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.

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.

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.

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 (<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 <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.

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.

Influence of co-morbid fibromyalgia on disease activity measures and response to tumour necrosis factor inhibitors in axial spondyloarthritis: results from a UK national register

Objective

To quantify the extent to which co-morbid FM is associated with higher disease activity, worse quality of life (QoL) and poorer response to TNF inhibitors (TNFis) in patients with axial SpA.

Methods

A prospective study recruiting across 83 centres in the UK. Clinical information and patient-reported measures were available, including 2011 criteria for FM. Multivariable linear regression was used to model the effect of meeting the FM criteria on disease activity, QoL and response to TNFis.

Results

A total of 1757 participants were eligible for analyses, of whom 22.1% met criteria for FM. Those with co-morbid FM criteria had higher disease activity [BASDAI average difference FM⁺ − FM⁻ 1.04 (95% CI 0.75, 1.33)] and worse QoL [Ankylosing Spondylitis Quality of Life score difference 1.42 (95% CI 0.88, 1.96)] after adjusting for demographic, clinical and lifestyle factors. Among 291 participants who commenced biologic therapy, BASDAI scores in those with co-morbid FM were 2.0 higher at baseline but decreased to 1.1 higher at 12 months. There was no significant difference in the likelihood of meeting Assessment of SpondyloArthritis international Society 20 criteria at 12 months. Less improvement in disease activity and QoL over 3 months of TNFi therapy was most strongly related to high scores on the FM criteria symptom severity scale component.

Conclusion

Fulfilling criteria for FM has a modest impact on the assessment of axial SpA disease activity and QoL and does not significantly influence response to biologic therapy. Those with a high symptom severity scale on FM assessment may benefit from additional specific management for FM.

AxSpA patients who also meet criteria for fibromyalgia: identifying distinct patient clusters using data from a UK national register (BSRBR-AS)

Background

Around 1 in 8 patients with axial spondyloarthritis (axSpA) also meet criteria for fibromyalgia and such patients have considerable unmet need. Identifying effective therapy is important but to what extent fibromyalgia-like symptoms relate to axSpA disease severity has not been established. The aim of the current analysis was to determine whether distinct clusters of axSpA patients exist and if so to determine a) whether they differ in terms of prevalence of fibromyalgia and b) the features of patients in clusters with high prevalence.

Methods

The British Society for Rheumatology Biologics Register (BSRBR-AS) recruited axSpA patients from 83 centres 2012-2017. Clinical data, and information from patients was collected (including research criteria for fibromyalgia). Cluster analysis was undertaken using split samples for development and validation both in the whole population and the sub-group which met fibromyalgia criteria.

Results

One thousand three hundred thirty-eight participants were included of whom 23% met research criteria for fibromyalgia. Four clusters were identified. Two exhibited very high disease activity, one which was primarily axial (n = 347) and a smaller cluster (n = 32) with axial and peripheral disease, and in both groups more than half of members met criteria for fibromyalgia. The remaining two clusters (n = 437, n = 462) had overall less severe disease however the one which showed greater disease activity and poorer quality of life had a higher proportion meeting fibromyalgia criteria (16% v. 4%). Within those meeting fibromyalgia criteria there were three clusters. The two main groups were defined by level of symptom severity with a smaller third cluster noted to have high average swollen and tender joint counts and high levels of comorbidity.

Conclusions

The major feature defining clusters with a high proportion of persons meeting criteria for fibromyalgia is high axSpA disease activity although clusters with features of fibromyalgia in the absence of high disease activity also show moderately high prevalence. Management may be most successful with pharmacologic therapy to target inflammation but enhanced by the concurrent use of non-pharmacologic therapy in such patients.

