Disease activity trajectories in early axial spondyloarthritis: results from the DESIR cohort

Factors Associated With Treatment Pathways in Early Axial Spondyloarthritis: A Multistate Analysis of the 10-Year Follow-Up of the DESIR Cohort

OBJECTIVE

Current recommendations for the management of patients with axial spondyloarthritis (axSpA) emphasize the need of an individualized strategy in therapeutic decision-making. The study objectives were to describe therapeutic strategies observed in axSpA, and to assess the factors associated with treatment intensification over time.

METHODS

We included patients with axSpA from the French prospective cohort DESIR (Devenir des Spondylarthropathies Indifférenciées Récentes), with a scheduled 10-year follow-up. A multistate model with 4 ordered treatment states (no treatment, nonsteroidal antiinflammatory drugs [NSAIDs], conventional synthetic disease-modifying antirheumatic drugs [csDMARDs], and tumor necrosis factor inhibitors [TNFi]) was defined, with 6 possible transitions. Restricted mean sojourn times in each state were estimated. Then, predictors of those transitions were assessed by multivariable Cox models.

RESULTS

A total of 686/708 (96.9%) patients who had > 1 visit were analyzed. At cohort entry, 199 (29%) were untreated, 427 (62.2%) were receiving NSAIDs, 60 (8.7%) csDMARDs, and none were receiving TNFi. Over the follow-up period, patients mostly (46.4% of the time) received NSAIDs, followed by TNFi (24.4% of the time). The presence of sacroiliitis on radiographs, inflammatory bowel disease, and articular index were jointly associated with the transition to NSAIDs. Longer duration in the previous state often decreased the hazard of the transition to csDMARDs or TNFi. Worse disease activity outcomes increased the hazard of most transitions.

CONCLUSION

To our knowledge, this was the first study using a multistate model to easily represent different treatment states, detailing the transitions across them and their associated factors. Different time profiles for the management of patients with axSpA were identified, including in those abstaining from treatment up to a significant proportion of patients treated with csDMARDs.

Distinct long-term disease activity trajectories differentiate early on treatment with etanercept in both rheumatoid arthritis and spondylarthritis patients: a prospective cohort study

To characterize disease activity trajectories and compare long-term drug retention between rheumatoid (RA) and spondylarthritis (SpA) patients initiating tumor necrosis factor inhibitor (TNFi) treatment (etanercept). Prospective observational study of RA, axial (AxSpA) and peripheral SpA (PerSpA) patients initiating etanercept during 2004-2020. Kaplan-Meier plots were used for drug retention comparisons and multivariable Cox regression models for predictors of discontinuation. Long-term disease activity trajectories were identified by latent class growth models using DAS28-ESR or ASDAS-CRP as outcome for RA and AxSpA respectively. We assessed 711 patients (450 RA, 178 AxSpA and 83 PerSpA) with a median (IQR) follow-up of 12 (5-32) months. At 5 years, 22%, 30% and 21% of RA, AxSpA and PerSpA patients, respectively, remained on therapy. Etanercept discontinuation was independent of the diagnosis and was predicted by gender and obesity in both RA and SpA groups. Four disease activity (DA) trajectories were identified from 6th month of treatment in both RA and AxSpA. RA patients in remission-low DA groups (33.7%) were younger, had shorter disease duration, fewer comorbidities and lower baseline disease activity compared to moderate (40.6%) & high DA (25.7%) groups. In AxSpA 74% were in inactive-low DA and they were more often males, non-obese and had lower number of comorbidities compared to higher ASDAS-CRP trajectories. In RA and AxSpA patients, disease activity trajectories revealed heterogeneity of TNFi treatment responses and prognosis. Male gender, lower baseline disease activity and fewer comorbidities, characterize a favourable outcome in terms of disease burden accrual and TNFi survival.

Influence of Sex on Early Axial Spondyloarthritis: A Six-Year Longitudinal Analysis From a Large National Cohort

OBJECTIVE

The objective was to determine sex differences in disease outcomes in recent axial spondyloarthritis (SpA) over time.

METHODS

We analyzed the first 6 years of follow-up of the prospective French multicenter DESIR cohort. Patients analyzed had <3 years of disease, were naive to disease-modifying antirheumatic drugs, and fulfilled the Assessment of SpondyloArthritis international Society classification criteria for axial SpA. Disease activity (Ankylosing Spondylitis Disease Activity Score [ASDAS] using the C-reactive protein [CRP] level), patient global assessment (PtGA), CRP level, and radiographic sacroiliitis were compared between men and women (self-reported sex) by linear and logistic mixed-effects models. Models were created for trajectories of disease activity over 6 years in men and women, using k-means.

