The Study: Contreras DG, Barber CEH, Aviña-Zubieta JA, et al. Avoidable hospitalizations in persons with rheumatoid arthritis: A population-based study using administrative data. Arthritis Care Res (Hoboken). 2025 Apr 2. Epub ahead of print.
The Transition from Psoriasis to Psoriatic Arthritis
By Lihi Eder, MD, PhD
Why was this study done? Psoriatic arthritis (PsA) develops in 2-3% of individuals with psoriasis annually, often preceded by a subclinical inflammatory phase. Early identification of patients at risk for PsA remains a clinical challenge due to the absence of simple, accessible biomarkers. High-sensitivity C-reactive protein (hsCRP) is a routinely used biomarker for systemic inflammation, but its predictive value for PsA development has not been established. This study aimed to assess whether elevated hsCRP levels are associated with the future development of PsA in patients with psoriasis.
What were the study methods? The study was conducted within a prospective cohort of 589 psoriasis patients, without PsA at baseline, enrolled between 2006 and 2019. Participants were assessed annually by rheumatologists for PsA development. Baseline hsCRP levels were measured using standardized commercial assays. Multivariable Cox proportional hazards models were used to evaluate the association between hsCRP levels and PsA risk, adjusting for age, sex, psoriasis severity and duration, nail disease, body mass index (BMI), fatigue and medication use.
What were the key findings? During a mean follow-up of 7.5 years, 57 participants developed PsA. Patients who developed PsA had higher baseline hsCRP levels (5.4 mg/L), compared to those who did not (2.9 mg/L). In the multivariable model, each 1 mg/L increase in hsCRP was associated with a 4% increased risk of PsA (hazard ratio 1.04, 95% confidence interval [CI] 1.01–1.06). This association was consistent across sexes and unaffected by BMI. Higher hsCRP levels were also associated with arthralgia, obesity and female sex at baseline.
What were the main conclusions? Elevated hsCRP levels independently predicted the future development of PsA in patients with psoriasis, even after accounting for established clinical risk factors.
What are the implications for patients & clinicians? hsCRP, an inexpensive and widely available biomarker, may aid in identifying psoriasis patients at higher risk for PsA. While not sufficient alone for risk prediction, hsCRP could enhance early detection efforts when combined with clinical tools, enabling timely referral and potentially preventive interventions.
The Study: Eder L, Li X, Chandran V, et al. Association of higher levels of high-sensitivity C-reactive protein with future development of psoriatic arthritis in psoriasis: A Prospective Cohort Study. Arthritis Care Res (Hoboken). 2025 Apr 2. Epub ahead of print.