The link between ankylosing spondylitis and oral health conditions: two nested case-control studies using data of the UK Biobank

Ankylosing Spondylitis (AS) is an inflammatory rheumatic disease that affects the axial skeleton and the sacroiliac joints. Recent studies investigated the link between AS and oral diseases, particularly periodontitis. Others suggested that periodontitis may have a role in the pathogenesis of rheumatic diseases. Objective: The aim of this study is to investigate the association between AS and oral conditions. Material and Methods: This research was conducted using the UK Biobank Resource under Application Number 26307. The UK Biobank recruited around 500000 participants throughout Great Britain. Clinical records were available for 2734 participants. Two case-control studies were conducted based on whether AS was self-reported or clinically diagnosed. Oral conditions were identified using self-reported reports of oral ulcers, painful gums, bleeding gums, loose teeth, toothache, and dentures. The association between AS and oral conditions was assessed using logistic regression adjusted for age, gender, educational level, smoking status, alcohol consumption, and body mass index. Results: A total of 1307 cases and 491503 control participants were eligible for the self-reported AS study. The mean age was 58 years for the cases [7.5 standard deviation (SD)] and 57 years for the control groups (8.1 SD). Also, 37.1% of the cases and 54.2% of the control participants were females. Among the oral conditions, only oral ulcers were strongly associated with AS [1.57 adjusted odds ratio (OR); 95% confidence interval (CI) 1.31 to 1.88]. For the study of clinically diagnosed AS, 153 cases and 490351 control participants were identified. The mean age for both cases and control groups was 57 years; 7.6 SD for the cases and 8.1 for the control group. Females corresponded to 26.1% of the cases, and 54.2% of the control participants. Clinically diagnosed AS was associated with self-reported oral ulcers (2.17 adjusted OR; 95% CI 1.33 to 3.53). Conclusion: Self-reported and clinically diagnosed AS populations have increased risk of reporting oral ulcers. Further investigations are required to assess the link between a specific type of oral condition and AS.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Relationship between diet and ankylosing spondylitis: A systematic review

The question of whether diet plays a role in the onset of ankylosing spondylitis (AS) or can affect the course of the disease is an important one for many patients and healthcare providers. The aims of this study were to investigate whether: 1) patients with AS report different diets to those without AS; 2) amongst patients with AS, diet is related to severity; 3) persons with particular diets are less likely to develop AS; 4) specific dietary interventions improve the AS symptoms. The review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Medline, Embase, Cochrane Library, and reference lists of relevant articles were searched. Two authors independently selected eligible studies, assessed the quality of included trials, and extracted the data. Sixteen studies (nine observational and seven interventions) were included in the review. Due to the heterogeneity of the study designs and analyses, the results could not be aggregated. Evidence on a possible relationship between AS and diet is extremely limited and inconclusive due to the majority of included studies being small, single studies with moderate-to-high risk of bias, and insufficient reporting of results.

Oral Health and Risk of Arthritis in the Scottish Population: Results from the Scottish Health Survey

Objectives

To investigate the link between self-reported oral health and arthritis in the Scottish population using data from the Scottish Health Survey.

Material and Methods

Data were available from 2008 to 2013 on self-reported arthritis, oral health conditions and oral hygiene habits from the Scottish Health Survey. Arthritis was defined in this survey by self-reported long standing illness, those who reported having arthritis, rheumatism and/or fibrositis. Oral conditions were defined by self-reported bleeding gums, toothache, biting difficulties and/or edentulousness. Oral hygiene habits were defined by self-reported brushing teeth and/or using dental floss on daily basis. Logistic regression was used for statistical analysis adjusted for age, gender, qualification, smoking and body mass index.

Results

Prevalence of self-reported arthritis was 9.3% (95% confidence interval [CI] = 9.03 to 9.57). Those who reported having bleeding gums (adjusted odds ratio [OR] = 1.63; 95% CI = 1.35 to 1.96), toothache (OR = 1.32; 95% CI = 1.16 to 1.5), biting difficulties (OR = 1.95; 95% CI = 1.62 to 2.34), and being edentulous (OR = 1.22; 95% CI = 1.08 to 1.37) had an increased risk of arthritis. Brushing teeth (OR = 1.25; 95% CI = 0.74 to 2.12), and using dental floss (OR = 1.11; 95% CI = 0.89 to 1.39) were not associated with arthritis.

