Citations

Abstract In rheumatoid arthritis (RA), tissue-infiltrating lymphocytes can be arranged in sophisticated organizations that resemble microstructures usually formed in secondary lymphoid organs. Molecular pathways and host risk factors involved in this process of lymphoid neogenesis remain to be defined. In a series of 64 synovial tissue biopsies, lymphoid follicles with germinal centers (GCs) were found in 23.4% of the patients. Follicular dendritic cells (FDCs) were exclusively present in tissues with GCs, suggesting that the recruitment or in situ maturation of FDCs is a critical factor for GC formation in the synovial membrane. Primary follicles were absent, emphasizing the role of Ag recognition in the generation of inflammation-associated lymphoid organogenesis. Multivariate logistic regression analysis of tissue cytokines and chemokines identified two parameters, in situ transcription of lymphotoxin (LT)-β and of B lymphocyte chemoattractant (BLC; BLC/CXCL13), that were predictors for FDC recruitment and synovial GC formation. LT-β and BLC/CXCL13 were found to be independent variables that could, in part, compensate for each other to facilitate GC formation. Prediction models incorporating in situ transcription of LT-β and BLC/CXCL13 had high negative yet moderate positive predictive values, suggesting that LT-β and BLC/CXCL13 are necessary but not sufficient. LT-β protein was detected on a subset of mantle zone and GC B cells, but also on T cells in follicular structures. BLC/CXCL13 was produced by FDCs in follicular centers, but was predominantly found in endothelial cells and synovial fibroblasts, suggesting heterotypic signaling between cells of the synovial membrane and infiltrating lymphocytes in regulating extranodal lymphoid neogenesis.

Objective: We investigated ADAMTS13 (a disintegrin-like and metalloprotease with thrombospondin type 1 motif, member 13) messenger RNA levels as a biomarker of disease features in systemic lupus erythematosus. Methods: We measured and compared messenger RNA (mRNA) levels of ADAMTS13 in peripheral blood cells in patients with systemic lupus erythematosus and healthy control subjects by whole-genome microarray. We retrospectively analyzed the correlations of ADAMTS13 mRNA expression with clinical features, laboratory parameters, therapeutic features, and disease activity (according to the Systemic Lupus Erythematosus Disease Activity Index). We also examined the association of three single nucleotide polymorphisms (rs4962145, rs2285467, and rs685523) of the ADAMTS13 gene with patient characteristics. Results: In 309 patients, the median ADAMTS13 mRNA expression levels were significantly higher in blood cells of systemic lupus erythematosus patients than in 23 healthy controls ( p = .03). Notably, ADAMTS13 mRNA expression levels were significantly higher in systemic lupus erythematosus patients with a history of stroke ( p = .02) or transient ischemic attack ( p = .02). Among the three single nucleotide polymorphisms analyzed, rs2285467 was significantly associated with stroke ( p = .03) and anticardiolipin antibodies ( p = .04). Conclusions: Increased expression of ADAMTS13 mRNA in blood cells is associated with the presence of ischemic cerebrovascular disease in systemic lupus erythematosus patients and suggests a potential role for ADAMTS13 in the pathogenesis of ischemic cerebrovascular disease in these patients.

