Serum alarmins and the risk of incident interstitial lung disease in rheumatoid arthritis.

OBJECTIVES: To quantify associations of serum alarmins with risk of rheumatoid arthritis-associated interstitial lung disease (RA-ILD). METHODS: Using serum collected at enrolment, three alarmins (interleukin [IL]-33, thymic stromal lymphopoietin [TSLP], and IL-25) were measured in a multicentre prospective RA cohort. ILD was classified using systematic medical record review. Cross-sectional associations of log-transformed (IL-33, TSLP) or quartile (IL-25) values with RA-ILD at enrolment (prevalent RA-ILD) were examined using logistic regression, while associations with incident RA-ILD developing after enrolment were examined using Cox proportional hazards. Covariates in multivariate models included age, sex, race, smoking status, RA disease activity score, and anti-cyclic citrullinated antibody positivity. RESULTS: Of 2,835 study participants, 115 participants (4.1%) had prevalent RA-ILD at baseline and an additional 146 (5.1%) developed incident ILD. There were no associations between serum alarmin concentrations and prevalent ILD in unadjusted or adjusted logistic regression models. In contrast, there was a significant inverse association between IL-33 concentration and the risk of developing incident RA-ILD in unadjusted (HR 0.73 per log-fold increase; 95% CI 0.57-0.95; p= 0.018) and adjusted (HR 0.77; 95% CI 0.59-1.00, p= 0.047) models. No significant associations of TSLP or IL-25 with incident ILD were observed. CONCLUSIONS: In this study, we observed a significant inverse association between serum IL-33 concentration and the risk of developing incident RA-ILD, but no associations with prevalent ILD. Additional investigation is required to better understand the mechanisms driving this relationship and how serum alarmin IL-33 assessment might contribute to clinical risk stratification in patients with RA.

Neutrophil-to-Lymphocyte Ratio and Platelet-to-Lymphocyte Ratio as Biomarkers in Axial Spondyloarthritis: Observational Studies From the Program to Understand the Longterm Outcomes in Spondyloarthritis Registry.

OBJECTIVES: This study was conducted to assess the utility of neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) in predicting radiographic sacroiliitis and active disease in axial spondyloarthritis (SpA) and to explore the association between use of a tumor necrosis factor inhibitor (TNFi) and these laboratory values compared with traditional inflammatory markers. METHODS: Observational data from the Program to Understand the Longterm Outcomes in Spondyloarthritis (PULSAR) registry were analyzed. We generated receiver operating characteristic curves to calculate laboratory cutoff values; we used these values in multivariable logistic regression models to identify associations with radiographically confirmed sacroiliitis and active disease. We also used logistic regression to determine the likelihood of elevated laboratory values after initiation of TNFi. RESULTS: Most study participants (n = 354) were White, male, and HLA-B27 positive. NLR (odds ratio [OR] 1.459, P = 0.034), PLR (OR 4.842, P < 0.001), erythrocyte sedimentation rate (OR 4.397, P < 0.001), and C-reactive protein (CRP) level (OR 2.911, P = 0.001) were independent predictors of radiographic sacroiliitis. Models that included PLR with traditional biomarkers performed better than those with traditional biomarkers alone. NLR (OR 6.931, P = 0.002) and CRP (OR 2.678, P = 0.004) were predictors of active disease, but the model that included both NLR and CRP performed better than CRP alone. TNFi use reduced the odds of elevated NLR (OR 0.172, P < 0.001), PLR (OR 0.073, P < 0.001), erythrocyte sedimentation rate (OR 0.319, P < 0.001), and CRP (OR 0.407, P < 0.001), but models that included NLR or PLR and traditional biomarkers performed best. CONCLUSIONS: These findings demonstrate an association between NLR and PLR and sacroiliitis and disease activity, with NLR and PLR showing response after TNFi treatment and adding useful clinical information to established biomarkers, thus perhaps assisting in management of axial SpA.

Genetic, social, and environmental risk factors in rheumatoid arthritis-associated interstitial lung disease.

