Clinical burden of erosive hand osteoarthritis and its relationship to nodes

Objective To describe the clinical burden of erosive osteoarthritis (EOA) of the hand in terms of pain, functioning and health-related quality of life (HRQL) and its relationship to nodal osteoarthritis (OA). Methods Patients with EOA (n=42) and non-EOA (n=194) of the hand were compared. Pain was assessed with the Australian/Canadian Osteoarthritis Hand Index (AUSCAN), the Michigan Hand Outcome Questionnaire (MHQ) and pain intensity upon pressure. Functioning was evaluated with AUSCAN, MHQ, grip strength, pinch grip and hand mobility tests. HRQL was measured with the Short Form-36. Patient satisfaction with hand function and aesthetics were also evaluated. The presence of nodal OA as well as its extent (reflected by the number of nodes) was assessed. Mean differences between patient groups were estimated with linear mixed models. To determine whether differences were independent of the nodal character of the disease, adjustments were made for the number of nodes. Results Patients with EOA experienced more pain, more functional limitation, less satisfaction with hand function and aesthetics and worse hand mobility than patients with non-EOA. HRQL was similar for the two groups. Patients with EOA had more nodes. A higher number of nodes was associated with worse outcome. After correction for the number of nodes, only hand mobility and patient satisfaction remained different between the groups. Conclusion Patients with EOA have a higher clinical burden than those with non-erosive disease. This higher burden is only partly attributed to the erosive disease itself, but mainly to the nodal character of the disease.