Objective A very few studies describe the epidemiology of primary Sjögren's syndrome (pSS). The reported frequency of pulmonary involvement in pSS varies widely depending on the detection method employed, and consists mainly of various forms of airways disease. We aimed to evaluate the incidence and mortality of pSS and of lung disease in pSS, focusing on interstitial lung disease (ILD). Methods A population-based incidence cohort of patients diagnosed with pSS in 1976–2005 was assembled. Diagnosis was based on the 2002 American-European Consensus Group criteria for pSS. Cumulative incidence adjusted for the competing risk of death was estimated. A Cox model with a time-dependent covariate was used to determine the incidence and the standardised mortality HR of pSS. Results 85 patients with pSS were identified (mean age 59.9 years; 91% women). The annual incidence of pSS was 4.2, 95% CI (3.3 to 5.1)/100 000 population and it increased with higher age at pSS diagnosis (18–44 years: 2.1/100 000 vs ≥75 years: 12.3/100 000). Standardised mortality ratio in pSS compared with the general population was 0.92, 95% CI (0.57 to 1.41). A total of 105 patients with pSS and ILD were identified (mean age 58.1 years; 91% women). Among patients with pSS without prior ILD, the cumulative incidence of ILD in patients with pSS was 10% (±3%) at 1 year after diagnosis of pSS and increased to 20% (±4%) by 5 years after pSS. The development of lung disease in pSS was associated with poor survival (HR 2.16; 95% CI 0.99 to 4.74). Conclusions pSS incidence seems to be almost the same as was reported in a previous study conducted among Olmsted County Minnesota population. Survival among patients with pSS and general population does not differ substantially. However, patients with pSS who have ILD likely have increased premature mortality.

Current methods used to assess calibration are limited, particularly in the assessment of prognostic models. Methods for testing and visualizing calibration (e.g. the Hosmer–Lemeshow test and calibration slope) have been well thought out in the binary regression setting. However, extension of these methods to Cox models is less well known and could be improved. We describe a model-based framework for the assessment of calibration in the binary setting that provides natural extensions to the survival data setting. We show that Poisson regression models can be used to easily assess calibration in prognostic models. In addition, we show that a calibration test suggested for use in survival data has poor performance. Finally, we apply these methods to the problem of external validation of a risk score developed for the general population when assessed in a special patient population (i.e. patients with particular comorbidities, such as rheumatoid arthritis).

ObjectiveTo determine whether the impact of aging on cardiovascular disease (CVD) risk in patients with rheumatoid arthritis (RA) differs from that in the general population (as estimated by the Framingham Risk Score [FRS]).MethodsA population‐based inception cohort of Olmsted County, Minnesota residents ages ≥30 years who fulfilled the American College of Rheumatology 1987 criteria for RA in 1988–2008 was assembled and followed up until death, migration, or July 1, 2012. Data on CVD events were collected by medical records review. The 10‐year FRS for CVD was calculated. Cox models adjusted for FRS were used to examine the influence of age on CVD risk.ResultsThe study included 563 patients with RA without prior CVD (mean age 55 years, 72% women, and 69% seropositive [i.e., rheumatoid factor and/or anti–citrullinated protein antibody positive]). During a mean followup of 8.2 years, 98 patients developed CVD (74 seropositive and 24 seronegative), but the FRS predicted only 59.7 events (35.4 seropositive and 24.3 seronegative). The gap between observed and predicted CVD risk increased exponentially across age, and the effect of age on CVD risk in seropositive RA was nearly double its effect in the general population, with additional log(age) coefficients of 2.91 for women (P = 0.002) and 2.06 for men (P = 0.027).ConclusionOur findings indicate that age exerts an exponentially increasing effect on CVD risk in seropositive RA, but no increased effect among seronegative patients. The causes of accelerated aging in patients with seropositive RA deserve further investigation.

ObjectiveTo examine lipid profiles among statin‐naive patients with rheumatoid arthritis (RA) and those without RA before and after the initiation of statins.MethodsInformation regarding lipid measures and statin use was gathered in a population‐based incident cohort of patients with RA (1987 American College of Rheumatology criteria first met between January 1, 1988 and January 1, 2008) and in a cohort of non‐RA subjects from the same underlying population. Only patients with no prior history of statin use were included.ResultsThe study included 161 patients with RA (mean age 56.3 years, 57% female) and 221 non‐RA subjects (mean age 56.0 years, 66% female). Prior to the start of statins, the levels of total cholesterol and low‐density lipoprotein (LDL) cholesterol were lower in the RA versus the non‐RA cohort (P < 0.001 and P = 0.003, respectively). The absolute and percentage change in LDL cholesterol after at least 90 days of statin use tended to be smaller in the RA versus the non‐RA cohort (P = 0.03 and P = 0.09, respectively). After at least 90 days of statin use, patients with RA were less likely to achieve therapeutic goals for LDL cholesterol than the non‐RA subjects (P = 0.046). Increased erythrocyte sedimentation rate (ESR) at baseline (odds ratio 0.47, 95% confidence interval 0.26–0.85) was associated with lower likelihood of achieving therapeutic LDL goals.ConclusionPatients with RA had lower total cholesterol and LDL cholesterol levels before statin initiation and lower likelihood of achieving therapeutic LDL goals following statin use than the non‐RA subjects. Some RA disease characteristics, in particular ESR at baseline, may have an adverse impact on achieving therapeutic LDL goals.

