FLT3 stop mutation increases FLT3 ligand level and risk of autoimmune thyroid disease.

Autoimmune thyroid disease is the most common autoimmune disease and is highly heritable1. Here, by using a genome-wide association study of 30,234 cases and 725,172 controls from Iceland and the UK Biobank, we find 99 sequence variants at 93 loci, of which 84 variants are previously unreported2-7. A low-frequency (1.36%) intronic variant in FLT3 (rs76428106-C) has the largest effect on risk of autoimmune thyroid disease (odds ratio (OR) = 1.46, P = 2.37 × 10-24). rs76428106-C is also associated with systemic lupus erythematosus (OR = 1.90, P = 6.46 × 10-4), rheumatoid factor and/or anti-CCP-positive rheumatoid arthritis (OR = 1.41, P = 4.31 × 10-4) and coeliac disease (OR = 1.62, P = 1.20 × 10-4). FLT3 encodes fms-related tyrosine kinase 3, a receptor that regulates haematopoietic progenitor and dendritic cells. RNA sequencing revealed that rs76428106-C generates a cryptic splice site, which introduces a stop codon in 30% of transcripts that are predicted to encode a truncated protein, which lacks its tyrosine kinase domains. Each copy of rs76428106-C doubles the plasma levels of the FTL3 ligand. Activating somatic mutations in FLT3 are associated with acute myeloid leukaemia8 with a poor prognosis and rs76428106-C also predisposes individuals to acute myeloid leukaemia (OR = 1.90, P = 5.40 × 10-3). Thus, a predicted loss-of-function germline mutation in FLT3 causes a reduction in full-length FLT3, with a compensatory increase in the levels of its ligand and an increased disease risk, similar to that of a gain-of-function mutation.

Association of rheumatoid factor, anti-citrullinated protein antibodies and shared epitope with clinical response to initial treatment in patients with early rheumatoid arthritis: data from a randomised controlled trial.

OBJECTIVES: To investigate whether rheumatoid factor (RF), anti-citrullinated protein antibodies (ACPAs) and shared epitope (SE) allele-related genetic markers associate with treatment response to abatacept, certolizumab pegol or tocilizumab versus active conventional treatment (ACT). METHODS: Patients with treatment-naïve early rheumatoid arthritis were randomised in the NORD-STAR trial to ACT, certolizumab pegol, abatacept or tocilizumab, all with methotrexate. Centralised laboratory analyses for ACPA, RF and SE were performed. Clinical Disease Activity Index remission was analysed longitudinally with logistic generalised estimating equations. Differences in treatment effect across RF, ACPA and SE subgroups were assessed with interaction terms at 24 and 48 weeks, adjusted for sex, country, age, body mass index, Disease Activity Score of 28 joints based on C-reactive protein and smoking. RESULTS: In total, 778 patients were included. At 24 weeks, abatacept treatment showed a better response than ACT in the RF and/or ACPA-positive subgroups, but this effect was not significantly different from the negative subgroups. By 48 weeks, abatacept treatment showed better response regardless of RF/ACPA status. No differences were found across RF, ACPA, SE allele, valine at amino acid position 11 or valine-arginine-alanine haplotype subgroups for any biological treatment at 48 weeks. CONCLUSIONS: Based on this randomised controlled trial, abatacept treatment was associated with a better response than ACT in the RF and/or ACPA-positive subgroup at 24 weeks, but this was no longer seen at 48 weeks; adding SE allele-related genetic markers did not strengthen the association. Moreover, ACPA, RF and SE allele-related genotypes were not, alone or in combination, associated with clinical responses of importance sufficiently strongly to warrant implementation in clinical practice. TRIAL REGISTRATION NUMBER: EudraCT 2011-004720-35; ClinicalTrials.gov NCT01491815.

Predictors of DAPSA28 remission in patients with psoriatic arthritis initiating a first TNF inhibitor: results from 13 European registries.

