Prevalence of Musculoskeletal Symptoms in Patients with Psoriasis and Predictors Associated with the Development of Psoriatic Arthritis: Retrospective Analysis of a US Claims Database.

Introduction: Psoriasis (PsO) is associated with the development of psoriatic arthritis (PsA). Patients with PsO often experience pre-PsA musculoskeletal (MSK) symptoms, leading to potential structural damage and substantial disease burden with impact on function. The objective of this study is to describe prevalence rates and evidence of MSK symptoms, including incidence of comorbid PsA diagnosis, in patients newly diagnosed with PsO and identify factors associated with PsA diagnosis. Methods: This retrospective analysis included administrative claims from the Optum Research Database for adult patients with a new PsO diagnosis between January 2008 and February 2019. Eligible patients had ≥ 2 claims for PsO on unique dates, were aged ≥ 18 years at the date of the first claim with a diagnosis of PsO (index date), and had continuous enrollment with medical and pharmacy coverage for 12 months before (baseline period) and ≥ 12 months following the index date. Primary outcomes were incidence of comorbid PsA diagnosis, prevalence of MSK symptoms other than PsA, and evidence of MSK symptoms collected at baseline and assessed in 12-month intervals through 60 months. Results: Of the 116,203 patients with newly diagnosed PsO, 110,118 were without baseline comorbid PsA. High prevalence rates of MSK symptoms among patients with only PsO were seen at baseline (47.1%), 12 months (48.2%), and 60 months (82.1%). Patient age, baseline MSK symptoms, and baseline MSK symptom–related healthcare utilization were associated with increased hazard of a PsA diagnosis. Conclusion: Increased prevalence rates of MSK symptoms and burden are experienced by patients newly diagnosed with PsO through 60 months of follow-up. Several baseline factors were associated with increased risk of PsA diagnosis. Plain Language Summary: A Study to Look at Symptoms of Muscles, Joints, and Bones in Patients with Psoriasis and Whether They Can Predict a Diagnosis of Psoriatic Arthritis Psoriasis is an inflammatory skin disease that results in areas of significant itchiness, pain, and scaling, and ultimately decreases patient quality of life. Psoriasis affects approximately 2–4% of the general US population and 1.3–2.2% of the UK population. Some patients with psoriasis may experience musculoskeletal symptoms and may go on to develop psoriatic arthritis. The goal of this study was to determine the frequency of patients with psoriasis who experienced complaints of musculoskeletal pain prior to and/or following their psoriasis diagnosis, and whether these were associated with further probability of developing psoriatic arthritis. Using a large US-based database with data from approximately 115,000 patients with newly diagnosed psoriasis, we determined the percentage of newly diagnosed psoriasis patients with existing musculoskeletal pain complaints within 12 months of their initial diagnosis. We found that 47% of newly diagnosed patients had previous musculoskeletal pain complaints, with joint pain, back pain, and overall fatigue representing the most common forms. Notably, psoriasis patients with previous joint pain were approximately 50% more likely to develop psoriatic arthritis compared with patients with no previous joint pain. Furthermore, patients with previous other forms of arthritis were nearly twice as likely to develop psoriatic arthritis. This study provides additional support that existing musculoskeletal pain in patients with newly diagnosed psoriasis may predict the potential future onset of psoriatic arthritis. These findings will help guide primary care physicians, dermatologists, and rheumatologists in understanding the importance of earlier detection of psoriatic arthritis to provide more appropriate care. [ABSTRACT FROM AUTHOR]