RESULTS

Of 494 patients analyzed (mean ± SD age 31.9 ± 7.5 years, symptoms duration 20.7 ± 11.7 months), 50.4% were men. Over 6 years of follow-up, both men and women showed clear improvements in ASDAS-CRP, PtGA, and CRP level. Women had higher ASDAS-CRP and PtGA over time compared to men (both P < 0.0001) with overall similar CRP levels (P = 0.089), whereas structural damage increased more in men (P < 0.0001). One-third of both men (33%) and women (34%) belonged to persistent high/very high disease activity trajectories, but ASDAS-CRP was globally higher in women in these trajectories.

CONCLUSION

In early axial SpA, clinical outcomes (disease activity and symptoms) were worse in women than men over 6 years of follow-up, whereas CRP was similar and structural damage was more frequent in men. Although similarly distributed, disease activity scores were higher in women in high/very high disease activity trajectories. Sex appears to be an important contextual factor in axial SpA.

Clinical response trajectories and drug persistence in systemic lupus erythematosus patients on belimumab treatment: A real-life, multicentre observational study

Objective

To obtain real-world data on outcomes of belimumab treatment and respective prognostic factors in patients with systemic lupus erythematosus (SLE).

Methods

Observational study of 188 active SLE patients (median disease duration 6.2 years, two previous immunosuppressive/biological agents) treated with belimumab, who were monitored for SLEDAI-2K, Physician Global Assessment (PGA), LLDAS (lupus low disease activity state), remission (DORIS/Padua definitions), SELENA-SLEDAI Flare Index, SLICC/ACR damage index and treatment discontinuations. Group-based disease activity trajectories were modelled followed by multinomial regression for predictive variables. Drug survival was analysed by Cox-regression.

Results

At 6, 12 and 24 months, LLDAS was attained by 36.2%, 36.7% and 33.5%, DORIS-remission by 12.3%, 11.6% and 17.8%, and Padua-remission by 21.3%, 17.9% and 29.0%, respectively (attrition-corrected). Trajectory analysis of activity indices classified patients into complete (25.5%), partial (42.0%) and non-responder (32.4%) groups, which were predicted by baseline PGA, inflammatory rash, leukopenia and prior use of mycophenolate. During median follow-up of 15 months, efficacy-related discontinuations occurred in 31.4% of the cohort, especially in patients with higher baseline PGA (hazard ratio [HR] 2.78 per 1-unit; 95% CI 1.32-5.85). Conversely, PGA improvement at 3 months predicted longer drug retention (HR 0.57; 95% CI 0.33-0.97). Use of hydroxychloroquine was associated with lower risk for safety-related drug discontinuation (HR 0.33; 95% CI 0.13-0.85). Although severe flares were reduced, flares were not uncommon (58.0%) and contributed to treatment stops (odds ratio [OR] 1.73 per major flare; 95% CI 1.09-2.75) and damage accrual (OR 1.83 per mild/moderate flare; 95% CI 1.15-2.93).

Conclusions

In a real-life setting with predominant long-standing SLE, belimumab was effective in the majority of patients, facilitating the achievement of therapeutic targets. Monitoring PGA helps to identify patients who will likely benefit and stay on the treatment. Vigilance is required for the prevention and management of flares while on belimumab.

Prediction of radiographic progression pattern in patients with ankylosing spondylitis using group-based trajectory modeling and decision trees

OBJECTIVE

This study aimed to identify trajectories of radiographic progression of the spine over time and use them, along with associated clinical factors, to develop a prediction model for patients with ankylosing spondylitis (AS).

METHODS

Data from the medical records of patients diagnosed with AS in a single center were extracted between 2001 and 2018. Modified Stoke Ankylosing Spondylitis Spinal Scores (mSASSS) were estimated from cervical and lumbar radiographs. Group-based trajectory modeling classified patients into trajectory subgroups using longitudinal mSASSS data. In multivariate analysis, significant clinical factors associated with trajectories were selected and used to develop a decision tree for prediction of radiographic progression. The most appropriate group for each patient was then predicted using decision tree analysis.

RESULTS

We identified three trajectory classes: class 1 had a uniformly increasing slope of mSASSS, class 2 showed sustained low mSASSS, and class 3 showed little change in the slope of mSASSS but highest mSASSS from time of diagnosis to after progression. In multivariate analysis for predictive factors, female sex, younger age at diagnosis, lack of eye involvement, presence of peripheral joint involvement, and low baseline erythrocyte sedimentation rate (log) were significantly associated with class 2. Class 3 was significantly associated with male sex, older age at diagnosis, presence of ocular involvement, and lack of peripheral joint involvement when compared with class 1. Six clinical factors from multivariate analysis were used for the decision tree for classifying patients into three trajectories of radiographic progression.

CONCLUSION

We identified three patterns of radiographic progression over time and developed a decision tree based on clinical factors to classify patients according to their trajectories of radiographic progression. Clinically, this model holds promise for predicting prognosis in patients with AS.