OBJECTIVES: In bio-naïve patients with PsA initiating a TNF inhibitor (TNFi), we aimed to identify baseline predictors of Disease Activity index for PsA in 28 joints (DAPSA28) remission (primary objective) and DAPSA28 moderate response at 6 months, as well as drug retention at 12 months across 13 European registries. METHODS: Baseline demographic and clinical characteristics were retrieved and the three outcomes investigated per registry and in pooled data, using logistic regression analyses on multiply imputed data. In the pooled cohort, selected predictors that were either consistently positive or negative across all three outcomes were defined as common predictors. RESULTS: In the pooled cohort (n = 13 369), 6-month proportions of remission, moderate response and 12-month drug retention were 25%, 34% and 63% in patients with available data (n = 6954, n = 5275 and n = 13 369, respectively). Five common baseline predictors of remission, moderate response and 12-month drug retention were identified across all three outcomes. The odds ratios (95% CIs) for DAPSA28 remission were: age, per year: 0.97 (0.96-0.98); disease duration, years (<2 years as reference): 2-3 years: 1.20 (0.89-1.60), 4-9 years: 1.42 (1.09-1.84), ≥10 years: 1.66 (1.26-2.20); men vs women: 1.85 (1.54-2.23); CRP of >10 vs ≤10 mg/l: 1.52 (1.22-1.89) and 1 mm increase in patient fatigue score: 0.99 (0.98-0.99). CONCLUSION: Baseline predictors of remission, response and adherence to TNFi therapy were identified, of which five were common for all three outcomes, indicating that the predictors emerging from our pooled cohort may be considered generalizable from country level to disease level.

Sex differences in patient-reported outcomes and the association with clinical factors in axial spondyloarthritis patients treated with tumour necrosis factor inhibitors.

OBJECTIVES: To investigate sex differences in patient-reported outcome measures (PROMs) among axSpA patients initiating their first TNFi and identify factors contributing to these disparities over the follow-up. METHODS: Data were included from 15 EuroSpA registries and consisted of axSpA patients initiating their first TNFi, with ≥2 measurements for each analysed PROM (BASDAI and BASFI, scale 0-100) taken at any time point. Linear mixed models were employed to analyse sex differences in PROMs over 24 months and to evaluate how baseline characteristics were related to the observed sex differences. RESULTS: We analysed 13 102 (38% women) in the BASDAI analyses and 10 623 (38% women) in the BASFI analyses. At follow-up, mean sex differences in BASDAI increased from 4.3 units at baseline (95% CI, 3.5-5.1)-8.0 (7.2-8.8) at 6 months, and in BASFI from 2.2 (1.4-3.1)-4.6 (3.6-5.5), with consistently worse scores in women. Baseline characteristics could not substantially account for the observed sex differences over time; however, the magnitude of the sex differences was reduced by HLA-B27 positivity, longer disease duration, and increased CRP levels, but increased by TNFi initiation in later years and peripheral arthritis. CONCLUSION: In axSpA patients initiating their first TNFi, baseline sex differences in BASDAI and BASFI increased two-fold after 6 months of treatment and persisted thereafter, with worse scores in women. Several baseline characteristics moderated the sex differences, though none could fully account for them. These findings improve our understanding of sex differences and underscore their importance in axSpA.

Interstitial Lung Disease in Patients With Rheumatoid Arthritis or Psoriatic Arthritis Initiating Biologics and Controls: Data From 5 Nordic Registries.

OBJECTIVE: Interstitial lung disease (ILD) is one of the most common pulmonary manifestations of rheumatoid arthritis (RA), but its prevalence has not been investigated in psoriatic arthritis (PsA). The role of methotrexate (MTX) in ILD development remains under debate. This study (1) compares the incidences of ILD in patients with RA or PsA initiating a first biologic disease-modifying antirheumatic drug (bDMARD) to that in the general population, and (2) investigates the role of MTX comedication on ILD incidence. METHODS: Patients were identified in 5 rheumatology registries. Demographics, MTX use, and disease activity were retrieved. Matched subjects from the general population were available from 4 countries. Incidence of ILD during follow-up of up to 5 years was assessed through national patient registries. Subjects with prior ILD were excluded. Adjusted hazard ratios (HRs) were calculated for ILD incidence in patients vs the general population, and for MTX users vs nonusers. RESULTS: During follow-up of 29,478 patients with RA and 10,919 patients with PsA initiating a first bDMARD and 362,087 population subjects, 225, 23, and 251 cases of ILD were identified, respectively. HRs for ILD (vs population subjects) were 9.7 (95% CI 7.97-11.91) in RA and 4.4 (95% CI 2.83-6.97) in PsA. HRs for ILD with MTX comedication (vs nonuse) were 1.0 (95% CI 0.72-1.25) in RA and 0.9 (95% CI 0.38-2.05) in PsA. CONCLUSION: Among patients with RA and PsA initiating a bDMARD, the risk of ILD was higher than in the general population, and was highest in RA. MTX comedication was not a risk determinant for ILD.

Patient-Reported Outcomes (PROs) and PRO Remission Rates in 12,262 Biologic-Naïve Patients With Psoriatic Arthritis Treated With Tumor Necrosis Factor Inhibitors in Routine Care.

