The Prognostic Value of Pain Phenotyping in Relation to Treatment Outcomes in Patients with Axial Spondyloarthritis Treated in Clinical Practice: A Prospective Cohort Study.

Rikke Asmussen Andreasen,Torkell Ellingsen,Xenofon Baraliakos,Kenneth Egstrup,Inger Marie Jensen Hansen,Hans Christian Horn,Berit Schiøttz-Christensen,Robin Christensen,Vibeke Strand,Claus Aalykke,Jimmi Wied,Lars Erik Kristensen

doi:10.3390/jcm10071469

Abstract

Despite the control of inflammation, many patients with axial spondyloarthritis (axSpA) still report pain as a significant concern. Our objective was to explore the prognostic value of the painDETECT questionnaire (PDQ) in relation to treatment outcomes in axSpA patients treated in clinical practice. AxSpA patients with high disease activity initiating or switching a biological Disease-Modifying Antirheumatic Drug (bDMARD) were eligible. The PDQ score (range: −1 to 38) was used to distinguish participants with nociceptive pain (NcP) mechanisms from participants with a mixed pain mechanism (MP). The primary outcome was the proportion of individuals achieving a 50% improvement of the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI50) at 12 weeks; logistic regression analysis models were used to determine the prognostic value of the nociceptive pain phenotype. Changes in continuous outcomes such as the Assessment of SpondyloArthritis International Society (ASAS) core outcome domains were analyzed using analysis of covariance (ANCOVA). Health-related quality of life (HR-QoL) was addressed using the Medical Outcomes Study SF-36. During a period of 22 months, 49 axSpA patients were included. Twenty (41%) had an NcP phenotype according to the PDQ score. BASDAI50 responses were reported by 40% (8/20) and 28% (8/29) NcP and MP groups, respectively. However, a prognostic value was not found in relation to the primary outcome (crude odds ratio [95% confidence interval]: 1.75 [0.52 to 5.87]). Across most of the secondary outcomes, axSpA NcP phenotype patients were reported having the most improvements in the HR-QoL measures. These data indicate the influence of personalized management strategies according to patients’ pain phenotypes for stratification of axSpA patients in randomized controlled trials.

Highlights

Axial spondyloarthritis includes both patients who have developed structural damage in the sacroiliac joints (radiographic axial spondyloarthritis (r-axSpA), termed ankylosing spondylitis (AS)) and those without radiographic evidence of structural damage (nonradiographic axial spondyloarthritis) [1]
The characteristics of the participants were described for each pain profile: Nociceptive Pain (NcP) and “Mixed Pain” (MP) phenotypes defined by painDETECT questionnaire (PDQ) scores
We found statistically significant differences across the two PDQ classification groups in Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Functional Index (BASFI), Visual Analogue Scale (VAS)-pain, VAS-global, tender joint count (TJC), tender point count (TPC)

Summary

Introduction

Axial spondyloarthritis (axSpA) includes both patients who have developed structural damage in the sacroiliac joints (radiographic axial spondyloarthritis (r-axSpA), termed ankylosing spondylitis (AS)) and those without radiographic evidence of structural damage (nonradiographic axial spondyloarthritis (nr-axSpA)) [1]. Cardinal clinical signs and symptoms of axSpA include inflammatory back pain, stiffness and impaired spinal mobility [2,3]. Persistent pain in axSpA patients without any objective signs of inflammation is challenging for clinicians. Recent studies state that about one-third of axSpA patients have a concomitant neuropathic pain component [8,9]. Nociceptive and neuropathic pain imply that these require different management strategies and a correct pain diagnosis informing the treatment of axSpA patients is highly desirable [10]. The painDETECT questionnaire (PDQ) is a simple, validated patient-based questionnaire, developed as a screening tool to evaluate the likelihood of a present neuropathic pain (NeP) component [11]

Objectives

Methods

Results

Discussion

Conclusion