Elisabet Lindqvist

Treatment with TNF blockers and mortality risk in patients with rheumatoid arthritis

Objective: To assess mortality in patients with rheumatoid arthritis (RA) treated with tumour necrosis factor (TNF) inhibitors, compared with a standard RA population. Methods: Patients were recruited from a regional register, which includes over 90% of patients with RA treated with TNF blockers in the area in 1999 or later, and a local community-based cohort of patients with RA, established in 1997. Of a total of 1430 patients in the combined cohort <80 years old, 921 received treatment with TNF inhibitors during the study period. The total cohort was linked with the national register for cause of death. Overall mortality in those treated versus those not treated with TNF blockers was estimated using standardised mortality ratios and time-dependent Cox proportional hazards. Results: There were 188 deaths per 7077 person-years at risk in the total cohort. Controlling for age, sex, disability and baseline comorbidity, the adjusted HR for death was 0.65 (95% CI 0.46 to 0.93) in those treated with anti-TNF versus those not treated. The effect was significant in women (HR = 0.52, 95% CI 0.33 to 0.82) but not in men (HR = 0.95, 95% CI 0.52 to 1.71). Conclusion: After adjusting for disease severity, treatment with TNF inhibitors was found to be associated with a reduced mortality in women but not men with RA. These findings are compatible with a critical role for inflammation in RA-associated premature mortality.

Course of radiographic damage over 10 years in a cohort with early rheumatoid arthritis

Objective: To investigate development of radiographic damage in hands and feet of patients with early rheumatoid arthritis (RA) monitored prospectively for 10 years, and to search for prognostic factors. Patients and methods: 181 patients with early RA (mean disease duration one year) were assessed annually with radiographs of hands and feet during years 0–5 and at year 10. Radiographs were evaluated according to Larsen (range 0–200). Predictive factors for progressive disease for years 0–5 and 5–10 were evaluated by logistic regression analyses. Results: 82/168 (49%) patients had erosions at inclusion and almost all became erosive with time (90% after two years and 96% after 10 years). Radiographic progression was most rapid during the first two years and 75% of all damage occurred during the first five years. The median Larsen score increased from 6 at inclusion to 41 after five years and 54 after 10 years. Only 5.3% of all evaluated joints became maximally eroded, the second metacarpophalangeal joint being the most commonly affected. Mean ESR during the first three months and rheumatoid factor status were significant predictors for radiographic progressive disease, it was not possible to predict non-progressive disease. Conclusions: Joint damage in hands and feet developed early and progression was most rapid during the first years of disease. The different rates of progression at different stages should be considered in the design of trials of drugs aimed at retarding joint damage. Disease activity at study start influenced the degree of joint damage during the entire 10 years.

Ten year outcome in a cohort of patients with early rheumatoid arthritis: health status, disease process, and damage

Objective: To investigate outcome as measured by health status, disease process, and damage in an unselected group of patients with early rheumatoid arthritis (RA) monitored prospectively for 10 years and to search for prognostic factors. Patients and methods: 183 patients with RA with disease duration <2 years were assessed annually at a team care unit. Health status was measured by the Health Assessment Questionnaire (HAQ) and functional class. Disease process was assessed by clinical and laboratory measures of disease activity and evaluation of disease course. Damage was quantified as occurrence of major extra-articular manifestations and need for large joint replacements. Possible predictive factors were evaluated by logistic regression analyses. Results: 168/183 patients completed the entire follow up period. Of all 183 patients, 137 (75%) had been treated with disease modifying antirheumatic drugs and 84 (46%) with low dose oral glucocorticoids. After 10 years 158 patients (94%) managed daily life activities independently (functional class I–II). As measured by the HAQ 20% had almost no disability, 28% were mildly disabled, and 10% were seriously disabled. Median HAQ score had increased from 0.8 to 1.1 (p<0.001). Disease activity was significantly reduced. 133 patients (79%) had a relapsing remitting disease course and 30 patients (18%) were in remission as defined by the American College of Rheumatology criteria. Thirty patients (17%) had undergone large joint replacements. Fifteen patients (8%) had developed major extra-articular complications. The HAQ score during the first three months predicted disability at 10 years with an odds ratio of 13.4. Conclusions: Prospective studies such as this give important knowledge of the variable long term prognosis of RA and provide necessary background information for clinical trials of new treatment modalities.

