Comprehensive analysis of the major histocompatibility complex in systemic sclerosis identifies differential HLA associations by clinical and serological subtypes

Autoantibodies; Genetic; PolymorphismAutoanticuerpos; Genética; PolimorfismoAutoanticossos; Genètica; PolimorfismeObjective The greatest genetic effect reported for systemic sclerosis (SSc) lies in the major histocompatibility complex (MHC) locus. Leveraging the largest SSc genome-wide association study, we aimed to fine-map this region to identify novel human leucocyte antigen (HLA) genetic variants associated with SSc susceptibility and its main clinical and serological subtypes. Methods 9095 patients with SSc and 17 584 controls genome-wide genotyped were used to impute and test single-nucleotide polymorphisms (SNPs) across the MHC, classical HLA alleles and their composite amino acid residues. Additionally, patients were stratified according to their clinical and serological status, namely, limited cutaneous systemic sclerosis (lcSSc), diffuse cutaneous systemic sclerosis (dcSSc), anticentromere (ACA), antitopoisomerase (ATA) and anti-RNApolIII autoantibodies (ARA). Results Sequential conditional analyses showed nine SNPs, nine classical alleles and seven amino acids that modelled the observed associations with SSc. This confirmed previously reported associations with HLA-DRB1*11:04 and HLA-DPB1*13:01, and revealed a novel association of HLA-B*08:01. Stratified analyses showed specific associations of HLA-DQA1*02:01 with lcSSc, and an exclusive association of HLA-DQA1*05:01 with dcSSc. Similarly, private associations were detected in HLA-DRB1*08:01 and confirmed the previously reported association of HLA-DRB1*07:01 with ACA-positive patients, as opposed to the HLA-DPA1*02:01 and HLA-DQB1*03:01 alleles associated with ATA presentation. Conclusions This study confirms the contribution of HLA class II and reveals a novel association of HLA class I with SSc, suggesting novel pathways of disease pathogenesis. Furthermore, we describe specific HLA associations with SSc clinical and serological subtypes that could serve as biomarkers of disease severity and progression.This work was supported by the Spanish Ministry of Science and Innovation (grant ref. SAF2015-66761-P and RTI20181013 (32-B-100)), Red de Investigación en Inflamación y Enfermedades Reumáticas from Instituto de Salud Carlos III (RD16/0012/0013) and grants from National Institutes of Health (R01AR073284) and DoD (W81XWH-16-1-0296). MAH was funded by the Spanish Ministry of Science and Innovation through the Juan de la Cierva Incorporacion program (ref. IJC2018-035131-I). GO, AB and ALH were supported by the NIHR Manchester Biomedical Research Centre and Versus Arthritis (grant ref 21754)

Diffusing Capacity of the Lungs for Carbon Monoxide and Echocardiographic Parameters in Identifying Mild Pulmonary Hypertension in the EUSTAR Cohort of Patients With Systemic Sclerosis

Pulmonary hypertension; Screening; Systemic sclerosisHipertensió pulmonar; Cribratge; Esclerosi sistèmicaHipertensión pulmonar; Cribado; Esclerosis sistémicaBackground The 2022 European Society of Cardiology/European Respiratory Society guidelines define pulmonary hypertension (PH) as a resting mean pulmonary artery pressure (mPAP) > 20 mm Hg at right heart catheterization (RHC). Previously, patients with an mPAP between 21 and 24 mm Hg were classified in a “gray zone” of unclear clinical significance. Research Question What is the diagnostic performance of the main parameters used for PH screening in detecting patients with systemic sclerosis (SSc) with an mPAP of 21 to 24 mm Hg at RHC? Study Design and Methods Patients with SSc from the European Scleroderma Trials and Research (EUSTAR) database with available tricuspid annular plane systolic excursion (TAPSE), systolic PAP (sPAP), and mPAP data were included. Patients with mPAP 21 to 24 mm Hg and patients with mPAP ≤ 20 mm Hg were considered for the analysis. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were calculated. Results TAPSE/sPAP was lower in the group of patients with SSc with mPAP 21 to 24 mm Hg than in the non-PH group (0.58 [0.46-0.72] vs 0.69 [0.57-0.81] mm/mm Hg, respectively; P < .01). No difference was found in other parameters between the two groups. Diffusing capacity of the lungs for carbon monoxide < 80% of the predicted value had the highest sensitivity (88.9%) and NPV (80%), but the lowest specificity (18.2%) and PPV (30.8%) in detecting patients with SSc with mPAP 21 to 24 mm Hg. TAPSE/sPAP < 0.55 mm/mm Hg had the highest specificity (78.9%), PPV (50%), and accuracy (68.1%); its NPV was 75.4%, and its sensitivity was 45.1%. Interpretation In this study, diffusing capacity of the lungs for carbon monoxide < 80% of the predicted value was the parameter with the highest sensitivity and NPV in detecting patients with SSc with mPAP 21 to 24 mm Hg. TAPSE/sPAP < 0.55 mm/mm Hg had the highest specificity, PPV, and accuracy and, therefore, can be a useful additional parameter to decrease the number of unnecessary RHCs

