Early axial spondyloarthritis according to the ASAS consensus definition: characterisation of patients and effectiveness of a first TNF inhibitor in a large observational registry.

OBJECTIVE: To characterise the population fulfilling the Assessment of SpondyloArthritis international Society (ASAS) consensus definition of early axial spondyloarthritis (axSpA) and to determine the effectiveness of a first tumour necrosis factor inhibitor (TNFi) in early versus established axSpA in a large observational registry. METHODS: A total of 3064 patients with axSpA in the Swiss Clinical Quality Management registry with data on duration of axial symptoms were included (≤2 years=early axSpA, N=658; >2 years=established axSpA, N=2406). Drug retention was analysed in patients starting a first TNFi in early axSpA (N=250) versus established axSpA (N=874) with multiple-adjusted Cox proportional hazards models. Adjusted logistic regression analyses were used to determine the achievement of the ASAS criteria for 40% improvement (ASAS40) at 1 year. RESULTS: Sex distribution, disease activity, impairments of function and health-related quality of life were comparable between patients with early and established axSpA. Patients with established disease were older, had more prevalent axial radiographical damage and had a higher impairment of mobility. A comparable TNFi retention was found in early versus established disease after adjustment for age, sex, human leucocyte antigen-B27 status, education, body mass index, smoking, elevated C reactive protein and sacroiliac inflammation on MRI (HR 1.05, 95% CI 0.78 to 1.42). The adjusted ASAS40 response was similar in the two groups (OR 1.09, 95% CI 0.67 to 1.78). Results were confirmed in the population fulfilling the ASAS classification criteria. CONCLUSION: Considering the recent ASAS definition of early axSpA, TNFi effectiveness seems comparable in early versus established disease.

Impact of sex on spinal radiographic progression in axial spondyloarthritis: a longitudinal Swiss cohort analysis over a period of 10 years.

OBJECTIVE: To investigate sex differences in spinal radiographic progression in axial spondyloarthritis (axSpA). METHODS: AxSpA patients in the Swiss Clinical Quality Management cohort with available spinal radiographs every 2 years were included. Paired radiographs were scored by two readers according to the modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS). Progression was defined as an increase of ≥2 mSASSS units in 2 years. The relationship between sex and progression was investigated with binomial generalised estimating equation models, considering baseline spinal damage as an intermediate covariate. Additional analyses included adjustments for explanatory variables and multiple imputations for missingness. RESULTS: In a total of 505 axSpA patients (317 men and 188 women), mean±SD radiographic progression over 2 years was 1.0±2.8 years in men and 0.3±1.1 years in women (p<0.001). Male sex was associated with enhanced progression in a small model not including baseline damage (OR 3.41, 95% CI 1.87 to 6.21). Both a direct effect of male sex on spinal progression, and an indirect effect, via enhancement of baseline spinal damage were significant (OR 2.06, 95% CI 1.15 to 3.67 and OR 1.04, 95% CI 1.01 to 1.07, respectively). A significant impact of male sex on spinal radiographic progression was still demonstrated after multiple adjustments for covariates known to potentially affect spinal radiographic progression (OR 1.97, 95% CI 1.04 to 3.71). CONCLUSIONS: Spinal radiographic progression in axSpA is more severe in men than in women, with three times higher odds of progression in male patients and an effect that is mediated in part through an increase in baseline radiographic damage.

Characterisation of patients with axial psoriatic arthritis and patients with axial spondyloarthritis and concomitant psoriasis in the SCQM registry.

BACKGROUND: Within the spectrum of spondyloarthritides, axial spondyloarthritis (axSpA) and psoriatic arthritis (PsA) present with overlapping features. Axial involvement in PsA (axial PsA) is treated according to recommendations for axSpA, as specific studies in axial PsA are scarce. We compared characteristics of patients with axSpA (particularly of patients with axSpA and concomitant psoriasis (pso)) with those of patients with axial PsA. METHODS: Patients with axSpA and PsA in the Swiss Clinical Quality Management (SCQM) registry were included if information on pso and axial involvement was available. Patients with AxSpA were stratified by axSpA with and without pso (axSpA±pso) and patients with PsA were stratified to axial PsA or strictly peripheral PsA. RESULTS: Previous or current psoriasis was observed in 479/4489 patients with axSpA (10.7%). Of 2631 patients with PsA, 1153 (43.8%) presented with axial involvement (opinion of the treating rheumatologist). Compared with patients with axSpA+pso, patients with axial PsA were older at symptom onset and at inclusion in SCQM, were less frequently HLA-B27 positive, had back pain less frequently and a higher prevalence of dactylitis and peripheral arthritis. A positive family history of pso or PsA was more frequent in axial PsA, while a positive family history of axSpA was more frequent in patients with axSpA+pso. Disease activity, function and mobility were comparable in axSpA+pso versus axial PsA. CONCLUSION: Patients with axial PsA differ from patients with axSpA+pso in important demographic and clinical characteristics, and genetically, but present with a comparable disease burden. Treatment studies specifically dedicated to axial PsA seem warranted.

