The prevalence of chronic pain in children and adolescents: a systematic review update and meta-analysis

ABSTRACT

Chronic pain, defined as persistent or recurring pain or pain lasting longer than 3 months, is a common childhood problem. The objective of this study was to conduct an updated systematic review and meta-analysis on the prevalence of chronic pain (ie, overall, headache, abdominal pain, back pain, musculoskeletal pain, multisite/general pain, and other) in children and adolescents. EMBASE, PubMed, CINAHL, and PsycINFO were searched for publications between January 1, 2009, and June 30, 2023. Studies reporting population-based estimates of chronic nondisease related pain prevalence in children or adolescents (age ≤ 19 years) were included. Two independent reviewers screened articles based on a priori protocol. One hundred nineteen studies with a total of 1,043,878 children (52.0% female, mean age 13.4 years [SD 2.4]) were included. Seventy different countries were represented, with the highest number of data points of prevalence estimates coming from Finland and Germany (n = 19 each, 4.3%). The overall prevalence of chronic pain in children and adolescents was 20.8%, with the highest prevalence for headache and musculoskeletal pain (25.7%). Overall, and for all types of pain except for back pain and musculoskeletal pain, there were significant differences in the prevalence between boys and girls, with girls having a higher prevalence of pain. There was high heterogeneity (I 2 99.9%). Overall risk of bias was low to moderate. In summary, approximately 1 in 5 children and adolescents experience chronic pain and prevalence varies by pain type; for most types, there is higher pain prevalence among girls than among boys. Findings echo and expand upon the systematic review conducted in 2011.

ASDAS-CRP and ASDAS-ESR cut-offs for disease activity states in axial spondyloarthritis - Are they interchangeable?

OBJECTIVE

Ankylosing Spondylitis Disease Activity Score with C-reactive protein (ASDAS-CRP) is recommended over erythrocyte sedimentation rate (ASDAS-ESR) to assess disease activity in axial spondyloarthritis (axSpA). Although ASDAS-CRP and ASDAS-ESR are not interchangeable, the same disease activity cut-offs are used for both. We aimed to estimate optimal ASDAS-ESR values corresponding to the established ASDAS-CRP cut-offs (1.3, 2.1 and 3.5) and investigate the potential improvement of level of agreement between ASDAS-ESR and ASDAS-CRP disease activity states when applying these estimated cut-offs.

METHODS

We used data from axSpA patients initiating a tumour necrosis factor inhibitor from nine European registries. ASDAS-ESR cut-offs were estimated using the Youden index. Level of agreement between ASDAS-ESR and ASDAS-CRP disease activity states was compared against each other.

RESULTS

In 3,664 patients, mean ASDAS-CRP was higher than ASDAS-ESR at both baseline (3.6 and 3.4, respectively) and aggregated follow-up at 6, 12, or 24 months (1.9 and 1.8, respectively). The estimated ASDAS-ESR values corresponding to the established ASDAS-CRP cut-offs were 1.4, 1.9 and 3.3. By applying these cut-offs, the proportion of discordance between disease activity states according to ASDAS-ESR and ASDAS-CRP decreased from 22.93% to 19.81% in baseline data but increased from 27.17% to 28.94% in follow-up data.

CONCLUSION

We estimated the optimal ASDAS-ESR values corresponding to the established ASDAS-CRP cut-off values. However, applying the estimated cut-offs did not increase the level of agreement between ASDAS-ESR and ASDAS-CRP disease activity states to a relevant degree. Our findings did not provide evidence to reject the established cut-off values for ASDAS-ESR.

Patient-reported outcomes in axial spondyloarthritis and psoriatic arthritis patients treated with secukinumab for 24 months in daily clinical practice

OBJECTIVES

In patients with axial spondyloarthritis (axSpA) or psoriatic arthritis (PsA) initiating secukinumab, we aimed to assess and compare the proportion of patients achieving 6-, 12- and 24-month patient-reported outcomes (PRO) remission and the 24-month retention rates.

PATIENTS AND METHODS

Patients with axSpA or PsA from 16 European registries, who initiated secukinumab in routine care were included. PRO remission rates were defined as pain, fatigue, Patient Global Assessment (PGA) ≤2 (Numeric Rating Scale (NRS) 0-10) and Health Assessment Questionnaire (HAQ) ≤0.5, for both axSpA and PsA, and were calculated as crude values and adjusted for drug adherence (LUNDEX). Comparisons of axSpA and PsA remission rates were performed using logistic regression analyses (unadjusted and adjusted for multiple confounders). Kaplan-Meier plots with log-rank test and Cox regression analyses were conducted to assess and compare secukinumab retention rates.

RESULTS

We included 3087 axSpA and 3246 PsA patients initiating secukinumab. Crude pain, fatigue, PGA and HAQ remission rates were higher in axSpA than in PsA patients, whereas LUNDEX-adjusted remission rates were similar. No differences were found between the patient groups after adjustment for confounders. The 24-month retention rates were similar in axSpA vs. PsA in fully adjusted analyses (HR [95 %CI] = 0.92 [0.84-1.02]).

CONCLUSION

In this large European real-world study of axSpA and PsA patients treated with secukinumab, we demonstrate for the first time a comparable effectiveness in PRO remission and treatment retention rates between these two conditions when adjusted for confounders.

The worldwide prevalence of psoriatic arthritis-a systematic review and meta-analysis

OBJECTIVES

Previous attempts to pool prevalence studies in PsA have failed to take account of important methodological differences between studies which may have created biased estimates. The aim of this review is to estimate the prevalence of PsA within the adult general population worldwide, considering potential differences between population-based and health administrative studies separately.

METHODS

Four electronic databases were systematically searched for articles reporting the prevalence of PsA. Data were pooled to generate worldwide prevalence estimates. Where sufficient data were available, results were summarised by continent.

RESULTS

30 studies were identified, with half from Europe (n = 15). Thirteen population-based studies were identified comprising >92 000 adults, plus 17 studies (>180 million adults) based on health administrative data. The worldwide prevalence of PsA was 112 per 100 000 adults. The prevalence of PsA estimated using populations-based studies was 113 per 100 000 with continent-specific estimates of 207 (Europe), 64 (North America), and 37 (Asia) per 100 000. Health administrative studies gave a global prevalence of 109 per 100 000 with continent-specific prevalence of 175 (Europe), 147 (North America), 78 (Asia), and 17 (South America).

CONCLUSION

This review compiles currently available estimates of PsA prevalence in the general population into global and continent-based estimates and considers important study design characteristics. There is wide variability between continents and data in some geographical areas are sparse but available evidence suggests that PsA is more common in Europe and North America compared with Asia and South America, and current best estimates suggest a global prevalence of 112 per 100 000 adults.

Access to Chronic Pain Services for Adults from Minority Ethnic Groups in the United Kingdom (UK): a Scoping Review

BACKGROUND

Chronic pain services in the UK are required to provide services which meet the diverse needs of patients, but little is known about the access and use of these services by minority ethnic groups.

OBJECTIVE

To assess the available evidence regarding the ethnic profile of adults who access secondary and tertiary chronic pain services in the UK.

METHODS

A scoping review was conducted (August 2021-October 2021), comprising comprehensive literature searches using Embase, Medline and CINAHL databases and the grey literature. Studies were included if they reported on (i) access to chronic pain services in secondary and/or tertiary care in the UK, (ii) adults and (iii) stated the ethnicity of the involved participants. Studies were included if published between 2004 and 2021, as demographic data during this period would be broadly representative of the UK population, as per the 2021 UK census. A descriptive synthesis of the extracted data was performed.

RESULTS

The search yielded 124 records after duplicates were removed. Following title and abstract screening, 44 full texts were screened, ten of which were included in the review.

CONCLUSIONS

This is the first review to explore access to chronic pain services for adults from minority ethnic groups in the UK. Given the limited number of studies that met the inclusion criteria, the review highlights the need for routine collection of ethnicity data using consistent ethnic categories within UK chronic pain services and increased involvement of minority ethnic groups within chronic pain research. Findings should inform future research that aims to improve access to UK chronic pain services for adults from minority ethnic groups.

Advice to remain active with arm pain reduces disability

BACKGROUND

Arm pain is common amongst working-aged adults and causes substantial work disability. The results of a population-based randomized controlled trial (the ARM trial) suggested that advice to remain active reduced disability after 6 months.

AIMS

To verify ARM trial results amongst people in paid employment.

METHODS

The ARM trial recruited adults with distal arm pain referred for physiotherapy and randomized equally to three groups: wait-listed for physiotherapy (advised to rest); wait-listed for physiotherapy (advised to remain active) or early physiotherapy. The primary outcome was absence of disability at 26 weeks. Secondary analyses were undertaken amongst participants in paid employment.

RESULTS

Amongst 538 trial participants, 347 (64%) were in paid employment, mean age 46.1 years and 47% in manual work. Employed participants were randomized equally to the three arms. Amongst the 271 (78% workers with 26-week data), 43% of those advised to remain active were free from disability, as compared with 37% of those advised to rest. Forty per cent of those who waited for physiotherapy were disability-free as compared with 35% of those treated rapidly. Advice to rest was associated with lower chances of recovery amongst workers who lift/carry weights and those who believed work had caused their symptoms (P = 0.023).

CONCLUSIONS

Although not powered as a trial for workers only, our findings suggest that advising activity was as beneficial for people currently in paid work and may be superior to advice to rest in reducing disability. Addressing harmful beliefs about causation of symptoms has the potential to reduce disability.

Inflammatory Bowel Disease Risk in Patients With Axial Spondyloarthritis Treated With Biologic Agents Determined Using the BSRBR-AS and a MetaAnalysis

OBJECTIVE

To determine, among patients with axial spondyloarthritis (axSpA), whether the risk of inflammatory bowel disease (IBD) varies between patients treated with biologic therapies and those treated with other therapies and, specifically, whether the risk is higher in patients treated with etanercept (ETN).

METHODS

The British Society for Rheumatology Biologics Register in Ankylosing Spondylitis (BSRBR-AS) was used to determine the incidence of IBD during follow-up and to calculate the incidence rate difference (IRD) per 1000 person-years (PY), between biologic treatment and other treatment groups. We then conducted a systematic review, involving observational studies and randomized controlled trials (RCTs), to perform a metaanalysis to quantify the difference in incidence of IBD between treatment groups.

RESULTS

According to the BSRBR-AS, among people with axSpA, exposure to biologic therapy was associated with an increased incidence of IBD compared to those who were not exposed to biologic therapy (IRD 11.9, 95% CI 4.3-19.6). This finding was replicated across observational studies but was not seen in placebo-controlled RCTs (IRD 2.2, 95% CI -4.1 to 8.5). Data from the BSRBR-AS do not suggest that excess incidence of IBD is associated with exposure to ETN compared to other anti-tumor necrosis factor (TNF) therapies (IRD -6.5, 95% CI -21.3 to 8.5). RCTs and their extensions suggest a small-yet not statistically significant-absolute increased incidence associated with ETN of between 2.1 and 5.8 per 1000 PY compared to other anti-TNF therapies.

CONCLUSION

There was an excess risk of IBD among persons treated with biologics in observational studies. Only evidence from RCTs suggested that ETN was associated with an increased risk compared to other anti-TNF therapies, albeit with considerable uncertainty.

