Pil Højgaard

Association between tobacco smoking and response to tumour necrosis factor α inhibitor treatment in psoriatic arthritis: results from the DANBIO registry

Objectives To investigate the association between tobacco smoking and disease activity, treatment adherence and treatment responses among patients with psoriatic arthritis (PsA) initiating the first tumour necrosis factor α inhibitor therapy (TNFi) in routine care. Methods Observational cohort study based on the Danish nationwide DANBIO registry. Kaplan–Meier plots, logistic and Cox regression analyses by smoking status (current/previous/never smoker) were calculated for treatment adherence, ACR20/50/70-responses and EULAR-good-response. Additional stratified analyses were performed according to gender and TNFi-subtype (adalimumab/etanercept/infliximab). Results Among 1388 PsA patients included in the study, 1148 (83%) had known smoking status (33% current, 41% never and 26% previous smokers). Median follow-up time was 1.22 years (IQR 0.44–2.96). At baseline, current smokers had lower Body Mass Index (27 kg/m2 (23–30)/28 kg/m2 (24–31)) (median (IQR)), shorter disease duration (3 years (1–8)/5 years (2–10)), lower swollen joint count (2 (0–5)/3 (1–6)), higher visual-analogue-scale (VAS) patient global (72 mm (54–87)/68 mm (50–80)), VAS fatigue (72 mm (51–86)/63 mm (40–77)) and Health Assessment Questionnaire (HAQ) score (1.1 (0.7 to 1.5)/1.0 (0.5 to 1.5)) than never smokers (all p<0.05). Current smokers had shorter treatment adherence than never smokers (1.56 years (0.97 to 2.15)/2.43 years (1.88 to 2.97), (median (95% CI)), log rank p=0.02) and poorer 6 months’ EULAR-good-response rates (23%/34%), ACR20 (24%/33%) and ACR50 response rates (17%/24%) (all p<0.05), most pronounced in men. In current smokers, the treatment adherence was poorer for infliximab (HR) 1.62, 95% CI 1.06 to 2.48) and etanercept (HR 1.74, 1.14 to 2.66) compared to never smokers, but not for adalimumab (HR 0.80, 0.52 to 1.23). Conclusion In PsA, smokers had worse baseline patient-reported outcomes, shorter treatment adherence and poorer response to TNFis compared to non-smokers. This was most pronounced in men and in patients treated with infliximab or etanercept.

Predictors of revision, prosthetic joint infection and mortality following total hip or total knee arthroplasty in patients with rheumatoid arthritis: a nationwide cohort study using Danish healthcare registers

Objectives To investigate predictors of 10-year risk of revision and 1-year risk of prosthetic joint infection (PJI) and death following total hip/total knee arthroplasty (THA/TKA) in (1) patients with rheumatoid arthritis (RA) compared with patients with osteoarthritis (OA); and (2) patients with RA treated with biological disease-modifying antirheumatic drugs (bDMARD) within 90 days preceding surgery compared with non-treated. Methods Register-based cohort study using the Danish National Patient Register, the DANBIO rheumatology register (RA-specific confounders and treatment episodes) and the Danish Hip and Knee Arthroplasty Registers. Survival analyses were used to calculate confounder-adjusted sub-HRs (SHR) and HRs. Results In total, 3913 patients with RA with THA/TKA were compared with 120 499 patients with OA. Patients with RA had decreased risk of revision (SHR 0.71 (0.57–0.89)), but increased risk of PJI (SHR=1.46 (1.13–1.88)) and death (HR=1.25 (1.01–1.55)). In DANBIO, 345 of 1946 patients with RA with THA/TKA had received bDMARD treatment within 90 days preceding surgery. bDMARD-treated patients did not have a statistically significant increased risk of revision (SHR=1.49 (0.65–3.40)), PJI (SHR=1.61 (0.70–3.69)) nor death (HR=0.75 (0.24–2.33)) compared with non-treated. Glucocorticoid exposure (HR=2.87 (1.12–7.34)) and increasing DAS28 (HR=1.49 (1.01–2.20)) were risk factors for mortality. Conclusion Patients with RA had a decreased 10-year risk of revision while the risk of death and PJI was increased compared with patients with OA following THA/TKA. bDMARD exposure was not associated with statistically significant increased risk of neither PJI nor death in this study. Glucocorticoid exposure and increased disease activity were associated with an increased risk of death.