Complement component C4 structural variation and quantitative traits contribute to sex-biased vulnerability in systemic sclerosis

Genetic association study; Quantitative trait; Systemic sclerosisEstudi d'associació genètica; Tret quantitatiu; Esclerosi sistèmicaEstudio de asociación genética; Rasgo cuantitativo; Esclerosis sistémicaCopy number (CN) polymorphisms of complement C4 play distinct roles in many conditions, including immune-mediated diseases. We investigated the association of C4 CN with systemic sclerosis (SSc) risk. Imputed total C4, C4A, C4B, and HERV-K CN were analyzed in 26,633 individuals and validated in an independent cohort. Our results showed that higher C4 CN confers protection to SSc, and deviations from CN parity of C4A and C4B augmented risk. The protection contributed per copy of C4A and C4B differed by sex. Stronger protection was afforded by C4A in men and by C4B in women. C4 CN correlated well with its gene expression and serum protein levels, and less C4 was detected for both in SSc patients. Conditioned analysis suggests that C4 genetics strongly contributes to the SSc association within the major histocompatibility complex locus and highlights classical alleles and amino acid variants of HLA-DRB1 and HLA-DPB1 as C4-independent signals.This work was supported by grant RTI2018101332-B-100 funded by MCIN/AEI/10.13039/501100011033 by “ERDF A way of making Europe”, Red de Investigación en Inflamación y Enfermedades Reumáticas (RIER) from Instituto de Salud Carlos III (RD16/0012/0013). This work has received funding from the Innovative Medicines Initiative 1 & 2 Joint Undertaking (JU) under grant agreements No 115565 (PRECISESADS) and No 831434 (3TR). The JU receives support from the European Union’s FP7 and Horizon 2020 research and innovation programs and EFPIA. MAH was supported by the Juan de la Cierva Incorporacion program, grant IJC2018-035131-I funded by MCIN/AEI/10.13039/501100011033. This work is dedicated to the memory of Annette Kerick (1945-2020)

The Effect of Body Fat Distribution on Systemic Sclerosis

Mendelian randomization; Obesity; Systemic sclerosisAleatorización mendeliana; Obesidad; Esclerosis sistémicaAleatorització mendeliana; Obesitat; Esclerosi sistèmicaObesity contributes to a chronic proinflammatory state, which is a known risk factor to develop immune-mediated diseases. However, its role in systemic sclerosis (SSc) remains to be elucidated. Therefore, we conducted a two-sample mendelian randomization (2SMR) study to analyze the effect of three body fat distribution parameters in SSc. As instrumental variables, we used the allele effects described for single nucleotide polymorphisms (SNPs) in different genome-wide association studies (GWAS) for SSc, body mass index (BMI), waist-to-hip ratio (WHR) and WHR adjusted for BMI (WHRadjBMI). We performed local (pHESS) and genome-wide (LDSC) genetic correlation analyses between each of the traits and SSc and we applied several Mendelian randomization (MR) methods (i.e., random effects inverse-variance weight, MR-Egger regression, MR pleiotropy residual sum and outlier method and a multivariable model). Our results show no genetic correlation or causal relationship between any of these traits and SSc. Nevertheless, we observed a negative causal association between WHRadjBMI and SSc, which might be due to the effect of gastrointestinal complications suffered by the majority of SSc patients. In conclusion, reverse causality might be an especially difficult confounding factor to define the effect of obesity in the onset of SSc.This work was supported by grant RTI2018101332-B-100 funded by MCIN/AEI/10.13039/501100011033 and by “ERDF A way of making Europe” funded by the European Union. Red de Investigación en Inflamación y Enfermedades Reumáticas (RIER) from Instituto de Salud Carlos III (RD16/0012/0013). 115565. LB-C was funded by Grant IJC2018-038026-I funded by MCIN/AEI/10.13039/501100011033. MA-H is a recipient of a Miguel Servet fellowship (CP21/00132) from Instituto de Salud Carlos III (Spanish Ministry of Science and Innovation). EL-I was funded by Grant IJC2019-040080-I funded by MCIN/AEI/10.13039/501100011033. GV-M was funded by Grant PRE2019-087586 funded by MCIN/AEI/10.13039/501100011033 and by “ESF Investing in your future”

Contribution of Telomere Length to Systemic Sclerosis Onset: A Mendelian Randomization Study

