Increased Frequency of Hand Osteoarthritis in Patients with Primary Sjögren Syndrome Compared with Systemic Lupus Erythematosus

Abstract

Objective.In daily practice, we noticed that hand osteoarthritis (OA) was commonly associated with primary Sjögren syndrome (pSS). Therefore, we aimed to investigate its prevalence in patients with pSS in a controlled study.Methods.The study included patients with pSS and controls with systemic lupus erythematosus (SLE). Standard hand/wrist radiographs were obtained and classified according to the Kellgren-Lawrence system. “Erosive hand OA” was defined according to the Verbruggen-Veys classification.Results.There were 114 patients with pSS (110 women, 51.0 yrs) and 34 patients with SLE (33 women, 42.4 yrs). Among 114 patients with pSS, 42.7% had radiographic, 30.3% symptomatic, and 16.0% erosive hand OA. The prevalences of radiographic (45.5%) and erosive hand OA (14.4%) in 90 patients with pSS with age- and sex-matched patients with SLE were significantly higher than those in patients with SLE (14.7% and 0.0%, p = 0.007 and p = 0.012, respectively). Interobserver reliabilities for diagnosing radiographic and erosive OA were found to be good (ĸ = 0.780 and ĸ = 0.788, respectively). Intraobserver reliabilities for diagnosing radiographic and erosive OA were also good (ĸ = 0.784 and ĸ = 0.825 for FO, and ĸ = 0.722 and ĸ = 0.800 for AB, respectively). The frequency of hand OA in patients with pSS was found to be increased with increasing age (r = 0.513). The mean age of those with erosive hand OA was significantly higher than those without erosive OA (p < 0.001).Conclusion.This study suggests that pSS, conversely to SLE, is more frequently associated with hand OA.