Anaemia is associated with higher disease activity in axial spondyloarthritis but is not an independent predictor of spinal radiographic progression: data from the Swiss Clinical Quality Management Registry.

OBJECTIVE: As anaemia represents a biomarker for increased radiographic damage in rheumatoid arthritis, we aimed to investigate whether it independently predicts spinal radiographic progression in axial spondyloarthritis (axSpA). METHODS: AxSpA patients with available haemoglobin levels from the prospective Swiss Clinical Quality Management Registry were included for comparison of patients with and without anaemia. Spinal radiographic progression was assessed according to the modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS) in patients with ankylosing spondylitis (AS) if ≥ 2 sets of spinal radiographs were available every 2 years. The relationship between anaemia and progression (defined as an increase ≥ 2 mSASSS units in 2 years) was analysed with generalized estimating equation models after adjustment for the Ankylosing Spondylitis Disease Activity Score (ASDAS) and potential confounding, as well as after multiple imputations of missing values. RESULTS: A total of 212/2522 axSpA patients presented with anaemia (9%). Anaemic patients had higher clinical disease activity, higher acute phase reactants and more severe impairments in physical function, mobility and quality of life. In the subgroup of patients with AS (N = 433), a comparable mSASSS progression was found in anaemic and non-anaemic patients (OR 0.69, 95% CI 0.25 to 1.96, p = 0.49). Age, male sex, baseline radiographic damage and ASDAS were associated with enhanced progression. The results were confirmed in complete case analyses and with progression defined as the formation of ≥ 1 syndesmophyte in 2 years. CONCLUSION: Although anaemia was associated with higher disease activity in axSpA, it did not additionally contribute to the prediction of spinal radiographic progression. Key Points • Anaemia is associated with higher disease activity and more severely impaired physical function, mobility and quality of life in axSpA. • Anaemia does not provide an additional value to ASDAS for prediction of spinal radiographic progression.

Site-specific assessment of spinal radiographic progression improves detection of TNF blocker-associated disease modification in axial spondyloarthritis: longitudinal observational data from the Swiss Clinical Quality Management Registry.

OBJECTIVES: To analyse whether time-varying treatment with tumour necrosis factor inhibitors (TNFi) in radiographic axial spondyloarthritis (r-axSpA) has a differential impact on structural damage progression on different spinal segments (cervical versus lumbar spine). METHODS: Patients with r-axSpA in the Swiss Clinical Quality Management cohort were included if cervical and lumbar radiographs were available at intervals of 2 years for a maximum of 10 years. Paired radiographs were scored by two calibrated readers according to the modified Stoke Ankylosing Spondylitis Spine Score (mSASSS). The relationship between TNFi use and progression in the cervical and the lumbar spine was analysed using generalised estimating equation models and adjustment for potential confounding. Radiographic progression per spinal segment was defined as an increase of ≥ 1 mSASSS unit or by the formation of ≥ 1 new syndesmophyte over 2 years. RESULTS: Mean ± SD symptom duration was 13.8 ± 9.8 years. Mean ± SD mSASSS progression per radiographic interval was 0.41 ± 1.69 units in the cervical spine and 0.45 ± 1.45 units in the lumbar spine (p = 0.66). Prior use of TNFi significantly reduced the odds of progression in the cervical spine by 68% (OR 0.32, 95% CI 0.14-0.72), but not in the lumbar spine (OR 0.99, 95% CI 0.52-1.88). A more restricted inhibition of progression in the lumbar spine was confirmed after multiple imputation of missing covariate data (OR 0.43, 95% CI 0.24-0.77 and 0.85, 95% CI 0.51-1.41, for the cervical and lumbar spine, respectively). It was also confirmed with progression defined as formation of ≥ 1 syndesmophyte (OR 0.31, 95% CI 0.12-0.80 versus OR 0.56, 95% CI 0.26-1.24 for the cervical and lumbar spine, respectively). CONCLUSION: Disease modification by treatment with TNFi seems to more profoundly affect the cervical spine in this r-axSpA population with longstanding disease. Site-specific analysis of spinal progression might, therefore, improve detection of disease modification in clinical trials in axSpA.

