Knut Mikkelsen

The comparative one‐year performance of anti–tumor necrosis factor α drugs in patients with rheumatoid arthritis, psoriatic arthritis, and ankylosing spondylitis: Results from a longitudinal, observational, multicenter study

OBJECTIVE To compare the 1-year retention rates of anti-tumor necrosis factor alpha (anti-TNFalpha) medications in patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA), and ankylosing spondylitis (AS) with complementary analyses of the effect on health status. METHODS Our analyses comprised 847, 172, and 249 anti-TNFalpha treatment courses in patients with RA, PsA, and AS, respectively. Crude drug survival was compared and hazard ratios (HRs) for treatment termination were calculated with adjustments for age, sex, investigators global assessment, and concomitant methotrexate (MTX). Adjusted changes in health-related quality of life (HRQOL) were compared among the groups. RESULTS Unadjusted 1-year retention rates were 65.4%, 77.3%, and 77.5% in the RA, PsA, and AS groups, respectively. The adjusted HRs for treatment termination were 0.76 (95% confidence interval [95% CI] 0.53-1.07) for PsA versus RA and 0.66 (95% CI 0.47-0.92) for AS versus RA. High baseline disease activity and female sex were significantly associated with premature treatment termination, whereas concomitant MTX was associated with better drug survival. However, the impact of MTX was apparent for RA and PsA, but not for AS in stratified analyses. The improvements in HRQOL were superior in patients with PsA and AS compared with RA. CONCLUSION Our results suggest that survival of anti-TNFalpha treatment is superior in AS and PsA patients compared with RA patients. Larger improvements in HRQOL in patients with spondylarthritides may contribute to the differences in drug survival. Concomitant MTX was associated with better retention rates in RA and PsA patients, but not AS patients.

The role of methotrexate co-medication in TNF-inhibitor treatment in patients with psoriatic arthritis: results from 440 patients included in the NOR-DMARD study

Background The role of co-medication with tumour necrosis factor inhibitors (TNFi) is well established in rheumatoid arthritis and ankylosing spondylitis. In psoriatic arthritis (PsA) there is little evidence available on this issue. Material and methods The analyses were based on data from the Norwegian longitudinal observational study on disease-modifying antirheumatic drugs (NOR-DMARD). Patients with PsA starting their first TNFi, either as monotherapy or with concomitant methotrexate (MTX), were selected. Baseline characteristics, responses after 3, 6 and 12 months, and drug survival were compared between those with and without MTX co-medication. A secondary analysis was performed on patients who had confirmed swollen joints at baseline. Cox regression was used to identify predictors of discontinuation. Results We included 440 patients, 170 receiving TNFi as monotherapy and 270 receiving concomitant MTX. The groups had similar baseline characteristics, except for number of swollen joints, which was higher in the concomitant MTX group. Responses were similar in the two groups in both analyses. Drug survival analyses revealed a borderline significant difference in favour of patients receiving co-medication (p=0.07), and this was most prominent for patients receiving infliximab (IFX) (p=0.01). In the Cox regression analysis lack of concomitant MTX and current smoking were independent predictors of discontinuation of TNFi. Conclusions We found similar responses to TNFi in patients with and without concomitant MTX, but drug survival was superior in patients receiving co-medication. The effect of MTX on drug survival was most prominent in patients receiving IFX. Smoking at baseline and use of TNFi as monotherapy were identified as independent predictors of drug discontinuation.

Effectiveness of switching between TNF inhibitors in ankylosing spondylitis: data from the NOR-DMARD register

Objective To assess the effectiveness of switching to a second tumour necrosis factor inhibitor (TNFi) in patients with ankylosing spondylitis (AS). Methods Data were extracted from an ongoing longitudinal observational multicentre study in Norway. This study included anti-TNF naïve patients with AS starting treatment with a TNFi as well as treatment with a second TNFi in these same patients. Effectiveness data and 2-year drug survival were compared between switchers and non-switchers and within switchers (first and second TNFi). Results 514 anti-TNF naïve patients with AS were included; 77 patients switched to a second TNFi while 437 patients did not switch. The percentages of non-switchers using etanercept, infliximab or adalimumab were 53%, 32% and 15%, and the percentages of first and second TNFi in the switchers were 42%, 53% and 5% and 40%, 23% and 36%, respectively. The reason for switching was insufficient response (IR) in 30, adverse events (AEs) in 44 and not reported in 3 patients. Baseline disease activity was similar between the groups. Three-month BASDAI 50 and ASAS 40 responses were achieved by 49% and 38% of non-switchers, by 25% and 30% of switchers after the first TNFi and by 28% and 31% after the second TNFi. The 3-month disease activity level was higher for switchers on the second TNFi than for non-switchers. Drug withdrawal rate was higher during the second TNFi among switchers than for non-switchers (p=0.001). No difference was found in the effectiveness of the second TNFi between switchers due to IR and AE. Conclusion This study confirms that switching to a second TNFi can be effective in AS and can be as useful as in rheumatoid arthritis, although overall effectiveness seems to be somewhat lower than in non-switchers.