Peripheral manifestations are major determinants of disease phenotype and outcome in new onset spondyloarthritis

OBJECTIVES

To delineate the impact of peripheral musculoskeletal manifestations on stratification of disease phenotype and outcome in new-onset spondyloarthritis (SpA), using a prospective observational nationwide inception cohort, the BelGian Inflammatory Arthritis and spoNdylitis cohorT (Be-Giant).

METHODS

Newly diagnosed adult SpA patients, fulfilling the Assessment of SpondyloArthritis International Society (ASAS) criteria for axial or peripheral SpA, were included in Be-Giant and prospectively followed every six months. Peripheral involvement (defined as arthritis, enthesitis and/or dactylitis) was determined in relation to clinically similar patient subsets at baseline and disease activity patterns during two-year follow-up, identified through K-means cluster analysis and latent class growth analysis.

RESULTS

From November 2010 to March 2020, 367 patients were enrolled in Be-Giant, of whom 162 (44%) had peripheral manifestations. Two patient clusters [A, axial predominant (n = 248) and B, peripheral predominant (n = 119)] were identified at diagnosis. Longitudinal analysis (n = 115) revealed two trajectories of disease activity in each cluster: one with persistently high disease activity over time ('High'), the other rapidly evolving to low disease activity ('Low'). In cluster A patients, peripheral manifestations predisposed to the 'High' trajectory [odds ratio (OR) = 2.0, 95% CI: 1.3, 3.1, P = 0.001], despite more rapid initiation of biologics compared with patients without peripheral manifestations (hazard ratio (HR)  = 2.1, 95% CI: 1.0, 4.4, P = 0.04 - Cox proportional-hazards model).

CONCLUSION

Peripheral musculoskeletal manifestations are major determinants of phenotypical diversity in new-onset SpA. Intriguingly, stratification of axial SpA according to concomitant peripheral involvement identified an endotype with an unfavorable outcome despite more prompt therapeutic intensification with biologics. These observations justify an endotype-tailored approach beyond current ASAS/EULAR management recommendations.

Cluster analysis in early axial spondyloarthritis predicts poor outcome in the presence of peripheral articular manifestations

OBJECTIVES

To assess whether two cluster analysis-based axial SpA (axSpA) endotypes (A for purely axial; B for both axial and peripheral) are stable over time and are associated with different long-term disease outcomes.

METHODS

K-means cluster analysis was performed at each visit (until 5 years) on 584 patients from the DESIR cohort, who completed all planned visits, and validated in 232 consecutive axSpA patients from the BeGiant cohort. Cluster stability overtime was assessed by kappa statistics. A generalized linear mixed-effect analysis was applied to compare outcomes between clusters. Classification and regression tree (CART) analysis was performed to determine a decision rule able to assign a given patient to a definite cluster at onset.

RESULTS

Both endotypes remained remarkably stable over time. In the DESIR cohort, patients in cluster B showed higher disease activity, worse functional outcome and higher need for anti-rheumatic drugs than patients in cluster A. CART analysis yielded three main clinical features (arthritis, enthesitis, and dactylitis) that accurately determined cluster assignment. These results could be replicated in the Be-GIANT cohort.

CONCLUSION

Cluster-based axSpA endotypes were reproducible in two different cohorts, stable over time and associated with different long-term outcome. The axSpA endotype with additional peripheral disease manifestations is associated with more severe disease and requires more intensive drug therapy.

CLINICAL TRIAL REGISTRATION

clinicaltrials.gov, https://clinicaltrials.gov, NCT01648907.

Determining factors related to impaired spinal and hip mobility in patients with axial spondyloarthritis: longitudinal results from the DESIR cohort

Objective

To investigate the determinants of impaired spinal and hip mobility in patients with early axial spondyloarthritis (axSpA).

Methods

Five-year longitudinal data from the DEvenir des Spondyloarthrites Indifférenciées Récentes (DESIR) cohort were analysed. Associations were investigated using generalised estimating equations, using Bath Ankylosing Spondylitis Metrology Index (BASMI) linear or each of the five components of BASMI as dependent variables, and clinical and demographic variables as independent variables in univariable models. Multivariable analyses were performed, adjusting for potential confounders.

Results

Data from 644 patients and 5152 visits were analysed. Higher BASMI values were independently and positively associated with Ankylosing Spondylitis Disease Activity Score C reactive protein (ASDAS-CRP) (adjusted B (adjB)=0.21; 95% CI=0.15 to 0.28), MRI spinal inflammation score (adjB=0.11; 95% CI=0.04 to 0.19), enthesitis score (adjB=0.02; 95% CI=0.01 to 0.04) and age (adjB=0.02; 95% CI=0.01 to 0.03). All BASMI components were independently associated with ASDAS-CRP and MRI spinal inflammation, except for maximal intermalleolar distance (reflecting hip mobility), which was not associated with MRI spinal inflammation.