HLA-B27 as a predictor of effectiveness of treatment with TNF inhibitors in axial spondyloarthritis: data from the Swiss Clinical Quality Management Registry.

OBJECTIVE: To explore the impact of the human leucocyte antigen (HLA)-B27 on the effectiveness of tumor necrosis factor inhibitors (TNFi) in patients with axial spondyloarthritis (axSpA). METHODS: A total of 1109 patients with available HLA-B27 status (831 B27+ patients and 278 B27- patients) fulfilling the Assessment of Spondyloarthritis international Society classification criteria for axSpA from the prospective Swiss Clinical Quality Management Registry initiating a first TNFi were included. Drug retention was investigated with multiple adjusted Cox proportional hazard models with imputation of missing values. Multiple-adjusted logistic regression analyses were used to assess the proportion of patients reaching 50% reduction in the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI50) at 1 year. RESULTS: B27+ and B27- patients differed with regard to age, sex, BASDAI, C-reactive protein (CRP), body mass index, enthesitis, uveitis, and classification status. After adjustment for potential confounders for the relationship between HLA-B27 and drug effectiveness (sex and family history of spondyloarthritis), a higher risk of drug discontinuation was found in B27- patients (HR 1.53, 95% CI 1.27-1.83). This difference decreased after additional adjustment for parameters which may act as mediators (HR 1.30, 95% CI 1.30-1.55). Male sex and elevated C-reactive protein (CRP) levels were consistently associated with longer retention. Comparable results were obtained for BASDAI50 responses. CONCLUSION: The HLA-B27 genotype is an important predictor of treatment effectiveness. Male sex and CRP seem, however, to better describe variability of response in individual patients. This data may help avoiding potential discrimination of B27- individuals with regard to TNFi initiation. Key Points • HLA-B27 is a predictor of effectiveness of TNF inhibitors in axial spondyloarthritis. • Variability of response in individual patients is better defined by sex and objective markers of disease activity, such as C-reactive protein.

Sacroiliac joint radiographic progression in axial spondyloarthritis is retarded by the therapeutic use of TNF inhibitors: 12-year data from the SCQM registry.

OBJECTIVES: To analyse the effect of tumour necrosis factor inhibitors (TNFi) on sacroiliac joint (SIJ) radiographic progression in axial spondyloarthritis (axSpA). METHODS: Patients with axSpA in the Swiss Clinical Quality Management cohort with up to 12 years of follow-up and radiographic assessments every 2 years were included. SIJs were scored by two readers according to the modified New York criteria blinded to chronology. The relationship between TNFi use before or during a 2-year radiographic interval and SIJ progression was investigated using generalised estimating equation models with adjustment for potential confounding. Progression was defined as worsening of ≥1 grade in ≥1 SIJ and ignoring a change from 0 to 1 over 2 years, if both readers agreed. A third reading of radiographs was integrated in sensitivity analyses. RESULTS: A total of 515 patients with axSpA contributed to data for 894 radiographic intervals (24 progression events). In patients with complete covariate data, prior use of TNFi reduced the odds of progression (OR 0.21, 95% CI 0.07 to 0.65). A comparable effect was found for use of TNFi for ≥1 year within a 2-year radiographic interval (OR 0.21, 95% CI 0.08 to 0.55). The inhibitory impact of TNFi was confirmed if progression was demonstrated in 2/3 readings: OR 0.50, 95% CI 0.28 to 0.89 and OR 0.46, 95% CI 0.27 to 0.78 for TNFi treatment before and for ≥1 year within the interval, respectively. CONCLUSION: TNFi are associated with deceleration of SIJ radiographic progression in patients with axSpA if treatment is continued for ≥1 year.

Current differentiation between radiographic and non-radiographic axial spondyloarthritis is of limited benefit for prediction of important clinical outcomes: data from a large, prospective, observational cohort.

