Background TNFi drug survival is one of the valid outcome measure in rheumatological diseases. Patients with psoriatic arthritis (PsA) usually have both joint/back pain diseases and skin disorders. Thus, efficacy of TNFi may be related with joint and skin disease. In fact, PsA patients have different way from ankylosing spondylitis.
Objectives Objective of this study was to compare TNFi drug survival in PsA and ankylosing spondylitis (AS).
Methods HÜR-BİO (Hacettepe University Rheumatology Biologic Registry) is a single center biological registry since 2005 in Turkey. Data collected includes demographic data, co-morbidities, smoking, switch ratio, baseline and follow-up disease activity parameters (such as BASDAI, BASFI, CRP, ESR, global VAS, swollen joint count ad tender joint count). If patients took TNFi drugs last 6 months, patient accepted as ongoing TNFi treatment. Kaplan-Meier plots and log rank tests were used to assess drug survival.
Results There were 630 AS and 119 PsA [30 (25.2%) psoriatic spondylitis] patients with TNFi in this database. Mean age in PsA and AS were 45±11 vs 41±11 years (p=0.005). Mean disease duration in PsA and AS were 7.1±5.6 vs 9.7±7.2 years (p<0.001). AS patients were more frequently male 415/630 (65.8%) vs 34/119 (28.6%), p<0.001. Mean TNFi duration was similar in PsA and AS patients 29±29 vs 34±31 months, p>0.05. TNFi drugs in PsA and AS patients were adalimumab (36.1% vs 23.1%), etanercept (27.7% vs 38.1%), infliximab (26.9% vs 34.4.%) and golimumab (8.4% vs 4.1%), p<0.001. PsA patients were used more frequetly DMARDs than AS patients [methotrexate 48.2% vs 6.9%, p<0.001, leflunomide 20.1% vs 0.9%, p<0.001, sulphasalazine 14.0% vs 25.4%, p>0.05]. Patients with PsA had higher TNFi switch rate than AS patients 45/116 (38.8%) vs 154/578 (26.6%), p=0.008. Baseline ESR 30±26 vs 33±23 mm/hour, CRP 2.39±3.27 vs 3.70±7.24 mg/dl, BASDAI score 5.6±2.0 vs 5.6±1.8 and BASFI score 4.2±2.9 vs 4.4±2.6 were similar in PsA and AS patients. However, tender joint counts 5.2±5.4 vs 0.29±0.96, p<0.001 and swollen joit counts 2.54±2.73 vs 0.58±0.27 p<0.001 were higher in PsA patients. Patients with PsA had better drug survival than AS patients (log rank 0.012) (Fig. 1).
Conclusions TNFi drug survival is better in PsA than AS patients. Distribution of TNFi and DMARDs, switch rates may be responsible from those results. However, we thought that, improvement of peripheral arthritis and skin lesions are also reflect good TNFi survival in PsA.
Disclosure of Interest None declared