Differences in the response to TNF inhibitors at distinct joint locations in patients with psoriatic arthritis: results from nine European registries.

Background: Efficacy of tumour necrosis factor inhibitors (TNFi) for peripheral arthritis in patients with psoriatic arthritis (PsA) has been established in randomized clinical trials that have used improvement in summated joint counts as an outcome. Whether joints at different anatomical locations might respond differentially to TNFi remains unknown. The aim of the study was to investigate potential variations in the responsiveness to a first tumour necrosis factor inhibitor (TNFi) among joints at distinct locations in patients with psoriatic arthritis (PsA) treated in routine clinical care.
Methods: Bionaive PsA patients from nine European countries were included in this observational cohort study if ≥ 1 joint was swollen at the initiation of a first TNFi as monotherapy or added to methotrexate. Only the 28-joint count was available without imaging data confirming the presence of synovitis. The primary outcome was time to first resolution of joint swelling at each joint level. Hazard ratios (HR) for resolution comparing different joint locations were estimated using interval-censored mixed-effects Cox proportional hazards models, including a random effect for country and patient, adjusted for age and sex.
Results: A total of 1729 patients with 8397 swollen joints at the start of TNFi were included. Considering the upper extremity, a higher rate of resolution of joint swelling (HR, 95% CI) was observed for the shoulder (1.65, 1.16-2.35) and elbow (1.90, 1.38-2.61), while a lower rate was found for the wrist (0.72, 0.62-0.83) compared to the joints of digit 3. Within fingers, and using the same reference, joint swelling resolved fastest in digit 4 (1.77, 1.49-2.11) and digit 5 (1.88, 1.53-2.31). A lower rate of resolution of joint swelling was found for the knee in comparison to the elbow, the corresponding joint on the upper limb (0.56, 0.40-0.78).
Conclusion: The time to resolution of joint swelling upon treatment with TNFi in patients with PsA seems to depend on the localisation of the affected joints.
Competing Interests: Declarations. Ethics approval and consent to participate: The study was approved by the respective national data protection agencies and research ethical committees according to legal regulatory requirements in the participating countries (online supplemental table S6). Consent for publication: Not required. Competing interests: AG reports a grant from Novartis (paid to employer). AGL reports a research grant from Novartis; speaking and/or consulting fees from Abbvie, Janssen, Eli Lilly, MSD, Novartis, Pfizer, and UCB; and being a paid instructor for Pfizer. BeG reports a grant from Novartis (paid to institution); grants from Abbvie, BMS, and Sandoz paid to the institution, outside the submitted work. BrM reports a research grant from Novartis paid to the employer (outside the submitted work); speaker fees from Novartis; grants from the Research Council of Norway to the Centre for treatment of Rheumatic and Musculoskeletal Diseases (REMEDY). CC reports speaking and consulting fees from Abbvie, Amgen, Boehringer-Ingelheim, Ewopharma, Eli Lilly, Novartis, and Pfizer. FI reports a provision from Abbvie for article processing; consulting fees from Abbvie, Janssen, and UCB; payments or honoraria from Abbvie, Eli Lilly, Galapagos, Janssen, and UCB; support for attending meetings from Abbvie, Astra-Zeneca, Eli Lilly, Galapagos, Janssen, and UCB. GTJ reports a research grant from Amgen paid to the employer; speaker fees from Janssen. IC reports speaker and/or consulting fees form BMS, Eli Lilly, Galapagos, Gilead, Janssen, Novartis, MSD, Pfizer, and GSK. IvdHB reports payment for lecture from UCB and support for attending a meeting from Pfizer. JMD reports grants from the Portuguese Society of Rheumatology (RheumaPlus grant); consulting fees