OBJECTIVE: To evaluate patient-reported outcomes (PROs) after initiation of tumor necrosis factor inhibitor (TNFi) treatment in European real-world patients with psoriatic arthritis (PsA). Further, to investigate PRO remission rates across treatment courses, registries, disease duration, sex, and age at disease onset. METHODS: Visual analog scale or numerical rating scale scores for pain, fatigue, patient global assessment (PtGA), and the Health Assessment Questionnaire-Disability Index (HAQ-DI) from 12,262 patients with PsA initiating a TNFi in 13 registries were pooled. PRO remission rates (pain ≤ 1, fatigue ≤ 2, PtGA ≤ 2, and HAQ-DI ≤ 0.5) were calculated for patients still on the treatment. RESULTS: For the first TNFi, median pain score was reduced by approximately 50%, from 6 to 3, 3, and 2; as were fatigue scores, from 6 to 4, 4, and 3; PtGA scores, from 6 to 3, 3, and 2; and HAQ-DI scores, from 0.9 to 0.5, 0.5, and 0.4 at baseline, 6, 12, and 24 months, respectively. Six-month Lund Efficacy Index (LUNDEX)-adjusted remission rates for pain, fatigue, PtGA, and HAQ-DI scores were 24%, 31%, 36%, and 43% (first TNFi); 14%, 19%, 23%, and 29% (second TNFi); and 9%, 14%, 17%, and 20% (third TNFi), respectively. For biologic-naïve patients with disease duration < 5 years, 6-month LUNDEX-adjusted remission rates for pain, fatigue, PtGA, and HAQ-DI scores were 22%, 28%, 33%, and 42%, respectively. Corresponding rates for patients with disease duration > 10 years were 27%, 32%, 41%, and 43%, respectively. Remission rates were 33%, 40%, 45%, and 56% for men and 17%, 23%, 24%, and 32% for women, respectively. For patients aged < 45 years at diagnosis, 6-month LUNDEX-adjusted remission rate for pain was 29% vs 18% for patients ≥ 45 years. CONCLUSION: In 12,262 biologic-naïve patients with PsA, 6 months of treatment with a TNFi reduced pain by approximately 50%. Marked differences in PRO remission rates across treatment courses, registries, disease duration, sex, and age at onset of disease were observed, emphasizing the potential influence of factors other than disease activity on PROs.

Uptake and effectiveness of newer biologic and targeted synthetic disease-modifying antirheumatic drugs in psoriatic arthritis: results from five Nordic biologics registries.

BACKGROUND: We aimed to describe the uptake of newer biologic or targeted synthetic disease-modifying antirheumatic drugs (b/tsDMARDs) in psoriatic arthritis (PsA) in the Nordic countries and to compare their retention and effectiveness. METHODS: Patients with PsA starting a b/tsDMARD in 2012-2020 in five Nordic rheumatology registers were included. Uptake and patient characteristics were described, with comorbidities identified from linkages to national patient registries. One-year retention and 6-month effectiveness (proportions achieving low disease activity (LDA) on the Disease Activity Index for PSoriatic Arthritis based on 28-joint evaluation) for the newer b/tsDMARDs (abatacept/apremilast/ixekizumab/secukinumab/tofacitinib/ustekinumab) were compared with adalimumab through adjusted regression models stratified by treatment course (first, second/third, and fourth or more). RESULTS: In total, 5659 treatment courses with adalimumab (56% biologic-naïve) and 4767 courses with a newer b/tsDMARD (21% biologic-naïve) were included. The uptake of newer b/tsDMARDs increased from 2014 and plateaued in 2018. Patient characteristics appeared similar across treatments at treatment start. Adalimumab was more often used as the first course and newer b/tsDMARDs more often in biologic-experienced patients. Used as a second/third b/tsDMARD, the retention rate and the proportion achieving LDA were significantly better for adalimumab (rate 65%, proportion 59%) compared with abatacept (45%, 37%), apremilast (43%, 35%), ixekizumab (LDA only, 40%) and ustekinumab (LDA only, 40%), but not significantly different from other b/tsDMARDs. CONCLUSION: Uptake of newer b/tsDMARDs occurred mainly in biologic-experienced patients. Regardless of mode of action, only a minority of patients starting a second or later b/tsDMARD course remained on drug and achieved LDA. Superior outcomes for adalimumab indicate that the positioning of newer b/tsDMARDs in the PsA treatment algorithm remains to be established.