Conclusion

In early axSpA, spinal mobility impairment is independently determined by clinical disease activity, MRI spinal inflammation, enthesitis and age. The influence of spinal inflammation prevails in early axSpA, as opposed to spinal structural damage, which may become more relevant in later disease stages.

Identifying Trajectories of Radiographic Spinal Disease in Ankylosing Spondylitis: A 15-year follow up study of the PSOAS Cohort

OBJECTIVES

Little is known with certainty about the natural history of spinal disease progression in Ankylosing Spondylitis (AS). Our objective was to discover if there were distinct patterns of change in vertebral involvement over time and to study associated clinical factors.

METHODS

Data were analyzed from the Prospective Study of Outcomes in Ankylosing Spondylitis (PSOAS) observational cohort. All patients met modified New York Criteria for AS and had ≥2 sets of radiographs scored by modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS) by two independent readers between 2002-2017. Group-based trajectory modeling (GBTM) was used to classify patients into distinct groups of longitudinal mSASSS considering sociodemographic and clinical covariables. The optimal trajectory model and number of trajectories was selected using Nagin's Bayesian information criterion (BIC).

RESULTS

A total of 561 patients with 1618 radiographs was analyzed. The optimum number of trajectory groups identified was four (BIC -4062). These groups were subsequently categorized as: non-progressors (204 patients), late-progressors (147 patients), early-progressors (107 patients) and rapid-progressors (103 patients). Baseline predictors associated with higher spinal disease burden groups included: baseline mSASSS, male gender, longer disease duration, elevated C-reactive protein and smoking history. In addition, time-varying anti-TNF use per year was associated with decreased mSASSS progression only in the rapid-progressor group.

CONCLUSIONS

GBTM identified 4 distinct patterns of spinal disease progression in the PSOAS cohort. Male gender, longer disease duration, elevated C-reactive protein and smoking were associated with higher spinal disease groups. Independent confirmation in other AS cohorts is needed to confirm these radiographic patterns.

How do clinical and socioeconomic factors impact on work disability in early axial spondyloarthritis? Five-year data from the DESIR cohort

Objectives

To investigate the impact of clinical and socioeconomic factors on work disability (WD) in early axial spondyloarthritis (axSpA).

Methods

Patients from the DESIR cohort with a clinical diagnosis of axSpA were studied over 5 years. Time to WD and potential baseline and time-varying predictors were explored, with a focus on socioeconomic (including ethnicity, education, job-type, marital/parental status) and clinical (including disease activity, function, mobility) factors. Univariable analyses, collinearity and interaction tests guided subsequent multivariable time-varying Cox survival analyses.

Results

From 704 patients eligible for this study, the estimated incidence of WD among those identified as at risk (n = 663, 94%), and across the five years of DESIR, was 0.05 (95% CI 0.03, 0.06) per 1000 person-days. Significant differences in baseline socioeconomic factors, including lower educational status and clinical measures, including worse disease activity, were seen in patients developing WD over follow-up, compared with those who never did. In the main multivariable model, educational status was no longer predictive of WD, whereas the AS disease activity score (ASDAS) and the BASFI were significantly and independently associated with a higher hazard of WD [HR (95%CI) 1.79 (1.27, 2.54) and 1.42 (1.22, 1.65), respectively].

Conclusion

WD was an infrequent event in this early axSpA cohort. Nevertheless, clinical factors were among the strongest predictors of WD, over socioeconomic factors, with worse disease activity and function independently associated with a higher hazard of WD. Disease severity remains a strong predictor of adverse work outcome even in early disease, despite substantial advances in therapeutic strategies in axSpA.

Factors associated with remission at 5-year follow-up in recent onset axial spondyloarthritis: results from the DESIR cohort

Objective

The factors contributing to long-term remission in axial SpA (axSpA) are unclear. We aimed to characterize individuals with axSpA at the 5-year follow-up to identify baseline factors associated with remission.

Methods

We included all patients from the DESIR cohort (with recent-onset axSpA) with an available Ankylosing Spondylitis Disease Activity Score–CRP (ASDAS-CRP) at 5-year follow-up. Patients in remission (ASDAS-CRP < 1.3) were compared with those with active disease by demographic, clinical, biological and imaging characteristics. A logistic model stratified on TNF inhibitor (TNFi) exposure was used.