Effectiveness and retention rates of methotrexate in psoriatic arthritis in comparison with methotrexate-treated patients with rheumatoid arthritis

Objective To examine the effectiveness and 2-year retention rates of methotrexate (MTX) in MTX naïve patients with psoriatic arthritis (PsA). Methods Data on 430 patients with PsA participating in an ongoing longitudinal observational multicentre study in Norway were analysed. 1218 MTX naïve patients with rheumatoid arthritis (RA) from the same study served as a reference population. Assessments included measures of disease activity (28 joint counts, acute phase reactants), health status and utility scores. Six-month effectiveness data were compared both by crude analyses and with adjustments for age, sex and the respective baseline values. Two-year drug survival was compared by Kaplan–Meier and Cox regression analyses. Results After 6 months of MTX treatment, both patients with PsA and those with RA improved in most disease activity measures and patient reported outcomes. In the adjusted analysis, patients with PsA tended to have less improvement, but changes were in the same range as in patients with RA. Two-year retention rates of MTX therapy in patients with PsA and RA were 65% and 66%, respectively, with only minor differences in reported reasons for discontinuation. Lower age, longer disease duration and higher Modified Health Assessment Questionnaire (MHAQ) score and patient global assessment were independent predictors of MTX termination within the first 2 years of treatment. Conclusion In this real-life study, MTX treatment was associated with improvement in disease activity and health-related quality of life in patients with PsA after 6 months of treatment. Retention rates of MTX were similar in PsA and RA.

Switching between TNF inhibitors in psoriatic arthritis: data from the NOR-DMARD study

Background Tumour necrosis factor inhibitors (TNFi) are efficacious in patients with psoriatic arthritis (PsA), but some patients do not respond or do not tolerate their first TNFi, and are switched to a different TNFi. Evidence supporting this practice is limited, and we wanted to investigate the effectiveness of switching to a second TNFi. Material and methods From a longitudinal observational study (LOS) we selected patients with PsA who were starting their first TNFi, and identified patients who had switched to a second TNFi (‘switchers’). Three-month responses and 3-year drug-survival were compared between switchers and non-switchers, and within switchers. Results Switchers (n=95) receiving their second TNFi had significantly poorer responses compared with non-switchers (n=344) (ACR50 response: 22.5% vs 40.0%, DAS28 remission: 28.2% vs 54.1%). There was a trend towards poorer responses to the second TNFi compared with the first TNFi within switchers. Estimated 3-year drug-survival was 36% for the second TNFi compared with 57% for the first TNFi overall. Conclusions 20–40% of patients had a response on a second TNFi after having failed one TNFi in this LOS. This observation highlights the need for treatments with other mechanisms of action than TNF inhibition in patients with PsA.

The comparative effectiveness of anti-TNF therapy and methotrexate in patients with psoriatic arthritis: 6 month results from a longitudinal, observational, multicentre study

Objectives: To compare the response to treatment with tumour necrosis factor (TNF) inhibitors and methotrexate (MTX) monotherapy in patients with psoriatic arthritis (PsA) within a real-life clinical setting. Methods: We analysed data from an ongoing longitudinal, observational multicentre study in Norway. Our data comprised 526 cases of patients with PsA who received either anti-TNF treatment (n = 146) or MTX monotherapy (n = 380) and were followed for at least 6 months with measures of disease activity, health status and utility scores. A propensity score was computed to adjust for channelling bias. The changes in measures of disease activity and health-related quality of life from baseline to 3- and 6-month follow-up were compared between the groups with adjustments for the baseline value of the dependent variable and the propensity score (analyses of covariance (ANCOVA)). Results: The groups were significantly different at baseline with respect to demographic and disease activity measures. The variables included in the propensity score were age, sex, number of previous disease modifying anti-rheumatic drugs (DMARDs), presence of erosive disease, treatment centre and investigator’s global assessment. The adjusted changes at 6 months were significantly larger in the anti-TNF group for ESR, DAS-28, M-HAQ, patient’s assessments of pain, fatigue and global disease activity on a visual analogue scale (VAS) and 4 out of 8 SF-36 dimensions. Conclusions: Clinical improvement was superior with TNF inhibitors compared to MTX monotherapy in patients with PsA, when assessed in this setting of daily clinical practice.

