Temporal trends in mortality in patients with rheumatoid arthritis: a Danish population-based matched cohort study.

OBJECTIVES: To investigate the 5-year all-cause mortality in patients with RA compared with the general population. METHODS: This was a nationwide population-based matched cohort study. RA patients diagnosed between 1996 and the end of 2015 were identified using administrative heath registries and followed until the end of 2020 allowing 5 years of follow-up. Patients with incident RA were matched 1:5 on year of birth and sex with non-RA individuals from the Danish general population. Time-to-event analyses were performed using the pseudo-observation approach. RESULTS: Compared with matched controls in 1996-2000, the risk difference for RA patients ranged from 3.5% (95% CI 2.7%, 4.4%) in 1996-2000 to -1.6% (95% CI -2.3%, -1.0%) in 2011-15, and the relative risk from 1.3 (95% CI 1.2, 1.4) in 1996-2000 to 0.9 (95% CI 0.8, 0.9) in 2011-15. The age-adjusted 5-year cumulative incidence proportion of death for a 60-year-old RA patient decreased from 8.1% (95% CI 7.3%, 8.9%) when diagnosed in 1996-2000 to 2.9% (95% CI 2.3%, 3.5%) in 2011-15, and for matched controls from 4.6% (95% CI 4.2%, 4.9%) to 2.1% (95% CI 1.9%, 2.4%). Excess mortality persisted in women with RA throughout the study period, while the mortality risk for men with RA in 2011-15 was similar to their matched controls. CONCLUSIONS: Enhanced improvement in mortality was found in RA patients compared with matched controls, but for sex-specific differences excess mortality was only persistent in women with RA.

Infliximab biosimilar-to-biosimilar switching in patients with inflammatory rheumatic disease: clinical outcomes in real-world patients from the DANBIO registry.

OBJECTIVE: Successful uptake of biosimilars in rheumatology is limited by lack of real-world evidence regarding effectiveness of biosimilar-to-biosimilar switching. We investigated infliximab biosimilars CT-P13-to-GP1111 switching among patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA) and axial spondyloarthritis (AxSpA). METHODS: Observational cohort study from the DANBIO registry. Patients were classified as originator-naïve or originator-experienced. Retention rates of 1-year GP1111 treatment were explored (Kaplan-Meier). We identified baseline factors (at the time of switch) associated with withdrawal of GP1111 (multivariable Cox-regression analyses with HRs including originator treatment history). Changes in subjective and objective measures of disease activity 4 months before and after the switch were assessed in individual patients. RESULTS: Of 1605 patients (685 RA, 314 PsA and 606 AxSpA, median disease duration was 9 years, 37% in Clinical Disease Activity Index/Ankylosing Spondylitis Disease Activity Score remission), 1171 were originator-naïve. Retention rates at 1-year were 83% (95% CI: 81% to 85%) and 92% (95% CI: 90% to 95%) for the originator-naïve and originator-experienced, respectively. GP1111 retention rates were higher in originator-experienced compared to originator-naïve with RA (HR=0.4 (95% CI: 0.2 to 0.7)) and PsA (HR=0.2 (95% CI: 0.1 to 0.8)), but not significantly for AxSpA: HR=0.6 (95% CI: 0.3 to 1.2). Lower disease activity was associated with higher retention. Changes in disease activity preswitch and postswitch were close to zero. CONCLUSION: This real-world observational study of more than 1600 patients with inflammatory arthritis showed high 1-year retention following a nationwide infliximab biosimilar-to-biosimilar switch. Retention was higher in originator-experienced and in patients with low disease activity, suggesting outcomes to be affected by patient-related rather than drug-related factors.

Multiomics analysis of rheumatoid arthritis yields sequence variants that have large effects on risk of the seropositive subset.

