Psoriatic arthritis (PsA), a heterogeneous chronic inflammatory immune-mediated disease characterized by musculoskeletal inflammation (arthritis, enthesitis, spondylitis, and dactylitis), generally occurs in patients with psoriasis. PsA is also associated with uveitis and inflammatory bowel disease (Crohn’s disease and ulcerative colitis). To capture these manifestations as well as the associated comorbidities, and to recognize their underlining common pathogenesis, the name of psoriatic disease was coined. The pathogenesis of PsA is complex and multifaceted, with an interplay of genetic predisposition, triggering environmental factors, and activation of the innate and adaptive immune system, although autoinflammation has also been implicated. Research has identified several immune-inflammatory pathways defined by cytokines (IL-23/IL-17, TNF), leading to the development of efficacious therapeutic targets. However, heterogeneous responses to these drugs occur in different patients and in the different tissues involved, resulting in a challenge to the global management of the disease. Therefore, more translational research is necessary in order to identify new targets and improve current disease outcomes. Hopefully, this may become a reality through the integration of different omics technologies that allow better understanding of the relevant cellular and molecular players of the different tissues and manifestations of the disease. In this narrative review, we aim to provide an updated overview of the pathophysiology, including the latest findings from multiomics studies, and to describe current targeted therapies.

ObjectiveThe aim of this study was to evaluate the discriminant capability of the Patient Acceptable Symptom State (PASS) according to disease activity, remission/low disease activity indices and quality of life indices in patients with psoriatic arthritis (PsA).MethodsConsecutive patients with PsA were enrolled in this cross-sectional study. At each visit, the patients underwent a complete physical examination and their clinical/laboratory data were collected. Disease activity was assessed using the Disease Activity Score for Psoriatic Arthritis (DAPSA) and remission/low disease activity using the DAPSA minimal disease activity (MDA) and very low disease activity (VLDA) criteria. The Psoriatic Arthritis Impact of Disease (PsAID) and the Health Assessment Questionnaire-Disability Index scores were also collected. Finally, PASS was assessed by asking all patients to answer yes or no to a single question.ResultsPatients who answered yes to PASS showed a significantly better overall mean DAPSA score than those who were not in PASS. Furthermore, patients in PASS showed a significantly lower level of systemic inflammation, lower Leeds Enthesitis Index score, a significantly lower impact of disease (PsAID), lower pain and better function than patients who answered no to PASS. A moderate to good agreement was found between PASS, MDA, DAPSA low disease activity and PsAID score ≤4. Good sensitivity and specificity were found with PASS with respect to DAPSA low disease activity, and although PASS is sensitive in the identification of patients with MDA, DAPSA remission and VLDA it lacks of specificity.DiscussionThis study showed that PASS might be used as an alternative to determine disease activity in patients with PsA in real clinical practice, mainly in patients with low disease activity according to DAPSA criteria.

Introduction The aim of this study was to evaluate the impact of comorbidities on disease activity, patient’s impact of the disease, patient global assessment, and function in psoriatic arthritis (PsA). Methods Consecutive PsA patients were enrolled in this cross-sectional study. During the visit, the patients underwent a complete physical examination and clinical/laboratory data were collected, including type and number of comorbidities, recorded as simple comorbidity count (SCC). Disease activity was assessed using the Disease Activity Score for Psoriatic Arthritis (DAPSA) and the Minimal Disease Activity (MDA) was also evaluated. The Psoriatic Arthritis Impact of Disease (PsAID), the Health Assessment Questionnaire-Disability Index (HAQ-DI), and the Patient Global Assessment of disease activity (PtGA) were also collected. Results A total of 144 patients were enrolled. At least one comorbidity was registered in 104 (72.2%) patients. The SCC was associated with DAPSA ( β = 1.48, p = 0.013), PsAID ( β = 0.41, p < 0.01), HAQ-DI ( β = 0.11, p < 0.01) and PtGA ( β = 0.50, p < 0.01). The comorbidities that showed an impact on outcome measures were anxiety and fibromyalgia (FM). Anxiety showed an impact on DAPSA ( β = 14.46, p < 0.001), PsAID ( β = 1.98, p = 0.039) and HAQ-DI ( β = 0.54, p = 0.036). FM showed an impact on DAPSA ( β = 6.46, p = 0.025), PsAID ( β = 2.88, p < 0.001), HAQ-DI ( β = 0.70, p < 0.001), PtGA ( β = 2.00, p = 0.014), and MDA ( β = − 2.79, p = 0.01). The median PtGA value was different among patients with different numbers of comorbidities . Conclusions This study showed that comorbidities, either as a simple comorbidity count number or as single comorbidity, might have an impact on the main domains affecting PsA patients in real clinical practice.