Mendelian randomization; Systemic sclerosis; Telomere lengthAleatorització mendeliana; Esclerosi sistèmica; Longitud dels telòmersAleatorización mendeliana; Esclerosis sistémica; Longitud de los telómerosAlthough previous studies have suggested a relationship between telomere shortening and systemic sclerosis (SSc), the association between these two traits remains poorly understood. The objective of this study was to assess the causal relationship between telomere length in leukocytes (LTL) and SSc using the two-sample Mendelian randomization approach, with the genome-wide association study data for both LTL and SSc. The results of inverse-variance weighted regression (OR = 0.716 [95% CI 0.528–0.970], p = 0.031) and the Mendelian randomization pleiotropy residual sum and outlier method (OR = 0.716 [95% CI 0.563–0.911], p = 0.035) indicate an association between telomere length and SSc. Specifically, longer genetically predicted LTL is associated with a reduced risk of SSc. Sensitivity tests highlight the significant roles of the variants rs10936599 and rs2736100 annotated to the TERC and TERT genes, respectively. Our findings suggest an influence of telomere length in leukocytes on the development of SSc.This work was supported by Redes de Investigación Cooperativa Orientadas a Resultados en Salud (RICORS) (RD21/0002/0039) funded by Instituto de Salud Carlos III (ISCIII) from the Spanish Ministry of Science and Innovation. M.A.H. is a recipient of a Miguel Servet fellowship (CP21/00132) from ISCIII. G.V.M was funded by Grant PRE2019-087586 funded by MCIN/AEI/10.13039/501100011033 and by “ESF Investing in your future”. I.R.M was supported by the program FPU (FPU21/02746) funded by the Spanish Ministry of University

Standardized incidence ratios and risk factors for cancer in patients with systemic sclerosis: Data from the Spanish Scleroderma Registry (RESCLE)

Anticentromere antibody; Cancer; Systemic sclerosisAnticuerpo anticentrómero; Cáncer; Esclerosis sistémicaAnticòs anticentròmer; Càncer; Esclerosi sistèmicaAim Patients with systemic sclerosis (SSc) are at increased risk of cancer, a growing cause of non–SSc-related death among these patients. We analyzed the increased cancer risk among Spanish patients with SSc using standardized incidence ratios (SIRs) and identified independent cancer risk factors in this population. Material and methods Spanish Scleroderma Registry data were analyzed to determine the demographic characteristics of patients with SSc, and logistic regression was used to identify cancer risk factors. SIRs with 95% confidence intervals (CIs) relative to the general Spanish population were calculated. Results Of 1930 patients with SSc, 206 had cancer, most commonly breast, lung, hematological, and colorectal cancers. Patients with SSc had increased risks of overall cancer (SIR 1.48, 95% CI 1.36–1.60; P < 0.001), and of lung (SIR 2.22, 95% CI 1.77–2.73; P < 0.001), breast (SIR 1.31, 95% CI 1.10–1.54; P = 0.003), and hematological (SIR 2.03, 95% CI 1.52–2.62; P < 0.001) cancers. Cancer was associated with older age at SSc onset (odds ratio [OR] 1.22, 95% CI 1.01–1.03; P < 0.001), the presence of primary biliary cholangitis (OR 2.35, 95% CI 1.18–4.68; P = 0.015) and forced vital capacity <70% (OR 1.8, 95% CI 1.24–2.70; P = 0.002). The presence of anticentromere antibodies lowered the risk of cancer (OR 0.66, 95% CI 0.45–0.97; P = 0.036). Conclusions Spanish patients with SSc had an increased cancer risk compared with the general population. Some characteristics, including specific autoantibodies, may be related to this increased risk.This work was financed in part by the Autoimmune Diseases Study Group of the Spanish Society of Internal Medicine

Circulating Cell Biomarkers in Pulmonary Arterial Hypertension: Relationship with Clinical Heterogeneity and Therapeutic Response

