Studies on ageing and the severity of radiographic joint damage in rheumatoid arthritis

Arthritis Res Ther. 2015 Aug 24;17(1):222. doi: 10.1186/s13075-015-0740-0.

Abstract

Introduction: The western population is ageing. It is unknown whether age at diagnosis affects the severity of Rheumatoid Arthritis (RA), we therefore performed the present study.

Method: 1,875 RA-patients (7,219 radiographs) included in five European and North-American cohorts (Leiden-EAC, Wichita, Umeå, Groningen and Lund) were studied on associations between age at diagnosis and joint damage severity. In 698 Leiden RA-patients with 7-years follow-up it was explored if symptom duration, anti-citrullinated-peptide-antibodies (ACPA), swollen joint count (SJC) and C-reactive-protein (CRP) mediated the association of age with joint damage. Fifty-six other RA-patients of the EAC-cohort underwent baseline MRIs of wrist, MCP and MTP-joints; MRI-inflammation (RAMRIS-synovitis plus bone marrow edema) was also evaluated in mediation analyses. Linear regression and multivariate normal regression models were used.

Results: Analysis on the five cohorts and the Leiden-EAC separately revealed 1.026-fold and 1.034-fold increase of radiographic joint damage per year increase in age (β=1.026, 1.034, both p<0.001); this effect was present at baseline and persisted over time. Age correlated stronger with baseline erosion-scores compared to joint space narrowing (JSN)-scores (r=0.38 versus 0.29). Symptom duration, ACPA, SJC and CRP did not mediate the association of age with joint damage severity. Age was significantly associated with the MRI-inflammation-score after adjusting for CRP and SJC (β=1.018, p=0.027). The association of age with joint damage (β=1.032, p=0.004) decreased after also including the MRI-inflammation-score (β=1.025, p=0.021), suggesting partial mediation.

Conclusion: RA-patients presenting at higher age have more severe joint damage; this might be partially explained by more severe MRI-detected inflammation at higher age.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Age Factors
  • Aged
  • Aged, 80 and over
  • Aging*
  • Arthritis, Rheumatoid / diagnostic imaging*
  • Arthritis, Rheumatoid / immunology
  • Arthritis, Rheumatoid / pathology*
  • Autoantibodies / analysis
  • Autoantibodies / immunology
  • C-Reactive Protein / analysis
  • Citrulline / immunology
  • Cohort Studies
  • Europe
  • Female
  • Humans
  • Inflammation / diagnostic imaging
  • Inflammation / pathology
  • Joints / pathology*
  • Magnetic Resonance Imaging / methods
  • Male
  • Middle Aged
  • North America
  • Peptides, Cyclic / immunology
  • Radiography
  • Severity of Illness Index

Substances

  • Autoantibodies
  • Peptides, Cyclic
  • Citrulline
  • C-Reactive Protein