Impact of the neuropathic component of pain syndrome on clinical and laboratory activity and quality of life in patients with psoriatic arthritis

Abstract

Background: psoriatic arthritis (PA), even in cases with timely initiation of appropriate therapy, is inevitably associated with pain syndrome which includes a neuropathic component. The neuropathic pain (NP) can be considered as a complication of chronic arthropathy, simulating insufficient efficacy of anti-rheumatoid drugs. Aim: to estimate the prevalence of NP in patients with PA and to determine the correlation between NP and patient gender, activity, disease duration, central sensitization (CS) and quality of life. Patients and Methods: the study included 88 patients with PA. The number of tender joints (TJ) and the number of swollen joints (SJ) were counted in all patients. Also, pain intensity was evaluated by the visual analogue scale (VAS) and the level of C-reactive protein (CRP) was measured. The disease activity in patients with PA was assessed using the DAPSA index. A neurologist relied on the PainDETECT questionnaire to identify NP, CS and quality of life in the patients (SF-36). If PainDETECT was above 19 scores, the patients underwent physical examination to confirm NP. Results: patients with PA were split into two groups: with NP (NP+) — 18 (20.4%) subjects and without NP (NP-) — 60 (79.6%) subjects. The NP+ group consisted of older patients (p=0.001), with higher mean VAS scores for paint severity (р=0.008) and a higher mean number of TJ (р=0.014). No differences were found between the groups as regards the mean level of CRP (р=0.880), the mean DAPSA index value (p=0.213), the mean disease duration (p=0,385), and the mean number of SJ (р=0.197). According to the SF-36 questionnaire, the quality of life (QoL) was reduced in all patients. In NP+ group the mean values of the physical component of quality of life were significantly lower than in NP- group (p=0,012). However, such significant difference was not found for the values of psychological component (р=0.239). The prevalence of clinically important CS was significantly higher in the NP+ group patients (р=0.005). Conclusion: the prevalence of NP was common among PA patients which, to a certain extent, may "overestimate" the disease activity due to the patient's subjective judgements about PA severity, serve as a sign of chronic inflammation and reduce quality of life. KEYWORDS: psoriatic arthritis, neuropathic pain, chronic pain syndrome, quality of life, central sensitization, erosive arthritis. FOR CITATION: Akulinushkina E.Yu., Ivanova L.V., Yakupova S.P., Yakupov E.Z. Impact of the neuropathic component of pain syndrome on clinical and laboratory activity and quality of life in patients with psoriatic arthritis. Russian Medical Inquiry. 2023;7(3):113–117 (in Russ.). DOI: 10.32364/2587-6821-2023-7-3-113-117.