CONQUER Scleroderma: association of gastrointestinal tract symptoms in early disease with resource utilization.

OBJECTIVES: SSc is associated with increased health-care resource utilization and economic burden. The Collaborative National Quality and Efficacy Registry (CONQUER) is a US-based collaborative that collects longitudinal follow-up data on SSc patients with <5 years of disease duration enrolled at scleroderma centres in the USA. The objective of this study was to investigate the relationship between gastrointestinal tract symptoms and self-reported resource utilization in CONQUER participants. METHODS: CONQUER participants who had completed a baseline and 12-month Gastrointestinal Tract Questionnaire (GIT 2.0) and a Resource Utilization Questionnaire (RUQ) were included in this analysis. Patients were categorized by total GIT 2.0 severity: none-to-mild (0-0.49); moderate (0.50-1.00), and severe-to-very severe (1.01-3.00). Clinical features and medication exposures were examined in each of these categories. The 12-month RUQ responses were summarized by GIT 2.0 score categories at 12 months. RESULTS: Among the 211 CONQUER participants who met the inclusion criteria, most (64%) had mild GIT symptoms, 26% had moderate symptoms, and 10% severe GIT symptoms at 12 months. The categorization of GIT total severity score by RUQ showed that more upper endoscopy procedures and inpatient hospitalization occurred in the CONQUER participants with severe GIT symptoms. These patients with severe GIT symptoms also reported the use of more adaptive equipment. CONCLUSION: This report from the CONQUER cohort suggests that severe GIT symptoms result in more resource utilization. It is especially important to understand resource utilization in early disease cohorts when disease activity, rather than damage, primarily contributes to health-related costs of SSc.

Safety and Efficacy of B-Cell Depletion with Rituximab for the Treatment of Systemic Sclerosis-associated Pulmonary Arterial Hypertension: A Multicenter, Double-Blind, Randomized, Placebo-controlled Trial.

Rationale: Systemic sclerosis (SSc)-pulmonary arterial hypertension (PAH) is one of the most prevalent and deadly forms of PAH. B cells may contribute to SSc pathogenesis. Objectives: We investigated the safety and efficacy of B-cell depletion for SSc-PAH. Methods: In an NIH-sponsored, multicenter, double-blinded, randomized, placebo-controlled, proof-of-concept trial, 57 patients with SSc-PAH on stable-dose standard medical therapy received two infusions of 1,000 mg rituximab or placebo administered 2 weeks apart. The primary outcome measure was the change in 6-minute-walk distance (6MWD) at 24 weeks. Secondary endpoints included safety and invasive hemodynamics. We applied a machine learning approach to predict drug responsiveness. Measurements and Main Results: We randomized 57 subjects from 2010 to 2018. In the primary analysis, using data through Week 24, the adjusted mean change in 6MWD at 24 weeks favored the treatment arm but did not reach statistical significance (23.6 ± 11.1 m vs. 0.5 ± 9.7 m; P = 0.12). Although a negative study, when data through Week 48 were also considered, the estimated change in 6MWD at Week 24 was 25.5 ± 8.8 m for rituximab and 0.4 ± 7.4 m for placebo (P = 0.03). Rituximab treatment appeared to be safe and well tolerated. Low levels of RF (rheumatoid factor), IL-12, and IL-17 were sensitive and specific as favorable predictors of a rituximab response as measured by an improved 6MWD (receiver operating characteristic area under the curve, 0.88-0.95). Conclusions: B-cell depletion therapy is a potentially effective and safe adjuvant treatment for SSc-PAH. Future studies in these patients can confirm whether the identified biomarkers predict rituximab responsiveness. Clinical trial registered with www.clinicaltrails.gov (NCT01086540).

CD4+ Group 1 Innate Lymphoid Cells (ILC) Form a Functionally Distinct ILC Subset That Is Increased in Systemic Sclerosis.