Certolizumab pegol, abatacept, tocilizumab or active conventional treatment in early rheumatoid arthritis: 48-week clinical and radiographic results of the investigator-initiated randomised controlled NORD-STAR trial.

BACKGROUND: The optimal first-line treatment in early rheumatoid arthritis (RA) is debated. We compared clinical and radiographic outcomes of active conventional therapy with each of three biological treatments with different modes of action. METHODS: Investigator-initiated, randomised, blinded-assessor study. Patients with treatment-naïve early RA with moderate-severe disease activity were randomised 1:1:1:1 to methotrexate combined with (1) active conventional therapy: oral prednisolone (tapered quickly, discontinued at week 36) or sulfasalazine, hydroxychloroquine and intra-articular glucocorticoid injections in swollen joints; (2) certolizumab pegol; (3) abatacept or (4) tocilizumab. Coprimary endpoints were week 48 Clinical Disease Activity Index (CDAI) remission (CDAI ≤2.8) and change in radiographic van der Heijde-modified Sharp Score, estimated using logistic regression and analysis of covariance, adjusted for sex, anticitrullinated protein antibody status and country. Bonferroni's and Dunnet's procedures adjusted for multiple testing (significance level: 0.025). RESULTS: Eight hundred and twelve patients were randomised. Adjusted CDAI remission rates at week 48 were: 59.3% (abatacept), 52.3% (certolizumab), 51.9% (tocilizumab) and 39.2% (active conventional therapy). Compared with active conventional therapy, CDAI remission rates were significantly higher for abatacept (adjusted difference +20.1%, p<0.001) and certolizumab (+13.1%, p=0.021), but not for tocilizumab (+12.7%, p=0.030). Key secondary clinical outcomes were consistently better in biological groups. Radiographic progression was low, without group differences.The proportions of patients with serious adverse events were abatacept, 8.3%; certolizumab, 12.4%; tocilizumab, 9.2%; and active conventional therapy, 10.7%. CONCLUSIONS: Compared with active conventional therapy, clinical remission rates were superior for abatacept and certolizumab pegol, but not for tocilizumab. Radiographic progression was low and similar between treatments. TRIAL REGISTRATION NUMBER: NCT01491815.

Strong site-specific association of pharyngeal cultures with the onset of psoriatic arthritis and psoriasis, regardless of pathogen.

OBJECTIVES: The objective of this study was to evaluate any association between culture site / culture result / pathogen and incident PsA or psoriasis. METHODS: Records of all samples sent for culture from a large population during a 3-year period were linked with nationwide registry data on diagnoses and death over a 15-year period. The main outcomes of interest were incident diagnoses of PsA and psoriasis, defined by International Classification of Diseases (ICD) codes. The effect of culture site, culture result (positive vs negative), and pathogen (Streptococcus vs negative culture) on the risk of developing PsA and psoriasis was calculated using Cox proportional hazards models adjusted for age and gender. RESULTS: A total of 313 235 bacterial cultures from 128 982 individuals were analysed. Comparing individuals with pharyngeal cultures to those with urine cultures, the hazard ratio for incident PsA was 8.78 [95% confidence interval (CI) 3.23, 23.91] and for incident psoriasis it was 8.00 (95% CI 5.28, 12.12). Most of the risk was concentrated in the first 50 days after the culture date. Increased risk was also found when comparing individuals with cultures from the pharynx with those with cultures from the nasopharynx and blood. An association with streptococci was not found, neither in the pharynx nor at any other site. A positive bacterial culture from any site was associated with reduced risk for both PsA and psoriasis. CONCLUSION: There is a strong site-specific association between pharyngeal culture samples and an increased risk of PsA and psoriasis, regardless of the pathogen. This may indicate that the site of infection, rather than the pathogen, is associated with increased risk.

Is the risk of infection higher during treatment with secukinumab than with TNF inhibitors? An observational study from the Nordic countries.