OBJECTIVE: To compare disease characteristics and outcomes between patients with axial spondyloarthritis with non-radiographic disease (nr-axSpA), bilateral grade 2 sacroiliitis (r22axSpA) and unilateral/bilateral grade 3-4 sacroiliitis (r3+axSpA) according to the modified New York criteria. METHODS: We included patients with axial spondyloarthritis with available pelvic radiographs from the Swiss Clinical Quality Management Cohort. Retention of a first tumour necrosis factor inhibitor (TNFi) was investigated with multiple adjusted Cox proportional hazards models. The proportion of patients reaching 50% reduction in the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI50) at 1 year was assessed with multiple adjusted logistic regression analyses. Spinal radiographic progression, defined as an increase in ≥2 mSASSS units in 2 years, was assessed in generalised estimating equation models. RESULTS: From 2080 patients, those with nr-axSpA (n=485) and r22axSpA (n=443) presented with lower C reactive protein levels and less severe clinical spinal involvement compared with patients with r3+axSpA (n=1152). While TNFi retention was similar in r22axSpA and nr-axSpA, the risk of discontinuation was significantly lower in r3+axSpA (HR 0.60, 95% CI 0.44 to 0.82 vs nr-axSpA). BASDAI50 responses at 1 year were comparable in r22axSpA and nr-axSpA, with a better response associated with r3+axSpA (OR 2.05, 95% CI 1.09 to 3.91 vs nr-axSpA). Spinal radiographic progression was similar in r22axSpA and nr-axSpA and significantly higher in r3 +axSpA. CONCLUSION: Patients with r22axSpA are comparable to nr-axSpA patients but differ from patients with more severe sacroiliac damage with regard to treatment effectiveness and spinal radiographic progression. Therefore, current differentiation between nr-axSpA and radiographic disease seems of limited use for outcome prediction.

Differences between men and women with nonradiographic axial spondyloarthritis: clinical characteristics and treatment effectiveness in a real-life prospective cohort.

BACKGROUND: Sex differences with regard to clinical manifestations and response to tumor necrosis factor inhibitors (TNFi) have been delineated for the radiographic form of axial spondyloarthritis (axSpA). More limited evidence for a differential effectiveness of treatment in genders exists for the nonradiographic disease state (nr-axSpA). The aim of the study was to compare demographics, clinical parameters, and response to TNFi in women versus men with nr-axSpA. METHODS: We compared disease characteristics of 264 women and 231 men with nr-axSpA at inclusion in the prospective Swiss Clinical Quality Management Cohort. Response to a first TNFi was assessed in 85 women and 78 men without diagnosed co-morbid fibromyalgia. The primary outcome was the proportion of patients achieving the 40% improvement in the Assessment of SpondyloArthritis international Society criteria (ASAS40) at 1 year. Additional response outcomes were evaluated as secondary outcomes. Patients having discontinued TNFi were considered non-responders. Logistic regression analyses were adjusted for baseline differences, which might potentially mediate the effect of sex on treatment response. RESULTS: Compared to men, women had a longer diagnostic delay, a higher level of perceived disease activity, and more enthesitis and were in a lower percentage HLA-B27 positive. An ASAS40 response was achieved by 17% of women and 38% of men (OR 0.34; 95% CI 0.12, 0.93; p = 0.02). A significantly lower response rate in women was confirmed in the adjusted analysis (OR 0.19; 95% CI 0.05, 0.62; p = 0.009) as well as for the other outcomes assessed. CONCLUSION: Despite only few sex differences in patient characteristics in nr-axSpA, response rates to TNFi are significantly lower in women than in men.

Effectiveness of secukinumab versus an alternative TNF inhibitor in patients with axial spondyloarthritis previously exposed to TNF inhibitors in the Swiss Clinical Quality Management cohort.

OBJECTIVE: To compare effectiveness of treatment with secukinumab (SEC) with that of alternative tumour necrosis factor inhibitors (TNFis) in patients with axial spondyloarthritis (axSpA) after withdrawal from one or more TNFis. METHODS: Patients diagnosed as having axSpA in the Swiss Clinical Quality Management cohort were included if they had initiated SEC (n=106) or an alternative TNFi (n=284) after experiencing TNFi failure. Drug retention was investigated with matching weights propensity score (PS) analyses and multiple adjusted Cox proportional hazards models. Matching weights PS-based analyses and multiple-adjusted logistic regression analyses were used to assess the proportion of patients reaching 50% reduction in the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI50) at 1 year. RESULTS: SEC was more often used as third-line or later-line biological drug (76% vs 40% for TNFi). Patients starting SEC had higher BASDAI, Bath Ankylosing Spondylitis Functional Index, Bath Ankylosing Spondylitis Metrology Index and C reactive protein levels. A comparable risk of drug discontinuation was found for SEC versus TNFi (HR 1.14, 95% CI 0.78 to 1.68 in the PS-based analysis and HR 1.16, 95% CI 0.79 to 1.71 in the multiple-adjusted analysis). No significant difference in BASDAI50 responses at 1 year was demonstrated between the two modes of biological drug action, with CI of estimates being, however, wide (OR for SEC vs TNFi 0.76, 95% CI 0.26 to 2.18 and 0.78, 95% CI 0.24 to 2.48 in the PS-based and the covariate-adjusted model, respectively). CONCLUSION: Our data suggest a comparable effectiveness of SEC versus an alternative TNFi after prior TNFi exposure.