from Abbvie, Bial, Merck Sharp & Dohme, and Pfizer; payments or honoraria from Abbvie, Bial, Merck Sharp & Dohme, Novartis, Pfizer, and UCB; JKW reports speaking fees from Abbvie, and Amgen (paid to institution); research support from Abbvie, Amgen, Eli Lilly, Novartis, and Pfizer (unrelated to the present study and paid to institution); he acts as co-chair of the Swedish Society for Rheumatology’s working group which is annually updating the Swedish treatment recommendations for axial spondyloarthritis and psoriatic arthritis. JZ reports speaking fees from Abbvie, Akord, Astra Zeneca, Celltrion, Eli Lilly, Pfizer, and Sobi; consulting fees from Abbvie, and Astra Zeneca; support for attending meetings from Abbvie, and Pfizer; participation in advisory boards for Abbvie, and Astra Zeneca. KP reports consulting fees from Abbvie, UCB, Pfizer, Eli Lilly, Celltrion, MSD, and Novartis. LMØ reports a research grant from Novartis paid to the employer. MJN reports a research grant from Novartis paid to the institution; consulting fees from Abbvie, Amgen, Eli Lilly, Janssen, Novartis, and Pfizer paid to the institution; speaking fees from Abbvie, Amgen, Eli Lilly, Janssen, Novartis, and Pfizer paid to the institution; support for attending meetings from Janssen and UCB; participation in advisory boards from Eli Lilly, Janssen, Novartis and Pfizer paid to the institution; he is a scientific member of the SCQM registry and of the EuroSpA collaboration and an ASAS-EULAR taskforce member. MØ reports grants from Abbvie, Amgen, BMS, Celgene, Eli Lilly, Merck, Novartis, and UCB, outside the submitted work; consulting fees from Abbvie, BMS, Eli Lilly, Galapagos, Gilead, Janssen, Merck, Novatis, Pfizer, and UCB; payments or honoraria from Abbvie, BMS, Eli Lilly, Galapagos, Gilead, Janssen, Merck, Novartis, Pifzer, and UCB. MLH reports consulting fees from Abbvie paid to institution; research grants from Abbvie, BMS, Eli Lilly, Lundbeck Fondation, MSD, Pfizer, Sandoz, Novartis, and Nordforsk, all paid to institution; speaking fees from Pfizer, Medac, Sandoz paid to the institution and a personal honorarium from Novartis; participation in an advisory board of Abbvie paid to the institution; being the previous chair of the steering committee of the Danish Rheumatology Quality Registers, which receive public funding from the hospital owners and from pharmaceutical companies; she co-chairs EuroSpA, which generates real-world evidence of treatment of psoriatic arthritis and axial spondyloarthritis based on secondary data and is partly funded by Novartis. MS reports consulting fees from Janssen-Cilag, Boehringer-Ingelheim, and Pfizer; payments or honoraria from BMS, Boehringer-Ingelheim, and GSK. RM reports payments or honoraria from Abbvie, Amgen, Eli Lilly, and Janssen Biotech. RP reports consulting fees from Boehringer Ingelheim and Celltrion, speaking fees from Boehringer Ingelheim, Eli Lilly, Janssen, and UCB; participation in advisory boards for Boehringer Ingelheim, Eli Lilly, and UCB. SHR reports a research grant from Novartis. SK reports a grant from Novartis (paid to employer). VR reports personal grants for the expenses of the research group from the competitive State Research Financing of the Expert Responsibility Area of Kanta-Häme Central Hospital and of Tampere University Hospital, as well as from the Wilhelm and Else Stockmann’s Foundation; payments or honoraria from Abbvie, Novartis, and Viatris. ZR reports payment or honoraria from Abbvie, Amgen, AstraZeneca, Boehringer, Biogen, Eli Lilly, Janssen, Medis, MSD, Novartis, Pfizer, Roche, and Sandoz Lek; payments for expert testimony from Abbvie, Amgen, AstraZeneca, Boehringer, Biogen, Eli Lilly, Janssen, Medis, MSD, Novartis, Pfizer, Roche, and Sandoz Lek; being president of the section of rheumatology of the Slovenian Medical Association. AC, AS, BM, BT, BjG, BuM, CM, CO, GJM, OD, OP, PV, and RB declare they have no conflicts of interests.
(© 2025. The Author(s).)