ObjectiveTo study left ventricular (LV) geometry in patients with rheumatoid arthritis (RA) and no history of heart failure compared with that in subjects with neither RA nor a history of heart failure, and to determine the impact of RA on LV remodeling.MethodsA cross‐sectional, community‐based study was conducted among adult (age ≥50 years) patients with RA and age‐ and sex‐matched subjects with neither RA nor a history of heart failure. All participants underwent standard 2‐dimensional Doppler echocardiography. LV geometry was classified into the following 4 categories based on relative wall thickness and sex‐specific cutoffs for the LV mass index: concentric remodeling, concentric hypertrophy, eccentric hypertrophy, or normal geometry.ResultsAmong 200 patients with RA and 600 age‐ and sex‐matched subjects without RA, the mean age was 65 years, and 74% of the individuals in both cohorts were female. Compared with subjects without RA, patients with RA were significantly more likely to have abnormal LV geometry (odds ratio [OR] 1.44, 95% confidence interval [95% CI] 1.03–2.00), even after adjusting for cardiovascular risk factors and comorbidities. Among subjects with abnormal LV geometry, the odds of concentric LV remodeling were significantly increased in patients with RA (OR 4.73, 95% CI 2.85–7.83). In linear regression analyses, the LV mass index appeared to be lower in patients with RA who were currently receiving corticosteroids (β ± SE −0.082 ± 0.027, P = 0.002), even after adjusting for cardiovascular risk factors and comorbidities.ConclusionRA was strongly associated with abnormal LV remodeling (particularly concentric LV remodeling) among RA patients without heart failure. This association remained significant after adjustment for cardiovascular risk factors and comorbidities. RA disease–related factors may promote changes in LV geometry. The biologic mechanisms underlying LV remodeling warrant further investigation.

ObjectivePulmonary disease represents an important extraarticular manifestation of rheumatoid arthritis (RA). While the association of RA and interstitial lung disease is widely acknowledged, obstructive lung disease (OLD) in RA is less well understood. We therefore aimed to assess the incidence, risk factors, and mortality of OLD in patients with RA.MethodsWe examined a population‐based incident cohort of patients with RA and a comparison cohort of individuals without RA. OLD was defined using a strict composite criterion. Cox proportional hazards models were used to compare OLD incidence between the RA and comparator cohorts to investigate risk factors and to explore the impact of OLD on patient survival.ResultsA total of 594 patients with RA and 596 subjects without RA were followed for a mean of 16.3 and 19.4 years, respectively. The lifetime risk of developing OLD was 9.6% for RA patients and 6.2% for subjects without RA (hazard ratio [HR] 1.54, 95% confidence interval [95% CI] 1.01–2.34). The risk of developing OLD was higher among male patients, among current or former smokers, and for individuals with more severe RA. Survival of RA patients diagnosed with OLD was worse compared to those without OLD (HR 2.09, 95% CI 1.47–2.97).ConclusionPatients with RA are at higher risk of developing OLD, which is significantly associated with premature mortality. Effective diagnostic and therapeutic strategies to detect and manage OLD in patients with RA may help to improve survival in these patients.