Treatment of axial spondyloarthritis with biologic and targeted synthetic DMARDs: British Society for Rheumatology guideline scope

Pharmacological management has advanced considerably since the 2015 British Society for Rheumatology axial spondyloarthritis (axSpA) guideline to incorporate new classes of biologic DMARDs (bDMARDs, including biosimilars), targeted synthetic DMARDs (tsDMARDs) and treatment strategies such as drug tapering. The aim of this guideline is to provide an evidence-based update on pharmacological management of adults with axSpA (including AS and non-radiographic axSpA) using b/tsDMARDs. This guideline is aimed at health-care professionals in the UK who care directly for people with axSpA, including rheumatologists, rheumatology specialist nurses, allied health professionals, rheumatology specialty trainees and pharmacists; people living with axSpA; and other stakeholders, such as patient organizations and charities.

One-Third of European Patients with Axial Spondyloarthritis Reach Pain Remission With Routine Care Tumor Necrosis Factor Inhibitor Treatment

OBJECTIVE

To investigate the distribution of patient-reported outcomes (PROs) in patients with axial spondyloarthritis (axSpA) initiating a tumor necrosis factor inhibitor (TNFi), to assess the proportion reaching PRO "remission" across registries and treatment series, and to compare patients registered to fulfill the modified New York (mNY) criteria for ankylosing spondylitis (AS) vs patients with nonradiographic axSpA (nr-axSpA).

METHODS

Fifteen European registries contributed PRO scores for pain, fatigue, patient global assessment (PtGA), Bath Ankylosing Spondylitis (AS) Disease Activity Index (BASDAI), Bath AS Functional Index (BASFI), and Health Assessment Questionnaire (HAQ) from 19,498 patients with axSpA. Changes in PROs and PRO remission rates (definitions: ≤ 20 mm for pain, fatigue, PtGA, BASDAI, and BASFI; ≤ 0.5 for HAQ) were calculated at 6, 12, and 24 months of treatment.

RESULTS

Heterogeneity in baseline characteristics and outcomes between registries were observed. In pooled data, 6 months after the start of a first TNFi, pain score was reduced by approximately 60% (median at baseline/ 6/12/24 months: 65/25/20/20 mm) in patients on treatment. Similar patterns were observed for fatigue (68/32/30/25 mm), PtGA (66/29/21/20 mm), BASDAI (58/26/21/19 mm), BASFI (46/20/16/16 mm), and HAQ (0.8/0.4/0.2/0.2). Patients with AS (n = 3281) had a slightly better response than patients with nr-axSpA (n = 993). The Lund Efficacy Index (LUNDEX)-adjusted remission rates at 6 months for pain/fatigue/PtGA/BASDAI/BASFI/HAQ were 39%/30%/38%/34%/35%/48% for the AS cohort and 30%/21%/26%/24%/33%/47% for the nr-axSpA cohort. Better PRO responses were seen with a first TNFi compared to a second and third TNFi.

CONCLUSION

Patients with axSpA starting a TNFi achieved high PRO remission rates, most pronounced in those fulfilling the mNY criteria and for the first TNFi.

Generating EQ-5D-5L health utility scores from BASDAI and BASFI: a mapping study in patients with axial spondyloarthritis using longitudinal UK registry data

BACKGROUND

Preference-based health-state utility values (HSUVs), such as the EuroQol five-dimensional questionnaire (EQ-5D-5L), are needed to calculate quality-adjusted life-years (QALYs) for cost-effectiveness analyses. However, these are rarely used in clinical trials of interventions in axial spondyloarthritis (axSpA). In these cases, mapping can be used to predict HSUVs.

OBJECTIVE

To develop mapping algorithms to estimate EQ-5D-5L HSUVs from the Bath Ankylosing Disease Activity Index (BASDAI) and the Bath Ankylosing Spondylitis Functional Index (BASFI).

METHODS

Data from the British Society for Rheumatology Biologics Register in Ankylosing Spondylitis (BSRBR-AS) provided 5122 observations with complete BASDAI, BASFI, and EQ-5D-5L responses covering the full range of disease severity. We compared direct mapping using adjusted limited dependent variable mixture models (ALDVMMs) and optional inclusion of the gap between full health and the next feasible value with indirect response mapping using ordered probit (OPROBIT) and generalised ordered probit (GOPROBIT) models. Explanatory variables included BASDAI, BASFI, and age. Metrics to assess model goodness-of-fit and performance/accuracy included Akaike and Bayesian information criteria (AIC/BIC), mean absolute error (MAE) and root mean square error (RMSE), plotting predictive vs. observed estimates across the range of BASDAI/BASFI and comparing simulated data with the original data set for the preferred/best model.

RESULTS

Overall, the ALDVMM models that did not formally include the gap between full health and the next feasible value outperformed those that did. The four-component mixture models (with squared terms included) performed better than the three-component models. Response mapping using GOPROBIT (no squared terms included) or OPROBIT (with squared terms included) offered the next best performing models after the three-component ALDVMM (with squared terms). Simulated data of the preferred model (ALDVMM with four-components) did not significantly underestimate uncertainty across most of the range of EQ-5D-5L values, however the proportion of data at full health was underrepresented, likely due in part to model fitting on a small number of observations at this point in the actual data (4%).

CONCLUSIONS

The mapping algorithms developed in this study enabled the generation of EQ-5D-5L utilities from BASDAI/BASFI. The indirect mapping equations reported for the EQ-5D-5L facilitate the calculation of the EQ-5D-5L utility scores using other UK and country-specific value sets.

OA17 The risk of inflammatory bowel disease in patients with axial spondyloarthritis treated with biologic agents: data from the BSR registry in axial spondyloarthritis (BSRBR-AS) and meta-analysis

Background/Aims

Inflammatory bowel disease (IBD) is one of the extra-musculoskeletal manifestations associated with axial spondyloarthritis (axSpA). A previous meta-analysis reported a pooled prevalence of 6.8% (95% CI 6.1% to 7.7%). Amongst those commencing anti-TNFα therapy in BSRBR-AS it has been reported that patients with IBD were much less likely to have been prescribed etanercept (a soluble fusion protein) in comparison to the monoclonal antibodies in this cohort (adalimumab, certolizumab pegol and golimumab). A large study from Denmark of approximately 80,000 patients with an autoimmune disease (other than IBD) for which anti-TNFα therapy is an indication found a significant excess risk of IBD in those treated with etanercept, an excess which was not observed with other anti-TNFα agents. We therefore aimed to determine, amongst patients in BSRBR-AS, whether the risk of inflammatory bowel disease (IBD) varies between patients treated with biologic and other therapies, and whether specifically the risk is higher in patients treated with etanercept.

Methods

The British Society for Rheumatology Biologics Register in Ankylosing Spondylitis (BSRBR-AS) was used to determine the incidence of IBD during follow-up and to calculate the incidence rate difference (IRD) between biologic treatment and other treatment groups. We thereafter conducted a systematic review (involving observational studies and randomised controlled trials) to perform a meta-analysis to quantify the difference in incidence of IBD between treatment groups.

Results

In BSRBR-AS, among people with axSpA, exposure to biologic therapy was associated with an increased incidence of IBD compared to non-exposed patients (IRD 12.4 95% CI [5.5-19.4]). In meta-analysis, this finding was replicated across observational studies but not seen in placebo controlled RCTs IRD 2.2 95% CI (-4.1-8.5). Data from BSRBR-AS do not suggest that excess incidence of IBD is associated with exposure to etanercept compared to other anti-TNFα therapies (IRD -1.9 per 1000 py 95% CI [-15.2-11.5]). Trials and their extensions suggest a small (and not statistically significant) absolute increased incidence associated with etanercept of between 2.1 and 5.6 per 1000py compared to other anti-TNFα therapies.

Conclusion

An excess risk of IBD amongst persons treated with biologics is likely not causal but evidence from trials suggest that etanercept is associated with an increased risk compared to other anti-TNFα therapies, albeit with considerable uncertainty.

Disclosure

G.J. Macfarlane: Grants/research support; GJM is Chief Investigator a grant from BSR to fund the AS register. BSR received funds from Pfizer, AbbVie and UCB to support this work. R. Biallas: None. L.E. Dean: None. G.T. Jones: Grants/research support; GTJ is Co-Investigator on a grant from BSR to fund the AS register. BSR received funds from Pfizer, AbbVie and UCB to support this work. N. Goodson: Other; NG is Chair of the BSR Registers Committee. O. Rotariu: None.

P272 Pregnancy outcomes in women receiving biological therapy for axial spondyloarthritis

Background/Aims

Axial spondyloarthritis (axSpA) is a chronic inflammatory disease affecting the spine and sacroiliac joints. It is typically diagnosed before the age of thirty-five in patients presenting with pain and stiffness of the lower back. Treatment of axSpA is multidisciplinary and medical management initially consists of non-steroidal anti-inflammatory medications. For patients with high disease activity or poor symptomatic control, treatment may be escalated to biological therapies including, tumour necrosis factor (TNF) alpha inhibitors. Thus, treatment with these powerful medications is likely to coincide with the time that patients may wish to start a family. Currently, there is very limited evidence regarding the safety of biological therapies during pregnancy and the advice to patients is unclear. The aim of this paper is to identify the current evidence regarding pregnancy outcomes following exposure to biological therapy during pregnancy for the treatment of axSpA.

Methods

Methods: A literature search was conducted through Ovid Medline and Embase to identify relevant studies in line with a patient population, intervention, comparator, and outcomes (PICO) model identified prior to this study. An adapted version of the PRISMA 2020 flow diagram guided screening of manuscripts identified during database searches. Data gathered were summarised in a narrative review.

Results

From 15,121 papers identified, 101 were assessed for eligibility and six full papers were included in this study. Five of these studies reported 117 pregnancy outcomes following exposure to TNF-alpha inhibitors (adalimumab, etanercept, certolizumab pegol) for treatment of axSpA during pregnancy. Of these, five pregnancies were reported to have birth defects, for example cerebral ventricle dilatation and premature birth. The final study reported a high proportion of Caesarean sections among women treated with TNF-alpha inhibitors: 83 deliveries (61%) from 136 pregnancies.

Conclusion

There is very little published evidence on the safety of TNF-alpha inhibitors during pregnancy for axSpA and no papers were identified describing pregnancy outcomes in non-TNF biologics. Some additional literature was identified, examining biologic use in pregnancy across a variety of other rheumatological conditions, although it was often not possible to extract data on axSpA separately.

However, existing evidence suggests no increased risk of adverse pregnancy outcomes associated with TNF inhibition in axSpA. There is some evidence that pregnant women may be more likely to undergo Caesarean section rather than vaginal delivery, although it is not clear whether this is due to increased elective or emergency Caesarean section. This review highlights the need for more studies to be conducted on this topic. This would enable more robust evidence-based guidelines to be produced and implemented confidently in clinical practice.

Funding Statement: ELB supported by University of Aberdeen Summer Research Scholarship Programme.

Disclosure

E.L. Brandie: None. G.T. Jones: None.

