Background:Limited data are available regarding the burden of nail disease in psoriatic arthritis (PsA). The latest data show that nail involvement in PsA patients (pts) is associated with significantly more severe disease status (1).Objectives:To analyze, in clinical practice, the association of nail psoriasis with disease activity, quality of life, and work productivity in PsA pts.Methods:588 pts (M/F–277 /311) with PsA according to CASPAR criteria were included in the study. Data were collected from 43 rheumatology clinics from different regions of the Russian Federation. Pts’ age 48.6±0.5 years (yrs), disease duration 7.0±0.3 yrs. Pts underwent standard clinical examination of PsA activity. Pts were split into two groups (gr.): those with nail psoriasis – gr.1, and those without it – gr.2. Demographics, disease activity, quality of life, and work productivity were compared between pts with and without nail psoriasis using Pearson’s chi-square test and Mann–Whitney U test.Results:Gr.1 includes 312 (53.1%) cases, gr.2 – 276 (46.9%) cases. More pts in gr.1 were males (51.9% vs 44.1%, р=0.013), disabled at work (37.20% vs 26.40%, р=0.000), chronic smokers (18.9% vs 8.7%, р=0.000) and with axial PsA disease signs according to physician (35.0% vs 26.4%, р=0.025) compared to pts in gr.2. Pts in gr.1 had higher tender and swollen joint counts: 8 [4-15] vs 5 [2-12] (р=0.002) and 5 [1-9] vs 2 [0-7] (р=0.003) respectively. Gr.1 pts had higher disease activity measured by DAPSA 25 [15-39] vs 20 [12-33] (p= 0.001), higher frequency of dactylitis (24.4% vs 16.7% р=0.022) and heel enthesitis (17.0% vs 10.1% р=0.016) respectively, higher frequency of erosive radiographic arthritis of feet (45.0% vs 31.2% р=0.003) compared to gr.2 pts. Pts in gr.1 had worse skin psoriasis measured by Psoriasis Area Severity Index – 6 [2-14] vs 3 [1-6] (р=0.000). Less pts in gr.1 than in gr.2 (27.0% vs 52.0% р=0.004) achieved minimal disease activity (MDA). Pts’ reported outcomes (PRO’s) in gr.1 were worse than in gr.2 in regard to reduced health-related quality of life according to PsAID (4.9±2.3 vs 4.0±2.3, р=0.040) and to EQ-5D (0.56±0.19 vs 0.64 ±0.21, р=0.024) questionnaires, overall work impairment (0.0 [0.0-0.3] vs 0.0 [0.0-0.2], р=0.034) and overall activity impairment (0.4 [0.1-0.7] vs 0.3 [0.0-0.5], р=0.006) according to WPAI.Conclusion:Nail involvement in PsA pts is associated with male gender and axial disease. PsA pts with nail involvement are more often disabled, more often are chronic smokers, have significantly worse disease status as measured by disease activity; they are more likely to have more severe (erosive) peripheral arthritis of feet, higher frequency of heel enthesitis and dactylitis, higher psoriasis disease severity, lower frequency of MDA achievement, and worse quality of life and work productivity according to PRO’s. Detection of nail involvement is critical for choice of treatment approach and better outcomes.References:[1]Mease PJ et al.J Rheumatol, 2020Disclosure of Interests:None declared.