OBJECTIVES: To find causal genes for rheumatoid arthritis (RA) and its seropositive (RF and/or ACPA positive) and seronegative subsets. METHODS: We performed a genome-wide association study (GWAS) of 31 313 RA cases (68% seropositive) and ~1 million controls from Northwestern Europe. We searched for causal genes outside the HLA-locus through effect on coding, mRNA expression in several tissues and/or levels of plasma proteins (SomaScan) and did network analysis (Qiagen). RESULTS: We found 25 sequence variants for RA overall, 33 for seropositive and 2 for seronegative RA, altogether 37 sequence variants at 34 non-HLA loci, of which 15 are novel. Genomic, transcriptomic and proteomic analysis of these yielded 25 causal genes in seropositive RA and additional two overall. Most encode proteins in the network of interferon-alpha/beta and IL-12/23 that signal through the JAK/STAT-pathway. Highlighting those with largest effect on seropositive RA, a rare missense variant in STAT4 (rs140675301-A) that is independent of reported non-coding STAT4-variants, increases the risk of seropositive RA 2.27-fold (p=2.1×10-9), more than the rs2476601-A missense variant in PTPN22 (OR=1.59, p=1.3×10-160). STAT4 rs140675301-A replaces hydrophilic glutamic acid with hydrophobic valine (Glu128Val) in a conserved, surface-exposed loop. A stop-mutation (rs76428106-C) in FLT3 increases seropositive RA risk (OR=1.35, p=6.6×10-11). Independent missense variants in TYK2 (rs34536443-C, rs12720356-C, rs35018800-A, latter two novel) associate with decreased risk of seropositive RA (ORs=0.63-0.87, p=10-9-10-27) and decreased plasma levels of interferon-alpha/beta receptor 1 that signals through TYK2/JAK1/STAT4. CONCLUSION: Sequence variants pointing to causal genes in the JAK/STAT pathway have largest effect on seropositive RA, while associations with seronegative RA remain scarce.

Smoking associates with distinct clinical phenotypes in patients with systemic lupus erythematosus: a nationwide Danish cross-sectional study.

OBJECTIVES: SLE displays large clinical heterogeneity that beyond genetic factors may be determined by environmental exposures. In this Danish nationwide study, we aimed to determine if clinical subsets of SLE were associated with smoking history. METHODS: At each of six participating centres, incident or prevalent inpatients and outpatients with SLE were consecutively included. Manifestations forming the basis of SLE classification were registered in an electronic chart system. Patients also provided questionnaire-based data on environmental exposures, including smoking history. Hierarchical cluster analysis was conducted to determine and characterise subsets of patients with similar traits of disease manifestations. Levels of smoking exposure by pack-years were correlated to the identified SLE subsets, as well as discrete SLE manifestations. RESULTS: The cohort consisted of 485 patients (88% women and 92% Caucasian) with SLE of which 51% were ever smokers. Common disease manifestations comprised non-erosive arthritis (81%), malar rash (57%), lymphopenia (55%), photosensitivity (50%) and persistent proteinuria (41%). We identified three distinct phenotypic clusters characterised by their preponderance of (A) neurological, serosal and mucosal involvement; (B) renal, haematological and immunological disorders; and (C) acute and chronic skin manifestations. Cluster B was the youngest and had the lowest level of smoking exposure. Age-adjusted regression analyses showed that compared with never smokers a smoking history of >20 pack-years was associated with neurological disorder (OR=3.16), discoid rash (OR=2.22), photosensitivity (OR=2.19) and inversely with haematological disorder (OR=0.40), renal disorder (OR=0.40) and non-erosive arthritis (OR=0.45), p<0.05 for all. CONCLUSIONS: Our findings support that SLE presents in varying clinical phenotypes and suggest that they may have differentiated associations with smoking history.

Patients with severe gout treated in mixed settings.

INTRODUCTION We aimed to investigate whether patients with a definite gout diagnosis who were treated in mixed real-life settings (various hospital departments or general practice) followed treatment recommendations. METHODS We included all patients in the hospital's uptake area in 2015-2017 who had been diagnosed with gout after microscopy findings of urate crystals. Data regarding comorbidities and indications for urate-lowering therapy (ULT) were collected. The criteria for treatment success were a p-urate level less-than 6 mg/dl (less-than 0.36 mmol/l) or less-than 5 mg/dl (less-than 0.30 mmol/l) if tophi were present. All patients were followed up for 24 months. RESULTS The study included 100 patients with a median age of 70 years, and 82% of patients were males. An indication for ULT was present in 99 patients and initiated in 79 patients. Fourteen of these 99 patients died within one year. For the remaining 85 patients, p-urate was measured, and the target was reached by 22 (26%) patients, not reached by 33 (39%) patients and not measured in 30 (35%) patients. Treatment success was positively associated with a written treatment plan in the rheumatology record after microscopy, initiation of ULT in the clinic, provision of a gout leaflet, a higher number of outpatient visits and non-smoking status. CONCLUSIONS Many patients with crystal-proven gout did not receive ULT as recommended. Even if ULT was initiated, the p-urate level was monitored infrequently and the dose of ULT was not escalated when necessary. The best outcomes were associated with continued care in a rheumatology clinic. FUNDING none. TRIAL REGISTRATION The study was assessed by the Ethics Committee, which decided it was a quality assurance project and the study was subsequently approved by the Regions data protection office service with ID 2018-62.

