Prevalence of Axial and Peripheral Musculoskeletal Manifestations and Comorbidities in Adult Patients with Psoriatic Arthritis in Qassim, Saudi Arabia

Introduction/objectives: This study aimed to describe the demographic, clinical, and therapeutic characteristics of adult patients with psoriatic arthritis (PsA) in Qassim, Saudi Arabia, and to identify independent predictors of axial and peripheral arthritis.Method: In this retrospective cross-sectional study, 185 adult patients with PsA attending rheumatology and dermatology clinics were reviewed.Associations between axial or peripheral arthritis and demographic, clinical, and comorbidity variables were assessed using chi-square(χ²)/Fisher's exact tests and the Mann-Whitney Z-test, followed by multivariate logistic regression adjusted for age at diagnosis, BMI, and vitamin D deficiency.Results: The cohort was young (mean age 39.2±14.5 years) with balanced gender distribution (96, 51.9% male) and early onset PsA (96, 51.9% diagnosed before age 30).Skin-related symptoms were the most frequent presentation (122, 65.9%).Axial arthritis was uncommon (18, 9.7%); peripheral arthritis affected 60 patients (32.4%).Vitamin D deficiency was highly prevalent (124, 67.0%).Systemic therapy was given to 132 patients (71.4%), most frequently methotrexate (38, 20.5%).Axial arthritis was independently predicted by presenting symptoms (adjusted odds ratio (AOR)=0.189,95% CI 0.056-0.644,p=0.008 for skin-related vs arthritis-dominant presentation).Peripheral arthritis was independently predicted by female gender (AOR=2.137,95% CI 1.117-4.085,p=0.022) and presenting symptoms (AOR=0.057,95% CI 0.023-0.142,p<0.001).Conclusions: PsA in this Saudi cohort is characterized by early onset, balanced gender distribution, a high metabolic comorbidity burden, and conservative biologic use.Presenting symptoms were the strongest independent predictors of both arthritis phenotypes, while female gender predicted peripheral involvement, providing region-specific insights for tailored management.