Clinical peripheral enthesitis in the DESIR prospective longitudinal axial spondyloarthritis cohort

We aimed to describe the prevalence and characteristics of peripheral enthesitis in recent onset axial spondyloarthritis, estimate the incidence of peripheral enthesitis over time, and determine the factors associated with the presence of peripheral enthesitis.

708 patients with recent onset axial spondyloarthritis were enrolled in the DESIR cohort ( prospective multi-centre, longitudinal). Data regarding the patients and spondyloarthritis characteristics at baseline with a specific focus on enthesitis and occurrence of peripheral enthesitis were collected during the five years of follow-up.

At inclusion, 395 patients (55.8%) reported peripheral enthesitis. The locations were mainly the plantar fascia (53.7%) and the Achilles tendon (38.5%). During the 5-year follow-up period, 109 additional patients developed peripheral enthesitis resulting in an estimated (Kaplan-Meier method) percentage of 71% (95% CI: 68-75). Variables associated with peripheral enthesitis in the univariate analysis were: older age, male gender, absence of HLA B27, MRI sacroiliitis and fulfilled Modified NY criteria, presence of anterior chest wall pain, peripheral arthritis, dactylitis, psoriasis, high BASDAI, BASFI, mean score ASAS-and the use of NSAIDs. Only the history of anterior chest wall pain and of peripheral arthritis were retained in the multivariate analysis (odds ratio (OR)=1.6 [95% confidence interval [1.1-2.3], and OR=2.1 [1.4-3.0], respectively).

This study highlights the high prevalence of peripheral enthesitis in recent onset axial spondyloarthritis, and suggests that in combination with peripheral arthritis, enthesitis might have an impact on the burden of the disease.