Preexisting Radiographic Damage Linked to Time Since Psoriatic Arthritis Diagnosis

Patients with psoriatic arthritis (PsA) have a substantial prevalence of radiographic damage at baseline, which was associated with time since diagnosis, according to the results of a study published in Arthritis Research & Therapy.

The researchers sought to quantify the prevalence and magnitude of preexisting radiographic damage at baseline; investigate the association between radiographic damage and clinical swollen joint count (SJC) and tender joint count (TJC) prior to treatment with secukinumab; and examine the extent to which radiographic damage at baseline affected the response to secukinumab therapy at weeks 16 and 52.

An in-depth, patient-level and joint-level analysis of pooled data from 2 phase 3 trials of secukinumab (FUTURE 1 and FUTURE 5 (ClinicalTrials.gov Identifiers: NCT01392326 and NCT02404350, respectively) was conducted.

These data included baseline radiographic bone erosion and joint space narrowing (JSN) scores at prespecified locations, according to the van der Heijde–modified total Sharp score (vdH-mTSS) for PsA, as well as SJC and TJC scores.

The association between joint activity (ie, tenderness and swelling) and vdH-mTSS was evaluated at the overall patient and individual joint-level. Treatment response was evaluated using SJC/TJC at week 16 and week 52, as well as the percentage of patients attaining minimal disease activity (MDA) across all assessments within 1 year from FUTURE 5 alone.

Pooled data from 1554 patients with PsA were included in the analysis.

Patients with PsA had substantial erosion and JSN at baseline, with the majority reporting some degree of erosion before their PsA diagnosis. In addition, a larger percentage of patients presented with erosion than with JSN (86% vs 60%, respectively).

Participants with a longer time since PsA diagnosis (5-10 years or 10-50 years) experienced a higher prevalence of radiographic, as evaluated by bone erosion and JSN.

Joint activity was weakly associated with radiographic damage at baseline at the patient-level (Pearson’s coefficients, range, 0.12-0.18), but was strongly associated with radiographic damage at baseline at the individual joint-level, with a higher probability of SJC/TJC associated with higher JSN/erosion scores. All 42 joints analyzed demonstrated statistical significance for the association between joint tenderness and JSN score; all except 1 joints for tenderness and bone erosion scores; and all except 2 joints for swollen and JSN scores, as well as swollen and bone erosion score.

Treatment with secukinumab decreased TJC and SJC across all values of baseline erosion, as well as JSN scores at week 16 and 52. Participants with higher levels of radiographic damage were less likely to achieve 0 tender/0 swollen joint status and had a lower likelihood of attaining MDA.

A key limitation of the study was its cross-sectional design.

The researchers concluded, “Secukinumab therapy, in a dose-dependent manner, was associated with inhibition of joint tenderness and swelling, although high [radiographic damage] at baseline was associated with reduced likelihood of full inhibition.”

Disclosure: Some of the study authors have declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures. 

This article originally appeared on Rheumatology Advisor