Results

Overall, 111/449 patients (25%) were in remission after 5 years. Among those never exposed to TNFi, 31% (77/247) were in remission compared with 17% (34/202) of those exposed to TNFi. Patients in remission after 5 years were more likely to be male, HLA-B27+, have a lower BMI, and a higher education level. Baseline factors associated with 5-year remission in patients never exposed to TNFi included lower BASDAI [adjusted odds ratio (OR_a) 0.9, 95% CI: 0.8, 0.9) and history of peripheral arthritis (OR_a 2.1, 95% CI: 1.2, 5.3). In those exposed to TNFi, remission was associated with higher education level (OR_a 2.9, 95% CI: 1.6, 5.1), lower enthesitis index (OR_a 0.8, 95% CI: 0.7, 0.9), lower BASDAI (OR_a 0.9, 95% CI: 0.9, 0.9) and lower BMI (OR_a 0.8, 95% CI: 0.7, 0.9).

Conclusion

This study highlights the difficulty in achieving 5-year remission in those with recent-onset axSpA, especially for the more active cases, despite the use of TNFi. Socio-economic factors and BMI are implicated in the outcome at 5 years.

Prediction of Work Impact in Axial Spondyloarthritis by the Work Instability Scale: A Prospective Cohort Study of 101 Patients

OBJECTIVE

Axial spondyloarthritis (axSpA) may have an effect on work. The Ankylosing Spondylitis Work Instability Scale (AS-WIS) assesses difficulties at work. The objective of this study was to evaluate the predictive value of the AS-WIS on work impact.

METHODS

This is a prospective cohort study with 2 timepoints (at baseline and after 1.5 yrs) that included patients with axSpA who had paid employment. Patients completed the AS-WIS at baseline and work instability was scored as moderate/high if ≥ 11 (0-20 scale). At follow-up, adverse work outcomes (AWO) were grouped as moderate (short-term sick leave) or severe AWO (long-term sick leave, disability, unemployment). Univariable and multivariable logistic regression analyses were performed to explain AWO.

RESULTS

Of 101 patients, mean age 45 (SD 9) years, 52% male, disease duration was 14 (SD 8) years. The Bath AS Disease Activity Index and the Bath AS Functional Index were 34 (SD 21) and 23 (SD 23), respectively, and 69 (68%) received a tumor necrosis factor inhibitor. At baseline, 46 (46%) patients had moderate/high AS-WIS. At 1.5 years of follow-up, 37 patients (36%) had AWO: 25 patients (25%) a short-term sick leave, and 12 patients (12%, 7/100 patient-years) a severe AWO. Independent baseline factors associated with AWO were a moderate/high AS-WIS score (OR 2.71, 95% CI 1.04-7.22) and shorter disease duration (OR 0.94, 95% CI 0.89-0.99).

CONCLUSION

In patients with axSpA, a moderate/high AS-WIS score was predictive of AWO in this population with well-controlled axSpA. This short questionnaire can be helpful to screen for future difficulties at work.

Disease activity trajectories in rheumatoid arthritis: a tool for prediction of outcome

Objective: Predicting treatment response and disease progression in rheumatoid arthritis (RA) remains an elusive endeavour. Identifying subgroups of patients with similar progression is essential for understanding what hinders improvement. However, this cannot be achieved with response criteria based on current versus previous Disease Activity Scores, as they lack the time component. We propose a longitudinal approach that identifies subgroups of patients while capturing their evolution across several clinical outcomes simultaneously (multi-trajectories). Method: For exploration, the RA cohort BARFOT (n = 2829) was used to identify 24 month post-diagnosis simultaneous trajectories of 28-joint Disease Activity Score and its components. Measurements were available at inclusion (0), 3, 6, 12, 24, and 60 months. Multi-trajectories were found with latent class growth modelling. For validation, the TIRA-2 cohort (n = 504) was used. Radiographic changes, assessed by the modified Sharp van der Heijde score, were correlated with trajectory membership. Results: Three multi-trajectories were identified, with 39.6% of the patients in the lowest and 18.9% in the highest (worst) trajectory. Patients in the worst trajectory had on average eight tender and six swollen joints after 24 months. Radiographic changes at 24 and 60 months were significantly increased from the lowest to the highest trajectory. Conclusion: Multi-trajectories constitute a powerful tool for identifying subgroups of RA patients and could be used in future studies searching for predictive biomarkers for disease progression. The evolution and shape of the trajectories in TIRA-2 were very similar to those in BARFOT, even though TIRA-2 is a newer cohort.

Patient‐reported Impact of Axial Spondyloarthritis on Working Life: Results from the EMAS survey

Objective

To evaluate work‐related issues (WRIs) and their determinants in patients with axial spondyloarthritis (SpA) across Europe.

Methods

The European Map of Axial Spondyloarthritis is a cross‐sectional online survey (2017–2018) of unselected patients with self‐reported axial SpA from 13 European countries. Participants were classified as active or inactive members of the labor force according to the International Labor Organization standards. Those employed reported WRIs due to axial SpA in the past 12 months. Sociodemographic characteristics and patient‐reported outcomes were compared between patients with and without WRIs. Stepwise regression analysis was conducted to identify independent determinants of WRIs.

