title: Osteoporosis in rheumatoid arthritis. A monozygotic co-twin control study.
abstract: OBJECTIVE
  To quantify the magnitude and distribution of osteoporosis in rheumatoid arthritis (RA).
  
  
  METHODS
  Bone mineral density (BMD) was measured by dual x-ray absorptiometry, in a monozygotic co-twin control study.
  
  
  RESULTS
  BMD was reduced at most skeletal sites in the twin with RA compared with the co-twin (lumbar spine 4.6%, femoral neck 9.7%, total body 5.7%). Differences in lean soft tissue (5.6% for total body) correlated with differences in BMD between twins at multiple sites.
  
  
  CONCLUSIONS
  Osteoporosis in RA is generalized and may be related to loss of mobility or muscle mass associated with the disease.
authors.affiliation: Garvan Institute of Medical Research, St. Vincent's Hospital, Sydney, Australia.
authors.forename: P N
authors.initials: PN
authors.lastname: Sambrook
authors.forename: T D
authors.initials: TD
authors.lastname: Spector
authors.forename: E
authors.initials: E
authors.lastname: Seeman
authors.forename: N
authors.initials: N
authors.lastname: Bellamy
authors.forename: R R
authors.initials: RR
authors.lastname: Buchanan
authors.forename: D L
authors.initials: DL
authors.lastname: Duffy
authors.forename: N G
authors.initials: NG
authors.lastname: Martin
authors.forename: R
authors.initials: R
authors.lastname: Prince
authors.forename: E
authors.initials: E
authors.lastname: Owen
authors.forename: A J
authors.initials: AJ
authors.lastname: Silman
mesh_terms: D001172:Arthritis, Rheumatoid / Q000150:complications / Q000453:epidemiology* / Q000235:genetics; D015519:Bone Density / Q000502:physiology; D004200:Diseases in Twins / Q000453:epidemiology* / Q000235:genetics; D005260:Female; D005272:Femur Neck / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D008159:Lumbar Vertebrae / Q000473:pathology / Q000503:physiopathology; D008297:Male; D010024:Osteoporosis / Q000150:complications / Q000453:epidemiology* / Q000235:genetics; D012042:Registries; D012044:Regression Analysis; D011795:Surveys and Questionnaires; D014430:Twins, Monozygotic; D006113:United Kingdom / Q000453:epidemiology