P263 Autoantibodies in ankylosing spondylitis: a systematic literature review

Background/Aims

Ankylosing spondylitis (AS) is a chronic inflammatory arthritis leading to long term disability. It is frequently diagnosed late when irreversible damage has already occurred. Unlike most autoimmune rheumatological diseases, there are no known autoantibodies associated with AS; this can confound the diagnostic challenge as diagnosis depends not only on symptoms but on finding evidence of active inflammation at the time of assessment or damage from previously active disease. Our aim was to determine the extent to which autoantibodies may be pathognomonic of AS.

Methods

A systematic literature review was conducted to identify all articles reporting on autoantibodies in AS. The protocol was preregistered on PROSPERO. Articles were screened and reviewed independently by two reviewers. Disagreements were solved by consensus. Data were extracted and the MINORS (Methodological Index for Non-Randomised Studies) tool was used to assess and compare the quality of the studies. Data were pooled in a narrative synthesis.

Results

743 papers were identified after removal of duplicates. Following review of abstracts, 31 full text articles were assessed for eligibility and 18 were excluded, leaving 13 studies to be included in the final systematic review. 12 articles looked at 14 biomarkers; one article looked at 2 high density nucleic acid protein arrays expressing 3,498 proteins. Samples sizes were small and the papers were found to be of modest quality. AS patients showed a wide-ranging autoantibody response across studies. One study found that 60% of autoantibodies detected were found only in the AS cohort versus the rheumatoid arthritis cohort and heathy controls. Antibodies against HLA-B27, pANCA, CD74, OmpC, collagens, PPM1A, noggin, sclerostin, Klebsiella pneumoniae and Breg cells were found more commonly in AS patients than in controls (both healthy controls and those with other autoimmune diseases). Antibodies to human tTG and anti DFS70 were not found to be associated with AS and there was conflicting evidence regarding the association of antibodies to the cell-wall mannan of Saccharomyces cerevisiae (ASCA) in AS from different papers.

Conclusion

Although many autoantibodies have been found among persons with AS, there is currently no evidence that any are specifically and independently associated with the disease. We therefore conclude that as yet no autoantibodies can be considered to be pathognomonic for AS. However, some autoantibodies may be clinically significant and combined with other biomarkers, such as HLA-B27, may prove fruitful in reducing the delay to diagnosis. Further work should seek to explore other avenues, in particular autoantibodies in closely related diseases, such as inflammatory bowel disease, to try to determine autoantibodies that may aid in the earlier diagnosis of this chronic disease.

Disclosure

E.J. Davies: None. G.T. Jones: None. R. Sengupta: Honoraria; Received grants, honoraria, and expenses for attendance at advisory board meetings or conferences and for giving lectures from AbbVie, Biogen, Celgene, Lilly, MSD, Novartis, Roche and UCB. Grants/research support; Received grants, honoraria, and expenses for attendance at advisory board meetings or conferences and for giving lectures from AbbVie, Biogen, Celgene, Lilly, MSD, Novartis, Roche and UCB.

P262 The occurrence and characteristics of severe pain in patients with axial spondyloarthritis

Background/Aims

Pharmacological management of axial spondylarthritis (axSpA) seeks to control inflammation. Even if successful, available evidence suggests that many patients continue to experience pain. The aim of the current study was to determine the prevalence and characteristics of severe pain among persons with axSpA.

Methods

The Scotland Registry for Ankylosing Spondylitis (SIRAS) collected clinical and patient-reported data from adults seen in secondary care in Scotland with a clinical diagnosis of ankylosing spondylitis. Questionnaires asked about severe pain (high pain intensity; high pain interference; and extreme/unbearable pain), lifestyle, and various aspects of health. The relationship between severe pain and clinical/patient-reported factors was assessed using logistic regression.

Results

929 participants had pain data available (73% male; median symptom duration 20yrs). High pain intensity and pain interference were more common (57% and 42%) than extreme/unbearable pain (11%). Prevalence did not differ with age, although women were less likely to report severe pain than men (Odds Ratios (ORs) 0.56-0.61) as were those with longer duration of education, and those from more affluent areas. The odds of severe pain increased with every 1 unit increase in BASFI (ORs 1.44-1.56). Strong associations were also seen with disease activity, spinal mobility, fatigue, poor sleep, and worse quality of life.

Conclusion

In axSpA, severe pain is common, with a clear socio-economic gradient and major impact on quality of life. Rheumatologists need to be aware of the large unmet need in terms of pain management in this patient group with around 1 in 9 patients reporting extreme/unbearable pain.

Disclosure

G.T. Jones: Grants/research support; Research grant income for biologics registers in axSpA and PsA from the British Society for Rheumatology. The Society receives income from AbbVie, Pfizer, UCB and Amgen to support these registers, current analysis funded by GlaxoSmithKline who were provided with a copy of the results prior to submission. O. Rotariu: None. L.E. Dean: None. A.G. MacDonald: None. G.J. Macfarlane: Grants/research support; Research grant income for biologics registers in axSpA and PsA from the British Society for Rheumatology. The Society receives income from AbbVie, Pfizer, UCB and Amgen to support these registers, current analysis was funded by GlaxoSmithKline who were provided with a copy of the manuscript prior to submission.

Enabling work participation for people with musculoskeletal conditions: lessons from work changes imposed by COVID-19: a mixed-method study

OBJECTIVES

To understand what we can learn from the impact of the COVID-19 pandemic and lockdown about what enables work participation for people with inflammatory arthritis and chronic pain conditions.

DESIGN

Qualitative interviews embedded within an observational questionnaire study of individuals with musculoskeletal (MSK) conditions.

SETTING

UK primary care (general practices), and secondary care-based rheumatology services.

PARTICIPANTS

Individuals with axial spondyloarthritis, psoriatic arthritis and MSK pain from three established cohorts completed an online/paper-based questionnaire (July-December 2020). A subset of respondents were selected for semistructured interviews.

PRIMARY AND SECONDARY OUTCOME MEASURES

The survey quantified the effects of lockdown on work circumstances. Qualitative interviews explored the impacts of these changes and the advantages and disadvantages of changes in work circumstances.

RESULTS

491 people (52% female, median age 49 years) who were employed at the time of lockdown responded to the questionnaire. The qualitative analysis included 157 free-text comments on work from the questionnaire and data collected within 18 interviews.Participants reported impacts on mental and physical health, and significant financial anxieties. The impact of work changes varied depending on individual and home circumstances. Some felt forced to ignore advice to shield and continue working. The flexibility offered by home working and changes in commuting enabled greater physical activity for some, while others missed the exercise normally undertaken as part of their commute. Others reported a constant need to be 'present' online, which heightened anxiety and worsened MSK symptoms.

CONCLUSION

Lockdown showed that flexible working arrangements, which consider the positive and negative aspects of commuting, posture, movement, and work environment matter for work participation, and can have wider benefits in terms of health and well-being for those with long-term MSK conditions. Incorporating these into new models of work will help make the workplace more equitable and inclusive for people with long-term MSK conditions.

Lessons from experiences of accessing healthcare during the pandemic for remobilising rheumatology services: a national mixed methods study

Objectives

To understand the impact of the COVID-19 pandemic on access to healthcare services for patients with inflammatory and non-inflammatory MSK conditions.

Methods

Three established cohorts which included individuals with axial spondyloarthritis, psoriatic arthritis, and musculoskeletal pain completed a questionnaire between July and December 2020. In parallel, a subset of individuals participated in semi-structured interviews.

Results

1054 people (45% female, median age 59 years) were included in the quantitative analyses. Qualitative data included 447 free-text questionnaire responses and 23 interviews. 57% respondents had tried to access care since the start of UK national lockdown. Over a quarter reported being unable to book any type of healthcare appointment. GP appointments were less likely to be delayed or cancelled compared with hospital appointments. Younger age, unemployment/health-related retirement, DMARD therapy, anxiety or depression and being extremely clinically vulnerable was associated with a greater likelihood of attempting to access healthcare. People not in work, those reporting anxiety or depression and poorer quality of life were less likely to be satisfied with remotely-delivered healthcare. Participants valued clear, timely and transparent care pathways across primary care and specialist services. Whilst remote consultations were convenient for some, in-person appointments enabled physical assessment and facilitated development and maintenance of clinical relationships with care providers.

Conclusions

We have identified patient factors that predict access to and satisfaction with care, and aspects of care that patients value. This is important to inform remobilisation of rheumatology services to better meet the needs of patients.

European bio-naïve spondyloarthritis patients initiating TNFi: Time trends in baseline characteristics, treatment retention and response

OBJECTIVES

To investigate time trends in baseline characteristics and retention, remission and response rates in bio-naïve axial spondyloarthritis (axSpA) and psoriatic arthritis (PsA) patients initiating tumour necrosis factor inhibitor (TNFi) treatment.

METHODS

Prospectively collected data on bio-naïve axSpA and PsA patients from routine care in 15 European countries were pooled. Three cohorts were defined according to year of TNFi-initiation: A (1999-2008), B (2009-2014) and C (2015-2018). Retention, remission and response rates were assessed at 6, 12 and 24 months.

RESULTS

In total, 27 149 axSpA and 17 446 PsA patients were included.Cohort A patients had longer disease duration compared with B and C. In axSpA, cohort A had the largest proportion of male and HLA-B27 positive patients. In PsA, baseline disease activity was highest in cohort A.Retention rates in axSpA/PsA were highest in cohort A and differed only slightly between B and C.For all cohorts, disease activity decreased markedly from 0 to 6 months. In axSpA, disease activity at 24 months was highest in cohort A, where also remission and response rates were lowest. In PsA, remission rates at 6 and 12 months tended to be lowest in cohort A. Response rates were at all time points comparable across cohorts, and less between-cohort disease activity differences were seen at 24 months.

CONCLUSION

Our findings indicate that over the past decades, clinicians have implemented more aggressive treatment strategies in spondyloarthritis. This was illustrated by shorter disease duration at treatment initiation, decreased retention rates and higher remission rates during recent years.

Depression and anxiety symptoms at TNF inhibitor initiation are associated with impaired treatment response in axial spondyloarthritis

OBJECTIVES

Depression and anxiety are associated with more severe disease in cross-sectional studies of axial spondyloarthritis (axSpA). We examined the association between baseline symptoms of depression or anxiety and response to TNF inhibitors (TNFi) in axSpA.

METHODS

Biologic naïve participants from a national axSpA register completed the Hospital Anxiety and Depression Scale (HADS) before initiating TNFi. Symptoms of anxiety and depression were each categorized as moderate-severe (≥11), mild (8-10) and 'none' (≤7), and compared against change in disease indices [BASDAI and AS Disease Activity Score (ASDAS)] over time and time to treatment discontinuation using marginal structural models. Inverse-probability weights balanced baseline age, gender, BMI, deprivation, education and baseline values of respective disease indices.

RESULTS

Of the 742 participants (67% male, mean age 45 years), 176 (24%) had moderate-severe and 26% mild depression; 295 (40%) had moderate-severe and 23% mild anxiety. Baseline disease activity was higher in higher HADS symptom categories for both depression and anxiety. Participants with moderate-severe depression had significantly poorer response compared with those with 'none' throughout follow-up. At 6 months, the difference was approximately 2.2 BASDAI and 0.8 ASDAS units after balancing their baseline values. Equivalent comparisons for anxiety were 1.7 BASDAI and 0.7 ASDAS units. Treatment discontinuation was 1.59-fold higher (hazard ratio 95% CI: 1.12, 2.26) in participants with moderate-severe anxiety compared with 'none'.