Work disability and health-related quality of life in males and females with psoriatic arthritis

Objectives: To compare health status, demographic variables and work disability (WD) between males and females with psoriatic arthritis (PsA) in the 18–45 age group, and further to compare health status between those with and without WD for each gender and to identify variables associated with WD. Methods: A cross-sectional study was carried out of patients with PsA with peripheral arthritis at the time at which they started disease-modifying antirheumatic drug therapy (DMARD) and/or biological treatment. Patients receiving a permanent national WD pension corresponding to ⩾50% were defined as work disabled. Gender differences were examined with regard to health status, demographic variables and WD. Mann–Whitney U test and Pearson χ2 were applied for group comparisons between males and females and work disabled versus not work disabled for each gender. Multiple logistic regression analyses with adjustments for duration of education, disease duration, age, erosive disease, disability score (Modified Health Assessment Questionnaire; MHAQ), the short form-36 (SF-36) mental health score, and gender were used to identify variables associated with WD. Results: Out of 271 (102 females) patients, the number (%) of work-disabled females/males was 33 (32.7%)/29 (17.4%) (p = 0.004). Work-disabled patients had generally worse health status than non-work-disabled patients, and these differences were generally more pronounced in males than in females. In the multiple logistic regression model, low educational level, increasing disability score (MHAQ), presence of erosive disease, female gender and disease duration were independently associated with WD. Conclusions: WD in patients with PsA below 45 years of age was independently associated with educational level, disability score, erosive disease, female gender and disease duration.

Pregnancy and delivery in women with chronic inflammatory arthritides with a specific focus on first birth.

OBJECTIVE To examine possible associations between chronic inflammatory arthritides and pregnancy outcomes with separate analyses of first and subsequent births before and after diagnosis. METHODS Linkage of data from a registry of patients with chronic inflammatory arthritides and the Medical Birth Registry of Norway enabled a comparison of pregnancy outcomes in women with chronic inflammatory arthritides and pregnancy outcomes in reference subjects. Outcomes of first birth and subsequent births before and after diagnosis were analyzed separately. Associations between chronic inflammatory arthritides and the womens health during pregnancy and delivery as well as perinatal outcomes were assessed in logistic regression analyses with adjustments for maternal age at delivery and gestational age. RESULTS We analyzed 128 first births and 151 subsequent births after diagnosis and 286 first births and 262 subsequent births before diagnosis in patients and compared them with first and subsequent births in reference subjects. Firstborn children of women diagnosed as having chronic inflammatory arthritides were more often preterm (odds ratio [OR] 1.85 [95% confidence interval (95% CI) 1.09-3.13]) and small for gestational age (OR 1.60 [95% CI 1.00-2.56]). They also had lower mean birth weight (P=0.01) and higher perinatal mortality (OR 3.26 [95% CI 1.04-10.24]). Birth by caesarean section (all classifications) was more frequent in patients than in reference subjects, and elective caesarean section was 2-fold more frequent in patients, both in first birth (OR 2.60 [95% CI 1.43-4.75]) and in subsequent births (OR 2.18 [95% CI 1.33-3.58]). No excess risks of clinical importance were observed prior to diagnosis of chronic inflammatory arthritides. CONCLUSION Excess risks were related to first birth in women diagnosed as having chronic inflammatory arthritides, including a higher rate of perinatal mortality. A higher caesarean section rate was related to all patient deliveries. Mainly, pregnancy outcomes before diagnosis did not differ from those in reference subjects.

Time trends in disease activity, response and remission rates in rheumatoid arthritis during the past decade: results from the NOR-DMARD study 2000–2010

Objectives To investigate whether baseline disease activity levels and responses in patients with rheumatoid arthritis (RA) changed during the period 2000–2010. Methods Data were provided by the Norwegian disease-modifying antirheumatic drug (NOR-DMARD) study. Patients with inflammatory joint diseases starting new treatment with disease-modifying antirheumatic drugs (DMARDs) were consecutively included and followed longitudinally. Time trend analyses were performed in methotrexate (MTX)-naïve RA patients starting MTX monotherapy (MTX mono) and biologic DMARD (bDMARD)-naïve RA patients starting tumour necrosis factor inhibitors+MTX (TNFi+MTX). Results A total of 2573 patients were included in the analyses: MTX mono n=1866 (69.9% female, 62.0% RF+, mean (SD) age 56.0 (13.7) years, median (25–75 percentile) time from diagnosis 0.2 (0.01–2.8) years); TNFi+MTX n=707 (70.3% female, 75.0% RF+, mean (SD) age 52.1 (13.2) years, median (25–75 percentile) time from diagnosis 5.7 (2.0–13.7) years). Significant time trends towards lower baseline disease activity score 28 (DAS28) as well as other disease activity measures were found in both groups (DAS28 from 5.17 to 4.75 in MTX mono and from 5.88 to 4.64 in TNFi+MTX), and disease duration became shorter. Six-month DAS28 remission rates increased significantly over the years (from 17.8 to 37.6 in MTX mono and from 16.9 to 46.3 in TNFi+MTX). Conclusions During the last decade, baseline RA disease activity level at the time of starting MTX as well as TNFi+MTX decreased from high to moderate. A more than twofold increase in 6-month remission rates was observed in both groups. Our findings indicate that clinicians have implemented modern, more aggressive treatment strategies, which hopefully will lead to better long-term disease outcomes.

Increased levels of serum pentraxin 3, a novel cardiovascular biomarker, in patients with inflammatory rheumatic disease.

Pentraxin 3 (PTX3), a key component of innate immunity, is a strong marker of disease severity in coronary artery disease (CAD). The aim of this study was to compare levels of serum PTX3 in CAD patients with and without inflammatory rheumatic disease (IRD) and in healthy controls.