Ann Rheum Dis 65:895-898 doi:10.1136/ard.2005.043158
  • Extended report

Baseline comorbidity levels in biologic and standard DMARD treated patients with rheumatoid arthritis: results from a national patient register

  1. K Hyrich1,
  2. D Symmons1,
  3. K Watson1,
  4. A Silman1,
  5. BSRBR Control Centre Consortium,
  6. on behalf of the British Society for Rheumatology Biologics Register2,*
  1. 1Arthritis Research Campaign Epidemiology Unit, University of Manchester, Manchester M13 9PT, UK
  2. 2Members of BSRBR Control Centre Consortium (see the appendix)
  1. Correspondence to:
    Professor A Silman
    ARC Unit, University of Manchester, Manchester, UK; a.silman{at}
  • Accepted 4 November 2005
  • Published Online First 8 December 2005


Objective: To describe the occurrence of baseline comorbidity in subjects with active rheumatoid arthritis starting treatment with biological agents. Such data are necessary to interpret the reported occurrence of adverse events following treatment.

Methods: Baseline comorbidity was recorded in a large national cohort of patients with rheumatoid arthritis newly starting biological agents. The distribution of the number and types of comorbidities is presented.

Results: In all, 7818 patients treated with biological agents (infliximab 3332, etanercept 3302, adalimumab 1059, anakinra 132) were included in the analysis. Comorbidity was common, with 58% of patients having at least one comorbid condition and 25% having more than one. The most frequent comorbid conditions were hypertension, depression, peptic ulcer disease, and respiratory disease.

Conclusions: In routine use, patients treated with biological agents have high levels of baseline comorbidity, which should influence the interpretation of reported adverse events.


  • Published Online First 8 December 2005

  • * The members of the BSRBR Control Centre Consortium are given in the appendix.