The association of neuropathic pain and disease activity, functional level, and quality of life in patients with ankylosing spondylitis: a cross-sectional study

Abstract

Background/aim: Increased neuropathic pain (NP) symptoms are seen in rheumatologic diseases such as fibromyalgia, osteoarthritis, and rheumatoid arthritis, but no studies have demonstrated a relationship between ankylosing spondylitis (AS) and NP except for a brain imaging study. The aim of this study was to estimate the presence of NP in patients with AS and to investigate how NP was related to disease activity, functional status, and quality of life. Materials and methods: A total of 100 AS patients (71 males and 29 females; median age: 37 years, range: 18–71 years) were included in the study. Pain (visual analog scale (VAS) and the painDETECT questionnaire), disease activity (Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Maastricht Ankylosing Spondylitis Enthesitis Score (MASES), Patient Global Assessment of Disease Activity (PGA), and Ankylosing Spondylitis Disease Activity Score (ASDAS)), functional level (Bath Ankylosing Spondylitis Functional Index (BASFI)), and health-related quality of life (36-Item Short Form Survey (SF-36)) were evaluated. Patients were divided into two groups. Group 1 included patients with possible or likely NP symptoms (painDETECT score of ≥13) and Group 2 included patients without NP symptoms (painDETECT score of <13). Results: Low back pain-VAS, peripheral joint-VAS, BASDAI, PGA, ASDAS, and BASFI scores were significantly higher in Group 1 compared to those of Group 2 (P < 0.05). The SF-36 physical component (PC) score was significantly lower in Group 1 compared to that of Group 2 (P < 0.05). There were no significant differences between the groups regarding SF-36 mental component (MC) scores, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) values and MASES scores. Total painDETECT scores correlated positively with low back pain-VAS, peripheral joint-VAS, morning stiffness-VAS, BASDAI, ASDAS-CRP, ASDAS-ESR, PGA, BASFI, and MASES scores and ESR values, and inversely with SF-36 PC scores. Conclusion: Our results suggest that AS patients should be evaluated in terms of NP in order not to underestimate NP. If clinicians find evidence of likely NP, they should treat the patient with drugs that target NP.

Keywords: Neuropathic pain; ankylosing spondylitis.