title: A close association of body cell mass loss with disease activity and disability in Chinese patients with rheumatoid arthritis.
abstract: OBJECTIVE
  To investigate the association of body cell mass loss with disease activity and disability in rheumatoid arthritis patients.
  
  
  BACKGROUND
  Rheumatoid cachexia, defined as the loss of body cell mass, is important but under-recognized and contributes to morbidity and mortality in patients with rheumatoid arthritis.
  
  
  METHODS
  One hundred forty-nine rheumatoid arthritis patients and 53 healthy, non-rheumatoid arthritis control subjects underwent anthropometric measurements of body mass index and waist and hip circumferences. Bioelectrical impedance analysis was used to determine the subjects' body compositions, including fat mass, skeletal lean mass, and body cell mass. The disease activity of rheumatoid arthritis was assessed using C-reactive protein serum, the erythrocyte sedimentation rate and the 28-joint disease activity score, while disability was evaluated using a health assessment questionnaire.
  
  
  RESULTS
  Rheumatoid arthritis patients had lower waist-to-hip ratio (0.86 ± 0.07 vs. 0.95 ± 0.06; p<0.001) and lower skeletal lean mass indexes (14.44 ± 1.52 vs. 15.18 ± 1.35; p = 0.002) than those in the healthy control group. Compared with rheumatoid arthritis patients with higher body cell masses, those with body cell masses lower than median had higher erythrocyte sedimentation rates (40.10 ± 27.33 vs. 25.09 ± 14.85; p<0.001), higher disease activity scores (5.36 ± 3.79 vs. 4.23 ± 1.21; p = 0.022) and greater disability as measured by health assessment questionnaire scores (1.26 ± 0.79 vs. 0.87 ± 0.79; p = 0.004).
  
  
  CONCLUSIONS
  The loss of body cell mass is associated with higher disease activity and greater disability in rheumatoid arthritis patients. Body composition determined by bioelectrical impedance analysis can provide valuable information for a rheumatologist to more rapidly recognize rheumatoid cachexia in rheumatoid arthritis patients.
authors.affiliation: Division of Allergy, Immunology and Rheumatology, Department of Internal Medicine, Taichung City, Taiwan. blacklark@seed.net.tw
authors.forename: Yi-Ming
authors.initials: YM
authors.lastname: Chen
authors.forename: Hsin-Hua
authors.initials: HH
authors.lastname: Chen
authors.forename: Chia-Wei
authors.initials: CW
authors.lastname: Hsieh
authors.forename: Tsu-Yi
authors.initials: TY
authors.lastname: Hsieh
authors.forename: Joung-Liang
authors.initials: JL
authors.lastname: Lan
authors.forename: Der-Yuan
authors.initials: DY
authors.lastname: Chen
mesh_terms: D000368:Aged; D000886:Anthropometry; D001172:Arthritis, Rheumatoid / Q000503:physiopathology*; D001823:Body Composition / Q000502:physiology*; D015992:Body Mass Index; D016022:Case-Control Studies; D002681:China; D017097:Electric Impedance; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018709:Statistics, Nonparametric; D011795:Surveys and Questionnaires; D055105:Waist Circumference; D049629:Waist-Hip Ratio; D015431:Weight Loss / Q000502:physiology*