Background Psoriatic arthritis (PsA) is an inflammatory spondyloarthritis associated with psoriasis. Over the recent years the treatment of PsA has changed dramatically with the use of synthetic (s) disease modified anti-rheumatic drugs (DMARDs) as well as biologic (b) DMARDs, particularly tumor necrosis factor inhibitors. The goal of all these therapies is to achieve remission or minimal disease activity (MDA) . Once remission is achieved and sustained the question is whether the treatment should be continued at full dosage, at a tapered dosage or should be discontinued. For PsA there are no recommendations for dosage tapering or discontinuation of biologic therapy and literature data regarding maintained clinical remission is conflicting.
B-mode (BM) musculoskeletal (MS) ultrasound (US) has been widely shown to be more sensitive than clinical assessment in detecting joint synovitis and enthesitis [2,3] and Doppler technique is able to identify inflammatory activity [3,4].
Objectives To describe and compare clinical and MSUS features between PsA patients treated with full and tapered dosage of bDMARDs. The secondary objective was to compare clinical and MSUS features between PsA patients treated with bDMARDs with and without concomitant sDMARDs.
Methods We evaluated 102 patients with PsA treated with bDMARDs. The bDMARD dosage tapering had been made in patients with a maintained remission or MDA according to their attending rheumatologist and with the patient acceptance. The bDMARDs tapering consisted of the followings: increase the interval between doses for subcutaneous bDMARDs or reduction of the dose for intravenous bDMARDs. The clinical evaluation consisted of a dermatologic and rheumatologic assessment of disease activity. The presence of BM and colour Doppler (CD) synovitis, tenosynovitis, enthesopathy and paratenonitis was investigated by a rheumatologist blinded to drug dosage, clinical assessments and laboratory results.
Results Seventy four (72.5%) patients received full dosage of bDMARDs and 28 (27.5%) received tapered dosage. The duration with biologic therapy and with current biologic therapy were significantly higher in patients with tapered dosages (p=0.008 and p=0.001, respectively). We found no significant differences between clinical, laboratory and US variables, both for BM and CD between patients with full and tapered dosage and between patients with and without concomitant sDMARD.
Conclusions Clinical assessment, MSUS variables, and MDA status are similar in patients receiving full and tapered dosage of bDMARDs.
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Disclosure of Interest None declared