Background Hand osteoarthritis (HOA) is a common and frequent cause of pain. HOA is a heterogeneous group of disorders with two main subsets including non-erosive disease and erosive, sometimes referred to as inflammatory, HOA. Few studies demonstrated inflammatory ultrasound changes and more severe clinical symptoms in patients with erosive compared with non-erosive disease, however the results are inconclusive.
Objectives The aim was to evaluate progression of pain, stiffness, physical impairment and ultrasound features in patients with erosive and non-erosive HOA in a one-year longitudinal study.
Methods Consecutive patients with symptomatic HOA fulfilling the American College of Rheumatology (ACR) criteria were included in this study. Joint pain and swelling were assessed. Patients reported joint pain on 100 mm visual analogue scale (VAS). Pain, joint stiffness and disability were assessed by the Australian/Canadian OA hand index (AUSCAN). Radiographs of both hands were examined and erosive disease was defined by at least one erosive interphalangeal joint. Synovial hypertrophy and power Doppler signal (PDS) were scored with ultrasound. Synovitis was graded on a scale of 0–3 and osteophytes were defined as cortical protrusions seen in two planes. Patients were examined at baseline and one-year follow-up.
Results Altogether, 129 patients (12 male) with symptomatic nodal HOA were included in this study and followed between April 2012 and January 2015. Out of these patients, 72 had erosive disease. The disease duration (p<0.01) was significantly higher in patients with erosive compared with non-erosive disease at the study entry.
Patients took symptomatic slow-acting drugs (SYSADOA) twice a year, non-steroidal anti-inflammatory drugs (NSAIDs) and analgesics on demand. Duration of morning stiffness (p<0.01) and number of clinically swollen joints (p<0.05) were significantly higher in patients with erosive compared with non-erosive disease at study entry. Duration of morning stiffness (p<0.05) become shorter in patients with erosive, but not in those with non-erosive disease, however the number of clinically swollen joints were not significantly changed at one year follow-up in both groups.
According to the AUSCAN, patients with erosive compared with non-erosive disease had more pain (p<0.05) and stiffness (p<0.01) at study entry. Pain, but not stiffness, got worse (p<0.05) in patients with erosive compared with non-erosive disease. US-detected pathologies such as gray-scale synovitis total score (p<0.001), intensity of PDS (p<0.01) and number of osteophytes (p<0.01) were significantly higher in patients with erosive compared with non-erosive disease at study entry and got worse in gray-scale synovitis total score (p<0.01), intensity of PDS (p<0.01) and numerically also in number of osteophytes (p<0.1) at one-year follow-up. There were no significant differences in consumption of NSAIDs and SYSADOA for OA between both groups during the study.
Conclusions This study shows that pain associated with US-detected synovial hypertrophy, inflammatory signs and osteophyte formation is more severe in patients with erosive HOA than in patients with non-erosive disease and is more likely to progress over one year.
Acknowledgement This work was supported by the project (Ministry of Health, Czech Republic) for consensual development of research organization 023728.
Disclosure of Interest None declared