OBJECTIVE: MUC5B and TOLLIP single nucleotide polymorphisms (SNPs) and cigarette smoking were associated with rheumatoid arthritis-interstitial lung disease (RA-ILD) in a predominantly Northern European population. We evaluated whether RA-ILD is associated with these genetic variants and HLA-DRB1 shared epitope (SE) alleles in a large RA cohort stratified by race and smoking history. METHODS: HLA-DRB1 SE alleles and MUC5B rs35705950 and TOLLIP rs5743890 SNPs were genotyped in U.S. veterans with RA. ILD was validated through medical record review. Genetic associations with ILD were assessed in logistic regression models overall and in subgroups defined by race and smoking status, with additive interactions assessed by the relative excess risk of interaction (RERI). RESULTS: Of 2,556 participants (88% male, 77% White), 238 (9.3%) had ILD. The MUC5B variant was associated with ILD (OR 2.25 [95% CI 1.69, 3.02]), whereas TOLLIP and HLA-DRB1 SE were not. The MUC5B variant was less frequent among Black/African American participants (5.8% vs. 22.6%), though its association with RA-ILD was numerically stronger (OR 4.23 [1.65, 10.86]) compared to all other participants (OR 2.32 [1.70, 3.16]). Those with the MUC5B variant and a smoking history had numerically higher odds of ILD (OR 4.18 [2.53, 6.93]) than non-smokers (OR 2.41 [1.16, 5.04]). Additive interactions between MUC5B-race and MUC5B-smoking were not statistically significant. CONCLUSION: In this large RA cohort, the MUC5B promoter variant was associated with >2-fold higher odds of RA-ILD. While this variant is less common among Black/African American patients, its presence in this population carried >4-fold higher odds of RA-ILD.

The impact of disease severity measures on survival in U.S. veterans with rheumatoid arthritis-associated interstitial lung disease.

OBJECTIVES: To determine whether RA and interstitial lung disease (ILD) severity measures are associated with survival in patients with RA-ILD. METHODS: We studied US veterans with RA-ILD participating in a multicentre, prospective RA cohort study. RA disease activity (28-joint DAS [DAS28-ESR]) and functional status (multidimensional HAQ [MDHAQ]) were collected longitudinally while pulmonary function tests (forced vital capacity [FVC], diffusing capacity for carbon monoxide) were obtained from medical records. Vital status and cause of death were determined from the National Death Index and administrative data. Predictors of death were assessed using multivariable Cox regression models adjusting for age, sex, smoking status, ILD duration, comorbidity burden and medications. RESULTS: We followed 227 RA-ILD participants (93% male and mean age of 69 years) over 1073 person-years. Median survival after RA-ILD diagnosis was 8.5 years. Respiratory diseases (28%) were the leading cause of death, with ILD accounting for 58% of respiratory deaths. Time-varying DAS28-ESR (adjusted hazard ratio [aHR] 1.21; 95% CI: 1.03, 1.41) and MDHAQ (aHR 1.85; 95% CI: 1.29, 2.65) were separately associated with mortality independent of FVC and other confounders. Modelled together, the presence of either uncontrolled disease activity (moderate/high DAS28-ESR) or FVC impairment (<80% predicted) was significantly associated with mortality risk. Those with a combination of moderate/high disease activity and FVC <80% predicted had the highest risk of death (aHR 4.43; 95% CI: 1.70, 11.55). CONCLUSION: Both RA and ILD disease severity measures are independent predictors of survival in RA-ILD. These findings demonstrate the prognostic value of monitoring the systemic features of RA-ILD.

Tumor necrosis factor inhibitor (TNFi) persistence and reasons for discontinuation in a predominantly male cohort with axial spondyloarthritis.

Although tumor necrosis factor inhibitors (TNFi) have favorably altered the treatment landscape for patients with axial spondyloarthritis (axSpA), there is limited data regarding TNFi persistence and reasons for discontinuation. This is an observational time-to-event study utilizing data collected for a prospective multiple-disease registry of US Veterans with axSpA treated with TNFi therapies and recruited over a 10 year period. Clinical, serological, and comorbid parameters were collected. Corporate Data Warehouse Pharmacy files provided courses of the 5 TNFi agents, and response to treatment was documented. Individual TNFi persistence was established utilizing univariate and multivariate Cox proportional models, and reasons for discontinuation were obtained by physician chart review. Two-hundred and fifty-five axSpA patients received 731 TNFi courses. A majority of patients (84.3%) had TNFi persistence at 12 months; 63.5% and 47.1% at 24 and 36 months, respectively. Compared to adalimumab, infliximab demonstrated greater persistence, certolizumab the least. Age, smoking status, BMI, comorbidity burden, inflammatory markers and HLA-B27 did not predict TNFi persistence or discontinuation. Stroke and peripheral arterial disease increased the probability of TNFi discontinuation. Secondary non-response (SNR) was the most common reason for discontinuation (46% of all courses); non-adherence (6%) and clinical remission (2%) were uncommon. Pain score at enrollment, myocardial infarction, African American race and inflammatory bowel disease (IBD) predicted TNFi response. While initial persistence of TNFi treatment was high, a large proportion of the patients discontinued initial TNFi therapy by 3 years, primarily due to loss of efficacy. While further research identifying potential predictors of TNFi discontinuation in axSpA is warranted, access to alternate disease-modifying therapies is needed.