CONCLUSIONS

Symptoms of depression and anxiety at TNFi initiation are associated with poorer treatment outcomes. Targeted interventions to optimize mental health have potential to substantially improve treatment response and persistence.

Comorbidity and response to TNF inhibitors in axial spondyloarthritis: longitudinal analysis of the BSRBR-AS

Objective

Comorbidities influence disease assessment in axial spondyloarthritis (axSpA), but their association with response to TNF inhibitors (TNFi) is unclear. We examined associations between comorbidity history at TNFi initiation and: (i) change in disease indices over time; (ii) binary response definitions; and (iii) time to treatment discontinuation.

Methods

We studied participants starting their first TNFi from a national axSpA register. Comorbidity categories were created from 14 physician-diagnosed conditions and compared against: change in disease indices over time using linear mixed effects models; BASDAI50/2 (50% or 2-unit reduction) and BASDAI < 4 at 6 months using logistic models; and time to treatment discontinuation using Cox models. Models were adjusted for age, gender, BMI, deprivation and education.

Results

In total, 994 were eligible for analysis (68% male, mean age 45 years); 21% had one comorbidity and 11% had ≥2. Baseline disease severity was higher in those with comorbidities across all indices, but absolute improvement over time was comparable for BASDAI and spinal pain. Participants with ≥2 comorbidities had smaller absolute improvement in BASFI and quality of life. This group also had numerically reduced odds of achieving BASDAI50/2 [odds ratio (OR) 0.81; 95% CI: 0.45, 1.45] and BASDAI < 4 (OR 0.57; 95% CI: 0.32, 1.04). Treatment discontinuation was increased in those with two comorbidities [hazard ratio (HR) 1.32; 95% CI: 0.88, 2.00] and ≥3 comorbidities (HR 2.18; 95% CI: 1.20, 3.93) compared with none.

Conclusions

Participants with multiple comorbidities had poorer treatment outcomes, particularly increased treatment discontinuation and poorer improvements in function and quality of life. These results inform clinicians and educate patients about response to the first TNFi given comorbidity burden.

Association between comorbidities and disease activity in axial spondyloarthritis: results from the BSRBR-AS

Objective

Whether comorbidities influence disease activity assessment in axial SpA (axSpA) is unclear. Comorbidities inflate DAS28 in rheumatoid arthritis through the patient global score. We examined whether axSpA disease activity measures are differentially affected, and whether comorbidities inflate the AS disease activity score (ASDAS) through the patient global component.

Methods

We used baseline data from the British Society for Rheumatology Biologics Register for AS, including 14 physician diagnosed comorbidities. Linear models were used to compare disease activity (BASDAI, spinal pain, ASDAS) and ESR/CRP according to comorbidity count, adjusted for age, gender, BMI, smoking, socioeconomic status, and education. The same models were used to examine whether the patient global score was associated with comorbidities, additionally adjusting for other ASDAS components.

Results

The number of participants eligible for analysis was 2043 (67% male, mean age 49 years); 44% had at least one comorbidity. Each additional comorbidity was associated with higher BASDAI by 0.40 units (95% CI: 0.27, 0.52) and spinal pain by 0.53 (95% CI: 0.37, 0.68). Effect size for ASDAS (0.09 units; 95% CI: 0.03, 0.15) was not clinically significant. ESR and CRP were not associated with comorbidity count. Depression, heart failure and peptic ulcer were consistently associated with higher disease activity measures, but not CRP/ESR. Patient global was associated with comorbidity count, but not independently of other ASDAS components (P = 0.75).

Conclusion

Comorbidities were associated with higher patient reported disease activity in axSpA. Clinicians should be mindful of the potential impact of comorbidities on patient reported outcome measures and consider additionally collecting ASDAS when comorbidities are present.

Effectiveness and treatment retention of TNF inhibitors when used as monotherapy versus comedication with csDMARDs in 15 332 patients with psoriatic arthritis. Data from the EuroSpA collaboration

Background

Comedication with conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) during treatment with tumour necrosis factor inhibitors (TNFi) is extensively used in psoriatic arthritis (PsA), although the additive benefit remains unclear. We aimed to compare treatment outcomes in patients with PsA treated with TNFi and csDMARD comedication versus TNFi monotherapy.

Methods

Patients with PsA from 13 European countries who initiated a first TNFi in 2006–2017 were included. Country-specific comparisons of 1 year TNFi retention were performed by csDMARD comedication status, together with HRs for TNFi discontinuation (comedication vs monotherapy), adjusted for age, sex, calendar year, disease duration and Disease Activity Score with 28 joints (DAS28). Adjusted ORs of clinical remission (based on DAS28) at 12 months were calculated. Between-country heterogeneity was assessed using random-effect meta-analyses, combined results were presented when heterogeneity was not significant. Secondary analyses stratified according to TNFi subtype (adalimumab/infliximab/etanercept) and restricted to methotrexate as comedication were performed.

Results

In total, 15 332 patients were included (62% comedication, 38% monotherapy). TNFi retention varied across countries, with significant heterogeneity precluding a combined estimate. Comedication was associated with better remission rates, pooled OR 1.25 (1.12–1.41). Methotrexate comedication was associated with improved remission for adalimumab (OR 1.45 (1.23–1.72)) and infliximab (OR 1.55 (1.21–1.98)) and improved retention for infliximab. No effect of comedication was demonstrated for etanercept.

Conclusion

This large observational study suggests that, as used in clinical practice, csDMARD and TNFi comedication are associated with improved remission rates, and specifically, comedication with methotrexate increases remission rates for both adalimumab and infliximab.

The BSR-PsA: study protocol for the British Society for Rheumatology psoriatic arthritis register

BACKGROUND

Psoriatic arthritis (PsA) presents a unique clinical challenge. Affecting joints, skin, nails, and other organs, it is associated with various comorbidities and has a significant impact on quality of life, social participation and working life. While biologic and other targeted synthetic disease modifying anti-rheumatic drugs (bDMARDs and tsDMARDs) have revolutionised therapy, questions remain about the long-term safety of these agents, and their effectiveness and cost-effectiveness in the real-world clinical setting.

METHODS/DESIGN

The British Society for Rheumatology Psoriatic Arthritis Register (BSR-PsA) is a prospective registry of patients with PsA, recruited from across Great Britain, who are (a) commencing a bDMARD/tsDMARD; or (b) naïve to all bDMARDs/tsDMARDs. Ethical approval was given by the NHS West of Scotland Research Ethics Committee 3 (reference: 18/WS/0126). Clinical data are extracted from participants' medical records, including symptom onset and diagnosis, joint, skin and nail symptoms, dactylitis and enthesitis. Physical measurements (height, weight and 66/68 joint counts) and a detailed drug history are taken. Participants are also asked to complete questionnaires comprising instruments relating to general health and quality of life, axial disease, sleep and fatigue, impact of disease, functional status, mental health, other symptoms, and occupational status. The study duration is 5 years in the first instance, and all participants are followed up annually until the end of the study. Participants commencing a bDMARD/tsDMARD are also followed up three and six months after the start of therapy. Disease activity, including C-reactive protein, is assessed at each visit; and participants from some centres are invited to donate blood and urine samples for the creation of a biobank.

DISCUSSION

Complementing data from randomised trials, results from this study will contribute to the evidence base underpinning the clinical management of psoriatic arthritis. Various analyses will determine the effectiveness and safety of bDMARDs/tsDMARDs in the real-world, will examine the clinical and biological predictors of treatment response, and will provide real-world data on the cost-effectiveness of these therapies, as well as providing informative data important to patients such as quality of life and occupational outcomes.

TRIAL REGISTRATION

The full study protocol is registered on the Open Science Framework ( https://osf.io/jzs8n ).

The effect of COVID19 public health restrictions on the health of people with musculoskeletal conditions and symptoms: the CONTAIN study

OBJECTIVE

To quantify the change in quality of life, disease-specific indicators, health, and lifestyle before and during the COVID19 pandemic amongst people with musculoskeletal diagnoses and symptoms.

METHODS

We undertook an additional follow-up of two existing UK registers involving people with axial spondyloarthritis (axSpA) or psoriatic arthritis (PsA) and participants in a trial in the UK who had regional pain and were identified at high risk of developing chronic widespread pain. Participants completed the study questionnaire between July and December 2020, throughout which time there were public health restrictions in place.

RESULTS

1054 people took part in the study (596 axSpA, 162 PsA, 296 regional pain). In comparison to their previous (pre-pandemic) assessment, there was an age-adjusted significant, small, decrease in quality of life measured by EQ-5D (-0.020 95% CI (-0.030, -0.009)) overall and across all population groups examined. This was primarily related to poorer mental health and pain. There was a small increase in fibromyalgia symptoms, but a small decrease in sleep problems. There was a small deterioration in axSpA disease activity, and disease-specific quality of life and anxiety in PsA participants. Predictors of poor quality of life were similar pre- and during the pandemic. The effect of lockdown on activity differed according to age, gender, and deprivation.

CONCLUSION

Important lessons include focussing on addressing anxiety and providing enhanced support for self-management in the absence of normal health care being available, and awareness that all population groups are likely to be affected.

Predictors of extra-articular manifestations in axial spondyloarthritis and their influence on TNF-inhibitor prescribing patterns: results from the British Society for Rheumatology Biologics Register in Ankylosing Spondylitis

OBJECTIVES

Extra-articular manifestations (EAMs) are important systemic features of axial spondyloarthritis (axSpA), which may influence the choice of tumour necrosis factor-inhibitor (TNFi). We examined the cumulative incidence and predictors of EAMs and the influence of these on first TNFi choice in a 'real-world' cohort of patients with axSpA.

METHODS

Clinical and patient-reported outcomes of 2420 patients with axSpA from 83 centres were collected by the British Society for Rheumatology Biologics Register in Ankylosing Spondylitis. Lifestyle factors for EAMs (acute anterior uveitis (AAU), inflammatory bowel diseases (IBD), psoriasis) were compared with those without EAMs. Also, the association between pretreatment EAMs and choice of first TNFi (adalimumab, etanercept, certolizumab) was analysed.

RESULTS

AAU was directly associated with human leukocyte antigen (HLA)-B27 (incidence rate ratio (IRR) 1.95, 95% CI 1.40 to 2.73) and inversely associated with ever-smoking (IRR=0.71, 95% CI 0.55 to 0.92). For both psoriasis and IBD, there was an inverse relationship with HLA-B27 (IRR 0.54, 95% CI 0.36 to 0.79 and IRR 0.63, 95% CI 0.43 to 0.91, respectively). A diagnosis of either AAU (OR 3.79, 95% CI 2.11 to 6.80) or IBD (OR 5.50, 95% CI 2.09 to 14.46) was associated with preference for adalimumab versus others. In contrast, a diagnosis of either AAU (OR 0.14, 95% CI 0.06 to 0.33) or IBD (OR 0.17, 95% CI 0.05 to 0.57) was associated with less preference for etanercept over other TNFi.