Antibodies to Infliximab and Adalimumab in Patients with Rheumatoid Arthritis in Clinical Remission: A Cross-Sectional Study

Objective. To investigate if antibodies towards biological TNF-α inhibitors (anti-TNFi Abs) are present in patients with rheumatoid arthritis (RA) in clinical remission and to relate any anti-TNFi Abs to circulating level of TNF-α inhibitor (TNFi). Methods. Patients with RA, treated with infliximab or adalimumab, and in clinical remission (DAS28(CRP) < 2.6) were included from 6 out-patient clinics. In blood samples, presence of anti-TNFi Abs was determined by radioimmunoassay, and concentration of bioactive TNFi was measured by a cell-based reporter gene assay. Results. Anti-TNFi Abs were present in 8/44 patients (18%) treated with infliximab and 1/49 patients (2%) treated with adalimumab (p = 0.012). In the former group, anti-TNFi Abs corresponded with low levels of TNFi (p = 0.048). Anti-TNFi Ab-positive patients had shorter disease duration at initiation of TNFi therapy (p = 0.023) but were similar for the rest of the compared parameters. Conclusions. In RA patients in clinical remission, anti-TNFi Abs occur frequently in patients treated with infliximab, while they occur rarely in patients treated with adalimumab. Presence of anti-infliximab Abs is accompanied by low or undetectable levels of infliximab. These data suggest that continued infliximab treatment may be redundant in a proportion of RA patients treated with infliximab and in clinical remission.

A systematic review of measurement properties of patient reported outcome measures in psoriatic arthritis: A GRAPPA-OMERACT initiative

BACKGROUND An updated psoriatic arthritis (PsA) core outcome set (COS) for randomized controlled trials (RCTs) was endorsed at the Outcome Measures in Rheumatology (OMERACT) meeting in 2016. OBJECTIVES To synthesize the evidence on measurement properties of patient reported outcome measures (PROMs) for PsA and thereby contribute to development of a PsA core outcome measurement set (COMS) as described by the OMERACT Filter 2.0. METHODS A systematic literature search was performed in EMBASE, MEDLINE and PsycINFO on Jan 1, 2017 to identify full-text articles with an aim of assessing the measurement properties of PROMs in PsA. Two independent reviewers rated the quality of studies using the COnsensus based standards for the Selection of health Measurement INstruments (COSMIN) checklist, and performed a qualitative evidence synthesis. RESULTS Fifty-five studies were included in the systematic review. Forty-four instruments and a total of 89 scales were analyzed. PROMs measuring COS domains with at least fair quality evidence for good validity and reliability (and no evidence for poor properties) included the Stockerau Activity Score for PsA (German), Psoriasis Symptom Inventory, visual analogue scale for Patient Global, 36 Item Short Form Health Survey Physical Function subscale, Health Assessment Questionnaire Disability Index, Bath Ankylosing Spondylitis Functional Index, PsA Impact of Disease questionnaire, PsA Quality of Life questionnaire, VITACORA-19, Functional Assessment of Chronic Illness Therapy Fatigue scale and Social Role Participation Questionnaire. CONCLUSIONS At least one PROM with some evidence for aspects of validity and reliability was available for six of the eight mandatory domains of the PsA COS.

Incidence of hip and knee replacement in patients with rheumatoid arthritis following the introduction of biological DMARDs: an interrupted time-series analysis using nationwide Danish healthcare registers

Objectives To study the impact of the introduction of biological disease-modifying anti-rheumatic drugs (bDMARDs) and associated rheumatoid arthritis (RA) management guidelines on the incidence of total hip (THR) and knee replacements (TKR) in Denmark. Methods Nationwide register-based cohort and interrupted time-series analysis. Patients with incident RA between 1996 and 2011 were identified in the Danish National Patient Register. Patients with RA were matched on age, sex and municipality with up to 10 general population comparators (GPCs). Standardised 5-year incidence rates of THR and TKR per 1000 person-years were calculated for patients with RA and GPCs in 6-month periods. Levels and trends in the pre-bDMARD (1996–2001) were compared with the bDMARD era (2003–2016) using segmented linear regression interrupted by a 1-year lag period (2002). Results We identified 30 404 patients with incident RA and 297 916 GPCs. In 1996, the incidence rate of THR and TKR was 8.72 and 5.87, respectively, among patients with RA, and 2.89 and 0.42 in GPCs. From 1996 to 2016, the incidence rate of THR decreased among patients with RA, but increased among GPCs. Among patients with RA, the incidence rate of TKR increased from 1996 to 2001, but started to decrease from 2003 and throughout the bDMARD era. The incidence of TKR increased among GPCs from 1996 to 2016. Conclusion We report that the incidence rate of THR and TKR was 3-fold and 14-fold higher, respectively among patients with RA compared with GPCs in 1996. In patients with RA, introduction of bDMARDs was associated with a decreasing incidence rate of TKR, whereas the incidence of THR had started to decrease before bDMARD introduction.

The impact of comorbidities on tumor necrosis factor inhibitor therapy in psoriatic arthritis: A population-based cohort study

The objective of this population‐based cohort study was to investigate the impact of comorbidities on disease activity, treatment response, and persistence with the first‐tried tumor necrosis factor inhibitor (TNFi) in patients with psoriatic arthritis (PsA).

Pain mechanisms and ultrasonic inflammatory activity as prognostic factors in patients with psoriatic arthritis: protocol for a prospective, exploratory cohort study.

