Brief Report: Association of Inflammation With Development of Erosions in Patients With Hand Osteoarthritis: A Prospective Ultrasonography Study.

OBJECTIVE: To investigate the association between features of ultrasound-detected inflammation and development of erosive disease in patients with hand osteoarthritis (OA) over 2.3 years of followup.

METHODS: The study group comprised 56 consecutive patients with hand OA (mean age 61 years, 86% female) fulfilling the American College of Rheumatology criteria. Effusion, synovial thickening, and power Doppler signal in all interphalangeal (IP) joints were assessed with ultrasonography, using standardized methods, at baseline and followup. Radiographs were scored at both time points for osteophytes/joint space narrowing using the Osteoarthritis Research Society International method and for erosive disease (E phase [erosive] and R phase [remodeling]) using the method described by Verbruggen and Veys. Erosion development was defined as progression from N phase (normal) to E phase or R phase. Joints that were in E phase or R phase at baseline were excluded. Associations were analyzed using generalized estimating equations with adjustment for age, sex, body mass index, and baseline structural abnormalities.

RESULTS: At baseline, 51 IP joints (in 18 patients) and at followup 89 IP joints (in 26 patients) had erosions; thus, erosions developed in 38 IP joints. Moderate/severe synovial thickening and a power Doppler signal at baseline were associated with erosion development (adjusted odds ratio [OR] 8.8, 95% confidence interval [95% CI] 2.4-32.3 and OR 7.1, 95% CI 1.9-26.9, respectively). Persistent inflammation was particularly associated with the development of erosions.

CONCLUSION: Ultrasound-detected features of inflammation are associated with the development of erosions in patients with hand OA, suggesting that inflammation plays a role in the pathogenesis of hand OA and could be a therapeutic target.