CONCLUSION

The higher occurrence of AAU and lower occurrence of psoriasis and IBD in HLA-B27-positive patients with axSpA are consistent with current pathophysiology. Patients with previous AAU and IBD are more likely to be prescribed adalimumab and less likely to receive etanercept, consistent with the superior efficacy of monoclonal TNFi for these indications. Future work will determine whether EAMs influence TNFi survival, or effectiveness, and whether this varies between agents.

Polygenic Risk Scores have high diagnostic capacity in ankylosing spondylitis

Objective

We sought to test the hypothesis that Polygenic Risk Scores (PRSs) have strong capacity to discriminate cases of ankylosing spondylitis (AS) from healthy controls and individuals in the community with chronic back pain.

Methods

PRSs were developed and validated in individuals of European and East Asian ethnicity, using data from genome-wide association studies in 15 585 AS cases and 20 452 controls. The discriminatory values of PRSs in these populations were compared with other widely used diagnostic tests, including C-reactive protein (CRP), HLA-B27 and sacroiliac MRI.

Results

In people of European descent, PRS had high discriminatory capacity with area under the curve (AUC) in receiver operator characteristic analysis of 0.924. This was significantly better than for HLA-B27 testing alone (AUC=0.869), MRI (AUC=0.885) or C-reactive protein (AUC=0.700). PRS developed and validated in individuals of East Asian descent performed similarly (AUC=0.948). Assuming a prior probability of AS of 10% such as in patients with chronic back pain under 45 years of age, compared with HLA-B27 testing alone, PRS provides higher positive values for 35% of patients and negative predictive values for 67.5% of patients. For PRS, in people of European descent, the maximum positive predictive value was 78.2% and negative predictive value was 100%, whereas for HLA-B27, these values were 51.9% and 97.9%, respectively.

Conclusions

PRS have higher discriminatory capacity for AS than CRP, sacroiliac MRI or HLA-B27 status alone. For optimal performance, PRS should be developed for use in the specific ethnic groups to which they are to be applied.

Epidemiology of chronic pain in children and adolescents: a protocol for a systematic review update

INTRODUCTION

Chronic pain, defined as persistent or recurring pain or pain lasting longer than 3 months, is a common childhood problem and can profoundly impact children's physical, psychological and social functioning. The last comprehensive systematic review estimating the prevalence of chronic pain in children and adolescents was published in 2011. Since then, the literature on paediatric chronic pain has grown substantially. This manuscript outlines a protocol for an updated systematic review to provide updated estimates of the prevalence of various forms of chronic pain in children and adolescence. The review will also examine the relationship between sociodemographic and psychosocial factors related to chronic pain prevalence.

METHODS AND ANALYSIS

This review will follow Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We will search EMBASE, PubMed, CINAHL and PsycINFO for observational studies published in English between 2009 and 2020 reporting population-based estimates of chronic non-disease-related pain prevalence in children or adolescents (age ≤19 years). Two independent reviewers will screen the titles and abstracts retrieved from the search based on predefined eligibility criteria. The full texts of relevant studies will then be assessed by two reviewers. Studies meeting inclusion criteria will be categorised according to the type of pain investigated: headache only, abdominal pain only, back pain only, musculoskeletal pain, combined pain, general pain and other pain. Data will be extracted using customised forms and studies will be assessed for risk of bias using a 10-item tool developed by Hoy et al (2012). A narrative synthesis will summarise the prevalence estimates of paediatric chronic pain and associated sociodemographic and psychosocial correlates. Meta-analyses and meta-regressions will be performed if the data permit.

ETHICS AND DISSEMINATION

Ethical approval is not required. Findings will be disseminated through publication in an academic journal, presentations at conferences and in various media.

PROSPERO REGISTRATION NUMBER

CRD42020198690.

Maintaining musculoskeletal health using a behavioural therapy approach: a population-based randomised controlled trial (the MAmMOTH Study)

Objective

Cognitive–behavioural therapy (CBT) has been shown to be effective in the management of chronic widespread pain (CWP); we now test whether it can prevent onset among adults at high risk.

Methods

A population-based randomised controlled prevention trial, with recruitment through UK general practices. A mailed screening questionnaire identified adults at high risk of CWP. Participants received either usual care (UC) or a short course of telephone CBT (tCBT). The primary outcome was CWP onset at 12 months assessed by mailed questionnaire. There were seven secondary outcomes including quality of life (EuroQol Questionnaire-five dimensions-five levels/EQ-5D-5L) used as part of a health economic assessment.

Results

996 participants were randomised and included in the intention-to-treat analysis of which 825 provided primary outcome data. The median age of participants was 59 years; 59% were women. At 12 months there was no difference in the onset of CWP (tCBT: 18.0% vs UC: 17.5%; OR 1.05; 95% CI 0.75 to 1.48). Participants who received tCBT were more likely to report better quality of life (EQ-5D-5L utility score mean difference 0.024 (95% CI 0.009 to 0.040)); and had 0.023 (95% CI 0.007 to 0.039) more quality-adjusted life-years at an additional cost of £42.30 (95% CI −£451.19 to £597.90), yielding an incremental cost-effectiveness ratio of £1828. Most secondary outcomes showed significant benefit for the intervention.

Conclusions

A short course of tCBT did not prevent onset of CWP in adults at high risk, but improved quality of life and was cost-effective. A low-cost, short-duration intervention benefits persons at risk of CWP.

Trial registration number

ClinicalTrials.gov Registry (NCT02668003).

Similar biologic drug response regardless of radiographic status in axial spondyloarthritis: data from the BSRBR-AS registry

OBJECTIVES

To describe the baseline characteristics, bDMARD response and drug survival of axSpA patients in the British Society for Rheumatology Biologics Register in Ankylosing Spondylitis (BSRBR-AS) according to radiographic status.

METHODS

BSRBR-AS is a national prospective cohort including axSpA participants classified according to the ASAS criteria. In this analysis, baseline data of patients starting bDMARDs were compared. Ankylosing Spondylitis Disease Activity Scores (ASDAS) for low disease status, clinically important improvement (CII) and major improvement (MI) at one year were used to assess treatment response. Cox proportional hazard analysis was performed after adjusting for clinically relevant cofounders.

RESULTS

1,145 axSpA patients were included. Higher male prevalence, older age and longer disease duration was seen in the r-axSpA subgroup. Based on a complete case analysis (290 patients), two thirds of patients achieved ASDAS low disease state at one year regardless of radiographic status (nr-axSpA: 64.2% vs r-axSpA: 66.1). No statistically significant differences were seen between the subgroups in attaining ASDAS CII (nr-axSpA: 50.7% vs r-axSpA: 44.7%) or MI (nr-axSpA: 20% vs r-axSpA: 18.7%). Drug survival probability curves were similar for both subgroups and hazard ratio for nr-axSpA/axSpA was 0.94 (95% CI 0.69-1.28) when adjusted for sex, age, baseline ASDAS-CRP, smoking status, disease duration, HLA-B27 and prescribed biologic.

CONCLUSIONS

Although there appeared to be some differences in the baseline characteristics when exploring this cohort according to radiographic status which are likely related to the natural history of the disease, the level of biologic response and drug survival was comparable between nr-axSpA and r-axSpA.

Impact of discordance between patient's and evaluator's global assessment on treatment outcomes in 14 868 patients with spondyloarthritis

OBJECTIVES

To assess the impact of 'patient's minus evaluator's global assessment of disease activity' (ΔPEG) at treatment initiation on retention and remission rates of TNF inhibitors (TNFi) in psoriatic arthritis (PsA) and axial spondyloarthritis (axSpA) patients across Europe.

METHODS

Real-life data from PsA and axSpA patients starting their first TNFi from 11 countries in the European Spondyloarthritis Research Collaboration Network were pooled. Retention rates were compared by Kaplan-Meier analyses with log-rank test and by Cox regression, and remission rates by χ2 test and by logistic regression across quartiles of baseline ΔPEG, separately in female and male PsA and axSpA patients.

RESULTS

We included 14 868 spondyloarthritis (5855 PsA, 9013 axSpA) patients. Baseline ΔPEG was negatively associated with 6/12/24-months' TNFi retention rates in female and male PsA and axSpA patients (P <0.001), with 6/12/24-months' BASDAI < 2 (P ≤0.002) and ASDAS < 1.3 (P ≤0.005) in axSpA patients, and with DAS28CRP(4)<2.6 (P ≤0.04) and DAPSA28 ≤ 4 (P ≤0.01), but not DAS28CRP(3)<2.6 (P ≥0.13) in PsA patients, with few exceptions on remission rates. Retention and remission rates were overall lower in female than male patients.

CONCLUSION

High baseline patient's compared with evaluator's global assessment was associated with lower 6/12/24-months' remission as well as retention rates of first TNFi in both PsA and axSpA patients. These results highlight the importance of discordance between patient's and evaluator's perspective on disease outcomes.

The changing states of fibromyalgia in patients with axial spondyloarthritis: results from the British Society of Rheumatology Biologics Register for Ankylosing Spondylitis

Objectives

To identify factors associated with FM development and recovery in patients with axial SpA (axSpA).

Methods

The British Society of Rheumatology Biologics Register for Ankylosing Spondylitis (BSRBR-AS) recruited patients with axSpA from 83 centres in a prospective study. FM was diagnosed using the self-reported Fibromyalgia Survey Diagnostic Criteria from 2015. Measures of axSpA disease activity and clinical findings were recorded at regular intervals. We identified predictors for FM development and recovery between yearly visits using uni- and multivariable logistic regression models.

Results

A total of 801 participants, 247 (30.8%) female, had two or more visits and were eligible for inclusion. A total of 686 participants did not have FM at baseline, of whom 45 had developed FM at follow-up, while 115 participants had FM at baseline, of whom 77 had recovered at follow-up. A high baseline BASDAI score [odds ratio (OR) 1.27 (95% CI 1.08, 1.49)] and Widespread Pain Index (WPI) [OR 1.14 (95% CI 1.02, 1.28)] were significantly associated with FM development in the final multivariable model. A low baseline BASFI score [OR 0.68 (95% CI 0.53, 0.86)] and WPI [OR 0.84 (95% CI 0.720, 0.97)] and starting a TNF inhibitor [OR 3.86 (95% CI 1.54, 9.71)] were significantly associated with FM recovery.

Conclusion

High levels of disease activity and the presence of widespread pain is associated with the development of FM in patients with axSpA, while low levels of the same variables and starting a TNF inhibitor are associated with recovery from FM. The presence of comorbid FM should be considered in patients with persistent high axSpA disease activity and widespread pain.

Genomewide Association Study of Acute Anterior Uveitis Identifies New Susceptibility Loci

Purpose

Acute anterior uveitis (AAU) is a common intraocular inflammatory disease. AAU occurs in 30% to 50% of patients with ankylosing spondylitis (AS), and both conditions are strongly associated with human leukocyte antigen (HLA)-B27, implying a shared etiology. This study aims to apply genomewide association study (GWAS) to characterize the genetic associations of AAU and their relationship to the genetics of AS.