Associations of serum cytokines and chemokines with the risk of incident cancer in a prospective rheumatoid arthritis cohort.

OBJECTIVES: We aimed to assess whether serum cytokine/chemokine concentrations predict incident cancer in RA patients. METHODS: Data from cancer-free enrollees in the Veterans Affairs Rheumatoid Arthritis (VARA) Registry were linked to a national VA oncology database and the National Death Index (NDI) to identify incident cancers. Seventeen serum cytokines/chemokines were measured from enrollment serum and an overall weighted cytokine/chemokine score (CK score) was calculated. Associations of cytokines/chemokines with all-site, lung, and lymphoproliferative cancers were assessed in Cox regression models accounting for relevant covariates including age, sex, RA disease activity, and smoking. RESULTS: In 1216 patients, 146 incident cancers (42 lung and 23 lymphoproliferative cancers) occurred over 10,072 patient-years of follow-up with a median time of 4.6 years from enrollment (cytokine/chemokine measurement) to cancer incidence. In fully adjusted models, CK score was associated with a higher risk of all-site (aHR 1.32, 95% CI 1.01-1.71, p < 0.001), lung (aHR 1.81, 1.40-2.34, p = 0.001), and lung/lymphoproliferative (aHR 1.54 [1.35-1.75], p < 0.001) cancer. The highest quartile of CK score was associated with a higher risk of all-site (aHR 1.91, 0.96-3.81, p = 0.07; p-trend = 0.005), lung (aHR 8.18, 1.63-41.23, p = 0.01; p-trend < 0.001), and lung/lymphoproliferative (aHR 4.56 [1.84-11.31], p = 0.001; p-trend < 0.001) cancer. Thirteen of 17 individual analytes were associated with incident cancer risk. CONCLUSION: Elevated cytokine/chemokine concentrations are predictive of future cancer in RA patients, particularly lung and lymphoproliferative cancers. These results suggest that the measurement of circulating cytokines/chemokines could be informative in cancer risk stratification and could provide insight into future cancer prevention strategies in RA, and possibly individuals without RA.

Association of Agricultural, Occupational, and Military Inhalants With Autoantibodies and Disease Features in US Veterans With Rheumatoid Arthritis.

OBJECTIVE: To determine the association of inhalant exposures with rheumatoid arthritis (RA)-related autoantibodies and severity in US veterans. METHODS: Participants in the Veterans Affairs Rheumatoid Arthritis (VARA) registry were mailed surveys assessing occupational, agricultural, and military inhalant exposures. Demographic characteristics, disease activity, functional status, and extraarticular features were obtained from the VARA registry, while HLA-DRB1 shared epitope (SE) status, anti-cyclic citrullinated peptide (anti-CCP) antibodies, and rheumatoid factor (RF) were measured using banked DNA/serum from enrollment. Associations between inhalant exposures and RA-related factors (autoantibodies, severity, and extraarticular features) were assessed using multivariable linear and logistic regression models adjusted for age, sex, race, and tobacco use and stratified by SE status. Adjusted odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated. RESULTS: Questionnaires were returned by 797 of 1,566 participants (50.9%). Survey respondents were older, more often White or male, and less frequently smokers, and had lower disease activity compared to nonrespondents. Anti-CCP positivity was more common among veterans exposed to burn pits (OR 1.66 [95% CI 1.02, 2.69]) and military waste disposal (OR 1.74 [95% CI 1.04, 2.93]) independent of other factors. Among participants who were positive for SE alleles, burn pit exposure (OR 5.69 [95% CI 2.73, 11.87]) and military waste disposal exposure (OR 5.05 [95% CI 2.42, 10.54]) were numerically more strongly associated with anti-CCP positivity. Several inhalant exposures were associated with the presence of chronic lung disease, but not with the presence of RF or the level of disease activity. CONCLUSION: Military burn pit exposure and military waste disposal exposure were independently associated with the presence of anti-CCP antibodies in RA patients. These findings are consistent with emerging evidence that various inhalant exposures influence autoantibody expression and RA risk.