Mortality in rheumatoid arthritis patients with disease onset in the 1980s

OBJECTIVE Several previous studies have shown increased mortality in rheumatoid arthritis (RA) patients. This study investigated if this was true also for patients with disease onset in the 1980s. PATIENTS AND METHODS The study group comprised 183 patients (67 men and 116 women) with definite RA participating in an ongoing prospective study. Mean age at onset of disease was 51 years, and mean duration of joint symptoms at inclusion was 11 months. The patients were included between 1985–89. Seventy five per cent of the patients were rheumatoid factor (RF) positive, 85% carried the shared epitope, and 90% became erosive. By 1 September 1997 the number and causes of death, obtained from the death certificates, were recorded. Standardised mortality ratio (SMR) was calculated, comparing the observed number of deaths in the cohort with the expected number of deaths in the general population in the same area, age and sex matched. The predictive values of demographics, genotype, RF status, and clinical data at baseline were estimated using the Cox proportional hazards regression model. RESULTS Eighteen patients (11 men and 7 women) had died compared with 20 expected deaths. SMR with 95% confidence intervals was 87 (53, 136). There was no significant increase in the number of deaths at any time during follow up for either sex. RA was not the main cause of death in any of the cases. By reading the patient charts two cases were found where RA or its treatment could have contributed to death. No RA related variable contributed significantly to an increased risk of death. CONCLUSION There was no increased mortality during the first 8–13 years of disease in this group of patients who developed RA in the 1980s.

Orthopaedic surgery in patients with rheumatoid arthritis over 20 years: prevalence and predictive factors of large joint replacement

Objective: To study the prevalence of orthopaedic surgery and to evaluate possible predictive factors for large joint replacements in patients with early rheumatoid arthritis (RA). Patients and methods: A cohort of 183 patients (116 (63.4%) female) with early RA was monitored for 16–20 years after recruitment during 1985–9. Mean (SD) age of patients 51.4 (12.4) years; mean (SD) duration of symptoms before inclusion 12 (7) months and mean (SD) duration of follow-up 16 (4) years. Occurrence of orthopaedic surgery was recorded continuously. A first prosthesis of a large joint (shoulder, elbow, wrist, hip, knee or ankle) was used as outcome variable in the predictive analyses. Results: In total, 386 orthopaedic interventions were performed in 106/183 (58%) patients during follow-up and a large joint replacement was performed in 44/183 (24%) patients. Using a Cox regression model, it was shown that Health Assessment Questionnaire, C-reactive protein and erythrocyte sedimentation rate at inclusion, and radiographic changes in small joints after 1 year, were associated with an increased risk of receiving prosthesis of large joints. Conclusion: In this cohort of patients with RA monitored from early disease stage, orthopaedic surgical procedures were performed in more than half of the patients. This included first large joint replacements in 24% of the cases. Easily available measures were identified as predictors of such joint replacements. This study could serve as a reference for comparison with cohorts of patients with RA recruited today, in which new more efficacious treatments are used.