Body Fat Percentage, Waist Circumference, and Obesity As Risk Factors for Rheumatoid Arthritis: A Danish Cohort Study.

OBJECTIVE: To investigate the relationship between bioimpedance-derived total body fat percentage, waist circumference, and body mass index (BMI) and the subsequent development of rheumatoid arthritis (RA). METHODS: A population-based prospective cohort study was conducted using 55,037 patients enrolled in the Danish Diet, Cancer, and Health cohort. Baseline data included anthropometric measures and lifestyle factors. Individuals who developed RA were identified through linkage with the Danish National Patient Registry. The relationships between bioimpedance-derived body fat percentage, waist circumference, and BMI and incident RA were assessed using Cox proportional hazards regression models, stratifying by sex. All analyses were performed for overall RA and the serologic subtypes seropositive and other RA. RESULTS: A total of 210 men (37.6% with seropositive RA) and 456 women (41.0% with seropositive RA) developed RA during a median follow-up of 20.1 years. In women, the overall RA risk was 10% higher for each 5% increment of total body fat (hazard ratio [HR] 1.10 [95% confidence interval (95% CI) 1.02-1.18]), 5% higher for each 5-cm increment of waist circumference (HR 1.05 [95% CI 1.01-1.10]), and nearly 50% higher in those whose BMI was in the obese range compared to normal range BMI (HR 1.46 [95% CI 1.12-1.90]). These positive associations were also found for patients with other RA. In men, there were no clear associations between body fat percentage, waist circumference, or BMI and RA. No significant associations were found for seropositive RA in women or men, possibly related to low sample size. CONCLUSION: In women, higher body fat percentage, higher waist circumference, and obesity were associated with a higher risk of RA.

To switch or not to switch: results of a nationwide guideline of mandatory switching from originator to biosimilar etanercept. One-year treatment outcomes in 2061 patients with inflammatory arthritis from the DANBIO registry.

OBJECTIVES: Real-world evidence on effectiveness of switching to biosimila r etanercept is scarce. In Denmark, a nationwide guideline of mandatory switch from 50 mg originator (ETA) to biosimilar (SB4) etanercept was issued for patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA) and axial spondyloarthritis (AxSpA) in 2016. Clinical characteristics and treatment outcomes were studied in ETA-treated patients, who switched to SB4 (switchers) or maintained ETA (non-switchers). Retention rates were compared with that of a historic cohort of ETA-treated patients. Switchers who resumed ETA treatment (back-switchers) were characterised. METHODS: Observational cohort study based on the DANBIO registry. Treatment retention was explored by Kaplan-Meier plots and Cox regression (crude, adjusted). RESULTS: 1621 (79%) of 2061 ETA-treated patients switched to SB4. Disease activity was unchanged 3 months' preswitch/postswitch. Non-switchers often received 25 mg ETA (ETA 25 mg pens/syringes and powder solution were still available). One-year adjusted retention rates were: non-switchers: 77% (95% CI: 72% to 82%)/switchers: 83% (79% to 87%)/historic cohort: 90% (88% to 92%). Patients not in remission had lower retention rates than patients in remission, both in switchers (crude HR 1.7 (1.3 to 2.2)) and non-switchers (2.4 (1.7 to 3.6)). During follow-up, 120 patients (7% of switchers) back-switched to ETA. Back-switchers' clinical characteristics were similar to switchers, and reasons for SB4 withdrawal were mainly subjective. CONCLUSION: Seventy-nine per cent of patients switched from ETA to SB4. After 1 year, adjusted treatment retention rates were lower in switchers versus the historic ETA cohort, but higher than in non-switchers. Withdrawal was more common in patients not in remission. The results suggest that switch outcomes in routine care are affected by patient-related factors and non-specific drug effects.

Positive predictive value of first-time rheumatoid arthritis diagnoses and their serological subtypes in the Danish National Patient Registry.