Conclusions

Self-reported oral conditions were associated with increased risk of self-reported arthritis. Oral hygiene habits were not associated with self-reported arthritis. Further investigation is required to assess the causal association between oral hygiene, oral disease and arthritis.

The British Society for Rheumatology Biologics Registers in Ankylosing Spondylitis (BSRBR-AS) study: Protocol for a prospective cohort study of the long-term safety and quality of life outcomes of biologic treatment

BACKGROUND

Axial spondyloarthropathy typically has its onset in early adulthood and can impact significantly on quality of life. In the UK, biologic anti-tumour necrosis factor therapy is recommended for patients who are unresponsive to non-steroidal anti-inflammatory drugs. There remain several unresolved issues about the long-term safety and quality of life outcomes of biologic treatment in axial spondyloarthropathy. Long-term "real-world" surveillance data are required to complement data from randomised controlled trials.

METHODS/DESIGN

We are conducting a UK-wide prospective cohort study of patients with axial spondyloarthropathy who are naïve to biologic therapy at the time of recruitment. Those about to commence anti-tumour necrosis factor biologic therapy will enter a "biologic" sub-cohort with other patients assigned to a "non-biologic" sub-cohort. The primary objective is to determine whether the use of biologic therapy is associated with an increased risk of serious infection, while secondary objectives are to assess differences in malignancy, serious comorbidity, all-cause mortality but also assess impact on specific clinical domains (physical health, mental health and quality of life) including work outcomes between biologic and non-biologic patient cohorts. Patients will be followed-up for up to 5 years. Data are obtained at baseline and at standard clinical follow-up visits - at 3, 6 and 12 months and then annually for the biologic cohort and annually for the non-biologic cohort. This study will also collect biological samples for genetic analysis.

DISCUSSION

Although biologic therapy is widely used for ankylosing spondylitis patients who are unresponsive to non-steroidal anti-inflammatory drugs, the majority of the available safety information comes from rheumatoid arthritis, where increased infection risk has consistently been shown. However, given the typical demographic differences between rheumatoid arthritis and axial spondyloarthropathy patients, it is important to develop an epidemiologically rigorous cohort of patients receiving biologic therapy to effectively evaluate outcomes with regard not only to safety but also to quantify benefits across clinical, psychosocial and work outcomes.

CLINICAL TRIAL REGISTRATION

This is an observational cohort study and clinical trial registration was not required or obtained.

Anti-tumour necrosis factor treatment increases circulating T helper type 17 cells similarly in different types of inflammatory arthritis

We investigated changes in circulating T helper type 17 (Th17) cells following anti-tumour necrosis factor (TNF) in rheumatoid arthritis (RA), ankylosing spondylitis (AS) and psoriatic arthritis (PsA) patients. Peripheral blood mononuclear cells (PBMC) were isolated from 25 RA, 15 AS and eight PsA patients at baseline 4 and 12 weeks after treatment, and Th17 cell frequencies were analysed using interleukin (IL)-17 enzyme-linked immunospot (ELISPOT) and flow cytometry. A significant increase in IL-17-producing cells was observed by ELISPOT in RA and AS patients at 12 weeks. Flow cytometry confirmed significant increases in CD4(+) IL-17(+) cells at 12 weeks in RA and AS and 4 weeks in PsA patients. Anti-TNF treatment increases circulating Th17 cells in three different diseases.

Incomplete response of inflammatory arthritis to TNFα blockade is associated with the Th17 pathway

OBJECTIVES

To establish if changes in Th1/Th17 cell populations previously reported in experimental arthritis occur in patients with rheumatoid arthritis (RA) treated with anti-tumour necrosis factor α (TNFα) agents, and whether the therapeutic response to anti-TNFα is compromised in patients and mice because of elevated Th17/IL-17 levels. Finally, to assess the efficacy of combined blockade of anti-TNFα and anti-IL-17 in experimental arthritis.