Genetic studies on components of the Wnt signalling pathway and the severity of joint destruction in rheumatoid arthritis

Background Progression of joint destruction in rheumatoid arthritis (RA) is partly heritable; knowledge of genetic factors may increase our understanding of the mechanisms underlying joint destruction. The activity of the Wnt/β-catenin pathway influences osteoblast differentiation. Dickkopf-1 (Dkk-1) and sclerostin (Sost) are negative regulators and lipoprotein receptor-related protein-5 (LRP-5) and Kremen-1 are transmembrane receptors involved in this pathway. Objective To study variants in the genes encoding these proteins in relation to progression of joint destruction. Methods 1418 patients with RA of four cohorts with 4885 sets of hands and feet x-rays were studied. Explorative analyses were performed on 600 patients with RA from Leiden on single nucleotide polymorphisms (SNPs) tagging Dkk-1, Sost, Kremen-1 and LRP-5. SNPs significantly associating with joint damage progression were subsequently genotyped in cohorts from Groningen (NL), Sheffield (UK) and Lund (Sweden). Data were summarised in meta-analyses. Serum levels of functional Dkk-1 and sclerostin were measured and studied in relation to genotypes. Results In the first cohort, six Dkk-1, three Sost, one Kremen-1 and 10 LRP-5 SNPs were significantly associated with radiological progression of joint destruction. Three Dkk-1 SNPs were associated significantly with progression of joint damage in the meta-analysis, also after correction for multiple testing (rs1896368, rs1896367 and rs1528873). Two Sost SNPs tended to significance (rs4792909 and rs6503475, p=0.07 after false discovery rate correction). Gene–gene interactions between SNPs on Dkk-1 and Sost were seen. Serum levels of Dkk-1 were significantly correlated with the genotypes in rs1896368 (p=0.02). Conclusions Patients with RA carrying risk alleles of genetic variants in Dkk-1 have higher serum levels of functional Dkk-1 and more progressive joint destruction over time.

Genetic variants in IL15 associate with progression of joint destruction in rheumatoid arthritis: a multicohort study

Background Interleukin (IL)-15 levels are increased in serum, synovium and bone marrow of patients with rheumatoid arthritis (RA). IL-15 influences both the innate and the adaptive immune response; its major role is activation and proliferation of T cells. There are also emerging data that IL-15 affects osteoclastogenesis. The authors investigated the association of genetic variants in IL15 with the rate of joint destruction in RA. Method 1418 patients with 4885 x-ray sets of both hands and feet of four independent data sets were studied. First, explorative analyses were performed on 600 patients with early RA enrolled in the Leiden Early Arthritis Clinic. Twenty-five single-nucleotide polymorphisms (SNPs) tagging IL-15 were tested. Second, SNPs with significant associations in the explorative phase were genotyped in data sets from Groningen, Sheffield and Lund. In each data set, the relative increase of the progression rate per year in the presence of a genotype was assessed. Subsequently, data were summarised in an inverse weighting meta-analysis. Results Five SNPs were significantly associated with rate of joint destruction in phase 1 and typed in the other data sets. Patients homozygous for rs7667746, rs7665842, rs2322182, rs6821171 and rs4371699 had respectively 0.94-, 1.04-, 1.09-, 1.09- and 1.09-fold rate of joint destruction compared to other patients (p=4.0×10−6, p=3.8×10−4, p=5.0×10−3, p=5.0×10−3 and p=9.4×10−3). Discussion Independent replication was not obtained, possibly due to insufficient power. Meta-analyses of all data sets combined resulted in significant results for four SNPs (rs7667746, p<0.001; rs7665842, p<0.001; rs4371699, p=0.01; rs6821171, p=0.01). These SNPs were also significant after correction for multiple testing. Conclusion Genetic variants in IL-15 are associated with progression of joint destruction in RA.

Increased plasma levels of the soluble Mer tyrosine kinase receptor in systemic lupus erythematosus relate to disease activity and nephritis