OBJECTIVES: The positioning of secukinumab in the treatment of axial SpA (axSpA) and PsA is debated, partly due to a limited understanding of the comparative safety of the available treatments. We aimed to assess the risk of the key safety outcome infections during treatment with secukinumab and TNF inhibitors (TNFi). METHODS: Patients with SpA and PsA starting secukinumab or TNFi year 2015 through 2018 were identified in four Nordic rheumatology registers. The first hospitalized infection during the first year of treatment was identified through linkage to national registers. Incidence rates (IRs) with 95% CIs per 100 patient-years were calculated. Adjusted hazard ratios were estimated through Cox regression, with secukinumab as the reference. Several sensitivity analyses were performed to investigate confounding by indication. RESULTS: Among 7708 patients with SpA and 5760 patients with PsA, we identified 16 229 treatment courses of TNFi (53% bionaïve) and 1948 with secukinumab (11% bionaïve). For secukinumab, the first-year risk of hospitalized infection was 3.5% (IR 5.0; 3.9-6.3), compared with 1.7% (IR 2.3; 1.7-3.0) during 3201 courses with adalimumab, with the IRs for other TNFi lying in between these values. The adjusted HR for adalimumab, compared with secukinumab, was 0.58 (0.39-0.85). In sensitivity analyses, the difference from secukinumab was somewhat attenuated and in some analyses no longer statistically significant. CONCLUSION: When used according to clinical practice in the Nordic countries, the observed first-year absolute risk of hospitalized infection was doubled for secukinumab compared with adalimumab. This excess risk seemed largely explained by confounding by indication.

Second and third TNF inhibitors in European patients with axial spondyloarthritis: Effectiveness and impact of the reason for switching.

OBJECTIVE: To investigate real-world effectiveness of tumor necrosis factor inhibitors (TNFi) in patients with axial spondyloarthritis (axSpA) and the association with 1) treatment line (second and third TNFi-series) and 2) reason for withdrawal from the preceding TNFi (lack of efficacy (LOE) versus adverse events (AE)). METHODS: Prospectively collected routine care data from 12 European registries were pooled. Rates for 12-month drug retention and 6-month remission (Ankylosing Spondylitis Disease Activity Score C-reactive protein inactive disease (ASDAS-ID)) were assessed in second and third TNFi-series and stratified by withdrawal reason. RESULTS: We included 8254 s and 2939 third TNFi-series; 12-month drug retention rates were similar (71%). Six-month ASDAS-ID rates were higher for the second (23%) than third TNFi (16%). Twelve-month drug retention rates for patients withdrawing from the preceding TNFi due to AE versus LOE were similar for the second (68% and 67%) and third TNFi (both 68%), while for the second TNFi, rates were lower in primary than secondary non-responders (LOE < 26 versus ≥26 weeks) (58% versus 71%, p< 0.001). Six-month ASDAS-ID rates for the second TNFi were higher if the withdrawal reason was AE (27%) versus LOE (17%), p< 0.001, while similar for the third TNFi (19% versus 13%, p= 0.20). CONCLUSION: A similar proportion of axSpA patients remained on a second and third TNFi after one year, but with low remission rates for the third TNFi. Remission rates on the second TNFi (but not the third) were higher if the withdrawal reason from the preceding TNFi was AE versus LOE.

Infliximab-induced liver injury: Clinical phenotypes, autoimmunity and the role of corticosteroid treatment.

BACKGROUND & AIMS: Infliximab has been associated with drug-induced liver injury (DILI), particularly drug-induced autoimmune hepatitis (DIAIH). DIAIH is commonly treated with corticosteroids, but there is limited data on the efficacy of corticosteroids in infliximab-induced DILI. METHODS: Patients were included for assessment if they had been treated with infliximab between 2009-2020 in Iceland and had developed elevated liver tests. Other specific etiologies of liver enzyme elevations were excluded. Patients treated with corticosteroids were compared to patients not receiving corticosteroids. RESULTS: A total of 36 patients with infliximab-induced DILI were identified: median age was 46 years (IQR 32-54) and 28 (78%) were female. Type of liver injury was predominantly hepatocellular (64%). Median peak liver enzymes were: alanine aminotransferase (ALT) 393 (328-695) U/L, aspartate aminotransferase 283 (158-564) U/L, alkaline phosphatase 116 (83-205) U/L, and bilirubin (10-20) 13 µmol/L. A total of 25 (69%) were positive for anti-nuclear antibody and/or had elevated IgG. Corticosteroids were initiated in 17 (47%). Median time from onset of liver injury to peak ALT value was longer in patients treated with corticosteroids, 22 (12-59) vs. 0 (0-3) days (p = 0.001). Time from peak ALT to normalization of liver enzymes was 45 days in the corticosteroid group vs. 77 days in others (p = 0.062). Corticosteroids were tapered in all patients, with no cases of relapse during the follow-up period of 1,245 (820-2,698) days. Overall 75% received another biologic, mostly adalimumab, without evidence of liver injury. CONCLUSION: Approximately half of patients with infliximab-induced liver injury had slow improvement in ALT despite cessation of therapy and were treated with corticosteroids. Treatment response was good with prompt resolution of liver test abnormalities. Relapse of liver injury was not observed after tapering of corticosteroids despite prolonged follow-up and no patients developed DILI due to a second biologic. LAY SUMMARY: A rare side effect of infliximab, a biologic medicine used to treat multiple inflammatory diseases, is liver injury and liver inflammation. Steroid treatment has been used in some patients with liver injury caused by infliximab, but there have been few studies supporting this treatment. In this study of 36 patients with infliximab-induced liver injury, approximately half of patients were treated with steroids and the results suggest that patients receiving steroids recover more quickly.