Innate lymphoid cells (ILC) are a heterogeneous group of cellular subsets that produce large amounts of T cell-associated cytokines in response to innate stimulation in the absence of Ag. In this study, we define distinct patterns of surface marker and cytokine expression among the ILC subsets that may further delineate their migration and function. Most notably, we found that the subset previously defined as group 1 ILC (ILC1) contains CD4(+) CD8(-), CD4(-) CD8(+), and CD4(-) CD8(-) populations. Although all ILC1 subsets shared characteristics with Th1 cells, CD4(+) ILC1 also demonstrated significant phenotypic and functional heterogeneity. We also show that the frequencies of CD4(+) ILC1 and NKp44(+) group 3 ILC, but not CD4(-) ILC1 or group 2 ILC, are increased in the peripheral blood of individuals with systemic sclerosis (SSc), a disease characterized by fibrotic and vascular pathology, as well as immune dysregulation. Furthermore, we demonstrate that CD4(+) and CD4(-) ILC1 are functionally divergent based on their IL-6Rα expression and that the frequency of IL-6Rα expression on ILC is altered in SSc. The distinct phenotypic and functional features of CD4(+) and CD4(-) ILC1 suggest that they may have differing roles in the pathogenesis of immune-mediated diseases, such as SSc.

Utility of B-type natriuretic peptides in the assessment of patients with systemic sclerosis-associated pulmonary hypertension in the PHAROS registry.

OBJECTIVES: To assess the utility of B-type natriuretic peptide (BNP) and N-terminal pro-BNP (NT-proBNP) in detecting and monitoring pulmonary hypertension (PH) in systemic sclerosis (SSc). METHODS: PHAROS is a multicenter prospective cohort of SSc patients at high risk for developing pulmonary arterial hypertension (SSc-AR-PAH) or with a definitive diagnosis of SSc-PH. We evaluated 1) the sensitivity and specificity of BNP≥64 and NT-proBNP≥210 pg/mL for the detection of SSc-PAH and/ or SSc-PH in the SSc-AR-PAH population; 2) baseline and longitudinal BNP and NT-proBNP levels as predictors of progression to SSc-PAH and/or SSc-PH; 3) baseline BNP≥180, NT-proBNP≥553 pg/mL, and longitudinal changes in BNP and NT-proBNP as predictors of mortality in SSc-PH diagnosed patients. RESULTS: 172 SSc-PH and 157 SSc-AR- PAH patients had natriuretic peptide levels available. Median BNP and NT-proBNP were significantly higher in the SSc-PH versus SSc-AR-PAH group. The sensitivity and specificity for SSc-PAH detection using baseline BNP≥64 pg/mL was 71% and 59%; and for NT-proBNP≥210 pg/mL, 73% and 78%. NT-proBNP showed stronger correlations with haemodynamic indicators of right ventricular dysfunction than BNP. Baseline creatinine, RVSP > 40 mmHg, and FVC%:DLco% ratio ≥1.8 were associated with progression from SSc-AR-PAH to SSc-PH but no association with individual or combined baseline BNP and NT-proBNP levels was observed. Baseline and follow-up BNP or NT-proBNP levels were not predictive of death, however, a composite BNP/NT-proBNP group predicted mortality (HR 3.81 (2.08-6.99), p<.0001). CONCLUSIONS: NT-proBNP may be more useful than BNP in the detection and monitoring of PAH in SSc patients, but additional studies are necessary.

An Experimental Phototherapy Device for Studying the Effects of Blue Light on Patients with Raynaud's Phenomenon.

Raynaud's phenomenon (RP) is a condition that causes decreased blood flow to areas perfused by small blood vessels (e.g., fingers, toes). In severe cases, ulceration, gangrene, and loss of fingers may occur. Most treatments focus on inducing vasorelaxation in affected areas by the way of pharmaceuticals. Recently, animal studies have shown that vasorelaxation can be induced by non-coherent blue light (wavelength ~ 430-460 nm) through the actions of melanopsin, a photoreceptive opsin protein encoded by the OPN4 gene. To study this effect in humans, a reliable phototherapy device (PTD) is needed. We outline the construction of a PTD to be used in studying blue light effects on Raynaud's patients. Our design addresses user safety, calibration, electromagnetic compatibility/interference (EMC/EMI), and techniques for measuring physiological responses (temperature sensors, laser Doppler flow sensors, infrared thermal imaging of the hands). We tested our device to ensure (1) safe operating conditions, (2) predictable, user-controlled irradiance output levels, (3) an ability for measuring physiological responses, and (4) features necessary to enable a double-blinded crossover study for a clinical trial. We also include in the Methods an approved research protocol utilizing our device that may serve as a starting point for clinical study. We introduced a reliable PTD for studying the effects of blue light therapy for patients suffering from Raynaud's phenomenon and showed that our device is safe and reliable and includes the required measurement vectors for tracking treatment effects throughout the duration of a clinical study.