PURPOSES: To assess whether the positive predictive value (PPV) of first-time rheumatoid arthritis (RA) diagnosis registration in the Danish National Patient Registry increases when data are linked to the RA treatment codes and to assess the PPV of first-time RA diagnoses according to RA serological subtypes. METHODS: Participants from the Danish Diet, Cancer, and Health cohort with at least one RA diagnosis, registered at one of the Central Denmark Region hospitals in the Danish National Patient Registry during the period 1977-2016, were identified. Register-based RA diagnoses were verified by scrutinizing medical records against RA classification criteria or clinical case RA. PPVs for overall RA, seropositive RA, and other RA were calculated for two models: first-time RA diagnosis registration ever in the Danish National Patient Registry and first-time RA diagnosis registration ever where subsequently a prescription had been redeemed for a synthetic disease-modifying antirheumatic drug. RESULTS: Overall, 205 of 311 first-time register-based RA diagnoses were verified (PPV: 61.9%; 95% CI: 56.9-67.0). Regarding RA serological subtypes, 93 of 150 register-based seropositive RA (PPV: 62.0; 95% CI: 53.9-69.5) and 36 of 144 other RA (PPV: 25.0; 95% CI: 18.5-32.8) were confirmed. When register-based RA diagnosis codes were linked to RA treatment codes, the PPVs increased substantially: the PPV for overall RA was 87.7% (95% CI: 82.5-91.5), the PPV for seropositive RA was 80.2% (95% CI: 71.6-86.7), and the PPV for other RA was 41.1% (95% CI: 30.2-52.9). CONCLUSION: The first-time RA diagnoses in the Danish National Patient Registry should be used with caution in epidemiology research. However, linking registry-based RA diagnoses to the subsequent RA treatment codes increases the probability of identifying true RA diagnoses, especially overall RA and seropositive RA.

A nationwide non-medical switch from originator infliximab to biosimilar CT-P13 in 802 patients with inflammatory arthritis: 1-year clinical outcomes from the DANBIO registry.

OBJECTIVES: According to guidelines, a nationwide non-medical switch from originator (INX, Remicade) to biosimilar infliximab (Remsima, CT-P13) was conducted in Danish patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA) and axial spondyloarthritis (AxSpA). We investigated disease activity before/after switching and retention rates in the DANBIO registry. METHODS: Disease activities 3 months before and after switch and changes over time were calculated. Flare was defined as change in 28 Joint Disease Activity Score (∆DAS28) ≥1.2 (RA/PsA) or Ankylosing Spondylitis Disease Activity Score (∆ASDAS) ≥1.3 (AxSpA). Crude and adjusted retention rates were compared with a historic cohort of INX-treated patients. RESULTS: Eight hundred and two patients switched (403 RA/120 PsA/279 AxSpA; 51% women, age (median (IQR): 55 (44-66)) years). Follow-up was 413 (339-442) days. Prior INX treatment duration was 6.8 (4.3-9.5) years. Disease activities were similar 3 months before/after switch. Crude 1-year CT-P13 retention rate (84.1 (95% CI 81.3 to 86.5)) was similar to the historic IFX cohort (86.2 (95% CI 84.0 to 88.0), p=0.22). The adjusted absolute retention rates were 83.4 (95% CI 80.8 to 86.2) and 86.8% (95% CI 84.8 to 88.8), respectively (p=0.03). In total 132 patients withdrew (lack of effect: 71/132=54%, adverse events: 37/132=28%). Patients with previous INX treatment duration >5 years had longer CT-P13 retention. CONCLUSION: In 802 arthritis patients treated with INX for median >6 years, a nationwide non-medical switch to CT-P13 had no negative impact on disease activity. Adjusted 1-year CT-P13 retention rate was slightly lower than for INX in a historic cohort.

[No evidence that diet has any influence on the aetiology of rheumatoid arthritis]. / Ingen evidens for at kosten har betydning for udvikling af reumatoid artritis

Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory disease affecting 0,5-1% of the population. Several genetic and environmental factors are implicated in the aetiology of RA. The only well-established environmental risk factor is tobacco smoking. In this review we examine data linking intake of fatty acids, meat, antioxidants and vitamin D with the risk of RA. Although there is some tendency to show a protective effect of fatty acids from fish on RA, generally, evidence on dietary risk factors is scarce with a lack of statistical significance and reproducibility.

