title: Increase of hemoglobin levels by anti-IL-6 receptor antibody (tocilizumab) in rheumatoid arthritis.
abstract: OBJECTIVE
  To compare the effect of tocilizumab (TCZ) with other biologic therapies in improving anemia of rheumatoid arthritis (RA) patients.
  
  
  METHODS
  We compared the change of hemoglobin (Hb) levels in a cohort of 147 consecutive RA patients who were treated with biologics for more than 12 weeks. Twenty eight patients were treated with TCZ, and 119 patients were treated with biologics other than TCZ (87 with TNF inhibitors and 32 with abatacept). The change of Hb levels from baseline to week 12 was compared between the TCZ and the non-TCZ groups. We performed univariate and multivariate analyses with adjustment of potential confounders such as baseline characteristics, concomitant treatment, and the clinical response to treatment.
  
  
  RESULTS
  Hb levels generally increased after biologic therapies both in the TCZ and the non-TCZ groups. The increase of Hb levels was greater in the TCZ group than in the non-TCZ groups (1.1 g/dL in the TCZ group vs 0.3 g/dL in the non-TCZ group, p = 0.009). Univariate analysis revealed that increase of Hb levels was also significantly associated with lower Hb, higher Low Hemoglobin Density, and higher CRP levels at baseline and greater reduction in the clinical disease activity index. TCZ therapy was significantly associated with the increase of Hb levels even after adjustment for these factors by multivariate analysis (p<0.001, effect size 0.08-0.12).
  
  
  CONCLUSIONS
  TCZ therapy is an independent factor associated with the increase of Hb level after biologic therapies in RA patients. It will help in selecting appropriate biologics for RA patients with anemia.
authors.affiliation: Department of the Control for Rheumatic Diseases, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Motomu
authors.initials: M
authors.lastname: Hashimoto
authors.affiliation: Department of the Control for Rheumatic Diseases, Graduate School of Medicine, Kyoto University, Kyoto, Japan; Department of Rheumatology and Clinical Immunology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Takao
authors.initials: T
authors.lastname: Fujii
authors.affiliation: Department of Experimental Immunology, Immunology Frontier Research Center, Osaka University, Osaka, Japan.
authors.forename: Masahide
authors.initials: M
authors.lastname: Hamaguchi
authors.affiliation: Department of the Control for Rheumatic Diseases, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Moritoshi
authors.initials: M
authors.lastname: Furu
authors.affiliation: Department of the Control for Rheumatic Diseases, Graduate School of Medicine, Kyoto University, Kyoto, Japan; Department of Orthopedic Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Hiromu
authors.initials: H
authors.lastname: Ito
authors.affiliation: Center for Genomic Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Chikashi
authors.initials: C
authors.lastname: Terao
authors.affiliation: Division of Clinical and Epidemiological Database, Department of Information Governance, National Cerebral and Cardiovascular Center, Osaka, Japan.
authors.forename: Keiichi
authors.initials: K
authors.lastname: Yamamoto
authors.affiliation: Department of the Control for Rheumatic Diseases, Graduate School of Medicine, Kyoto University, Kyoto, Japan; Department of Health Information Management, Kurashiki Sweet Hospital, Kurashiki, Japan.
authors.forename: Wataru
authors.initials: W
authors.lastname: Yamamoto
authors.affiliation: Department of Rheumatology and Clinical Immunology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Matsuo
authors.affiliation: Department of Rheumatology and Clinical Immunology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Masato
authors.initials: M
authors.lastname: Mori
authors.affiliation: Department of Rheumatology and Clinical Immunology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Koichiro
authors.initials: K
authors.lastname: Ohmura
authors.affiliation: Department of Hematology and Oncology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kawabata
authors.affiliation: Department of Rheumatology and Clinical Immunology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Tsuneyo
authors.initials: T
authors.lastname: Mimori
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000740:Anemia / Q000150:complications / Q000628:therapy; D061067:Antibodies, Monoclonal, Humanized / Q000276:immunology* / Q000627:therapeutic use*; D001172:Arthritis, Rheumatoid / Q000097:blood* / Q000150:complications / Q000276:immunology / Q000628:therapy*; D015331:Cohort Studies; D005260:Female; D006454:Hemoglobins / Q000378:metabolism*; D006801:Humans; D007167:Immunotherapy; D008297:Male; D008875:Middle Aged; D019947:Receptors, Interleukin-6 / Q000276:immunology*; D055815:Young Adult
chemical_list: D061067:Antibodies, Monoclonal, Humanized; D006454:Hemoglobins; D019947:Receptors, Interleukin-6; C502936:tocilizumab