The primary cardiomyopathy of systemic sclerosis on cardiovascular magnetic resonance imaging.

AIMS: Cardiac disease in systemic sclerosis (SSc) may be primary or secondary to other disease manifestations of SSc. The prevalence of the primary cardiomyopathy of SSc is unknown. Cardiovascular magnetic resonance (CMR) imaging can help accurately determine the presence and cause of cardiomyopathy. We aimed to investigate the prevalence, the CMR features, and the prognostic implications of the primary cardiomyopathy of SSc. METHODS AND RESULTS: We conducted a retrospective cohort study of consecutive patients with SSc who had a clinical CMR for suspected cardiac involvement. We identified the prevalence, the CMR features of the primary cardiomyopathy of SSc, and its association with the long-term incidence of death or major adverse cardiac events (MACEs): heart failure hospitalization, ventricular assist device implantation, heart transplantation, and sustained ventricular tachycardia. Of 130 patients with SSc, 80% were women, and the median age was 58 years. On CMR, 22% had an abnormal left ventricular ejection fraction, and 40% had late gadolinium enhancement (LGE). The prevalence of the primary cardiomyopathy of SSc was 21%. A third of these patients had a distinct LGE phenotype. Over a median follow-up of 3.6 years after the CMR, patients with the primary cardiomyopathy of SSc had a greater incidence of death or MACE (adjusted hazard ratio 2.01; 95% confidence interval 1.03-3.92; P = 0.041). CONCLUSION: The prevalence of the primary cardiomyopathy of SSc was 21%, with a third demonstrating a distinct LGE phenotype. The primary cardiomyopathy of SSc was independently associated with a greater long-term incidence of death or MACE.

Qualitative Interviews to Assess the Content Validity and Usability of the Electronic Raynaud Diary in Patients with Systemic Sclerosis.

OBJECTIVE: To better understand the symptoms and impacts of Raynaud phenomenon (RP) in patients with systemic sclerosis (SSc) and to evaluate the content validity and usability of a new electronic patient-reported outcome (PRO) measure for RP: the Raynaud Diary. METHODS: The Raynaud Diary was developed as a daily eDiary for assessing the number and duration of symptomatic Raynaud attacks; worst pain, numbness, tingling, and discomfort in the fingers; and overall disease severity, captured using the Raynaud's Condition Score. The Raynaud Diary was debriefed in two waves of qualitative interviews with adults with self-reported RP secondary to SSc. All interviews included open-ended questions about participants' experiences of RP. RESULTS: Participants (N = 39) had a mean age of 55.1 years, and 87% were female. Frequently reported RP symptoms were color change (reported by all participants), numbness (90%), tingling (82%), pain (77%), and discomfort (72%). Common attack triggers included temperature-related factors and stress. Participants reported being unable to be outside or do outdoor activities and had problems gripping objects. All participants demonstrated understanding of the Raynaud Diary instructions. Most participants indicated that they would be able to use the Raynaud Diary to record the worst severity of individual RP symptoms in the previous 24 hours. CONCLUSION: Patients with RP secondary to SSc bear a heavy symptom burden. The Raynaud Diary is a content valid PRO measure that captures the most frequent symptoms of RP in patients with SSc.

Castleman disease and associated autoimmune disease.

PURPOSE OF REVIEW: Castleman disease can occur in association with autoimmune connective tissue disease and confound the clinical picture, resulting in delayed diagnosis and suboptimal treatment. This review focuses on the intersection of Castleman disease and autoimmunity with an emphasis on shared pathology and mutually beneficial treatments. RECENT FINDINGS: Targeting CD-20, interleukin-6, and the nuclear factor-κB pathway has shown promise in achieving long-term remission in patients with Castleman disease and associated autoimmune features. SUMMARY: Advances in understanding of pathogenic cell types and cytokines in Castleman disease have allowed the development of targeted therapies successful in the treatment of both Castleman disease and associated autoimmune disease.

