Predictors of remission in people with axial spondyloarthritis: A systematic literature review

Key messages

• This is the first study systematically summarising predictors of remission in people with axSpA.

• Younger age, HLA-B27 positivity, male gender, lower baseline BASDAI, lower baseline BASFI, lower baseline ASDAS-CRP, treatment with TNFi, and concomitant use of csDMARDs, were the most consistent predictors of remission.

• Considering the observed heterogeneity of predictors and differences in study design, further well-designed prognostic studies are needed to confirm and allow generalisation of these predictors to the general axSpA population.

Abstract

Background

Achievement of remission is a desirable outcome and the identification of predictors of remission may aid in the clinical management of axial spondyloarthritis (axSpA). Our aim was to summarise predictors of remission in people with axSpA.

Methods

In this systematic literature review (SLR), we searched MEDLINE, EMBASE, and Cochrane CENTRAL from their inception to May 20, 2022, and 2020-2021 American College of Rheumatology (ACR) and European Alliance of Associations for Rheumatology (EULAR) meeting abstracts. We included randomized controlled trials and cohort studies in which prognostic factors associated with remission were investigated by multivariable analysis.

Results

The SLR comprised 21 articles from 4592 citations. Three studies investigated “sustained remission” (≥3 consecutive visits), while the other assessed “point remission” (at single points in time, varying from 12 weeks to 8 years). The most used remission criteria were Ankylosing Spondylitis Disease Activity Score (ASDAS) inactive disease (14 studies) and Assessment of SpondyloArthritis international Society partial remission criteria (11 studies). Younger age, HLA-B27 positivity, male gender, lower baseline Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), lower baseline Bath Ankylosing Spondylitis Functional Index (BASFI), lower baseline ASDAS-C-reactive protein, treatment with tumour necrosis factor inhibitors (TNFi), and concomitant use of conventional synthetic disease-modifying anti-rheumatic drugs (csDMARDs), were the most consistent predictors of remission. Additionally, shorter disease duration, lower Health Assessment Questionnaire for the spondyloarthropathies and TNFi naivety were predictors of remission in two studies. Other factors were found to be predictors of remission in one study only.

Conclusions

Predictors of remission in axSpA were identified. However, many of these predictors were only identified in 1-2 studies. Considering the differences in study design, further well-designed prognostic studies are needed to confirm and allow generalisation of these predictors to the general axSpA population.

Introduction

The primary goal of treating patients with axial spondyloarthritis (axSpA) is to maximise long term health-related quality of life through control of symptoms and inflammation, prevention of progressive structural damage, and preservation or normalisation of function and social participation [1]. With the increasing use of biological agents in the treatment of axSpA in recent years, aiming for clinical remission is now a major treatment goal as outlined in current treat-to-target recommendations [2]. However, at present, there is no clear, universally accepted definition of remission in axSpA [3], [4], [5], [6], [7].

Two main definitions of clinical remission/inactive disease have been proposed: 1) Assessment in Spondyloarthritis International Society (ASAS) partial remission (PR) [8], defined by a value no greater than 20 on a 0-100 scale in four domains: pain represented by the visual analogue scale (VAS) score (0–100); function represented by the Bath Ankylosing Spondylitis Functional Index (BASFI) score (0–100); inflammation represented either by the mean of the two morning stiffness-related Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) questions (item 5 or 6), [8]; and 2) Ankylosing Spondylitis Disease Activity Score (ASDAS) inactive disease (ID), defined by an ASDAS score<1.3 [9], with ASDAS C-reactive protein (CRP) or ASDAS erythrocyte sedimentation rate (ESR) being calculated using a formula that weights five items: back pain (BASDAI question 2), peripheral joint complaints (BASDAI question 3), duration of morning stiffness (BASDAI question 6), patient global assessment, and CRP (ASDAS-CRP) or ESR level (ASDAS-ESR) [10], [11], [12].

Achievement of remission has been associated with retardation of progression of structural damage [13], [14], [15] and better health outcomes, namely improved physical function, health-related quality of life and work productivity [16,17]. Therefore, remission is a desirable outcome in axSpA, and the identification of predictors of remission may further aid in the clinical management of the disease, offering the possibility of more individualised treatment plans and allowing health care professionals to better communicate with patients regarding the course and prognosis of their condition.

This systematic literature review (SLR) aimed to identify predictors of remission in people with axSpA. This is the first SLR performed about this topic.