IntroductionMer and Tyro3 are receptor tyrosine kinases important for the phagocytosis of apoptotic cells. Together with Axl, they constitute the TAM receptor family. These receptors can be shed from the cell membrane and their soluble extracellular regions can be found in plasma. The objective of this study was to elucidate whether the plasma levels of soluble Mer (sMer) and Tyro3 (sTyro3) were increased in systemic lupus erythematosis (SLE), rheumatoid arthritis (RA), or critical limb ischemia (CLI).MethodsELISA kits were used to test plasma concentrations in controls and in patients with SLE, RA or CLI.ResultsIncreased levels of, in particular, sMer and, to some extent, sTyro3, were found in patients with SLE or RA, but not in patients with CLI. Patients with SLE demonstrated the highest sMer levels and there was a strong correlation to higher SLE disease activity score (SLEDAI). In contrast, in patients with RA, the sMer levels did not correlate with the disease activity score (DAS). In SLE, sMer levels were particularly high in those with lupus nephritis, patients who also had decreased C1q levels and increased titers of anti-DNA antibodies. After therapy, the plasma concentrations of sMer decreased in parallel to the decrease in SLEDAI score.ConclusionsThe plasma concentrations of sMer and sTyro3 were significantly increased in patients with active SLE and RA, suggesting the TAM receptor shedding was affected by these autoimmune diseases. In particular, sMer was increased in SLE, the plasma levels of sMer reflecting disease activity.

Prevalence and predictive factors of comorbidity in rheumatoid arthritis patients monitored prospectively from disease onset up to 20 years: lack of association between inflammation and cardiovascular disease

Objectives: To study the prevalence of comorbid conditions at diagnosis and during follow-up in a cohort of patients with early rheumatoid arthritis (RA) followed prospectively over 20 years, and to identify possible early predictive factors for future comorbidities. Methods: A community-based cohort of 183 patients (mean age 52 years, 63% female) with early RA was recruited between 1985 and 1989. The presence of comorbidity at RA diagnosis and the occurrence of additional comorbidities were recorded continuously. Possible predictors of future comorbidities were analysed using the Cox proportional hazards model. Results: At RA diagnosis, at least one comorbid condition was present in 43% of the patients. Cardiovascular diseases (CVDs), including hypertension (16% of patients) and malignancy (6% of patients), were most common. In total, 82% of patients developed additional comorbidities during follow-up. CVD and malignancies remained the most frequent comorbidities. Higher age [p < 0.001, odds ratio (OR) 1.03, 95% confidence interval (CI) 1.01–1.15] and the presence of any comorbidity at diagnosis (p = 0.02; OR 1.64, 95% CI 1.08–2.52) predicted future comorbidity. Measures of inflammation at diagnosis or during follow-up were not predictive for development of CVD. Conclusion: Comorbidity was present in a considerable proportion of patients in this cohort. More than 40% of patients had another disease at inclusion and during follow-up and > 80% developed additional conditions. The pattern of comorbidity remained unchanged, with CVD and malignancy being most common. Older age and the presence of comorbidity at RA diagnosis predicted the development of comorbidities. The degree of inflammation at any time point was not predictive of future CVD.

Smoking as a risk factor for the radiological severity of rheumatoid arthritis: a study on six cohorts

Background Smoking is a risk factor for the development of anti -citrullinated protein antibodies (ACPA) positive rheumatoid arthritis (RA). Whether smoking predisposes to severe joint damage progression is not known, since deleterious, protective and neutral observations have been made. Objective To determine the effect of smoking on joint damage progression. Methods Smoking status was assessed in 3158 RA patients included in six cohorts (Leiden Early Arthritis Clinic (Leiden-EAC), BARFOT, Lund, Iceland, NDB and Wichita). In total 9412 radiographs were assessed. Multivariate normal regression and linear regression analyses were performed. Data were summarised in a random effects inverse variance meta-analysis. Results When comparing radiological progression for RA patients that were never, past and current smokers, smoking was significantly associated with more severe joint damage in Leiden-EAC (p=0.042) and BARFOT (p=0.015) RA patients. No significant associations were found in the other cohorts, though a meta-analysis on the six cohorts showed significantly more severe joint damage progression in smokers (p=0.01). Since smoking predisposes to ACPA, analyses were repeated with ACPA as additional adjustment factor. Then the association was lost (meta-analysis p=0.29). Conclusions This multi-cohort study indicated that the effect of smoking on joint damage is mediated via ACPA and that smoking is not an independent risk factor for radiological progression in RA.