Methods

We undertook the GWAS analyses in 2752 patients with AS with AAU (cases) and 3836 patients with AS without AAU (controls). There were 7,436,415 single-nucleotide polymorphisms (SNPs) available after SNP microarray genotyping, imputation, and quality-control filtering.

Results

We identified one locus associated with AAU at genomewide significance: rs9378248 (P = 2.69 × 10⁻⁸, odds ratio [OR] = 0.78), lying close to HLA-B. Suggestive association was observed at 11 additional loci, including previously reported AS loci ERAP1 (rs27529, P = 2.19 × 10⁻⁷, OR = 1.22) and NOS2 (rs2274894, P = 8.22 × 10⁻⁷, OR = 0.83). Multiple novel suggestive associations were also identified, including MERTK (rs10171979, P = 2.56 × 10⁻⁶, OR = 1.20), KIFAP3 (rs508063, P = 5.64 × 10⁻⁷, OR = 1.20), CLCN7 (rs67412457, P = 1.33 × 10⁻⁶, OR = 1.25), ACAA2 (rs9947182, P = 9.70 × 10⁻⁷, OR = 1.37), and 5 intergenic loci. The SNP-based heritability is approximately 0.5 for AS alone, and is much higher (approximately 0.7) for AS with AAU. Consistent with the high heritability, a genomewide polygenic risk score shows strong power in identifying individuals at high risk of either AS with AAU or AS alone.

Conclusions

We report here the first GWAS for AAU and identify new susceptibility loci. Our findings confirm the strong overlap in etiopathogenesis of AAU with AS, and also provide new insights into the genetic basis of AAU.

Role of Metrology in Axial Spondyloarthritis: Does It Provide Unique Information in Assessing Patients and Predicting Outcome? Results From the British Society for Rheumatology Biologic Register for Ankylosing Spondylitis

OBJECTIVE

To determine among patients with axial spondyloarthritis (SpA) the factors associated with decreased spinal mobility and to determine whether poor mobility is a predictor of response to anti-tumor necrosis factor (anti-TNF) therapy.

METHODS

This was a prospective UK cohort study of persons meeting Assessment of Spondylarthritis international Society (ASAS) criteria for axial SpA. At recruitment, clinical and patient-reported factors independently associated with spinal mobility (measured by the Bath Ankylosing Spondylitis Metrology Index [BASMI]) were determined. Among those commencing anti-TNF therapy, factors that were independent predictors of response were determined using ASAS criteria, quality of life, and Ankylosing Spondylitis Disease Activity Score (ASDAS) response criteria.

RESULTS

A total of 1,960 participants were eligible; 70% were male and the median age was 48 years (interquartile range [IQR] 37,59), median BASMI score 3.6 (IQR 2.2, 5.3). Factors independently associated with poor spinal mobility were poorer function, meeting radiographic criteria for AS, longer symptom duration, higher levels of inflammation (measured by C-reactive protein level), older age, male sex, not being currently employed, and lower levels of education. For 51% of participants, the measured BASMI score was within 1 of that estimated. Poorer mobility (higher BASMI score) was an independent predictor of not meeting response criteria for ASAS 20% improvement (odds ratio [OR] per increasing score 0.80 [IQR 0.66, 0.98]), ASAS 40% improvement (OR 0.69 [IQR 0.50, 0.95]), and quality of life (measured by the Ankylosing Spondylitis Quality of Life Questionnaire) (β = 0.64 [IQR 0.26, 1.02]), but was not related to meeting ASDAS response criteria.

CONCLUSION

The BASMI score was estimated moderately well by other routinely measured factors in patients with axial SpA and was an independent predictor of response to biologic therapy for some, but not all, commonly used measures. Consensus around its role in disease monitoring and clinical decisions, particularly in the likely context of face-to-face consultations becoming less frequent, remains to be established.

Quantifying and predicting the effect of anti-TNF therapy on axSpA-related fatigue: results from the BSRBR-AS registry and meta-analysis

OBJECTIVES

Effective management of axial spondyloarthritis (axSpA)-related fatigue is a major unmet clinical need. Anti-TNF therapy may reduce fatigue levels, although any effect has yet to be definitively quantified and predictors of any such improvements are unknown.

METHODS

The British Society of Rheumatology Register in Axial Spondyloarthritis (BSRBR-AS) prospectively recruited axSpA patients across the UK. Changes in fatigue levels (measured using the Chalder Fatigue Scale) >1 year were compared between those starting anti-TNF therapy at the time of recruitment and those not. Differences between treatment groups were adjusted using propensity score matching. Results were meta-analysed with the extant literature to calculate pooled estimates. Then, among those BSRBR-AS anti-TNF commencers with clinically relevant fatigue, baseline predictors of response were investigated.

RESULTS

Of the 998 BSRBR-AS recruits with complete fatigue data, 310 were anti-TNF commencers. At 1-year follow-up, the former group reported a mean fatigue change of -2.6 (95% CI -4.1, -1.9) points while the latter reported a mean worsening of fatigue by 0.2 points. Following propensity score adjustment, those commencing anti-TNF therapy reduced fatigue by 3.0 points compared with those not. Of those with significant fatigue and commencing anti-TNF, poor sleep quality at baseline predicted fatigue improvement. In the meta-analysis, including 1109 subjects, treatment with anti-TNF therapy resulted in a significant improvement in fatigue [Standardized mean difference (SMD) = 0.36, 95% CI 0.15, 1.56].

CONCLUSION

Anti-TNF therapy results in a significant but modest reduction in fatigue amongst axSpA patients, with those reporting poor sleep quality most likely to report improvement. Effective management will likely require additional approaches.

Predicting response to anti-TNFα therapy among patients with axial spondyloarthritis (axSpA): results from BSRBR-AS

OBJECTIVES

While many axSpA patients, eligible to receive anti-TNFα therapy, derive benefit when prescribed them, some patients do not. The current study aims to identify modifiable targets to improve outcome as well as non-modifiable targets that identify groups less likely to derive benefit.

METHODS

The BSRBR-AS is a prospective cohort study of axSpA patients who, at recruitment, were naïve to biologic therapy. Those in the 'biologic' sub-cohort commenced their first anti-TNFα therapy at recruitment or during follow-up. Prior to commencement, information was collected on socio-economic, clinical and patient-reported factors. Outcome was assessed according to ASAS20, ASAS40, ASDAS reduction and achieving a moderate/inactive ASDAS disease state.

RESULTS

335 participants commenced their first anti-TNFα therapy and were followed up at a median of 14 (inter-quartile range 12-17) weeks. Response varied between 33% and 52% according to criteria used. Adverse socio-economic factors, fewer years in education predicted lower likelihood of response across outcome measures as did not working full-time. Co-morbidities and poor mental health were clinical and patient-reported factors, respectively, associated with lack of response. The models, particularly those using ASDAS, were good at predicting those who did not respond (negative predictive value (NPV) 77%).

CONCLUSION

Some factors predicting non-response (such as mental health) are modifiable but many (such as social/economic factors) are not modifiable in clinic. They do, however, identify patients who are unlikely to benefit from biologic therapy alone. Priority should focus on how these patients receive the benefits that many derive from such therapies.

The prevalence of fibromyalgia in axial spondyloarthritis

Comorbid fibromyalgia, in axial spondyloarthritis (axSpA) has been shown to influence disease activity and function, and quality of life. Although several papers exist, there is no comprehensive and robust systematic review to determine the prevalence of fibromyalgia in this patient group. Thus, the aim of the current study was to provide a definitive estimate of prevalence of fibromyalgia in axSpA, and in axSpA sub-classifications. A systematic literature search was conducted in Ovid MEDLINE, EMBASE, Evidence Based Medicine (EBM), and Cochrane Library, updated to April 2020, combining keywords and relevant MeSH headings, to identify papers reporting the prevalence of fibromyalgia in axSpA, or data from which this could be computed. This was then combined in a meta-analysis with data from the Scotland Registry for Ankylosing Spondylitis (SIRAS), a national axSpA register in Scotland. Data was pooled using random or fixed effects models where heterogeneity was greater or lesser than 75%. From 3401 manuscripts initially identified, 15 papers were included in the final review, plus SIRAS, giving data from 16 separate sources. The prevalence of fibromyalgia, among a total of 5214 patients, was 16.4% (95% CI 12.3–20.5%). Prevalence varied with axSpA sub-classification: ankylosing spondylitis: 13.8% (9.1–18.6%); MRI positive non-radiographic axSpA 20.3% (6.5–34.1%); and ‘clinical’ disease: 11.1% (6.0–16.2%). Overall, around 1 in 6 patients with axSpA also meet criteria for fibromyalgia. While estimates from individual studies vary, comorbid fibromyalgia represents a considerable burden across all sub-classifications of axSpA. This emphasises that focusing management solely on inflammatory disease in this patient group is unlikely to yield optimal improvements in quality of life.

Real-world evidence of TNF inhibition in axial spondyloarthritis: can we generalise the results from clinical trials?

Management guidelines assume that results from clinical trials can be generalised, although seldom is data available to test this assumption. We aimed to determine the proportion of patients commencing tumour necrosis factor inhibition (TNFi) who would have been eligible for relevant clinical trials, and whether treatment response differs between these groups and the trials themselves. The British Society for Rheumatology Biologics Register for Ankylosing Spondylitis (BSRBR-AS) recruited a real-world cohort of TNFi-naïve spondyloarthritis patients with data collection from clinical records and patient questionnaires. Participant characteristics were extracted from trials identified from a recent Health Technology Assessment of TNFi for ankylosing spondylitis/non-radiographic axial spondyloarthritis. Descriptive statistics were used to determine the differences, including treatment response, between BSRBR-AS participants who would/would not have been eligible for the clinical trials and with trial participants. Among 2420 BSRBR-AS participants, those commencing TNFi (34%) had shorter symptom duration (15 vs 22 years) but more active disease (Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) 6.4 vs 4.0; Bath Ankylosing Spondylitis Disease Functional Index (BASFI) 6.2 vs 3.8). Of those commencing TNFi, 41% met eligibility criteria for ≥1 of fourteen relevant trials; they reported higher disease activity (BASDAI 6.9 vs 6.1) and poorer function (BASFI 6.6 vs 6.0). 61.7% of trial participants reported a positive treatment response, vs 51.3% of BSRBR-AS patients (difference: 10.4%; 95% CI 4.4% to 16.5%). Potential eligibility for trials did not influence treatment response (difference 2.0%; -9.4% to 13.4%). Fewer patients in the real world respond to TNFi than is reported in the trial literature. This has important implications for the generalisability of trial results, and the cost-effectiveness of TNFi agents.

O15 Maintaining musculoskeletal health: a randomised controlled trial of cognitive behaviour therapy among people at high risk of developing chronic widespread pain

Background

Cognitive behaviour therapy (CBT) is effective in the management of fibromyalgia (and its characteristic feature chronic widespread pain (CWP). CBT is recommended in all recent major fibromyalgia management guidelines. From large-scale epidemiological studies, prediction models are available which identify groups at high-risk of developing CWP. We now test whether it is possible to prevent onset of CWP and/or change factors associated with its onset.