Short-term, intermediate-term and long-term risks of acute coronary syndrome in cohorts of patients with RA starting biologic DMARDs: results from four Nordic countries.

OBJECTIVES: To compare the 1-year, 2-year and 5-year incidences of acute coronary syndrome (ACS) in patients with rheumatoid arthritis (RA) starting any of the biologic disease-modifying antirheumatic drugs (bDMARDs) currently available in clinical practice and to anchor these results with a general population comparator. METHODS: Observational cohort study, with patients from Denmark, Finland, Norway and Sweden starting a bDMARD during 2008-2017. Time to first ACS was identified through register linkages. We calculated the 1-year, 2-year and 5-year incidence rates (IR) (on drug and ever since treatment start) and used Cox regression (HRs) to compare ACS incidences across treatments taking ACS risk factors into account. Analyses were further performed separately in subgroups defined by age, number of previous bDMARDs and history of cardiovascular disease. We also compared ACS incidences to an individually matched general population cohort. RESULTS: 24 083 patients (75% women, mean age 56 years) contributing 40 850 treatment courses were included. During the maximum (5 years) follow-up (141 257 person-years (pyrs)), 780 ACS events occurred (crude IR 5.5 per 1000 pyrs). Overall, the incidence of ACS in RA was 80% higher than that in the general population. For all bDMARDs and follow-up definitions, HRs were close to 1 (etanercept as reference) with the exception of the 5-year risk window, where signals for abatacept, infliximab and rituximab were noted. CONCLUSION: The rate of ACS among patients with RA initiating bDMARDs remains elevated compared with the general population. As used in routine care, the short-term, intermediate-term and longer-term risks of ACS vary little across individual bDMARDs.

Pregnancy outcomes in relation to disease activity and anti-rheumatic treatment strategies in women with rheumatoid arthritis: a matched cohort study from Sweden and Denmark.

OBJECTIVES: To explore the association of maternal RA to pregnancy outcomes, especially preterm birth (PTB) and small for gestational age (SGA), in relation to disease activity and anti-rheumatic treatment before and during pregnancy. METHODS: By linking prospective clinical rheumatology registers (CRR) in Sweden (the Swedish Rheumatology Quality Register, SRQ) and Denmark (the Danish clinical quality register, DANBIO) with medical birth registers, we identified 1739 RA-pregnancies and 17 390 control-pregnancies (matched 1:10 on maternal age, birth year, parity) with delivery 2006-18. Disease activity (DAS28, CRP, HAQ score) and anti-rheumatic treatment 9 months before and during pregnancy were identified through CRR and prescribed drug registers. Using logistic regression, we estimated adjusted odds ratios (aOR) with 95% CI for PTB and SGA overall and stratified by disease activity and anti-rheumatic treatment before and during pregnancy, adjusting for maternal characteristics. RESULTS: We found increased aOR of PTB [1.92 (1.56-2.35)] and SGA [1.93 (1.45-2.57)] in RA-pregnancies vs control-pregnancies. For RA-pregnancies with DAS28-CRP ≥4.1 vs <3.2 during pregnancy, aOR was 3.38 (1.52-7.55) for PTB and 3.90 (1.46-10.4) for SGA. Use of oral CS (yes/no) during pregnancy resulted in an aOR of 2.11 (0.94-4.74) for PTB. The corresponding figure for biologics was 1.38 (0.66-2.89). Combination therapy, including biologics before pregnancy, was a marker of increased risk of both PTB and SGA. CONCLUSION: During pregnancy, disease activity rather than treatment seems to be the most important risk factor for PTB and SGA in RA. Women with RA should be carefully monitored during pregnancy, especially if they have moderate to high disease activity or/and are treated with extensive anti-rheumatic treatment.

Do patient-reported measures of disease activity in rheumatoid arthritis vary between countries? Results from a Nordic collaboration.