Positive selection optimizes the number and function of MHCII-restricted CD4+ T cell clones in the naive polyclonal repertoire.

T cell receptors (TCRs) on T lymphocytes in an individual bind foreign peptides bound to major histocompatibility complex (MHC) molecules expressed in that individual (designated MHC(A)). Results from radiation bone marrow chimeras and TCR transgenic mice indicate that this complex form of antigen recognition is the result of positive selection of clones with low affinity for self peptide:MHC(A) complexes during development. Here we used a sensitive peptide:MHC tetramer enrichment method to quantify the role of positive selection in the generation of the preimmune polyclonal T cell repertoire in normal individuals. We made the surprising observation that mouse and human naive T cells capable of binding to foreign peptide:MHC(A) were present at the same frequency in hosts that expressed MHC(A) or a different MHC isoform (MHC(B)). However, most of the clones in MHC(B) hosts also recognized self peptide:MHC(A) complexes. When these "alloreactive" T cells were removed from the MHC(B) repertoire via negative selection in an MHC(A) host, the number of foreign peptide:MHC(A)-binding T cells was reduced to one fifth and many of the remaining cells did not respond to the peptide. Therefore, although positive selection on MHC(A) was not required to produce foreign peptide:MHC(A)-binding clones, it had a large effect on selecting responsive clones.

Periodontal disease, tooth loss and incident rheumatoid arthritis: results from the First National Health and Nutrition Examination Survey and its epidemiological follow-up study.

AIMS: Infection may be a rheumatoid arthritis (RA) risk factor. We examined whether signs of periodontal infection were associated with RA development in the First National Health and Nutrition Examination Survey and its epidemiological follow-up study. MATERIAL AND METHODS: In 1971-1974, 9702 men and women aged 25-74 were enrolled and surveyed longitudinally (1982, 1986, 1987, 1992). Periodontal infection was defined by baseline tooth loss or clinical evidence of periodontal disease. Baseline (n = 138) and incident (n = 433) RA cases were defined via self-report physician diagnosis, joint pain/swelling, ICD-9 codes (714.0-714.9), death certificates and/or RA hospitalization. RESULTS: Adjusted odds ratios (ORs) (95% CI) for prevalent RA in gingivitis and periodontitis (versus healthy) were 1.09 (0.57, 2.10) and 1.85 (0.95, 3.63); incident RA ORs were 1.32 (0.85, 2.06) and 1.00 (0.68, 1.48). The ORs for prevalent RA among participants missing 5-8, 9-14, 15-31 or 32 teeth (versus 0-4 teeth) were 1.74 (1.03, 2.95), 1.82 (0.81, 4.10), 1.45 (0.62, 3.41) and 1.30 (0.48, 3.53); ORs for incident RA were 1.12 (0.77, 1.64), 1.67 (1.12, 2.48), 1.40 (0.85, 2.33) and 1.22 (0.75, 2.00). Dose-responsiveness was enhanced among never smokers. The rate of death or loss-to-follow-up after 1982 was two- to fourfold higher among participants with periodontitis or missing ≥9 teeth (versus healthy participants). CONCLUSIONS: Although participants with periodontal disease or ≥5 missing teeth experienced higher odds of prevalent/incident RA, most ORs were non-statistically significant and lacked dose-responsiveness. Differential RA ascertainment bias complicated the interpretation of these data.

A Fatal Case of Diffuse Alveolar Hemorrhage in the Setting of Systemic Lupus Erythematosus: A Case Report and Review of Noninfectious Causes of Acute Pulmonary Hemorrhage in Adults.

Systemic lupus erythematosus (SLE) is an autoimmune connective tissue disease, characterized by autoantibody production and immune complex formation, that has the potential to affect virtually any organ. Pleuropulmonary involvement occurs in 50-70% and commonly manifests as pleuritis and pleural effusion. Diffuse alveolar hemorrhage (DAH) is a rare manifestation of SLE. Most cases of DAH occur in young adults with an underlying autoimmune disease such as systemic vasculitis or Goodpasture syndrome. SLE is typically lower on the list of initial differential diagnoses of DAH due to its rarity compared to other etiologies. We present a case of a patient with dyspnea on exertion, dry coughs, lower extremity edema, and intermittent periorbital edema who ultimately succumbed to respiratory failure secondary to DAH in the setting of SLE. The diagnosis of SLE was suspected clinically and confirmed at autopsy due to her rapid clinical deterioration. DAH requires prompt intervention, and management is guided by the underlying disease process. SLE is a potentially treatable disease; therefore, timely diagnosis is important in order to exclude other noninfectious causes of DAH (reviewed in this report) and to initiate appropriate therapy.

