Cecilie Kaufmann

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.

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.

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.

Fertility in women with chronic inflammatory arthritides

OBJECTIVE To compare fertility rates in women with RA, other chronic arthritides (OCAs) and JIA with reference women from the general population. METHODS Each woman from a Norwegian patient registry was matched by year of birth with 100 reference women randomly selected from the National Population Registry. Data linkage of patients and references with the Medical Birth Registry of Norway (MBRN) identified all offspring in patients and references until October 2007, and indirectly also nulliparous (childless) women. Groups were compared with Mann-Whitney U-test for continuous variables and chi-squared tests for categorical variables. Poisson regression analysis was applied to calculate relative fertility rates in the diagnostic groups vs references. RESULTS Among 631 patients 849 children were registered in MBRN. Of these, 289 children (34.0%) were born after time of diagnosis vs 44.3% in references. Altogether, 206 of 631 patients (32.6%) were nulliparous vs 26.4% in references (P < 0.001). Among RA patients, 28.4% (96 of 338) were nulliparous vs 24.5% in references (P = 0.09), 30.7% (67 of 218) in OCA patients vs 24.5% in references (P = 0.03) and 57.3% (43 of 75) in JIA patients vs 40.9% in references (P = 0.004). Adjusted relative fertility rates in RA, OCA and JIA after diagnosis were 0.88, 0.84 and 0.84, respectively, compared with references. CONCLUSION A higher proportion of women with chronic inflammatory arthritides were nulliparous compared with references, and relative fertility rates were reduced in all patient groups.

Postpartum onset of rheumatoid arthritis and other chronic arthritides: results from a patient register linked to a medical birth registry

Background: It is known that onset of rheumatoid arthritis (RA) is increased post partum. Objective: To compare incidence rates between RA and other chronic arthritides (OCA) 0–24 months after delivery, and to compare the incidence rates within each group 0–24 versus 25–48 months post partum. Methods: Premenopausal women from a Norwegian patient register were linked with the Medical Birth Registry of Norway to study the interval between delivery and time of diagnosis. Cox regression analysis with adjustments for age at delivery and birth order was applied to compare proportions of incident cases of RA and OCA with onset 0–24 months post partum. Poisson regression analysis with adjustment for the population at risk was applied to estimate the incidence rate ratio (IRR) 0–24 versus 25–48 months post partum. Results: Of 183 RA and 110 patients with OCA diagnosed after delivery, 69 (37.7%) had RA and 31 (28.2%) OCA during the first 24 months post partum (p = 0.09). The IRR (95% CI) for diagnosis during 0–24 months versus 25–48 months was 1.73 (1.11 to 2.70) (p = 0.01) for RA, 1.05 (0.59 to 1.84) (p = 0.86) for OCA. The IRR was 2.23 (1.06 to 4.70) and 1.87 (0.67 to 5.21), respectively, when only considering diagnoses after the first pregnancy. Clinical characteristics were similar within each diagnostic group. Conclusion: The proportions of incident cases with onset 0–24 months after delivery were not different between RA and OCA. A peak in incidence during 0–24 months was seen in the RA group, both when considering all pregnancies and only the first pregnancy.

Comparison of work disability and health‐related quality of life between males and females with rheumatoid arthritis below the age of 45 years

Objectives: To compare work disability (WD) and health status between males and females with rheumatoid arthritis (RA) in the age group 18–45 years, and to compare health status between patients with and without WD within each gender, and finally to identify factors independently associated with WD in this age group. Methods: A cross‐sectional study of RA patients at the time starting with disease‐modifying antirheumatic drug (DMARD) therapy and/or biological treatment. Patients receiving a permanent, national WD pension corresponding to ⩾ 50% were defined as work disabled. We examined gender differences with regard to disease characteristics, health status and WD. The Mann–Whitney U‐test and Pearson’s χ2‐test were applied for group comparisons. Multiple logistic regression analyses with adjustments for duration of education, disease duration, age, erosive disease, disability score [using the Modified Health Assessment Questionnaire (MHAQ)], Disease Activity Score‐28 (DAS‐28), the Short Form Health Survey (SF‐36) mental health score and gender were used to identify variables associated with WD. Results: Out of 474 (372 females) patients, the number (%) of work‐disabled females/males was 91 (24.7)/8 (8.1) (p<0.001). WD was associated with worse health status in both genders. The odds ratio (95% confidence interval) [OR (95% CI)] for WD in females vs. males was 4.84 (1.85–12.65) in the multivariate analyses. Other factors independently associated with WD were worse mental health, disease duration and low level of education. Conclusion: Females with RA had a fourfold increased risk of WD compared to men. Low level of education, disease duration and worse mental health were also independently associated with WD.

Adalimumab and methotrexate is more effective than adalimumab alone in patients with established rheumatoid arthritis: results from a 6-month longitudinal, observational, multicentre study

Objectives: To compare the effectiveness of adalimumab monotherapy and adalimumab and methotrexate (MTX) combination therapy in patients with established rheumatoid arthritis. Methods: Data from an ongoing longitudinal observational study in Norway were used to compare response to treatment with two different adalimumab regimens (monotherapy, n = 84; combination with MTX, n = 99). Patients were assessed with measures of disease activity, health status and utility scores. Within-group changes were analysed from baseline to follow-up at 3 and 6 months and the changes were compared between groups after adjustment for the propensity score. The groups were also compared for the proportions of patients achieving European League Against Rheumatism (EULAR) good response, Disease Activity Score (DAS)28 remission and treatment terminations. Results: The improvement from baseline was significant for all measures in the adalimumab and MTX group, but only for DAS28, joint counts, two Short-form Health Survey with 36 questions (SF-36) dimensions and patient’s and investigator’s global assessment in the monotherapy group. All between-group differences were numerically in favour of combination therapy and significant for C reactive protein, joint counts, DAS28, Modified Health Assessment Questionnaire, investigator’s global assessment, four SF-36 dimensions and Short Form 6D at 6 months. More patients in the combination therapy group reached EULAR good response (p<0.001) and remission (p = 0.07). At 6 months, 80.8% of the patients in the combination therapy group and 59.5% in the monotherapy group remained on treatment (p = 0.002). More withdrawals in the monotherapy group were due to adverse events. Conclusions: Our results were consistent across several categories of end points and suggest that adalimumab combined with MTX is effective in patients with rheumatoid arthritis treated in daily clinical practice and is superior to adalimumab monotherapy.