Introduction Persistent pain is a major concern for patients with psoriatic arthritis (PsA). Pain may be due to inflammatory activity or augmented central pain processing. Unawareness of the origin and mechanisms of pain can lead to misinterpretation of disease activity (by composite scores) and erroneous treatments. Ultrasonography (US) is a highly sensitive method to detect tissue inflammation. Evaluating pain mechanisms in relation to US measures may prove valuable in predicting response to treatment in PsA. Aims To study the association and prognostic value of pain mechanisms, ultrasonic activity and clinical outcomes in patients with PsA who intensify antirheumatic treatment. Methods and analyses 100 participants >18 years of age with PsA who initiate or switch antirheumatic treatment (biologicals and/or conventional synthetic disease-modifying antirheumatic drugs (DMARDs)) will be prospectively recruited from outpatient clinics in Copenhagen. All data (demographics, clinical, imaging, blood samples and patient-reported outcomes) will be collected at baseline and after 4 months. Pain is assessed by the PainDETECT Questionnaire, Visual Analogue Scale for pain, Swollen to Tender Joint Count Ratio, Widespread Pain Index and tender point examination. The association between pain variables and clinical/US characteristics will be described by correlation analyses. The predictive value of pain measures and baseline US scores on treatment response will be analysed with regression models. Outcomes are composite and clinical, as well as patient reported. Ethics and dissemination The study is approved by the ethics committee of the Capital Region of Denmark (H-15009080) and has been designed in cooperation with patient research partners. The study is registered at clinicaltrials.gov (number NCT02572700). Results will be disseminated through publication in international peer-reviewed journals. Trial registration number NCT02572700, Pre-results.

Content and Face Validity and Feasibility of 5 Candidate Instruments for Psoriatic Arthritis Randomized Controlled Trials: The PsA OMERACT Core Set Workshop at the GRAPPA 2017 Annual Meeting.

The Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA)–Outcome Measures in Rheumatology (OMERACT) Psoriatic Arthritis (PsA) Core Set working group is in the process of selecting core instruments for PsA clinical trials. During a 2-h workshop and breakout group discussions at the GRAPPA 2017 annual meeting in Amsterdam, the Netherlands, participants discussed the first set of candidate instruments to be taken through the OMERACT Filter 2.1 instrument selection process: 66/68 swollen/tender joint count (66/68JC), Spondyloarthritis Consortium of Canada (SPARCC) enthesitis index, patient’s global assessment (GRAPPA and OMERACT formulations), Health Assessment Questionnaire–Disability Index (HAQ-DI), Psoriatic Arthritis Impact of Disease (PsAID) questionnaires 9 and 12, and Functional Assessment of Chronic Illness Therapy (FACIT) Fatigue. Based on the assessment of domain match (content and face validity) and feasibility according to the OMERACT instrument selection criteria, the working group recommends continuing with appraisal of construct validity and discrimination for 66/68JC, SPARCC, PsAID 9 and 12, HAQ-DI, and FACIT-Fatigue. In addition, it recommends repeating the OMERACT Filter 2.1 process for patient global instruments because of insufficient votes. Additional sets of candidate instruments for the PsA core instrument set will be evaluated in a similar process.

Gender differences in biologic treatment outcomes-a study of 1750 patients with psoriatic arthritis using Danish Health Care Registers

Objective We aimed to investigate gender differences in disease manifestations, patient-reported outcomes, comorbidities and treatment effectiveness among patients with PsA treated with their first TNFα inhibitor (TNFI). Methods In this observational cohort study, the DANBIO register provided prospectively collected data on PsA patients who initiated their first TNFI in 2000-15. Comorbidity information was achieved from the Danish Nationwide Patient Register. Response to treatment was assessed according to EULAR and ACR criteria at 3 and 6 months. Cox and logistic regression models analysed the impact of gender on TNFI persistence and response, respectively, while adjusting for a priori selected confounders including clinical-, laboratory- and patient-reported factors, comorbidities and lifestyle characteristics. Results A total of 1750 PsA patients (935 women) were included. At baseline, women were older (49 years/47 years), more often smokers (32%/26%), had worse patient-reported scores (e.g. global score 71 mm/65 mm) and higher frequencies of hospital-diagnosed anxiety or depression (7%/4%) and chronic pulmonary disease (7%/3%) than men (all P < 0.01). Median TNFI persistence was 3.8 years (95% CI: 3.0, 5.7) in men vs 1.4 (1.1, 1.8) in women (P < 0.001). Men had higher odds of achieving response after 3 and 6 months, for example, adjusted odds ratio = 3.2 (1.6, 6.1) for EULAR good/moderate response (vs women) at 6 months. Conclusion Male gender was strongly associated with greater TNFI treatment effectiveness. Adjustment for baseline risk factors including patient-reported outcomes, disease activity, comorbidities and lifestyle factors did not influence this relationship, which suggests a role of biological factors.

Pain mechanisms and ultrasonic inflammatory activity as prognostic factors in patients with psoriatic arthritis: A prospective cohort study

To study the prognostic value of widespread pain and of musculoskeletal ultrasound (US) examination for subsequent treatment outcomes in patients with psoriatic arthritis (PsA).