Results

The sample comprised 2,846 patients with axial SpA, 1,653 were active members of the labor force, 1,450 were employed, and of those employed, 67.7% reported at least 1 WRI. The most frequently reported WRIs were taking sick leave (56.3%), difficulty fulfilling working hours (44.6%), and missing work for doctor’s appointments (34.6%). Of the total sample, 74.1% declared that they had faced or would face difficulties finding a job due to axial SpA. Patients with WRIs were more often female, were less likely to be married or in a relationship, and had a higher educational level, poorer patient‐reported outcomes, and a greater prevalence of anxiety and depression. Multivariable regression showed that WRIs were associated with a higher Bath Ankylosing Spondylitis Disease Activity Index score (odds ratio [OR] 1.30 [95% confidence interval (95% CI) 1.16–1.45]) and the 12‐item General Health Questionnaire score (OR 1.15 [95% CI 1.09–1.22]), and were negatively associated with inflammatory bowel disease (OR 0.58 [95% CI 0.36–0.91]).

Conclusion

Approximately two‐thirds of employed patients experienced WRIs due to axial SpA. Association between disease activity and psychological distress with WRIs suggests the need to ensure that axial SpA patients receive the required support to cope with their working life.

Work Disability in Axial Spondyloarthritis

PURPOSE OF REVIEW

Axial spondyloarthritis (axSpA) is a chronic inflammatory disease that typically affects people of working age. Work-related outcomes are therefore important to study, both from an individual but also a societal perspective. Through this review of the literature, we explore the impact of axSpA on key work outcomes including work and productivity loss and predictors for these.

RECENT FINDINGS

Recent evidence confirms that axSpA is associated with substantial consequences on the ability to work. Reassuringly, early treatment and use of biologics have been associated with improved wok outcomes highlighting the importance of prompt diagnosis and management. High disease activity, labour-intensive jobs, poor physical function and impaired spinal mobility are among identified predictors of adverse work outcomes in axSpA. The impact of axSpA on work outcomes is considerable and necessitates optimal intervention, including suppression of disease activity, to enhance people's chances of remaining in work.

Similar alteration for mental and physical aspects in health-related quality of life over 5 to 8 years in 1347 patients with early arthritis and early inflammatory back pain

Introduction

Health-related quality of life (HRQoL) is a priority for patients. The objectives were to describe the changes in HRQoL over 5–8 years in patients with early arthritis (EA) or early inflammatory back pain (IBP) and to explore factors associated to HRQoL.

Patients and methods

In 2 prospective observational French cohorts (ESPOIR for EA patients and DESIR for early IBP patients), HRQoL was assessed regularly over 5–8 years, using the SF36 physical and mental composite scores (PCS and MCS, range 0–100). Disease activity was assessed by DAS28-ESR and ASDAS-CRP. Univariate and multivariate linear mixed-effect models and trajectory-based mapping were applied.

Results

In all, 1347 patients (701 EA and 646 early IBP) were analysed: mean age 48.4 ± 12.2 and 33.9 ± 8.7 years respectively; mean disease duration 3.4 ± 1.7 and 18.2 ± 10.8 months; and 76.3% and 55.0% females. At baseline, in EA, mean PCS and MCS were respectively 40.2 ± 9.1 and 40.4 ± 11.2 and, in early IBP, were respectively 38.5 ± 8.5 and 39.8 ± 10.9. Over follow-up, HRQoL mean levels improved mostly over the first 6 months (p <  0.001). Two trajectories were evidenced in both diseases. The ‘good HRQoL’ trajectory groups, i.e. 54–61% of patients, reached levels of HRQoL close to population norms. DAS28-ESR and ASDAS-CRP over time were related to PCS (range of explained variance 9–43%, p <  0.001 in the mixed models) but not to MCS.

Conclusion

HRQoL was altered similarly for both physical and mental aspects in EA and early IBP. Disease activity only partly explained HRQoL: the drivers of HRQoL should be further explored.

Electronic supplementary material

The online version of this article (10.1186/s13075-019-1841-y) contains supplementary material, which is available to authorized users.

Uncovering the heterogeneity of disease impact in axial spondyloarthritis: bivariate trajectories of disease activity and quality of life

Objective

The goal of managing axial spondyloarthritis (axSpA) is to improve and maintain patients' health-related quality of life (HRQoL), mainly through targeting towards low disease activity. Here, we aim to gain insight into the joint evolution of HRQoL and disease activity by identifying and characterising latent subgroups of patients with longstanding disease displaying similar trajectories throughout 8  years of follow-up.

Methods

Data from Outcome in Ankylosing Spondylitis (AS) International Study (n=161) and Groningen Leeuwarden AS cohort (n=264) were used. Biennially, HRQoL was assessed by AS Quality of Life (ASQoL) and disease activity by AS Disease Activity Score-C reactive protein (ASDAS-CRP). Bivariate trajectories of these outcomes were estimated by group-based trajectory modelling. Next, trajectories were profiled by comparing the latent groups with respect to baseline factors using analysis of variance and χ² test.

