Abstract Background/Aims Psoriatic arthritis (PsA) is a form of inflammatory arthritis affecting up to 30% of those with psoriasis. It has a considerable impact on patients’ functional capacity and quality of life. Studies have shown an increased prevalence of depression in patients with PsA which can contribute to reduced likelihood of disease remission. Smartphone applications have been developed to monitor symptoms in patients with rheumatic diseases. We used experience sampling to assess the relationship between daily PsA symptom burden using the PsAID-9 questionnaire and mood components utilising the validated Mood Zoom (MZ) questionnaire. Methods Participants (n = 25) with PsA aged ≥18 and <80 years, meeting the CASPAR criteria were recruited from rheumatology clinics at a single centre. At baseline, disease impact was assessed using the Psoriatic Arthritis Impact of Disease-9 (PsAID-9) questionnaire. Participants used the Mezurio smartphone application daily for 28 days to collect data on the PsAID-9 and Mood Zoom questionnaires. MZ comprises 10-items assessing mood symptoms on a 5-point Likert scale. The relationship between daily fluctuations in PsA symptoms and each mood component was assessed using linear mixed-effect (LMER) models. Likelihood ratio testing and Chi-square tests were used to identify statistical significance. Each model controlled for gender and PsAID-9 remission at baseline. Results Mean (SD) age was 49.6 (12.05) years. Sixteen had co-morbid psoriasis. Mean (SD) PsAID-9 scores were 3.28 (1.92). There was a bi-directional association between the mood components of MZ and total PsAID-9 score for each day, as shown in Table 1. Conclusion This study has demonstrated a relationship between daily fluctuations in disease burden and mood. This is the first study to pilot a daily assessment of disease impact versus traditional longer interval collections. Whilst these data demonstrate an association between mood and disease symptoms, they do not allow us to make inferences on the causal effect of mood on symptoms and vice versa. Further research into the relationship between mood and disease burden in PsA are warranted. Disclosure D. McGagh: None. N. McGowan: None. Y. Wu: None. C. Hinds: None. K.E.A. Saunders: None. L.C. Coates: None.