology and Inflammatory Bowel Disease Research, Hamamatsu South Hospital, Hamamatsu, 430-0846, Japan.
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Kawasaki
authors.affiliation: Centre for Gastroenterology and Inflammatory Bowel Disease Research, Hamamatsu South Hospital, Hamamatsu, 430-0846, Japan.
authors.forename: Osamu
authors.initials: O
authors.lastname: Arai
authors.affiliation: Orthopedics Unit, Hamamatsu South Hospital, Hamamatsu, 430-0846, Japan.
authors.forename: Keita
authors.initials: K
authors.lastname: Umehara
authors.affiliation: Centre for Gastroenterology and Inflammatory Bowel Disease Research, Hamamatsu South Hospital, Hamamatsu, 430-0846, Japan.
authors.forename: Fumitoshi
authors.initials: F
authors.lastname: Watanabe
authors.affiliation: First Department of Medicine, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, 431-3192, Japan.
authors.forename: Shinya
authors.initials: S
authors.lastname: Tani
authors.affiliation: First Department of Medicine, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, 431-3192, Japan.
authors.forename: Shinji
authors.initials: S
authors.lastname: Oishi
authors.affiliation: Department of Endoscopic and Photodynamic Medicine, Hamamatsu University School of Medicine, Hamamatsu, 431-3192, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Osawa
authors.affiliation: Inflammatory Bowel Disease Centre, Yokkaichi Hazu Medical Centre, Mie, 510-0016, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Yamamoto
authors.affiliation: Centre for Gastroenterology and Inflammatory Bowel Disease Research, Hamamatsu South Hospital, Hamamatsu, 430-0846, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Hanai
mesh_terms: D015502:Absorptiometry, Photon; D000328:Adult; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use*; D015415:Biomarkers / Q000097:blood; D015519:Bone Density / Q000187:drug effects; D001862:Bone Resorption / Q000097:blood*; D001842:Bone and Bones / Q000000981:diagnostic imaging / Q000187:drug effects* / Q000378:metabolism; D016022:Case-Control Studies; D003093:Colitis, Ulcerative / Q000150:complications / Q000175:diagnosis / Q000188:drug therapy*; D024042:Collagen Type I / Q000097:blood*; D003424:Crohn Disease / Q000097:blood / Q000175:diagnosis / Q000188:drug therapy*; D005260:Female; D005765:Gastrointestinal Agents / Q000627:therapeutic use*; D006801:Humans; D000069285:Infliximab / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D010012:Osteogenesis / Q000187:drug effects; D010455:Peptides / Q000097:blood*; D011446:Prospective Studies; D013997:Time Factors; D016896:Treatment Outcome; D015854:Up-Regulation
chemical_list: D000893:Anti-Inflammatory Agents; D015415:Biomarkers; D024042:Collagen Type I; D005765:Gastrointestinal Agents; D010455:Peptides; C052929:collagen type I trimeric cross-linked peptide; D000069285:Infliximab
keywords: Bone mineral density; Bone resorption; Inflammatory bowel disease; Infliximab; Osteoporosis