Duration of clinical remission and low disease activity impacts on quality of life and its domains in psoriatic arthritis patients: results from an Italian multicentre study.

Long-term quality of life (QoL) is significantly compromised in patients with psoriatic arthritis (PsA) and only partially improves achieving remission or low disease activity. The main aim of this study is to evaluate the QoL in PsA patients and to investigate their possible relationship with clinical remission and low disease activity, and with its duration over time. A multicentre cross-sectional observational study has been performed. QoL domains considered were analysed through PROs. Chi2 test was used for analysis of contingency tables, while Mann-Whitney test and Kruskal-Wallis test with Holm's pairwise comparison corrections were used to compare ranks. To evaluate variables associated to the different QoL domains, univariate and multiple linear regressions were used. 143 participants were included in this study. The physical component of the Short Form-36 or Functional Assessment of Chronic Illness Therapy-Fatigue tends to improve with short duration of low or minimal disease activity. However, this is not confirmed for the mental component of SF-36 (MCS), which improved only with longer duration of low/minimal disease activity. This study proves the existence of an inverse relation between disease activity and QoL domains. Apart from low or minimal disease activity, also its persistence over time has a great influence on the patient's perception of their clinical condition; therefore, persistence over time of clinical remission/low disease activity should be added to the latest definition of treat-to-target in PsA.