METHODS

A longitudinal study of two independent cohorts (cohort 1, n=24; cohort 2, n=19) of patients with RA treated with anti-TNFα biological agents was carried out to assess their Th17/IL-17 levels before and after the start of anti-TNFα therapy. IL-12/23p40 production was assessed in plasma Peripheral blood lymphocytes (PBLs) and monocytes. Mice with collagen-induced arthritis (CIA) were treated with anti-TNFα alone, anti-IL17 alone or a combination of the two. Efficacy of treatment and response was assessed from changes in Disease Activity Score 28-erythrocyte sedimentation rate scores in patients, and in clinical scores and histological analysis in CIA.

RESULTS

Significant increases in circulating Th17 cells were observed in patients after anti-TNFα therapy and this was accompanied by increased production of IL-12/23p40. There was an inverse relationship between baseline Th17 levels and the subsequent response of patients with RA to anti-TNFα therapy. In addition, PBLs from non-responder patients showed evidence of increased IL-17 production. Similarly, in anti-TNFα-treated mice, there was a strong correlation between IL-17 production and clinical score. Finally combined blockade of TNFα and IL-17 in CIA was more effective than monotherapy, particularly with respect to the duration of the therapeutic effect.

CONCLUSIONS

These findings, which need to be confirmed in a larger cohort, suggest that a Th17-targeted therapeutic approach may be useful for anti-TNFα non-responder patients or as an adjunct to anti-TNFα therapy, provided that safety concerns can be addressed.

Pyrexia of unknown origin: Kikuchi-Fujimoto disease

A case of Kikuchi-Fujimoto disease is presented in the context of pyrexia of unknown origin. Although no specific etiology has been identified, several reported cases are associated with a variety of viruses, toxoplasma, or systemic lupus erythematosus. We present a case and discuss the implications for management.

Rheumatoid arthritis and the kidney

It is clear that kidney is involved in rheumatoid arthritis (RA) with both glomerular and tubular damage. Renal disease in RA however is usually asymptomatic and is detected only on laboratory investigations. It is often difficult to differentiate between damage due to disease activity and that due to drugs used to treat RA. Although there are a number of parameters to study renal function, these cannot be applied to day to day practice and still remain research tools. In such a scenario, it is important to periodically monitor serum creatinine and carry out urine examination so as to pick up the earliest signs of renal dysfunction.

Myelodysplasia and acute myeloid leukaemia in a case of rheumatoid arthritis with secondary amyloidosis treated with chlorambucil

Immunosuppressive therapy related secondary haematologic malignancy is well reported. A 52 years lady with established rheumatoid arthritis developed reactive amyloidosis. This was initially treated with colchicine and cyclophosphamide and later with chlorambucil. Ten months after stopping chlorambucil she developed pancytopenia and vitamin B12 deficient megaloblastic anaemia. The pancytopenia was refractory to vitamin B12 supplements and a repeat bone marrow confirmed myelodysplasia (FABI RAEB-T). Within three weeks of this diagnosis she evolved into acute myeloid leukaemia and expired due to refractory thrombocytopenia and uncontrolled bleeding. This case stresses the need for long term follow up of RA patients treated with alkylating agents.

A longitudinal study of serum creatinine levels in patients of rheumatoid arthritis on long term NSAID therapy

AIM

Primary: To study the effect of long term NSAID therapy on serum creatinine in patients of rheumatoid arthritis. Secondary: To study the effect of discontinuation, reduction in the dose or continuation of NSAID and of rechallenge.

MATERIAL AND METHODS

Case records of RA patients with a minimum two years of follow up were analysed. Age, sex, duration of RA, type, dose and duration of NSAID and DMARD therapy, co-morbid conditions and serial serum creatinine levels were charted.

RESULTS

Ninety nine case records were studied. Incidence of abnormal creatinine level (renal insufficiency) defined as rise in creatinine equal to or above the upper limit of normal was 27.7%. This rise was asymptomatic in all patients. No NSAID was particularly associated with an increased risk in renal insufficiency. The rise of serum creatinine was reversible in most patients irrespective of discontinuation or continuation of NSAID but settled at a higher level. Rechallenge resulted in rise of serum creatinine in 50% patients. Hypertension, DM, IHD and diuretics carried a higher but not statistically significant risk of renal insufficiency.