Comparative Profiling of Serum Protein Biomarkers in Rheumatoid Arthritis-Associated Interstitial Lung Disease and Idiopathic Pulmonary Fibrosis.

OBJECTIVE: Interstitial lung disease (ILD) is a frequent complication of rheumatoid arthritis (RA), occurring in up to 40% of patients during the course of their disease. Early diagnosis is critical, particularly given the shared clinicoepidemiologic features between advanced rheumatoid arthritis-associated ILD (RA-ILD) and idiopathic pulmonary fibrosis (IPF). This study was undertaken to define the molecular basis of this overlap through comparative profiling of serum proteins in RA-ILD and IPF. METHODS: Multiplex enzyme-linked immunosorbent assays (ELISAs) were used to profile 45 protein biomarkers encompassing cytokines/chemokines, growth factors, and matrix metalloproteinases (MMPs) in sera obtained from RA patients with ILD and those without, individuals with IPF, and healthy controls. Levels of selected serum proteins were compared between patient subgroups using adjusted linear regression, principal component analysis (PCA), and least absolute shrinkage and selection operator (LASSO) modeling. RESULTS: Multiplex ELISA-based assessment of sera from 2 independent cohorts (Veterans Affairs [VA] and Non-VA) revealed a number of non-overlapping biomarkers distinguishing RA-ILD from RA without ILD (RA-no ILD) in adjusted regression models. Parallel analysis of sera from IPF patients also yielded a discriminatory panel of protein markers in models adjusted for age/sex/smoking, which showed differential overlap with profiles linked to RA-ILD in the VA cohort versus the Non-VA cohort. PCA revealed several distinct functional groups of RA-ILD-associated markers that, in the VA cohort, encompassed proinflammatory cytokines/chemokines as well as 2 different subsets of MMPs. Finally, LASSO regression modeling in the Non-VA and VA cohorts revealed distinct biomarker combinations capable of discriminating RA-ILD from RA-no ILD. CONCLUSION: Comparative serum protein biomarker profiling represents a viable method for distinguishing RA-ILD from RA-no ILD and identifying population-specific mediators shared with IPF.

Exposure to ambient air pollution and autoantibody status in rheumatoid arthritis.

OBJECTIVE: To evaluate the relationship between air pollutant (AP) exposure and rheumatoid arthritis (RA) autoantibody status METHODS: We performed a cross sectional study utilizing enrollment data from participants in the Veterans Affairs rheumatoid arthritis registry. HLA-DRB1 shared epitope (SE), smoking, rheumatoid factor (RF), and anti-cyclic citrullinated peptide antibody (ACPA) status were collected. Mean exposure levels were obtained for AP (NO2, SO2, particulate matter [PM2.5, PM10], and ozone) from air quality monitoring stations at patients' residential zip codes in the year prior to enrollment. Multivariable logistic and ordinary least squares regression models were used to determine independent associations of AP with RA seropositivity and autoantibody concentration. RESULTS: The cohort included 557 veterans (90% male, 76% Caucasian), with mean age of 70 years and mean disease duration of 13 years. The majority were HLA-DRB1 SE, RF, and ACPA positive (73%, 79%, and 76%, respectively). In univariate models, PM2.5 exposure was associated with higher ACPA concentration (p = 0.009). Similarly, in multivariable regression models, PM2.5 exposure was independently associated with higher ACPA concentration (p = 0.037). Current smoking independently predicted RF and ACPA positivity and titers, while HLA-DRB1 SE alleles were associated with RF positivity and ACPA positivity and titers. CONCLUSIONS: In an elderly cohort of RA patients, fine particulate matter (PM2.5) exposure independently predicted higher ACPA concentration. Further study of fine particulate matter in the pathogenesis of RA is warranted. Key Points • A study that integrates both genetic and environmental exposure data, relative to RA autoantibody status. • Of different air pollutants measures, exposure to fine particulate matter (PM2.5) appears to be most closely linked to ACPA titers.

Biologic and Glucocorticoid Use after Methotrexate Initiation in Patients with Rheumatoid Arthritis.