Spinal radiographic progression in axial spondyloarthritis and the impact of classification as nonradiographic versus radiographic disease: Data from the Swiss Clinical Quality Management cohort.

OBJECTIVE: To investigate whether spinal radiographic progression relates to structural damage at the sacroiliac level in axial spondyloarthritis (axSpA). METHODS: Patients classified as nonradiographic (nr-) and radiographic (r-) axSpA in the Swiss Clinical Quality Management cohort with radiographs performed every 2 years, scored according to the modified Stoke Ankylosing Spondylitis Spine Score (mSASSS), were included. The relationship between classification status and spinal progression during 2 years was investigated using binomial generalized estimating equations models with adjustment for sex, ankylosing spondylitis disease activity score (ASDAS) and tumour necrosis factor inhibitor treatment. Baseline spinal damage was considered an intermediate variable and included in sensitivity analyses. RESULTS: In total, 88 nr-axSpA and 418 r-axSpA patients contributed to data for 725 radiographic intervals. R-axSpA patients were more frequently male, had a longer disease duration and higher structural damage at baseline. Mean (SD) mSASSS change over 2 years was 0.16 (0.62) units in nr-axSpA and 0.92 (2.78) units in r-axSpA, p = 0.01. Nr-axSpA was associated with a significantly lower progression in 2 years (defined as an increase in ≥2 mSASSS units) in adjusted analyses (OR 0.33, 95%CI 0.13; 0.83), confirmed with progression defined as the formation of ≥1 syndesmophyte. Mediation analyses revealed that sacroiliitis exerted its effect on spinal progression indirectly by being associated with the appearance of a first syndesmophyte (OR 0.09, 95%CI 0.02; 0.36 for nr-axSpA vs r-axSpA). Baseline syndesmophytes were predictors of further progression. CONCLUSION: Spinal structural damage is mainly restricted to patients with r-axSpA, leading to relevant prognostic and therapeutic implications.

Comparison of drug survival on adalimumab, etanercept, golimumab and infliximab in patients with axial spondyloarthritis.

OBJECTIVES: To compare drug survival in patients with axial spondyloarthritis treated with different TNF inhibitors in standard dosage. METHODS: Patients fulfilling the Assessment in SpondyloArthritis international Society classification criteria for axial spondyloarthritis in the Swiss Clinical Quality Management cohort were included in this study if a first TNF inhibitor on standard dosage was started after recruitment and if a baseline visit was available. Drug maintenance up to drug discontinuation or dose escalation was compared between TNF inhibitors with multiple adjusted Cox proportional hazards models and multiple imputation for missing baseline covariate data. RESULTS: A total of 966 patients were included (adalimumab 344, etanercept 237, golimumab 214, infliximab 171). Patients on certolizumab (n = 18) were excluded. Patients starting golimumab had lower disease activity as well as better physical function and quality of life in comparison to patients starting another drug. A higher proportion of patients starting infliximab had a history of extra-articular manifestations. Drug dosage was more often escalated during follow-up in patients treated with infliximab than with subcutaneously administered agents. However, no significant differences in time up to drug discontinuation or dose escalation were observed in multiple adjusted analyses if treatment was initiated after 2009, when all 4 TNF inhibitors were available: hazard ratio for infliximab versus etanercept 1.16 (95% confidence interval 0.80; 1.67), p = 0.44, for golimumab versus etanercept 0.80 (0.58; 1.10), p = 0.17 and for adalimumab versus etanercept 0.93 (0.69; 1.26), p = 0.66. CONCLUSION: In axial spondyloarthritis, drug survival with standard doses of different TNF inhibitors is comparable.