Safety and efficacy of abatacept in early diffuse cutaneous systemic sclerosis (ASSET): open-label extension of a phase 2, double-blind randomised trial.

BACKGROUND: Abatacept was well tolerated by patients with early diffuse cutaneous systemic sclerosis in a phase 2, double-blind randomised trial, with potential efficacy at 12 months. We report here the results of an open-label extension for 6 months. METHODS: Patients (aged ≥18 years) with diffuse cutaneous systemic sclerosis of less than 3 years' duration from their first non-Raynaud's symptom were enrolled into the ASSET trial (A Study of Subcutaneous Abatacept to Treat DiffuseCutaneous Systemic Sclerosis), which is a double-blind trial at 22 sites in Canada, the UK, and the USA. Aftercompletion of 12 months of treatment with either abatacept or placebo, patients received a further 6 months ofabatacept (125 mg subcutaneous every week) in an open-label extension. The primary endpoint of the double-blind trial was modified Rodnan Skin Score (mRSS) at 12 months, which was reassessed at 18 months in the open-label extension. The primary analysis included all participants who completed the double-blind trial and received at least one dose of open-label treatment (modified intention to treat). This trial is registered with ClinicalTrials.gov, NCT02161406. FINDINGS: Between Sept 22, 2014, and March 15, 2017, 88 participants were randomly allocated in the double-blind trial either abatacept (n=44) or placebo (44); 32 patients from each treatment group completed the 6-month open-labelextension. Among patients assigned abatacept, a mean improvement from baseline in mRSS was noted at 12 months (-6·6 [SD 6·4]), with further improvement seen during the open-label extension period (-9·8 [8·1] at month 18). Participants assigned placebo had a mean improvement from baseline in mRSS at 12 months (-3·7 [SD 7·6]), with a further improvement at month 18 (-6·3 [9·3]). Infections during the open-label extension phase occurred in nine patients in the placebo-abatacept group (12 adverse events, one serious adverse event) and in 11 patients in theabatacept-abatacept group (14 adverse events, one serious adverse event). Two deaths occurred during the 12-month double-blind period in the abatacept group, which were related to scleroderma renal crisis; no deaths were recorded during the open-label extension. INTERPRETATION: During the 6-month open-label extension, no new safety signals for abatacept were identified in the treatment of diffuse cutaneous systemic sclerosis. Clinically meaningful improvements in mRSS and other outcome measures were observed in both the abatacept and placebo groups when patients transitioned to open-label treatment. These data support further studies of abatacept in diffuse cutaneous systemic sclerosis. FUNDING: Bristol-Myers Squibb and National Institutes of Health.

Glucosamine, chondroitin sulfate, and the two in combination for painful knee osteoarthritis.

BACKGROUND: Glucosamine and chondroitin sulfate are used to treat osteoarthritis. The multicenter, double-blind, placebo- and celecoxib-controlled Glucosamine/chondroitin Arthritis Intervention Trial (GAIT) evaluated their efficacy and safety as a treatment for knee pain from osteoarthritis. METHODS: We randomly assigned 1583 patients with symptomatic knee osteoarthritis to receive 1500 mg of glucosamine daily, 1200 mg of chondroitin sulfate daily, both glucosamine and chondroitin sulfate, 200 mg of celecoxib daily, or placebo for 24 weeks. Up to 4000 mg of acetaminophen daily was allowed as rescue analgesia. Assignment was stratified according to the severity of knee pain (mild [N=1229] vs. moderate to severe [N=354]). The primary outcome measure was a 20 percent decrease in knee pain from baseline to week 24. RESULTS: The mean age of the patients was 59 years, and 64 percent were women. Overall, glucosamine and chondroitin sulfate were not significantly better than placebo in reducing knee pain by 20 percent. As compared with the rate of response to placebo (60.1 percent), the rate of response to glucosamine was 3.9 percentage points higher (P=0.30), the rate of response to chondroitin sulfate was 5.3 percentage points higher (P=0.17), and the rate of response to combined treatment was 6.5 percentage points higher (P=0.09). The rate of response in the celecoxib control group was 10.0 percentage points higher than that in the placebo control group (P=0.008). For patients with moderate-to-severe pain at baseline, the rate of response was significantly higher with combined therapy than with placebo (79.2 percent vs. 54.3 percent, P=0.002). Adverse events were mild, infrequent, and evenly distributed among the groups. CONCLUSIONS: Glucosamine and chondroitin sulfate alone or in combination did not reduce pain effectively in the overall group of patients with osteoarthritis of the knee. Exploratory analyses suggest that the combination of glucosamine and chondroitin sulfate may be effective in the subgroup of patients with moderate-to-severe knee pain. (ClinicalTrials.gov number, NCT00032890.).