OBJECTIVE: Biologic therapies can improve disease control for patients with rheumatoid arthritis (RA) but may be both overused and underused. We aimed to identify predictors of greater use of biologic therapies and to identify factors associated with persistent glucocorticoid use. METHODS: Using national US Veteran's Affairs databases 2005-2016, we identified patients with RA receiving a first-ever prescription of methotrexate (MTX), requiring ≥ 6 months of baseline data. We evaluated predictors of biologic therapy initiation within 2 years of starting MTX and factors associated with baseline and persistent glucocorticoid use at 6-12 months using multivariable models. RESULTS: Among 17,415 patients starting MTX, 3263 patients received biologic therapy within 2 years (20.6% 2-yr incidence). In adjusted analyses, biologic use was substantially lower in older patients [e.g., aHR 0.20 (95% CI 0.16, 0.26) for patients ≥ 80 vs < 50] and patients with more comorbidities [aHR 0.79 (95% CI 0.72, 0.87) for Charlson score ≥ 3 vs < 3]. Patients with heart failure [aHR 0.68 (95% CI 0.54, 0.84)], cancer [aHR 0.78 (95% CI 0.66, 0.92)], or who were nonwhite [aHR 0.79 (95% CI 0.72, 0.87)] were also less likely to receive a biologic. In contrast, baseline and persistent glucocorticoid use was similar across age groups and more common in patients with greater comorbidity. CONCLUSION: Biologic therapy is initiated less frequently in patients with RA who are older, have more comorbidities, and who are nonwhite. While biologics may be avoided in older and sicker patients because of safety concerns, glucocorticoid use is similar regardless of age and is more frequent in patients with comorbidities, with implications for patient outcomes.

Chronic lung disease in U.S. Veterans with rheumatoid arthritis and the impact on survival.

Assess the impact of chronic lung diseases (CLD) on survival in rheumatoid arthritis (RA). Among participants in the Veterans Affairs Rheumatoid Arthritis (VARA) Registry, a prospective cohort of U.S. Veterans with RA, we identified CLD and cardiovascular disease (CVD) using administrative and registry data. Demographics, smoking status, RA characteristics including Disease Activity Score in 28 joints (DAS28), and disease-modifying anti-rheumatic drug (DMARD) use were obtained from registry data, which were linked to the National Death Index to obtain vital status. We evaluated associations of CLD with survival using the multivariable Cox regression models. Among a large (n = 2053), male-predominant (91%) RA cohort, 554 (27%) had CLD at enrollment. Mortality risk was increased 1.51-fold (95% CI 1.26-1.81) in RA patients with CLD after multivariable adjustment, a risk that was similar to that observed with CVD (HR CLD alone 1.46 [1.03-2.06]; CVD alone 1.62 [1.35-1.94]). Survival was significantly reduced in those with interstitial lung disease (ILD) as well as other forms of CLD. Mortality risk with methotrexate and biologic use was not different in those with CLD compared to those without (p interaction ≥ 0.15) using multiple exposure definitions and propensity score adjustment. Mortality risk is significantly increased in RA patients with CLD. This risk is attributable not only to ILD but also to other chronic lung conditions and does not appear to be substantially greater in those receiving methotrexate or biologic therapies. Comorbid lung disease should be targeted as a means of improving long-term outcomes in RA.

Body Mass Index, Weight Loss, and Cause-Specific Mortality in Rheumatoid Arthritis.

OBJECTIVE: To examine associations of body mass index (BMI) and weight loss with cause-specific mortality in rheumatoid arthritis (RA). METHODS: A cohort of US veterans with RA was followed until death or through 2013. BMI was categorized as underweight, normal, overweight, and obese. Weight loss was calculated as the 1) annualized rate of change over the preceding 13 months, and 2) cumulative percent. Vital status and cause of death were obtained from the National Death Index. Multivariable competing-risks regression models were utilized to assess the time-varying associations of BMI and weight loss with cause-specific mortality. RESULTS: Among 1,600 participants and 5,789 patient-years of followup, 303 deaths occurred (95 cardiovascular, 74 cancer, and 46 respiratory). The highest weight-loss rate and weight-loss percent were associated with a higher risk of cardiovascular mortality (rate: subdistribution hazard ratio [sHR] 2.27 [95% confidence interval (95% CI) 1.61-3.19]; percent: sHR 2.31 [95% CI 1.06-5.01]) and cancer mortality (rate: sHR 2.36 [95% CI 1.11-5.01]; percent: sHR 1.90 [95% CI 1.00-3.62]). Overweight BMI was protective of cardiovascular mortality (sHR 0.59 [95% CI 0.38-0.91]), while underweight BMI was associated with a near 3-fold increased risk of respiratory mortality (sHR 2.93 [95% CI 1.28-6.67]). Incorporation of time-varying BMI and weight loss in the same models did not substantially alter individual associations for cardiovascular and cancer mortality, but an association between weight-loss percentage and respiratory mortality was attenuated after BMI adjustment. CONCLUSION: Both BMI and weight loss are predictors of cause-specific mortality in RA. Weight loss is a strong predictor of cardiovascular and cancer mortality, while underweight BMI is a stronger predictor of respiratory mortality.

