title: Hand bone mineral density is associated with both total hip and lumbar spine bone mineral density in post-menopausal women with RA.
abstract: OBJECTIVE
  RA is associated with localized bone loss in the hands, as well as generalized osteoporosis. We evaluated the relationship between hand digital X-ray radiogrammetry BMD (DXR-BMD) and total hip and lumbar spine BMD.
  
  
  METHODS
  We conducted a cross-sectional study of 138 post-menopausal women with RA. The DXR-BMD was calculated based on digitized hand radiographs. Measurements of the total hip and lumbar spine BMD were performed by a DXA-BMD (BMDa) scan. Patient and physician questionnaires and laboratory samples supplied information on relevant covariates. Separate multivariate linear regression models were constructed to determine the cross-sectional relationship between hand DXR-BMD (independent variable) and total hip or lumbar spine BMD (dependent variables).
  
  
  RESULTS
  The cohort comprised women with a median age of 61 years and RA disease duration of 13 years. Seventy-six per cent were either RF and/or anti-cyclic citrullinated peptide (anti-CCP) positive and most had moderate disease activity [median disease activity score-28 joint count (DAS28) 3.7]. Hand DXR-BMD was significantly associated with total hip BMD (beta = 0.61; P < 0.0001) and lumbar spine BMD (beta = 0.62; P < 0.0008) in adjusted models.
  
  
  CONCLUSIONS
  This study suggests that hand DXR-BMD is associated with both the total hip and lumbar spine BMD among post-menopausal women with RA. The relationship between bone loss in the hands and generalized osteoporosis should be further explored in longitudinal studies of patients with RA.
authors.affiliation: Brigham and Women's Hospital, PBB-B3, Boston, MA 02115, USA. sdesai5@partners.org
authors.forename: Sonali P
authors.initials: SP
authors.lastname: Desai
authors.forename: Ellen M
authors.initials: EM
authors.lastname: Gravallese
authors.forename: Nancy A
authors.initials: NA
authors.lastname: Shadick
authors.forename: Roberta
authors.initials: R
authors.lastname: Glass
authors.forename: Jing
authors.initials: J
authors.lastname: Cui
authors.forename: Michelle
authors.initials: M
authors.lastname: Frits
authors.forename: Lori B
authors.initials: LB
authors.lastname: Chibnik
authors.forename: Nancy
authors.initials: N
authors.lastname: Maher
authors.forename: Michael E
authors.initials: ME
authors.lastname: Weinblatt
authors.forename: Daniel H
authors.initials: DH
authors.lastname: Solomon
mesh_terms: D015502:Absorptiometry, Photon; D000367:Age Factors; D000368:Aged; D001172:Arthritis, Rheumatoid / Q000503:physiopathology*; D015519:Bone Density / Q000502:physiology*; D003430:Cross-Sectional Studies; D004812:Epidemiologic Methods; D005260:Female; D006621:Hip Joint / Q000503:physiopathology; D006801:Humans; D008159:Lumbar Vertebrae / Q000503:physiopathology; D050279:Metacarpal Bones / Q000503:physiopathology*; D008875:Middle Aged; D017698:Postmenopause / Q000502:physiology; D013997:Time Factors