Response to Tumor Necrosis Factor Inhibition in Male and Female Patients with Ankylosing Spondylitis: Data from a Swiss Cohort.

OBJECTIVE: To investigate sex differences in connection with the effectiveness of tumor necrosis factor inhibitors (TNFi) in patients with ankylosing spondylitis (AS). METHODS: A total of 440 patients with AS (294 men; 146 women) initiating a first TNFi in the prospective Swiss Clinical Quality Management Cohort were included. We evaluated the proportion of patients achieving the 20% and 40% improvement in the Assessment of Spondyloarthritis international Society criteria (ASAS20 and ASAS40) as well as Ankylosing Spondylitis Disease Activity Score (ASDAS) improvement and status scores at 1 year. Patients having discontinued TNFi were considered nonresponders. Logistic regression analyses were performed to adjust for important predictors of response. RESULTS: Compared to men, female patients had lower mean C-reactive protein levels, better spinal mobility, and more peripheral disease at the start. There was no sex disparity with regard to the ASDAS, the Bath Ankylosing Spondylitis Disease Activity and Functional indices, and the quality of life. At 1 year, 52% of women and 63% of men achieved an ASAS20 response (OR 0.63, 95% CI 0.37-1.07, p = 0.09). An inactive disease status (ASDAS < 1.3) was reached by 18% of women and 26% of men (OR 0.65, 95% CI 0.32-1.27, p = 0.22). These sex differences in response to TNFi were more pronounced in adjusted analyses (OR 0.34, 95% CI 0.16-0.71, p = 0.005 for ASAS20 and OR 0.10, 95% CI 0.03-0.31, p < 0.001 for ASDAS < 1.3) and confirmed for all the other outcomes assessed. CONCLUSION: In AS, fewer women respond to TNFi and women show a reduced response in comparison to men.

TNF blockers inhibit spinal radiographic progression in ankylosing spondylitis by reducing disease activity: results from the Swiss Clinical Quality Management cohort.

OBJECTIVES: To analyse the impact of tumour necrosis factor inhibitors (TNFis) on spinal radiographic progression in ankylosing spondylitis (AS). METHODS: Patients with AS in the Swiss Clinical Quality Management cohort with up to 10 years of follow-up and radiographic assessments every 2 years were included. Radiographs were scored by two readers according to the modified Stoke Ankylosing Spondylitis Spine Score (mSASSS) with known chronology. The relationship between TNFi use before a 2-year radiographic interval and progression within the interval was investigated using binomial generalised estimating equation models with adjustment for potential confounding and multiple imputation of missing values. Ankylosing Spondylitis Disease Activity Score (ASDAS) was regarded as mediating the effect of TNFi on progression and added to the model in a sensitivity analysis. RESULTS: A total of 432 patients with AS contributed to data for 616 radiographic intervals. Radiographic progression was defined as an increase in ≥2 mSASSS units in 2 years. Mean (SD) mSASSS increase was 0.9 (2.6) units in 2 years. Prior use of TNFi reduced the odds of progression by 50% (OR 0.50, 95% CI 0.28 to 0.88) in the multivariable analysis. While no direct effect of TNFi on progression was present in an analysis including time-varying ASDAS (OR 0.61, 95% CI 0.34 to 1.08), the indirect effect, via a reduction in ASDAS, was statistically significant (OR 0.75, 95% CI 0.59 to 0.97). CONCLUSION: TNFis are associated with a reduction of spinal radiographic progression in patients with AS. This effect seems mediated through the inhibiting effect of TNFi on disease activity.

Impact of obesity on the response to tumor necrosis factor inhibitors in axial spondyloarthritis.