Methods

A randomised controlled trial of CBT delivered by telephone plus usual care (tCBT) was tested against usual care alone (UC). Eligible adults aged at least 25 years were identified by a survey of persons registered with sixteen general practices across Scotland. Respondents reporting regional pain (not CWP) for which they had recently consulted their GP and at least 2 items from a previously validated ‘high risk’ profile (Somatic Symptom Scale, Sleep Problem Scale, Illness Behaviour Scale) were invited to participate. tCBT was delivered across 6 sessions over 8 weeks with booster sessions 3 and 6 months after treatment start. Primary outcome was CWP at 12 months. Secondary outcomes were risk profile measures: fatigue (Chalder Fatigue Scale), Patient Global Impression of Change (PGIC: 7 categories), psychological distress (General Health Questionnaire) and quality of life (EQ-5D-5L) also at 12 months. Analysis used logistic, ordinal logistic or linear regression depending on outcome variable type; expressed as an effect size with 95% confidence interval.

Results

1,002 people were randomised, with equal numbers assigned to each arm of the trial: 59% of participants were female, with a median age of 59 (range 25-91) years. 66% of tCBT participants completed treatment and 83% of all participants provided follow-up data at 12 months. There was no difference in the proportion with CWP at 12 months (tCBT 18.0% v. UC 17.5%). There were improvements (all favouring tCBT) in Illness Behaviour Score (mean difference (md) -0.83; -1.55,-0.11), Sleep Problem Scale (md -0.90; -1.45,-0.36), psychological distress (Odds Ratio (OR) per category 0.65; 0.50, 0.85), EQ-5D-5L (md 0.024; 0.009, 0.039), Chalder Fatigue Scale (md -1.05; -1.66,-0.44) and PGIC (OR per category 0.51;0.39,0.67). Specifically 30.2% of those receiving tCBT reported their health as much or very much better, compared to 17.3% of those receiving UC.

Conclusion

This first-ever large-scale trial of prevention, aimed at persons at high risk, has shown tCBT does not change the likelihood of CWP onset but does improve the underlying risk profile for developing the condition as well as improving distress , fatigue and quality of life. Those receiving tCBT were, 12 months later, significantly more like to consider their health was better. This trial provides evidence for extending the group of people considered to benefit from CBT.

Disclosures

G.J. Macfarlane None. M. Beasley None. N. Scott None. P. McNamee None. J. McBeth None. G. Prescott None. G.T. Jones None. P. Hannaford None. N. Basu None. P. Keeley None. K. Lovell None.

The epidemiology of regular opioid use and its association with mortality: Prospective cohort study of 466 486 UK biobank participants

BACKGROUND

Opioids have, at most, small benefits for non-cancer pain in the medium and long-term but there is good evidence that they cause harm. The current study describes the characteristics and clinical status of people taking regular opioids in Great Britain and determines whether use is associated with mortality risk.

METHODS

An analysis of participants in UK Biobank, a prospective population-based study. At recruitment (2006-10) participants reported medicines which they regularly used in addition to lifestyle and health-related factors. Information was available on deaths until October 2016.

FINDINGS

There were 466 486 participants (54% women) aged 40-69 years and without a prior history of cancer of whom 5.5% were regularly using opioids. Use increased with age-group, was more common in females (6.3% v. 4.6%) and 87% of persons using them reported chronic pain. The highest rates of use (~1 in 9) were in people with low household income, who left school <16 years and lived in areas with high deprivation. Amongst 15,032 people who could not work because of ill-health, 1 in 3 were regularly taking opioids. Regular users reported insomnia (88.7%), a recent major recent life event (57.3%) and were much more likely than non-users to rate their health as poor (RR 5.5, 99% CI (4.9, 6.1)). Those taking weak (4.2% of participants) or strong (1.4%) opioids were more likely to die during follow-up (6.9% and 9.1% respectively v. 3.3% in non-users) an excess which remained after adjustment for demographic, socio-economic, health and lifestyle factors (MRR 1.18 99% CI (1.06, 1.32) and 1.20 99% CI (1.01, 1.43)) respectively.

INTERPRETATION

Regular use of opioids is common in Great Britain, particularly in groups of low socio-economic status. Most users still report chronic pain, poor health generally and are at increased risk of premature death although it is not established that this relationship is causal.

FUNDING

There were no external sources of funding obtained for the current analyses.

P244 Determining factors related to poor quality of life in patients with axSpA: results from the British Society for Rheumatology Biologics Register

Background

The aim when treating people with axial spondyloarthropathies (axSpA) is to maintain/improve their Quality of Life (QoL), traditionally through reducing disease activity. Previously, the Scotland Registry for Ankylosing Spondylitis (SIRAS) demonstrated, however, that although important, disease activity may not be the only factor influencing QoL. Indeed, function was a better predictor, with fatigue, chronic widespread pain and spinal mobility also important. The aim of the current study was to validate the previous findings in a large nationwide population, and determine if other factors, not collected in the previous study (such as mood and sleep) are also important.

Methods

The British Society for Rheumatology Biologics Register in Ankylosing Spondylitis (BSRBR-AS) is a prospective cohort of axSpA patients from 83 secondary care centres across Great Britain. Clinical data was collected during routine clinic visits and questionnaires provided patient reported outcomes including: the Ankylosing Spondylitis QoL questionnaire (ASQoL: scored 0 (best) to 18 (worst)), the Bath AS indices for disease & physical activity ((BASDAI/BASFI: scored 0 (best) - 10 (worst)), sleep disturbance (Jenkins: 0 (best) - 20 (worst)), depression (hospital anxiety & depression scales: scored 0 (best) - 21 (worst)) and the modification of the 2010 fibromyalgia criteria (widespread pain index (WPI): scored 0 (best) - 19 (worst) & symptom severity score (SSS): 0 (best) -12 (worst)). Using data collected at BSRBR-AS registration, multivariate linear regression models, predicting ASQoL, were used to validate the previous SIRAS model. Additionally, a de-novo forward stepwise model was developed to assess consistency across both populations and to determine if any additional factors (such as mood and sleep) predicted QoL.

Results

1,810 BSRBR-AS participants were eligible for the current study, 67% of whom were male, median age 49 years (interquartile range 38-61). 80% of those tested were HLA-B27 positive and the majority of patients (67%) met the modified New York Criteria for AS. Of the five factors included in the SIRAS model; disease activity, physical function, fatigue and widespread pain remained significantly associated with QoL in the BSRBR-AS study. Spinal mobility was no longer significantly associated. Within the de-novo model eight independent factors predicted ASQoL score: disease activity (coefficient 0.31, 95% (confidence interval 0.14, 0.47)), physical function (0.59 (0.45, 0.73)), depression (HADS: 0.16 (0.09, 0.24)), sleep disturbance (0.08 (0.04, 0.13)), activity impairment (0.04 (0.02, 0.05)), fibromyalgia (SSS: 0.24 (0.13, 0.35), WPI: 0.10 (0.03, 0.17)) and tobacco smoking (vs. non-smoker: 0.66 (0.10, 1.21)).

Conclusion

Current EULAR guidelines for management of axSpA targeting disease activity and physical function are supported by the current findings which suggest both are consistently important predictors of QoL. However, additional factors such as fatigue, sleep disturbance and mood also contribute to QoL and should be considered additional targets within future axSpA management strategies.

Disclosures

L.E. Dean None. O. Rotariu None. G.T. Jones None. E. Pathan Other; E.P. has received salary funding from Jansen (2019) and Merck (2018). G.J. Macfarlane None.

P246 Predicting non-response to biologic therapy amongst patients with axSpA: results from the British Society for Rheumatology Biologics Register

Background

Biologic therapies have transformed treatment for axial spondyloarthritis (axSpA). However, although studies report overall benefits, these are average effects. There remains a subset of patients in whom response is not achieved. Here, we aimed to identify characteristics of patients who may need additional therapeutic approaches to optimise outcome.

Methods

The British Society for Rheumatology Biologics Register for Ankylosing Spondylitis (BSRBR-AS) is a prospective cohort of axSpA patients recruited from 83 centres across Great Britain. All patients were biologic-naïve at recruitment, however those in the “biologic” cohort commenced a biologic therapy shortly thereafter, or during follow-up. Clinical data was collected from medical records, and socio-economic/patient reported outcomes via questionnaires. Response was assessed at first follow-up, between 10 weeks and 9 months from therapy commencement, and defined in four ways: ASAS20 and ASAS40 criteria, ≥1.1 reduction in ASDAS, and achieving moderate/inactive ASDAS (&lt;2.1). Factors associated with non-response were assessed by logistic regression and parsimonious models identified using stepwise methods. The ability to predict non-response was assessed by positive predictive value (PPV).

Results

335 biologic participants provided information at a median follow-up of 14 weeks (inter-quartile range (IQR) 12-17). Median age was 47 years (IQR 36-56), 69% were male and 61% met AS modified New York criteria. The proportion meeting response varied by criteria: ASAS20 52%, ASAS40 33%, ASDAS reduction 47% and ASDAS &lt;2.1 35%. Socio-economic circumstances predicted non-response, specifically (in all models) work status and (in some models) fewer years of education (Table 1). Poorer mental health and high number of co-morbidities was associated with non-response across multiple (but not all) outcomes, while body mass index, enthesitis and gender were included in models for a single outcome. Disease-specific factors were largely not associated with non-response. All models demonstrated a good level of fit and were effective at predicting non-response (PPV 65%-77%).

Conclusion

We have identified factors which predict non-response to biologic therapy, some of which may be modifiable and others which identify patients who are unlikely to benefit from biologic therapy alone. In such patients additional/alternative treatment strategies should be considered to maximise the benefits which others gain from biologic therapy.

Disclosures

L.E. Dean None. E. Pathan Other; E.P. has recieved salary funding from Jansen (2019) and Merck (2018). G.T. Jones None. G.J. Macfarlane None.

P257 Real-world evidence of TNF inhibition in axial spondyloarthritis: can we generalise the results from clinical trials?

Background

The development and utility of management guidelines assumes that clinical trial findings are generalisable. Seldom is data available to test this. We aimed to determine, in the British Society for Rheumatology Biologics Register for Ankylosing Spondylitis (BSRBR-AS), the proportion of patients commencing TNF inhibition (TNFi) that would/would not have been eligible for clinical trials that led to TNFi treatment guidelines, and whether treatment response differed between the trials and this real-world population.

Methods

Biologic-naïve spondyloarthritis patients were recruited from across Great Britain. Data was obtained from clinical records, and participants completed postal questionnaires. Participant characteristics were extracted from the placebo-controlled randomised trials in the NICE Health Technology Assessment: TNF-alpha inhibitors for ankylosing spondylitis and non-radiographic axial spondyloarthritis (TA383). Descriptive statistics were used to examine differences, including treatment response (ASAS-20), between BSRBR-AS participants who would/would not have been eligible for the clinical trials, and the trial participants.