Toward the early diagnosis of systemic sclerosis: warning signs the practitioner needs to recognize.

Systemic sclerosis, or scleroderma, is a rare condition that first presents with symptoms common to many other diseases. Because of this, diagnosing it can be difficult and take time.This article describes warning signs of possible incipient scleroderma as well as tests that can help the primary care provider identify this serious autoimmune disorder.

Risk Factors for Mortality and Cardiopulmonary Hospitalization in Systemic Sclerosis Patients At Risk for Pulmonary Hypertension, in the PHAROS Registry.

OBJECTIVE: We sought to identify predictors of mortality and cardiopulmonary hospitalizations in patients at risk for pulmonary hypertension (PH) and enrolled in PHAROS, a prospective cohort study to investigate the natural history of PH in systemic sclerosis (SSc). METHODS: The at-risk population for PH was defined by the following entry criteria: echocardiogram systolic pulmonary arterial pressure > 40 mmHg, or DLCO < 55% predicted or ratio of % forced vital capacity/%DLCO > 1.6, measured by pulmonary function testing. Baseline clinical measures were evaluated as predictors of hospitalization and death between 2005 and 2014. Cox proportional hazards models were censored at date of PH onset or latest study visit and adjusted for age, sex, race, and disease duration. RESULTS: Of the 236 at-risk subjects who were followed for a median of 4 years (range 0.4-8.5 yrs), 35 developed PH after entering PHAROS (reclassified as PH group). In the at-risk group, higher mortality was strongly associated with male sex, low %DLCO, exercise oxygen desaturation, anemia, abnormal dyspnea scores, and baseline pericardial effusion. Risks for cardiopulmonary hospitalization were associated with increased dyspnea and pericardial effusions, although PH patients with DLCO < 50% had the highest risk of cardiopulmonary hospitalizations. CONCLUSION: Risk factors for poor outcome in patients with SSc who are at risk for PH were similar to others with SSc-PH and SSc-pulmonary arterial hypertension, including male sex, DLCO < 50%, exercise oxygen desaturation, and pericardial effusions. This group should undergo right heart catheterization and receive appropriate intervention if PH is confirmed.

Effect of mycophenolate mofetil on pulmonary function in scleroderma-associated interstitial lung disease.

OBJECTIVE: We sought to determine the effectiveness of mycophenolate mofetil (MMF) in scleroderma- associated interstitial lung disease (SSc-ILD). METHODS: We retrospectively identified patients who met criteria for systemic sclerosis, had evidence of SSc-ILD on chest CT, received > 1 g/d of MMF for >or= 6 months, and had pulmonary function data available. Vital capacity (VC) and diffusion capacity of the lung for carbon monoxide (Dlco) at treatment onset were compared with VC and Dlco values 12 months before and 12 months after treatment onset. Twelve-month values were imputed from regression lines generated using all VC and Dlco measurements made in the 24-month period either prior to or following treatment onset. RESULTS: Among 13 patients who met inclusion criteria, MMF was associated with a significant improvement in VC (mean, + 159 mL; confidence interval [CI], + 30 to + 289 mL; and + 4% of the predicted normal value; CI, + 2 to + 7%) after 12 months of treatment. In contrast, patients had a significant decrease in VC (mean, - 239 mL; CI, - 477 to - 0.5 mL; and - 5% of the predicted normal value; CI, - 11 to - 0.3%) in the 12 months prior to MMF treatment. Dlco did not change significantly during MMF treatment (mean, + 1% of the predicted normal value; CI, - 2 to + 5%) but decreased significantly in the 12 months prior to treatment (mean, - 5% of the predicted normal value; CI, - 10 to - 1%). CONCLUSION: These retrospective data suggest MMF improves VC in patients with SSc-ILD.