BACKGROUND: Few studies have investigated the impact of obesity on the response to tumor necrosis factor inhibitors (TNFi) in patients with axial spondyloarthritis (axSpA). The aim of our study was to investigate the impact of different body mass index (BMI) categories on TNFi response in a large cohort of patients with axSpA. METHODS: Patients with axSpA within the Swiss Clinical Quality Management (SCQM) program were included in the current study if they fulfilled the Assessment in Spondyloarthritis International Society (ASAS) criteria for axSpA, started a first TNFi after recruitment, and had available BMI data as well as a baseline and follow-up visit at 1 year (±6 months). Patients were categorized according to BMI: normal (BMI 18.5 to <25), overweight (BMI 25-30), and obese (BMI >30). We evaluated the proportion of patients achieving the 40% improvement in ASAS criteria (ASAS40), as well as Ankylosing Spondylitis Disease Activity Score (ASDAS) improvement and status scores at 1 year. Patients having discontinued the TNFi were considered nonresponders. We controlled for age, sex, HLA-B27, axSpA type, BASDAI, BASMI, elevated C-reactive protein (CRP), current smoking, enthesitis, physical exercise, and co-medication with disease-modifying antirheumatic drugs, as well as with nonsteroidal anti-inflammatory drugs in multiple adjusted logistic regression analyses. RESULTS: A total of 624 axSpA patients starting a first TNFi were considered in the current study (332 patients of normal weight, 204 patients with overweight, and 88 obese patients). Obese individuals were older, had higher BASDAI levels, and had a more important impairment of physical function in comparison to patients of normal weight, while ASDAS and CRP levels were comparable between the three BMI groups. An ASAS40 response was reached by 44%, 34%, and 29% of patients of normal weight, overweight, and obesity, respectively (overall p = 0.02). Significantly lower odds ratios (ORs) for achieving ASAS40 response were found in adjusted analyses in obese patients versus patients with normal BMI (OR 0.27, 95% confidence interval (CI) 0.09-0.70). The respective adjusted ASAS40 OR in overweight versus normal weight patients was 0.62 (95% CI 0.24-1.14). Comparable results were found for the other outcomes assessed. CONCLUSIONS: Obesity is associated with significantly lower response rates to TNFi in patients with axSpA.

The Effect of Comedication With a Conventional Synthetic Disease-Modifying Antirheumatic Drug on Drug Retention and Clinical Effectiveness of Anti-Tumor Necrosis Factor Therapy in Patients With Axial Spondyloarthritis.

OBJECTIVE: To explore the effect of comedication with conventional synthetic disease-modifying antirheumatic drugs (DMARDs) on drug retention and clinical effectiveness of tumor necrosis factor inhibitors (TNFi) in patients with axial spondyloarthritis (SpA). METHODS: The study included all patients starting treatment with a TNFi in a large prospective cohort of axial SpA patients (Swiss Clinical Quality Management in axial SpA). Crude drug retention was analyzed using the Kaplan-Meier method, and in adjusted analyses, Cox proportional hazards regression was used to model TNFi discontinuation. We evaluated multiple disease activity measures and validated clinical response criteria over time. RESULTS: A total of 2,765 TNFi treatment courses were included from 1,914 patients with axial SpA, 20.4% in combination with a conventional synthetic DMARD. In unadjusted analyses, the monotherapy group had significantly shorter median TNFi retention time (32.7 months) compared to the cotherapy group (39.1 months) (P = 0.04). In multivariate adjusted analyses, the monotherapy group had significantly lower TNFi retention, with a hazard ratio (HR) of 1.17 (95% confidence interval [95% CI] 1.01-1.35). This effect was even larger when only infliximab-treated patients were considered, with an HR for monotherapy of 1.36 (95% CI 1.06-1.74). Clinical response rates were almost identical at 1 year, with a change in the Bath Ankylosing Spondylitis Disease Activity Index of -2.02 and -2.00 (P = 0.83) and a change in the Ankylosing Spondylitis Disease Activity Score using C-reactive protein of -1.14 and -1.12 (P = 0.45) in the monotherapy and cotherapy groups, respectively. CONCLUSION: We demonstrate an association between the combination of a TNFi with conventional synthetic DMARDs and improved drug retention in patients with axial SpA, particularly in the subgroup of patients with infliximab.

Does the reason for discontinuation of a first TNF inhibitor influence the effectiveness of a second TNF inhibitor in axial spondyloarthritis? Results from the Swiss Clinical Quality Management Cohort.