OBJECTIVES: To investigate whether patient-reported outcomes vary across countries and are influenced by cultural/contextual factors. Specifically, we aimed to assess inter-country differences in tender joint count (TJC), pain and patient's global health assessment (PGA), and their impact on disease activity (DAS28-CRP) in RA patients from five Nordic countries. METHODS: We collected data (baseline, 3- and 12-months) from rheumatology registers in the five countries comprising RA patients starting a first ever MTX or a first ever TNF inhibitor (TNFi). In order to assess the role of context (=country), we separately modelled TJC, pain and PGA as functions of objective variables (CRP, swollen joint count, age, sex, calendar period and disease duration) with linear models. Analyses were performed at each time point and for both treatments. We further assessed the impact of inter-country differences on DAS28-CRP. RESULTS: A total of 27 645 RA patients started MTX and 19 733 started a TNFi. Crude inter-country differences at MTX start amounted to up to 4 points (28 points scale) for TJC, 10 and 27 points (0-100 scale) for pain and PGA, respectively. Corresponding numbers at TNFi start were 3 (TJC), 27 (pain) and 24 (PGA) points. All differences were reduced at 3- and 12-months, and attenuated when adjusting for the objective variables. The variation in predicted DAS28-CRP across countries amounted to <0.5 units. CONCLUSIONS: Inter-country differences in TJC, pain and PGA are greater than expected based on differences in objective measures, but have a small clinical impact on DAS28-CRP across countries.

The occurrence of multiple treatment switches in axial spondyloarthritis. Results from five Nordic rheumatology registries.

OBJECTIVES: In axial spondyloarthritis (axSpA), switching between multiple biologic or targeted synthetic (b/ts-) DMARDs might indicate difficult-to-treat disease. We aimed to explore the occurrence of multiple switching in routine care axSpA patients using various definitions, and to identify associated clinical characteristics upon start of first b/tsDMARD (baseline). METHODS: Observational cohort study including patients with axSpA starting a first-ever b/tsDMARD 2009-2018 based on data from five biologic registries (Denmark/Sweden/Finland/Norway/Iceland). Comorbidities and extra-articular manifestations were identified through linkage to national registries. Multi-switching was defined in overlapping categories according to b/tsDMARD treatment history: treatment with ≥3, ≥4 or ≥5 b/tsDMARDs during follow-up. We explored the cumulative incidence of patients becoming multi-switchers with ≥3 b/tsDMARDs stratified by calendar-period (2009-2011, 2012-2013, 2014-2015, 2016-2018). In the subgroup of patients starting a first b/tsDMARD 2009-2015, baseline characteristics associated with multi-switching (within 3 years' follow-up) were explored using multiple logistic regression analyses. RESULTS: Among 8398 patients included, 6056 patients (63% male, median age 42 years) started a first b/tsDMARD in 2009-2015, whereof proportions treated with ≥3, ≥4 or ≥5 b/tsDMARDs within 3 years' follow-up were 8%, 3% and 1%, respectively. Calendar-period did not affect the cumulative incidence of multi-switching. Baseline characteristics associated with multi-switching (≥3 b/tsDMARDs) were female gender, shorter disease duration, higher patient global score, comorbidities and having psoriasis but not uveitis. CONCLUSION: In this large Nordic observational cohort of axSpA patients, multiple switching was frequent with no apparent time-trend. Clinical associated factors included gender, but also previous comorbidities and extra-articular manifestations illustrating the ongoing challenge of treating this patient group.

European bio-naïve spondyloarthritis patients initiating TNF inhibitor: 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 TNF 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.

The impact of a csDMARD in combination with a TNF inhibitor on drug retention and clinical remission in axial spondyloarthritis.

OBJECTIVES: Many axial spondylarthritis (axSpA) patients receive a conventional synthetic DMARD (csDMARD) in combination with a TNF inhibitor (TNFi). However, the value of this co-therapy remains unclear. The objectives were to describe the characteristics of axSpA patients initiating a first TNFi as monotherapy compared with co-therapy with csDMARD, to compare one-year TNFi retention and remission rates, and to explore the impact of peripheral arthritis. METHODS: Data was collected from 13 European registries. One-year outcomes included TNFi retention and hazard ratios (HR) for discontinuation with 95% CIs. Logistic regression was performed with adjusted odds ratios (OR) of achieving remission (Ankylosing Spondylitis Disease Activity Score (ASDAS)-CRP < 1.3 and/or BASDAI < 2) and stratified by treatment. Inter-registry heterogeneity was assessed using random-effect meta-analyses, combined results were presented when heterogeneity was not significant. Peripheral arthritis was defined as ≥1 swollen joint at baseline (=TNFi start). RESULTS: Amongst 24 171 axSpA patients, 32% received csDMARD co-therapy (range across countries: 13.5% to 71.2%). The co-therapy group had more baseline peripheral arthritis and higher CRP than the monotherapy group. One-year TNFi-retention rates (95% CI): 79% (78, 79%) for TNFi monotherapy vs 82% (81, 83%) with co-therapy (P < 0.001). Remission was obtained in 20% on monotherapy and 22% on co-therapy (P < 0.001); adjusted OR of 1.16 (1.07, 1.25). Remission rates at 12 months were similar in patients with/without peripheral arthritis. CONCLUSION: This large European study of axial SpA patients showed similar one-year treatment outcomes for TNFi monotherapy and csDMARD co-therapy, although considerable heterogeneity across countries limited the identification of certain subgroups (e.g. peripheral arthritis) that may benefit from co-therapy.