Associations of Circulating Cytokines and Chemokines With Cancer Mortality in Men With Rheumatoid Arthritis.

OBJECTIVE: To examine the potential of circulating cytokines and chemokines as biomarkers of cancer mortality risk in patients with rheumatoid arthritis (RA). METHODS: Male participants in the Veterans Affairs RA registry were followed up from the time of enrollment until death or December 2013. Cytokines and chemokines were measured in banked serum obtained at the time of enrollment, using a bead-based multiplex assay, and a previously developed cytokine score was calculated. Vital status and cause of death were determined through the National Death Index. Associations of cytokines with cancer mortality were examined using multivariable competing-risks regression. RESULTS: Among 1,190 men with RA, 60 cancer deaths (30 of which were attributable to lung cancer) occurred over 5,307 patient-years of follow-up. The patients had a mean age of 64.5 years, had established disease (median duration 8.7 years), were seropositive for rheumatoid factor (81%) or anti-cyclic citrullinated peptide antibody (77%), and frequently had a history of smoking (82% current or former). Seven of 17 analytes examined were individually associated with cancer mortality. The cytokine score was associated with overall cancer (subhazard ratio [SHR] 1.42, 95% confidence interval [95% CI] 1.08-1.85) and lung cancer (SHR 1.86, 95% CI 1.57-2.19) mortality in multivariable analyses. Those in the highest quartile of cytokine scores had a >2-fold increased risk of overall cancer mortality (P = 0.039) and a 6-fold increased risk of lung cancer mortality (P = 0.028) relative to the lowest quartile. A synergistic interaction between current smoking and high cytokine score was observed. CONCLUSION: Serum cytokines and chemokines are associated with cancer and lung cancer mortality in men with RA, independent of multiple factors including age, smoking status, and prevalent cancer.

Cause-Specific Mortality in Male US Veterans With Rheumatoid Arthritis.

OBJECTIVE: There has been limited investigation into cause-specific mortality and the associated risk factors in men with rheumatoid arthritis (RA). We investigated all-cause and cause-specific mortality in men with RA, examining determinants of survival. METHODS: Men from a longitudinal RA registry were followed from enrollment until death or through 2013. Vital status and cause of death were determined using the National Death Index. Crude mortality rates and standardized mortality ratios (SMRs) were calculated for all-cause, cardiovascular disease (CVD), cancer, and respiratory mortality. Associations with all-cause and cause-specific mortality were examined using multivariable Cox proportional hazards and competing-risks regression. RESULTS: There were 1,652 men with RA and 332 deaths. The leading causes of death were CVD (31.6%; SMR 1.77 [95% confidence interval (95% CI) 1.46-2.14]), cancer (22.9%; SMR 1.50 [95% CI 1.20-1.89]), and respiratory disease (15.1%; SMR 2.90 [95% CI 2.20-3.83]). Factors associated with all-cause mortality included older age, white race, smoking, low body weight, comorbidity, disease activity, and prednisone use. Rheumatoid factor concentration and nodules were associated with CVD mortality. There were no associations of methotrexate or biologic agent use with all-cause or cause-specific mortality. CONCLUSION: Men in this RA cohort experienced increased all-cause and cause-specific mortality, with a 3-fold risk of respiratory-related deaths compared to age-matched men in the general population. Further studies are needed in order to examine whether interventions targeting potentially modifiable correlates of mortality might lead to improved long-term survival in men with RA.

Vascular calcifications on hand radiographs in rheumatoid arthritis and associations with autoantibodies, cardiovascular risk factors and mortality.