Results

Five bivariate trajectories were distinguished, in which ASQoL and ASDAS-CRP were tightly linked: (t1) low impact of disease; (t2) moderate impact; (t3) high impact with major improvement; (t4) high impact with some improvement; (t5) very high impact. Profiling revealed, for example, that (t1) was characterised by male gender and Human Leucocyte Antigen B27 positivity; (t3) by younger age, shorter symptom duration and biological intake and (t5) by the highest proportion of females.

Conclusions

We identified five bivariate trajectories of HRQoL and disease activity demonstrating a clear mutual relationship. The profiles revealed that both individual-related and disease-related features define the type of disease course in respect to HRQoL and disease activity in axSpA. This may provide clinicians insight into the differences among patients and help in the management of the disease.

Update on the epidemiology, risk factors, and disease outcomes of axial spondyloarthritis

Axial spondyloarthritis (axSpA) is the prototype of a class of a rheumatic chronic inflammatory disease named spondyloarthritis (SpA). The prevalence of axSpA ranges between 0.1% and 1.4% globally, hence showing geographic differences that can be explained mostly by the prevalence of the HLA-B27 antigen. However, not many studies have evaluated the incidence of this disease. Inflammation may be initiated in the enthesis as a consequence of the action of IL-23, which can activate resident T cells. The elevated expression of IL-23 has been explained by three hypotheses: the presence of HLA-B27, variations in the gut microbiome and the biomechanical stress at the enthesis. However, the role of IL-23 in this whole context is still unclear. In axSpA, the presence of syndesmophytes at baseline, systemic inflammation, and smoking may promote the spinal radiographic damage in these patients. The most frequent comorbidity in these patients is osteoporosis, which is directly associated with ankylosis and inflammation.

Identifying Persons with Axial Spondyloarthritis At Risk of Poor Work Outcome: Results from the British Society for Rheumatology Biologics Register

OBJECTIVE

First, to test the hypothesis that, among working patients with axial spondyloarthritis (axSpA), those who report issues with reduced productivity at work (presenteeism) are at higher risk of work absence (absenteeism), and patients who report absenteeism are at higher risk of subsequently leaving the workforce. Second, to identify characteristics of workers at high risk of poor work outcome.

METHODS

The British Society for Rheumatology Biologics Register in Ankylosing Spondylitis has recruited patients meeting Assessment of Spondyloarthritis international Society criteria for axSpA from 83 centers. Data collection involved clinical and patient-reported measures at recruitment and annually thereafter, including the Work Productivity and Activity Impairment scale. Generalized estimating equations were used to identify factors associated with poor work outcomes.

RESULTS

Of the 1188 participants in this analysis who were working at recruitment, 79% reported some presenteeism and 19% some absenteeism in the past week owing to their axSpA. Leaving employment was most strongly associated with previous absenteeism (RR 1.02 per % increase in absenteeism, 95% CI 1.01-1.03), which itself was most strongly associated with previous presenteeism, a labor-intensive job, and peripheral joint involvement. High disease activity, fatigue, a labor-intensive job, and poorer physical function were all independently associated with future presenteeism.

CONCLUSION

Clinical and patient-reported factors along with aspects of work are associated with an increased risk of axSpA patients having a poor outcome in relation to work. This study has identified modifiable factors as targets, facilitating patients with axSpA to remain productive at work.

Adherence to recommendations for the use of anti-tumour necrosis factor and its impact over 5 years of follow-up in axial spondyloarthritis

Objectives

To describe adherence to recommendations for TNFα blocker (TNFb) initiation and continuation in early axial Spondyloarthropathy (axSpA); and to evaluate the impact of adherence to these recommendations over 5 years of follow-up in the DEvenir des Spondyloarthrites Indifférenciées Récentes (DESIR) cohort.

Methods

The first 5 years of follow-up of the DESIR early axSpA cohort were analysed. We evaluated adherence to Assessment of SpondyloArthritis International Society (ASAS) 2003/2006, 2016 and European Medicines Agency recommendations in axSpA patients for: TNFb initiation (patients were adherent if they either commenced TNFb therapy when they met the conditions for initiation or if they did not commence TNFb therapy when conditions were not met) and; TNFb continuation (either when they continued TNFb therapy when conditions to continue were met or when they discontinued when conditions were not met). The impact of adherence to these recommendations on functional disability, quality of life and sick-leave days over 5 years was explored.