Resolution of Th/Tc17-driven inflammation during anti-TNFα treatment of rheumatoid arthritis reveals a unique immune biomarker profiling pattern.

Rheumatoid arthritis (RA) is a chronic multisystem disease with a complex immunopathology. Its inflammatory state is dominated by pro-inflammatory cytokines such as TNFα and activated Th1/Th17. Only proportion of patients achieve clinical remission despite potent biologics targeting these pathways. This study investigated the resolution of inflammation in RA patients (naïve for biologics) receiving TNFα inhibitors (TNFi) and evaluated the biological mechanisms behind treatment response and assessed them using clinical scoring systems. The majority showed a good clinical response after six months (6M) and a significant drop in DAS28-CRP (P ≤ .002), CDAI (P ≤ .0001) and RheumXpert (P ≤ .0001). Before treatment, the patients demonstrated a chronic innate and adaptive inflammatory state. The improved clinical condition was reflected with a decrease in Th17/Tc17 (P ≤ .05) and an increase in Tregs after 6M (P ≤ .05). Using a logistic regression model on serum data, IL-6, IL-18, IL-21, IL-22, IFNγ and TNFα were identified as the main contributing biomarkers in the chronic inflammatory state of RA. A specific test score (STS) was defined and converted to a single cytokine composite test score (CCTS), which showed the disease outcome on a scale 0-100, providing sensitivity and specificity of ≥90%. Thus, the immunological complexity in RA is driven by a complex interplay of pro-inflammatory cytokines and effector T-cell response dominated by Th17/Tc17. In addition, the resolution of inflammation could be linked to a partially Treg-driven homeostatic innate immune response. Therefore, a more complex therapeutic approach against the above markers might be of value to obtain full clinical remission in the future.

Blood chemokine levels are markers of disease activity but not predictors of remission in early rheumatoid arthritis.

OBJECTIVES: In early rheumatoid arthritis (eRA) plasma levels of specific chemokines have been shown to correlate with disease activity. However, it is unclear whether pre-treatment chemokine levels can predict disease remission at week 24, and it is not known how biological treatments with different modes of action affect plasma chemokine levels in patients with untreated eRA. METHODS: This study included 347 Swedish patients with untreated eRA from the larger NORD-STAR randomised treatment trial. Here, eRA patients were treated with methotrexate combined with either prednisolone, anti-TNF (certolizumab-pegol), CTLA-4Ig (abatacept) or anti-IL6 receptor (tocilizumab). The primary clinical outcome was remission by clinical disease activity index (CDAI) defined as CDAI ≤ 2.8. Disease activity was assessed by CDAI, DAS28-ESR, DAS28-CRP, swollen joint counts, tender joint counts, ESR and CRP. The plasma concentrations of 14 chemokines were measured at baseline and after 24 weeks of treatment by bead-based immunoassay or ELISA. RESULTS: Baseline plasma concentrations of CXCL10, CXCL8, CXCL9, CXCL11, CXCL5 and CCL2 correlated with baseline disease activity measures. After 24 weeks of treatment, plasma levels of CXCL10, CXCL8, CXCL9, CXCL11 and CXCL13 decreased in all treatment groups except in patients treated with anti-IL6 receptor. In multivariate factor analysis, plasma chemokine levels at baseline could not differentiate patients who attained remission by week 24 from those who did not in any of the treatment groups. CONCLUSIONS: In patients with untreated eRA, plasma levels of several chemokines correlate with disease activity at baseline but cannot predict remission after 24 weeks of treatment with methotrexate combined with prednisolone, anti­TNF, CTLA­4Ig or anti­IL6R.