CONCLUSION

NSAID-induced asymptomatic rise of creatinine in patients of RA on long term NSAIDs is common. It is mostly reversible. Regular monitoring of serum creatinine is essential.

Ultrasonography in the diagnosis and follow-up of idiopathic inflammatory myopathies--a preliminary study

OBJECTIVE

To study the utility of ultrasonography (US) in diagnosis and follow up of patients with idiopathic inflammatory myopathy (IIM).

METHODS

High-resolution US of thigh muscles was recorded at baseline and after six months of treatment in eleven patients of early, active, untreated IIM. Parameters studied were muscle power, timed function tests (TFT), muscle enzymes, electromyography, muscle histopathology and US parameters such as echogenicity of muscle and perimysial septa count per 1 cm muscle width.

RESULTS

There was a significant increase in muscle echogenicity and septa count of patients as compared to those of controls (p = 0.002 and 0.00003, respectively). These abnormalities resolved on treatment. Muscle echogenicity and perimysial septa count showed mild positive correlation with walking time, 4-step climbing and myopathic pattern on EMG. Perimysial septa count in addition correlated weakly with creatine phosphokinase, lactate dehydrogenase and muscle fibre necrosis.

CONCLUSION

US seems to be a useful, non-invasive, cheap modality to monitor the disease course in IIM. Larger studies to confirm these primary findings are warranted.

Treatment of AA amyloidosis in rheumatoid arthritis

Four patients of rheumatoid arthritis (RA) with biopsy confirmed AA amyloidosis were treated with chlorambucil. All had established but uncontrolled RA with a persistently raised ESR. Moderate (> 1 gm, < 3.5 gm/d) to nephrotic range (> 3.5 gm/d) proteinuria and a relatively well preserved renal function was noted in three patients. One patient had deranged renal function and required dialysis. On chlorambucil, there was complete recovery, partial improvement and no improvement in one patient each. The fourth patient required haemodialysis, did not tolerate chlorambucil and succumbed to the illness. Therapy with chlorambucil can benefit some patients of RA with AA amyloidosis. Leucopenia is the most important dose limiting side effect.

Efficacy of isoniazid prophylaxis in patients with systemic lupus erythematosus receiving long term steroid treatment

OBJECTIVE

To study the efficacy of isoniazid prophylaxis (INHP) in patients with systemic lupus erythematosus (SLE) receiving long term glucocorticosteroid treatment.

PATIENTS AND METHODS

Treatment with INHP (5 mg/kg/day, max 300 mg/day) together with pyridoxine 10 mg/day for one year was started in all patients with SLE seen between January 1994 and December 1999 and followed up thereafter. Clinical examination and chest radiography were carried out in all patients before the start of INHP treatment. A liver profile was obtained only if liver toxicity was suspected owing to nausea, loss of appetite, and icterus. Only the data of those patients who completed the INHP treatment or who were withdrawn owing to toxicity have been analysed. This was compared with the results of an earlier study of the incidence of tuberculosis (TB) in patients with SLE not receiving INHP.

RESULTS

Ninety seven patients were included, of whom 95 completed one year's treatment with INHP. Treatment was discontinued in two owing to toxicity: hepatitis in one and peripheral neuropathy in one, at eight and 10 months, respectively. One patient developed TB within one month of starting INHP. Seventy patients were followed up further for at least one year (mean 26.4 months, range 12-60 months) after completion of the INHP treatment. During this period one patient developed TB after one month. No deaths due to TB or hepatitis occurred. In comparison with earlier series the incidence of TB decreased from 11% to 2%, a reduction of 82%. The cost of treatment for each case of TB prevented in the first year was 5800 rupees.

CONCLUSION

INHP is safe and effective in SLE.