Results

A total of 708 patients were analysed: 440 (62.15%), 389 (54.94%) and 335 (47.32%) were considered adherent to ASAS 2003/2006, 2016 and European Medicines Agency recommendations for TNFb initiation, respectively. Adherence to 2003/2006 and 2016 recommendations for TNFb continuation was observed in 47.37 and 49.39% of patients, respectively. According to over 5 years of follow-up, better outcomes (lower BASFI, higher SF-36 and fewer days of sick leave) were found in patients adhering to recommendations for TNFb commencement and continuation.

Conclusion

Less than 50% of patients were treated in agreement with recommendations for TNFb initiation and continuation. Nevertheless, adherence to such recommendations leads to better functional outcomes and fewer days of sick leave, according to long-term follow-up.

In Early Axial Spondyloarthritis, Increasing Disease Activity Is Associated with Worsening of Health-related Quality of Life over Time

OBJECTIVE

In early axial spondyloarthritis (axSpA), data are lacking about the relationship between disease activity and health-related quality of life (HRQOL). We assessed and quantified the association between change in Ankylosing Spondylitis Disease Activity Score (ASDAS) and HRQOL over time in early axSpA.

METHODS

Baseline and 1-year data of patients with axSpA fulfilling the Assessment of Spondyloarthritis international Society (ASAS) classification criteria from the SPondyloArthritis Caught Early (SPACE) cohort were analyzed. Associations between change in ASDAS and in physical (PCS) or mental component summary (MCS) of the Medical Outcomes Study Short Form-36 were tested by linear regression models. Age, sex, ASAS criteria arm, and blue- versus white-collar work were tested for effect modification. Subsequently, these factors and medication were tested for confounding.

RESULTS

There were 161 patients with axSpA [53% male, mean (± SD) age 29.7 (± 7.5) yrs, symptom duration 13.6 (± 7.2) months, HLA-B27-positive 91%, radiographic sacroiliitis 22%] who had ASDAS of 2.5 (± 1.0) and 2.0 (± 0.8), PCS of 28.4 (± 14.3) and 36.9 (± 13.1), and MCS of 48.2 (± 13.8) and 49.3 (± 12.0) at baseline and 1 year, respectively. Per unit increase in ASDAS between baseline and 1 year, PCS worsened by 9.5 points. The same level of disease activity had fewer adverse effects on physical HRQOL in women and white-collar workers.

CONCLUSION

To our knowledge, our data are the first to show that in a broad group of patients with early axSpA, increasing ASDAS is associated with worsening of physical HRQOL, but not mental HRQOL, over time.

Access criteria for anti-TNF agents in spondyloarthritis: influence on comparative 1-year cost-effectiveness estimates

Background

Anti-tumor necrosis factor (anti-TNF) agents are an effective, but costly, treatment for spondyloarthritis (SpA). Worldwide, multiple sets of access criteria aim to restrict anti-TNF therapy to patients with specific clinical characteristics, yet the influence of access criteria on anti-TNF cost-effectiveness is unknown. Our objective was to use data from the DESIR cohort, a prospective study of early SpA patients in France, to determine whether the French anti-TNF access criteria are the most cost-effective in that setting relative to other potential restrictions.

Methods

We used data from the DESIR cohort to create five study populations of patients meeting anti-TNF access criteria from Canada, France, Germany, United Kingdom, and Hong Kong, respectively. For each study population, we calculated the costs and quality-adjusted life years (QALYs) over 1 year of patients treated and not treated with anti-TNF therapy. To control for differences between anti-TNF users and non-users, we used linear regression models to derive adjusted mean costs and QALYs. We calculated incremental cost-effectiveness ratios (ICERs) representing the incremental cost per additional QALY gained by treating with an anti-TNF within each of the five study populations, using bootstrapping to explore the range of uncertainty in costs and QALYs. A series of sensitivity analyses was conducted, including one to simulate the effect of a 24-week stopping rule for anti-TNF non-responders.

Results

Anti-TNF access criteria from France were satisfied by the largest proportion of DESIR patients (27.8%), followed by Germany (25.1%), Canada (23.8%), the UK (12.1%) and Hong Kong (8.6%). Confidence intervals around incremental costs and QALYs in the basecase analysis were overlapping, indicating that anti-TNF cost-effectiveness estimates derived from each subset were similar. In the sensitivity analysis that examined the effect of excluding costs accumulated past 24 weeks by anti-TNF non-responders, the incremental cost per QALY was reduced by approximately 25% relative to the basecase analysis (France: €857,992 vs. €1,105,859; Canada: € 626,459 vs. €818,186; Germany: € 422,568 vs. €545,808); UK €578,899 vs. €766,217; Hong Kong €335,418 vs. €456,850).

Conclusions

Anti-TNF cost-effectiveness is strongly affected by treatment continuation among non-responders. Access criteria could improve anti-TNF cost-effectiveness by defining patients likely to respond.

Electronic supplementary material

The online version of this article (doi:10.1186/s12962-017-0081-8) contains supplementary material, which is available to authorized users.