Disconnect between inflammation and joint destruction after treatment with etanercept plus methotrexate: results from the trial of etanercept and methotrexate with radiographic and patient outcomes.
OBJECTIVE
To determine the relationship between disease activity and radiographic progression of joint destruction in patients with rheumatoid arthritis (RA) treated with methotrexate (MTX), those treated with etanercept, and those treated with the combination of MTX plus etanercept.


METHODS
Baseline, 12-month, and 24-month data from the Trial of Etanercept and Methotrexate with Radiographic and Patient Outcomes database were analyzed. The dependent variable was the 1-year change in the modified Sharp/van der Heijde score (Sharp score); therefore, 2 interval changes per patient were available. Interval change in the Sharp score was modeled by time (years), treatment, disease activity, and the interaction (disease activity x treatment). Disease activity was reflected by the time-averaged Disease Activity Score (taDAS) and the time-averaged C-reactive protein (taCRP) level, which were calculated per 1-year interval. Generalized mixed linear modeling (GMLM) was used to adjust for within-patient correlation.


RESULTS
GMLM confirmed a significant interaction between treatment and the taCRP level and taDAS with respect to the change in Sharp score (P = 0.012 and P = 0.03, respectively). In patients treated with MTX alone, radiographic progression increased with an increasing taCRP level or taDAS, although progression rates were low in patients whose disease was in remission and in those with low-to-moderate disease activity. This relationship was less clear in patients treated with etanercept and was absent in those who received combination therapy.


CONCLUSIONS
Combination therapy with MTX plus etanercept uncouples the classic relationship between disease activity and radiographic progression in patients with RA.
Landewé
Robert
R
University Hospital Maastricht, Maastricht, The Netherlands. rlan@sint.azm.nl
van der Heijde
Désirée
D
Klareskog
Lars
L
van Vollenhoven
Ronald
R
Fatenejad
Saeed
S
D018501:Antirheumatic Agents / Q000627:therapeutic use*; D001172:Arthritis, Rheumatoid / Q000097:blood / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000473:pathology*; D002097:C-Reactive Protein / Q000032:analysis; D004185:Disability Evaluation; D018450:Disease Progression; D004359:Drug Therapy, Combination; D000068800:Etanercept; D006801:Humans; D007074:Immunoglobulin G / Q000627:therapeutic use*; D007249:Inflammation / Q000097:blood / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000473:pathology*; D007596:Joints / Q000473:pathology / Q000503:physiopathology; D008727:Methotrexate / Q000627:therapeutic use*; D011859:Radiography; D018124:Receptors, Tumor Necrosis Factor / Q000627:therapeutic use*; D012189:Retrospective Studies; D012720:Severity of Illness Index; D016896:Treatment Outcome; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors
D018501:Antirheumatic Agents; D007074:Immunoglobulin G; D018124:Receptors, Tumor Necrosis Factor; D014409:Tumor Necrosis Factor-alpha; D002097:C-Reactive Protein; D000068800:Etanercept; D008727:Methotrexate