OBJECTIVE: To examine whether vascular calcifications on hand films in RA might aid in determining mortality risk. METHODS: Hand radiographs from 906 RA patients were scored as positive or negative for vascular calcifications. Patient characteristics associated with vascular calcifications were assessed using multivariable logistic regression, and associations with mortality were examined using Cox proportional hazards regression. Cytokines and multiplex ACPA were measured in both groups. RESULTS: A total of 99 patients (11%) demonstrated radiographic vascular calcifications. Factors independently associated with vascular calcifications included diabetes [odds ratio (OR) 2.85; 95% CI 1.43, 5.66], cardiovascular disease at enrolment (OR 2.48; 95% CI 1.01, 6.09), prednisone use (OR 1.90; 95% CI 1.25, 2.91), current smoking (OR 0.06; 95% CI 0.01, 0.23) and former smoking (OR 0.36; 95% CI 0.27, 0.48) vs never smoking. In cytokine and ACPA subtype analysis, IL-4 and anti-citrullinated apolipoprotein E were significantly increased in patients with vascular calcifications in fully adjusted multivariable models. After multivariable adjustment, vascular calcifications were associated with an increase in all-cause mortality (hazard ratio 1.41; 95% CI 1.12, 1.78; P = 0.004). CONCLUSION: Vascular calcifications on hand radiographs were independently associated with increased all-cause mortality in RA. Mechanisms underpinning the associations of IL-4 and select ACPA with vascular calcifications and their utility as biomarkers predictive of cardiovascular disease risk in RA merit further study.

Alveolar bone loss is associated with circulating anti-citrullinated protein antibody (ACPA) in patients with rheumatoid arthritis.

BACKGROUND: This study examines: 1) alveolar bone loss (ABL), a hallmark of periodontitis, in anti-citrullinated protein antibody (ACPA)-positive rheumatoid arthritis (RA) patients versus control patients with osteoarthritis (OA); and 2) the association of ABL with RA disease activity and ACPA concentrations, including multiple antigen-specific ACPA. METHODS: This multicenter case-control study includes 617 patients diagnosed with RA (n = 287) or OA (n = 330). Panoramic radiographs were taken; patients were categorized into low, moderate, or high tertiles based on mean percentage ABL. Serum ACPA was measured using second-generation anticyclic citrullinated peptide enzyme-linked immunosorbent assay and a multiplex platform to assess distinct antigen-specific ACPA. A generalized linear mixed model for binary data was used to compare stratified ABL in RA versus OA patients. Associations of moderate and high ABL (versus low) with RA disease activity and severity measures were examined using multivariate regression. Antigen-specific ACPA responses were compared among ABL tertiles using significance analysis of microarrays. RESULTS: ACPA-positive patients with RA had a significantly higher mean percentage of sites with ABL >20% compared with patients with OA (P = 0.03). After multivariate adjustment, greater ABL was significantly associated with higher serum ACPA concentration (P = 0.004), 28-joint Disease Activity Score (P = 0.023), health assessment questionnaire disability (P = 0.05), tender joint count (P = 0.02) and joint space narrowing scores (P = 0.05) among patients with RA. ACPAs targeting citrullinated vimentin and histone were significantly higher in moderate and high ABL groups versus low, regardless of smoking status (q <0.1%). CONCLUSIONS: Greater ABL was associated with higher ACPA, consistent with findings at articular sites. ACPA targeting could provide novel insight into important linkages between RA and periodontitis.

Periodontitis and Porphyromonas gingivalis in patients with rheumatoid arthritis.

OBJECTIVE: To examine the degree to which shared risk factors explain the relationship of periodontitis (PD) to rheumatoid arthritis (RA) and to determine the associations of PD and Porphyromonas gingivalis with pathologic and clinical features of RA. METHODS: Patients with RA (n = 287) and patients with osteoarthritis as disease controls (n = 330) underwent a standardized periodontal examination. The HLA-DRB1 status of all participants was imputed using single-nucleotide polymorphisms from the extended major histocompatibility complex. Circulating anti-P gingivalis antibodies were measured using an enzyme-linked immunosorbent assay, and subgingival plaque was assessed for the presence of P gingivalis using polymerase chain reaction (PCR). Associations of PD with RA were examined using multivariable regression. RESULTS: Presence of PD was more common in patients with RA and patients with anti-citrullinated protein antibody (ACPA)-positive RA (n = 240; determined using the anti-cyclic citrullinated peptide 2 [anti-CCP-2] test) than in controls (35% and 37%, respectively, versus 26%; P = 0.022 and P = 0.006, respectively). There were no differences between RA patients and controls in the levels of anti-P gingivalis or the frequency of P gingivalis positivity by PCR. The anti-P gingivalis findings showed a weak, but statistically significant, association with the findings for both anti-CCP-2 (r = 0.14, P = 0.022) and rheumatoid factor (RF) (r = 0.19, P = 0.001). Presence of PD was associated with increased swollen joint counts (P = 0.004), greater disease activity according to the 28-joint Disease Activity Score using C-reactive protein level (P = 0.045), and higher total Sharp scores of radiographic damage (P = 0.015), as well as with the presence and levels of anti-CCP-2 (P = 0.011) and RF (P < 0.001). The expression levels of select ACPAs (including antibodies to citrullinated filaggrin) were higher in patients with subgingival P gingivalis and in those with higher levels of anti-P gingivalis antibodies, irrespective of smoking status. Associations of PD with established seropositive RA were independent of all covariates examined, including evidence of P gingivalis infection. CONCLUSION: Both PD and P gingivalis appear to shape the autoreactivity of RA. In addition, these results demonstrate an independent relationship between PD and established seropositive RA.