A treat-to-target strategy with methotrexate and intra-articular triamcinolone with or without adalimumab effectively reduces MRI synovitis, osteitis and tenosynovitis and halts structural damage progression in early rheumatoid arthritis: results from the OPERA randomised controlled trial.

OBJECTIVES: To investigate whether a treat-to-target strategy with methotrexate and intra-articular glucocorticosteroid injections suppresses MRI inflammation and halts structural damage progression in patients with early rheumatoid arthritis (ERA), and whether adalimumab provides an additional effect. METHODS: In a double-blind, placebo-controlled trial, 85 disease-modifying antirheumatic drug-naïve patients with ERA were randomised to receive methotrexate, intra-articular glucocorticosteroid injections and placebo/adalimumab (43/42). Contrast-enhanced MRI of the right hand was performed at months 0, 6 and 12. Synovitis, osteitis, tenosynovitis, MRI bone erosion and joint space narrowing (JSN) were scored with validated methods. Dynamic contrast-enhanced MRI (DCE-MRI) was carried out in 14 patients. RESULTS: Synovitis, osteitis and tenosynovitis scores decreased highly significantly (p<0.0001) during the 12-months' follow-up, with mean change scores of -3.7 (median -3.0), -2.2 (-1) and -5.3 (-4.0), respectively. No overall change in MRI bone erosion and JSN scores was seen, with change scores of 0.1 (0) and 0.2 (0). The tenosynovitis score at month 6 was significantly lower in the adalimumab group, 1.3 (0), than in the placebo group, 3.9 (2), Mann-Whitney: p<0.035. Furthermore, the osteitis score decreased significantly during the 12-months' follow-up in the adalimumab group, but not in the placebo group, Wilcoxon: p=0.001-0.002 and p=0.062-0.146. DCE-MRI parameters correlated closely with conventional MRI inflammatory parameters. Clinical measures decreased highly significantly during follow-up. CONCLUSIONS: A treat-to-target strategy with methotrexate and intra-articular glucocorticosteroid in patients with ERA effectively decreased synovitis, osteitis and tenosynovitis and halted structural damage progression as judged by MRI. The findings suggest that addition of adalimumab is associated with further suppression of osteitis and tenosynovitis.

Adalimumab added to a treat-to-target strategy with methotrexate and intra-articular triamcinolone in early rheumatoid arthritis increased remission rates, function and quality of life. The OPERA Study: an investigator-initiated, randomised, double-blind, parallel-group, placebo-controlled trial.

OBJECTIVES: An investigator-initiated, double-blinded, placebo-controlled, treat-to-target protocol (Clinical Trials:NCT00660647) studied whether adalimumab added to methotrexate and intra-articular triamcinolone as first-line treatment in early rheumatoid arthritis (ERA) increased the frequency of low disease activity (DAS28CRP<3.2) at 12 months. METHODS: In 14 Danish hospital-based clinics, 180 disease-modifying anti-rheumatic drugs (DMARD)-naïve ERA patients (<6 months duration) received methotrexate 7.5 mg/week (increased to 20 mg/week within 2 months) plus adalimumab 40 mg every other week (adalimumab-group, n=89) or methotrexate+placebo-adalimumab (placebo-group, n=91). At all visits, triamcinolone was injected into swollen joints (max. four joints/visit). If low disease activity was not achieved, sulfasalazine 2 g/day and hydroxychloroquine 200 mg/day were added after 3 months, and open-label biologics after 6-9 months. Efficacy was assessed primarily on the proportion of patients who reached treatment target (DAS28CRP<3.2). Secondary endpoints included DAS28CRP, remission, Health Assessment Questionnaire (HAQ), EQ-5D and SF-12. Analysis was by intention-to-treat with last observation carried forward. RESULTS: Baseline characteristics were similar between groups. In the adalimumab group/placebo group the 12-month cumulative triamcinolone doses were 5.4/7.0 ml (p=0.08). Triple therapy was applied in 18/27 patients (p=0.17). At 12 months, DAS28CRP<3.2 was reached in 80%/76% (p=0.65) and DAS28CRP was 2.0 (1.7-5.2) (medians (5th/95th percentile ranges)), versus 2.6 (1.7-4.7) (p=0.009). Remission rates were: DAS28CRP<2.6: 74%/49%, Clinical Disease Activity Index≤2.8: 61%/41%, Simplified Disease Activity Index<3.3: 57%/37%, European League Against Rheumatism/American College of Rheumatology Boolean: 48%/30% (0.0008