Gene-level association analysis of systemic sclerosis: A comparison of African-Americans and White populations.

Gene-level analysis of ImmunoChip or genome-wide association studies (GWAS) data has not been previously reported for systemic sclerosis (SSc, scleroderma). The objective of this study was to analyze genetic susceptibility loci in SSc at the gene level and to determine if the detected associations were shared in African-American and White populations, using data from ImmunoChip and GWAS genotyping studies. The White sample included 1833 cases and 3466 controls (956 cases and 2741 controls from the US and 877 cases and 725 controls from Spain) and the African American sample, 291 cases and 260 controls. In both Whites and African Americans, we performed a gene-level analysis that integrates association statistics in a gene possibly harboring multiple SNPs with weak effect on disease risk, using Versatile Gene-based Association Study (VEGAS) software. The SNP-level analysis was performed using PLINK v.1.07. We identified 4 novel candidate genes (STAT1, FCGR2C, NIPSNAP3B, and SCT) significantly associated and 4 genes (SERBP1, PINX1, TMEM175 and EXOC2) suggestively associated with SSc in the gene level analysis in White patients. As an exploratory analysis we compared the results on Whites with those from African Americans. Of previously established susceptibility genes identified in Whites, only TNFAIP3 was significant at the nominal level (p = 6.13x10-3) in African Americans in the gene-level analysis of the ImmunoChip data. Among the top suggestive novel genes identified in Whites based on the ImmunoChip data, FCGR2C and PINX1 were only nominally significant in African Americans (p = 0.016 and p = 0.028, respectively), while among the top novel genes identified in the gene-level analysis in African Americans, UNC5C (p = 5.57x10-4) and CLEC16A (p = 0.0463) were also nominally significant in Whites. We also present the gene-level analysis of SSc clinical and autoantibody phenotypes among Whites. Our findings need to be validated by independent studies, particularly due to the limited sample size of African Americans.

Association Between Serum Antibodies to Periodontal Bacteria and Rheumatoid Factor in the Third National Health and Nutrition Examination Survey.

OBJECTIVE: Alterations in the microbiome, including the periodontal microbiome, may be a risk factor for rheumatoid arthritis (RA). Most studies that have analyzed this association are relatively small, focus primarily on a single periodontal pathogen (Porphyromonas gingivalis), and are not population based. This study was undertaken to investigate the association between elevated serum levels of IgG antibodies to 19 periodontal species and the prevalence of rheumatoid factor (RF) in a large nationally representative sample of adults. METHODS: The Third National Health and Nutrition Examination Survey (NHANES-III) is a cross-sectional sample of the noninstitutionalized US population (n = 33,994). Our study population included all dentate participants who were 60 years and older, did not have RA as defined by a modified version of the American College of Rheumatology 1987 criteria, and had complete data for both serum IgG antibodies against periodontal bacteria and serum RF antibody titer (n = 2,461). RESULTS: Adjusted odds ratios (ORs) and 95% confidence intervals (95% CIs) summarizing the relationship between the 19 periodontal serum IgG antibodies and RF seropositivity ranged from 0.53 (95% CI 0.29-0.97) to 1.27 (95% CI 0.79-2.06), and 17 of the 19 observed ORs were <1.0. The ORs for RF seropositivity among participants with elevated Prevotella intermedia (0.53 [95% CI 0.29-0.97]) and Capnocytophaga ochracea (0.54 [0.31-0.95]) IgG levels were statistically significant. CONCLUSION: Our findings indicate that elevated levels of IgG antibodies to periodontal bacteria are mostly unassociated with RF seropositivity in the nationally representative NHANES-III. Elevated levels of antibodies to P intermedia and C ochracea are associated with lower odds of RF seropositivity.