Association of rheumatoid arthritis susceptibility gene with lipid profiles in patients with rheumatoid arthritis.

OBJECTIVE: RA patients have an increased risk of cardiovascular (CV) disease, although the mechanisms are unclear. As RA and CV disease may be associated through lipid profiles, we examined whether single nucleotide polymorphisms (SNPs) associated with RA susceptibility were associated with low-density lipoprotein (LDL), high-density lipoprotein (HDL) and triglyceride (TG) levels in RA subjects. METHODS: Patients (n = 763) enrolled in the Veterans Affairs RA registry who were not on hydroxymethylglutaryl-CoA reductase inhibitor were genotyped for human leukocyte antigen shared epitope (HLA-DRB1-SE) and SNPs in the following genes: CTLA-4 (cytotoxic T-lymphocyte antigen 4), IL-10, PTPN22 (protein tyrosine phosphatase, non-receptor type 22), REL (c-Rel), STAT4 (signal transducer and activator of transcription protein), TNF- and TRAF1 (TNF receptor-associated factor 1). Other covariates included patient characteristics (age, gender, race, smoking status, education, BMI, modified CharlsonDeyo comorbidity index), CV characteristics (hypertension, diabetes, alcohol abuse), pharmacologic exposures (MTX, anti-TNF, glucocorticoids) and RA severity/activity markers (RA disease duration, mean DAS, CRP, RF positivity, anti-CCP positivity). Multivariate linear regression was performed to determine the factors associated with LDL, HDL and TG levels. RESULTS: The REL SNP rs9309331 homozygous minor allele was associated with higher LDL levels. Caucasian race and increasing BMI were associated with lower HDL. Factors associated with higher TG were diabetes, Caucasian race and higher BMI. CONCLUSION: The REL SNP rs9309331 was associated with LDL levels in our study. This association is a possible explanation of the increased risk of RA patients for CV disease and requires further inquiry.

Cardiovascular events are not associated with MTHFR polymorphisms, but are associated with methotrexate use and traditional risk factors in US veterans with rheumatoid arthritis.

OBJECTIVE: C677T and A1298C polymorphisms in the enzyme methylenetetrahydrofolate reductase (MTHFR) have been associated with increased cardiovascular (CV) events in non-rheumatoid arthritis (RA) populations. We investigated potential associations of MTHFR polymorphisms and use of methotrexate (MTX) with time-to-CV event in data from the Veterans Affairs Rheumatoid Arthritis (VARA) registry. METHODS: VARA participants were genotyped for MTHFR polymorphisms. Variables included demographic information, baseline comorbidities, RA duration, autoantibody status, and disease activity. Patients' comorbidities and outcome variables were defined using International Classification of Diseases-9 and Current Procedural Terminology codes. The combined CV event outcome included myocardial infarction (MI), percutaneous coronary intervention, coronary artery bypass graft surgery, and stroke. Cox proportional hazards regression was used to model the time-to-CV event. RESULTS: Data were available for 1047 subjects. Post-enrollment CV events occurred in 97 patients (9.26%). Although there was a trend toward reduced risk of CV events, MTHFR polymorphisms were not significantly associated with time-to-CV event. Time-to-CV event was associated with prior stroke (HR 2.01, 95% CI 1.03-3.90), prior MI (HR 1.70, 95% CI 1.06-2.71), hyperlipidemia (HR 1.57, 95% CI 1.01-2.43), and increased modified Charlson-Deyo index (HR 1.23, 95% CI 1.13-1.34). MTX use (HR 0.66, 95% CI 0.44-0.99) and increasing education (HR 0.87, 95% CI 0.80-0.95) were associated with a lower risk for CV events. CONCLUSION: Although MTHFR polymorphisms were previously associated with CV events in non-RA populations, we found only a trend toward decreased association with CV events in RA. Traditional risk factors conferred substantial CV risk, while MTX use and increasing years of education were protective.