Abstract
BACKGROUND: Pain is common in hand osteoarthritis (OA) and multiple types may occur. We investigated the prevalence, associated patient characteristics, influence on health-related quality of life (HR-QoL) and response to anti-inflammatory treatment of neuropathic-like pain in inflammatory hand OA. METHODS: Data were analysed from a 6-week, randomized, double-blind, placebo-controlled trial investigating prednisolone treatment in 92 patients with painful inflammatory hand OA. Neuropathic-like pain was measured with the painDETECT questionnaire. Associations between baseline characteristics and baseline neuropathic-like pain were analysed with ordinal logistic regression, association of baseline neuropathic-like pain symptoms with baseline HR-QoL with linear regression, painDETECT and visual analogue scale (VAS) change from baseline to week 6 and interaction of painDETECT with prednisolone efficacy on VAS pain change from baseline to week 6 with generalized estimating equations (GEE). RESULTS: Of 91 patients (79% female, mean age 64) with complete painDETECT data at baseline, 53% were unlikely to have neuropathic-like pain, 31% were indeterminate and 16% were likely to have neuropathic-like pain. Neuropathic-like pain was associated with female sex, less radiographic damage and more comorbidities. Patients with neuropathic-like pain had lower HR-QoL (PCS-6.5 [95% CI -10.4 to -2.6]) than those without. Neuropathic-like pain symptoms remained under prednisolone treatment and no interaction was seen between painDETECT and prednisolone efficacy on VAS pain. CONCLUSIONS: In this study, 16% of inflammatory hand OA patients had neuropathic-like pain. They were more often female, had more comorbidities and had lower QoL than those without. Neuropathic-like pain symptoms remained despite prednisolone treatment and did not seem to affect the outcome of prednisolone treatment. SIGNIFICANCE: Pain is the dominant symptom in hand OA, with an unclear aetiology. In this study, we found that neuropathic-like pain may play a role in hand OA, that it showed associations with female sex, younger age and more comorbidities and that it lowered health-related quality of life in hand OA. Neuropathic-like pain in hand OA seems resistant to prednisolone therapy but did not seem to interfere with the treatment of inflammatory pain with prednisolone.