Bone anabolic changes progress in psoriatic arthritis patients despite treatment with methotrexate or tumour necrosis factor inhibitors.
OBJECTIVE
To investigate whether methotrexate or tumour necrosis factor inhibitors (TNFi) affect osteophyte formation in patients with psoriatic arthritis (PsA).


METHODS
41 patients with PsA were examined for the presence of osteophytes and erosions at the metacarpophalangeal joints by high-resolution micro-CT imaging. The size of each individual lesion was quantified at baseline and 1-year follow-up in PsA patients treated with TNFi (N=28) or methotrexate (N=13). Groups were comparable for age, sex, disease duration and activity and baseline burden of osteophytes.


RESULTS
In total, 415 osteophytes (TNFi N=284, methotrexate N=131) were detected. Osteophyte size increased significantly from baseline to follow-up in the TNFi group (mean±SEM change +0.23±0.02 mm; p<0.0001) and the methotrexate group (+0.27±0.03 mm, p<0.0001). In both treatment groups, the majority of osteophytes showed progression (TNFi 54.3%, methotrexate 61.1%), whereas regression of lesions was rare (less than 10%). In contrast to osteophytes, clinical disease activity decreased in both groups of PsA patients and erosions showed an arrest of progression in both groups.


CONCLUSIONS
Osteophytes progress in PsA patients treated with either methotrexate or TNFi. These data provide the first evidence that pathological bone formation in the appendicular skeleton of patients with PsA is not affected by current antirheumatic treatment strategies.
Department of Internal Medicine 3, University of Erlangen-Nuremberg, Erlangen, Germany.
Stephanie
S
Finzel
Sebastian
S
Kraus
Sarah
S
Schmidt
Axel
A
Hueber
Juergen
J
Rech
Klaus
K
Engelke
Matthias
M
Englbrecht
Georg
G
Schett
D000068879:Adalimumab; D000328:Adult; D000368:Aged; D000911:Antibodies, Monoclonal / Q000627:therapeutic use; D061067:Antibodies, Monoclonal, Humanized / Q000627:therapeutic use; D018501:Antirheumatic Agents / Q000627:therapeutic use*; D015535:Arthritis, Psoriatic / Q000000981:diagnostic imaging / Q000188:drug therapy*; D015331:Cohort Studies; D018450:Disease Progression; D000068800:Etanercept; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000627:therapeutic use; D000069285:Infliximab; D008297:Male; D008662:Metacarpophalangeal Joint / Q000000981:diagnostic imaging*; D008727:Methotrexate / Q000627:therapeutic use*; D008875:Middle Aged; D054850:Osteophyte / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000517:prevention & control; D018124:Receptors, Tumor Necrosis Factor / Q000627:therapeutic use; D016896:Treatment Outcome; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors*; D055114:X-Ray Microtomography
D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D018501:Antirheumatic Agents; D007074:Immunoglobulin G; D018124:Receptors, Tumor Necrosis Factor; D014409:Tumor Necrosis Factor-alpha; D000069285:Infliximab; D000068879:Adalimumab; D000068800:Etanercept; D008727:Methotrexate