Results

816/2420 (34%) BSRBR-AS participants were commencing TNFi. They were younger (mean age 44 versus 50yrs) with shorter disease duration (15 versus 22yrs), more active disease (BASDAI 6.4 versus 4.0), and poorer function (BASFI 6.2 versus 3.8). Fourteen clinical trials were identified. Compared to trial populations, fewer BSRBR-AS participants were male (67% versus 71%; difference: -4.1% (95%CI: -7.8%, -0.4%)) and fewer were HLA-B27 positive (76% versus 82%; difference: -6.6% (-10.6%, -2.6%)). BSRBR-AS participants were 6yrs older than trial participants, with longer symptom duration. They reported similar disease activity (BASDAI: 6.4 versus 6.2; difference 0.2 (-0.3, 0.7)), although significantly poorer function (BASFI: 6.2 versus 5.1; difference 1.1 (0.5, 1.8)) and spinal mobility (BASMI: 4.2 versus 3.3; difference 1.0 (0.8, 1.1)). Only 333 (41%) of BSRBR-AS participants commencing TNFi would have been eligible for any of the relevant trials. Ten trials reported ASAS20 response criteria, and 864/1401 participants reported a positive treatment response (61.7%). Follow-up data was available for 318 (39%) BSRBR-AS participants, of whom 163 (51.3%) achieved an ASAS20 treatment response (difference: 10.4% (4.4%, 16.5%)). There was no difference in ASAS20 response between those who would/would not have been eligible for clinical trials (50% versus 52%; difference 2.0% (-9.4%, 13.4%)).

Conclusion

In this real-world population, although the likelihood of meeting response criteria was unrelated to factors determining trial eligibility, the proportion of patients responding to TNFi was lower than in the clinical trial literature. Could this be explained by selection bias? Although fewer BSRBR-AS participants provided follow-up data than in the clinical trials, to account for the observed difference participants lost to follow-up would have to be one-third more likely to achieve ASAS20 response than those who provided follow-up data. We believe this is unlikely. These findings have important implications for the generalisability of trial results, and also for the cost-effectiveness of TNFi agents.

Disclosures

G.T. Jones: Grants/research support; GTJ is/was a grant holder for research funded by Pfizer, AbbVie, UCB and Celgene., GTJ is/was involved in research that received financial support from Novartis. L.E. Dean: Grants/research support; LED is/was involved in research that received financial support from Pfizer, AbbVie, UCB and Novartis. E. Pathan: None. G.J. Macfarlane: Grants/research support; GJM is/was a grant holder for research funded by Pfizer, AbbVie, UCB and Celgene., GJM is/was involved in research that received financial support from Novartis.

Impact of Smoking in Response to Tumor Necrosis Factor Inhibitors in Axial Spondyloarthritis: Methodologic Considerations for Longitudinal Observational Studies

OBJECTIVE

Observational data facilitate examination of treatment-effect heterogeneity, but the risk of bias is substantial. The present study was undertaken to highlight methodologic considerations through an analysis of whether smoking affects response to tumor necrosis factor inhibitors (TNFi) in axial spondyloarthritis (SpA).

METHODS

We used longitudinal data from the British Society for Rheumatology Biologics Register for Ankylosing Spondylitis. Participants fulfilling the Assessment of SpondyloArthritis international Society criteria for axial SpA who started their first TNFi were eligible for analysis. In comparing the impact of smoking status, weighted generalized estimating equations were used to examine changes in several continuous outcome measures, including the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and the Ankylosing Spondylitis Disease Activity Score (ASDAS). Inverse probability weights were used to account for differences in baseline covariates and excluded participants. We separately assessed response in the first 3 months to account for nonrandom dropout.

RESULTS

For 840 participants who started on TNFi, 1,641 assessments from 627 individuals were analyzed (69% male, mean age 46 years). A total of 33% were current smokers and 30% ex-smokers. Ex-smokers and current smokers had worse disease than never smokers at baseline. Accounting for these differences, response did not differ according to smoking status. Compared to never smokers, ex-smokers (β = -0.6, 95% confidence interval [95% CI] -1.4, 0.3) and current smokers (β = -0.4, 95% CI -1.1, 0.4) had a similar response according to the BASDAI and ASDAS (ex-smokers β = -0.1, 95% CI -0.5, 0.3; current smokers β = -0.01, 95% CI -0.4, 0.4) at 3 months.

CONCLUSION

TNFi response did not differ according to baseline smoking status in this UK cohort. Conflicting results from previous studies were likely due to methodologic differences. This analysis highlights potential sources of bias that should be addressed in future studies.

Associations between smoking and extra-axial manifestations and disease severity in axial spondyloarthritis: results from the BSR Biologics Register for Ankylosing Spondylitis (BSRBR-AS)

OBJECTIVE

The effects of smoking on disease manifestations in axial SpA are inadequately described. Utilizing a large and well-characterized cohort, we investigated the association between smoking and extra-axial manifestations, and smoking and disease severity measures.

METHODS

Baseline data from the British Society for Rheumatology Biologics Register for Ankylosing Spondylitis were explored. Our analyses focused on extra-axial manifestations and other disease severity measures, including scales for fatigue, sleep, anxiety and depression. Logistic and linear models were used to quantify associations between disease characteristics according to smoking status (current/ex/never) and quantity (heavy/light), adjusting for age, gender, BMI, education, deprivation, comorbidities, symptom duration and alcohol status.

RESULTS

A total of 2031 participants were eligible for the current analysis (68% male, mean age 49 years). Of these, 24% were current and 32% ex-smokers. When compared with non-smokers, current smokers had lower odds of uveitis [OR 0.7, 95% CI 0.5-0.9] and higher odds of psoriasis (ORadj 1.6, 95% CI 1.1-2.3). Ex- and current smokers had incrementally more severe disease than never smokers, with higher BASDAI (β = 0.3, 95% CI 0.1-0.6; β = 0.9, 95% CI 0.6-1.2) and BASFI (β = 0.5, 95% CI 0.2-0.8; β = 1.3, 95% CI 1.0-1.6); similar associations were observed for fatigue, sleep, anxiety and depression.

CONCLUSION

In this large cross-sectional study, we observed that smoking is independently associated with an adverse disease profile in axial SpA, including worse fatigue, sleep, anxiety and depression, and higher odds of psoriasis. The paradoxical association between current smoking and reduced odds of uveitis is interesting and warrants further investigation.

Determining factors related to poor quality of life in patients with axial spondyloarthritis: results from the British Society for Rheumatology Biologics Register (BSRBR-AS)

OBJECTIVE

To determine modifiable factors associated with poor quality of life (QoL) in patients with axial spondyloarthritis (axSpA).

METHODS

Analysis of data from the British Society for Rheumatology Biologics Register in Ankylosing Spondylitis (BSRBR-AS) and validation of a previous model using data from 1810 patients with axSpA recruited during 2012-2017. Data collected included clinical and patient-reported measures. QoL was assessed using the Ankylosing Spondylitis Quality of Life (ASQoL) measure. Linear regression models predicting ASQoL scores were used first to validate a previous model from a national study, to extend this with additional information available in BSRBR-AS and finally to identify a 'de novo' model from BSRBR-AS of which factors impact on poor QoL.

RESULTS

Four out of five factors included in a previous model of poor QoL in patients with axSpA were confirmed: Bath Ankylosing Spondylitis Disease Activity Index and Bath Ankylosing Spondylitis Functional Index, fatigue and widespread pain, although the performance of the model was improved by the addition of measures of mood and sleep disturbance. In a de novo model in BSRBR-AS, there were six factors (other than disease activity and function) that predicted ASQoL: depression (β=0.16), sleep disturbance (β=0.08), activity impairment (β=0.04), fibromyalgia (Symptom Severity Scale (β=0.24) and Widespread Pain Index (β=0.10)) and tobacco smoking (β=0.66).

CONCLUSION

This study confirms that poor QoL in patients with axSpA, in addition to high disease activity and poor function, is independently influenced by sleep disturbance, mood and widespread pain. These additional factors are not considered targets for treatment in current European League Against Rheumatism (EULAR) guidelines for managing the condition.

Smoking status and cause-specific discontinuation of tumour necrosis factor inhibitors in axial spondyloarthritis

Background

The impact of smoking on TNF inhibition (TNFi) therapy is unclear. We examined the effect of smoking on all-cause and cause-specific TNFi discontinuation in axial spondyloarthritis (axSpA).

Methods

We used longitudinal data from the British Society for Rheumatology Biologics Register for Ankylosing Spondylitis (BSRBR-AS). Patients fulfilling the ASAS criteria for axSpA, who started their first TNFi, were eligible for analysis. Inverse-probability weights were used to balance differences in baseline disease severity and other confounders. We used marginal structural Cox proportional hazard models to estimate hazard ratios (HR) for TNFi discontinuation according to smoking status. In analyses of cause-specific discontinuation, competing risk events were considered as censoring, using inverse-probability weights.

Results

A total of 758 participants were included in the analysis (66% male, mean age 45 years), providing 954 patient-years of follow-up. TNFi was discontinued in 174 (23%) patients, among whom 26% stopped due to infections, 20% due to other adverse events and 44% due to inefficacy or other reasons. Thirty-four percent were current smokers and 30% ex-smokers. Compared to never smokers, current smokers’ risk of TNFi discontinuation was HR 0.79 (95%CI 0.53 to 1.20) and ex-smokers HR 0.68 (95%CI 0.45 to 1.04). Our data did not show evidence that current smoking influenced discontinuation due to infections (HR 0.79, 95%CI 0.40 to 1.54), other adverse events (HR 0.86, 95%CI 0.41 to 1.78) or inefficacy/other causes (HR 1.44, 95%CI 0.86 to 2.41).

Conclusion

Baseline smoking status did not impact TNFi discontinuation in this UK cohort of axSpA participants.

Electronic supplementary material

The online version of this article (10.1186/s13075-019-1958-z) contains supplementary material, which is available to authorized users.

Health gains, costs and cost-effectiveness of a population-based screening programme for abdominal aortic aneurysms

BACKGROUND

Abdominal aortic aneurysm (AAA) rupture carries a high fatality rate. AAAs can be detected before rupture by abdominal ultrasound imaging, allowing elective repair. Population-based screening for AAA in older men reduces AAA-related mortality by about 40 per cent. The UK began an AAA screening programme offering one-off scans to men aged 65 years in 2009. Sweden has a similar programme. Currently, there is no AAA screening programme in New Zealand. This cost-utility analysis aimed to assess the cost-effectiveness of a UK-style screening programme in the New Zealand setting.

METHODS

The analysis compared a formal AAA screening programme (one-off abdominal ultrasound imaging for about 20 000 men aged 65 years in 2011) with no systematic screening. A Markov macrosimulation model was adapted to estimate the health gains (in quality-adjusted life-years, QALYs), health system costs and cost-effectiveness in New Zealand. A health system perspective and lifetime horizon was adopted.

RESULTS

With New Zealand-specific inputs, the adapted model produced an estimate of about NZ $15 300 (€7746) per QALY gained, with a 95 per cent uncertainty interval (UI) of NZ $8700 to 31 000 (€4405 to 15 694) per QALY gained. Health gains were estimated at 117 (95 per cent UI 53 to 212) QALYs. Health system costs were NZ $1·68 million (€850 535), with a 95 per cent UI of NZ $820 200 to 3·24 million (€415 243 to €1·65 million).

CONCLUSION

Using New Zealand's gross domestic product per capita (about NZ $45 000 or €22 100) as a cost-effectiveness threshold, a UK-style AAA screening programme would be cost-effective in New Zealand.