BACKGROUND: With regard to switching tumor necrosis factor inhibitors (TNFi) in axial spondyloarthritis (axSpA), conflicting results have been reported as to whether the effectiveness of a second TNFi depends on the reason for discontinuation of the first TNFi. METHODS: Patients with a clinical diagnosis of axSpA starting a second TNFi in the Swiss Clinical Quality Management cohort were included. Effectiveness of treatment at 1 year, as well as drug survival, was compared between subgroups having discontinued the first TNFi because of lack of response, adverse events (AEs), or other reasons. Lack of response was further divided into primary or secondary lack of response (PLR or SLR, respectively), depending on whether the first TNFi was stopped before or after 6 months of treatment. RESULTS: Among 632 patients with axSpA, median survival of a second TNFi was 1.1 years after PLR and 3.8 years after SLR (p = 0.003). At least moderate disease activity as defined by an Ankylosing Spondylitis Disease Activity Score using the erythrocyte sedimentation rate (ASDAS-ESR) <2.1 was achieved after 12 months by 11 %, 39 %, 26 %, and 39 % of patients who discontinued their first TNFi because of PLR, SLR, AEs, and other reasons, respectively (p = 0.01). Only 4 % of patients achieved an ASDAS-ESR inactive disease state after PLR, in comparison to 22 % of those after SLR. Similar results were demonstrated in patients fulfilling the Assessment of SpondyloArthritis international Society classification criteria for axSpA (n = 488): ASDAS-ESR <2.1 was achieved after 12 months by 9 %, 41 %, 29 %, and 39 % of patients who discontinued their first TNFi because of PLR, SLR, AEs, and other reasons, respectively (p = 0.01). CONCLUSIONS: The effectiveness of a second TNFi is significantly impaired in patients with axSpA after PLR to a first TNFi compared with SLR.

Impaired response to treatment with tumour necrosis factor α inhibitors in smokers with axial spondyloarthritis.

OBJECTIVES: To investigate the impact of smoking on the response to treatment with a first tumour necrosis factor inhibitor (TNFi) in patients with axial spondyloarthritis (axSpA) in a real-life cohort. METHODS: Patients fulfilling the Assessment of SpondyloArthritis international Society (ASAS) classification criteria for axSpA in the Swiss Clinical Quality Management Cohort were included in this study. The potential association between smoking status and differential response to TNFi in terms of the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and the Ankylosing Spondylitis Disease Activity Score (ASDAS) was analysed using multiple adjusted longitudinal mixed effect models. Binary response rates at 1 year were assessed with multiple adjusted logistic analyses. RESULTS: A first TNFi was initiated in 698 patients with axSpA with available smoking status and a baseline or follow-up BASDAI assessment, of which 490 (70%) had complete covariate data. In comparison to non-smokers, current smokers demonstrated significantly smaller reductions in BASDAI and ASDAS scores upon treatment with TNFi (0.75 BASDAI units and 0.69 ASDAS units less, p=0.005 and 0.001, respectively) for patients with elevated baseline C-reactive protein (CRP) level. This effect was numerically smaller in patients with normal CRP. The odds for reaching a 50% improvement in BASDAI response or the ASAS criteria for 40% improvement after 1 year were significantly lower in current smokers than in non-smokers (0.54, 95% CI 0.31 to 0.95, p=0.03 and 0.43, 95% CI 0.24 to 0.76, p=0.004, respectively). CONCLUSIONS: Current smoking is associated with an impaired response to TNFi in axSpA.

Treatment with tumor necrosis factor inhibitors in axial spondyloarthritis: comparison between private rheumatology practices and academic centers in a large observational cohort.

OBJECTIVE: To evaluate the initiation of and response to tumor necrosis factor (TNF) inhibitors for axial spondyloarthritis (axSpA) in private rheumatology practices versus academic centers. METHODS: We compared newly initiated TNF inhibition for axSpA in 363 patients enrolled in private practices with 100 patients recruited in 6 university hospitals within the Swiss Clinical Quality Management (SCQM) cohort. RESULTS: All patients had been treated with ≥ 1 nonsteroidal antiinflammatory drug and > 70% of patients had a baseline Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) ≥ 4 before anti-TNF agent initiation. The proportion of patients with nonradiographic axSpA (nr-axSpA) treated with TNF inhibitors was higher in hospitals versus private practices (30.4% vs 18.7%, p = 0.02). The burden of disease as assessed by patient-reported outcomes at baseline was slightly higher in the hospital setting. Mean levels (± SD) of the Ankylosing Spondylitis Disease Activity Score were, however, virtually identical in private practices and academic centers (3.4 ± 1.0 vs 3.4 ± 0.9, p = 0.68). An Assessment of SpondyloArthritis international Society (ASAS40) response at 1 year was reached for ankylosing spondylitis in 51.7% in private practices and 52.9% in university hospitals (p = 1.0) and for nr-axSpA in 27.5% versus 25.0%, respectively (p = 1.0). CONCLUSION: With the exception of a lower proportion of patients with nr-axSpA newly treated with anti-TNF agents in private practices in comparison to academic centers, adherence to ASAS treatment recommendations for TNF inhibition was equally high, and similar response rates to TNF blockers were achieved in both clinical settings.