Biomarcadores; Disfunción endotelial; Células progenitorasBiomarcadors; Disfunció endotelial; Cèl·lules progenitoresBiomarkers; Endothelial dysfunction; Progenitor cellsBackground: Endothelial dysfunction is central to PAH. In this study, we simultaneously analysed circulating levels of endothelial microvesicles (EMVs) and progenitor cells (PCs) in PAH and in controls, as biomarkers of pulmonary endothelial integrity and evaluated differences among PAH subtypes and as a response to treatment. Methods: Forty-seven controls and 144 patients with PAH (52 idiopathic, 9 heritable, 31 associated with systemic sclerosis, 15 associated with other connective tissue diseases, 20 associated with HIV and 17 associated with portal hypertension) were evaluated. Forty-four patients with scleroderma and 22 with HIV infection, but without PAH, were also studied. Circulating levels of EMVs, total (CD31+CD42b−) and activated (CD31+CD42b−CD62E+), as well as circulating PCs (CD34+CD133+CD45low) were measured by flow cytometry and the EMVs/PCs ratio was computed. In treatment-naïve patients, measurements were repeated after 3 months of PAH therapy. Results: Patients with PAH showed higher numbers of EMVs and a lower percentage of PCs, compared with healthy controls. The EMV/PC ratio was increased in PAH patients, and in patients with SSc or HIV without PAH. After starting PAH therapy, individual changes in EMVs and PCs were variable, without significant differences being observed as a group. Conclusion: PAH patients present disturbed vascular homeostasis, reflected in changes in circulating EMV and PC levels, which are not restored with PAH targeted therapy. Combined measurement of circulating EMVs and PCs could be foreseen as a potential biomarker of endothelial dysfunction in PAH.This research was funded by grants PI12/00510, PI15/00582 and PI18/00960 from the Institute of Health Carlos III (ISCiii), Spain, co-funded by the European Union (ERDF/ESF); the Catalan Society of Respiratory Medicine (SOCAP); and the Fundación Contra la Hipertensión Pulmonar (FCHP). OTC is the former recipient of a Marie Curie Post-Doctoral Fellowship Award BIOTRACK-IDIBAPS, and the current recipient of a Miguel Servet contract from ISCiii (CP17/00114)

COVID GEAS: COVID-19 National Survey in Patients With Systemic Autoimmune Diseases

COVID-19 infection; Corticosteroids; Systemic autoimmune diseaseInfección por COVID-19; Corticosteroides; Enfermedad autoinmune sistémicaInfecció per COVID-19; Corticosteroides; Malaltia autoimmune sistèmicaObjectives: COVID-19 outcomes in population with systemic autoimmune diseases (SAD) remain poorly understood. The aim was to examine demographic and clinical factors associated with COVID-19 infection in people with rheumatic disease. Methods: Two phases cross-sectional survey of individuals with rheumatic disease in April 2020 and October 2020. COVID infection, severity of disease, age, sex, smoking status, underlying rheumatic disease diagnosis, comorbidities and rheumatic disease medications taken immediately prior to infection were analyzed. Results: A total of 1,529 individuals with autoimmunity disease diagnosis were included. Out of 50 positive patients, 21 required telephone medical assistance, 16 received assessment by primary care physician, 9 were evaluated in Emergency Department and 4 patient required hospitalization. Multivariate analysis was performed without obtaining differences in any of the systemic autoimmune diseases. Regarding the treatments, significant differences were found (p 0.011) in the treatment with anti-TNF-alpha agents with OR 3.422 (1.322–8.858) and a trend to significance (p 0.094) was observed in patients receiving mycophenolate treatment [OR 2.016 (0.996–4-081)]. Conclusions: Anti-TNF-alpha treatment was associated with more than 3-fold risk of suffering from SARS-CoV-2 infection, although in all cases infection was mild. Cumulative incidence in patients with SAD was up to 5 times higher than general population but with great differences between autoimmune diseases.This work was supported by SEMAIS

Impact of interstitial lung disease on the survival of systemic sclerosis with pulmonary arterial hypertension

Respiratory tract diseases; Systemic sclerosisMalalties del tracte respiratori; Esclerosi sistèmicaEnfermedades del tracto respiratorio; Esclerosis sistémicaTo assess severity markers and outcomes of patients with systemic sclerosis (SSc) with or without pulmonary arterial hypertension (PAH-SSc/non-PAH-SSc), and the impact of interstitial lung disease (ILD) on PAH-SSc. Non-PAH-SSc patients from the Spanish SSc registry and PAH-SSc patients from the Spanish PAH registry were included. A total of 364 PAH-SSc and 1589 non-PAH-SSc patients were included. PAH-SSc patients had worse NYHA-functional class (NYHA-FC), worse forced vital capacity (FVC) (81.2 ± 20.6% vs 93.6 ± 20.6%, P < 0.001), worse tricuspid annular plane systolic excursion (TAPSE) (17.4 ± 5.2 mm vs 19.9 ± 6.7 mm, P < 0.001), higher incidence of pericardial effusion (30% vs 5.2%, P < 0.001) and similar prevalence of ILD (41.8% vs. 44.9%). In individuals with PAH-SSc, ILD was associated with worse hemodynamics and pulmonary function tests (PFT). Up-front combination therapy was used in 59.8% and 61.7% of patients with and without ILD, respectively. Five-year transplant-free survival rate was 41.1% in PAH-SSc patients and 93.9% in non-PAH-SSc patients (P < 0.001). Global survival of PAH-SSc patients was not affected by ILD regardless its severity. The multivariate survival analysis in PAH-SSc patients confirmed age at diagnosis, worse NYHA-FC, increased PVR, reduced DLCO, and lower management with up-front combination therapy as major risk factors. In conclusion, in PAH-SSc cohort risk of death was greatly increased by clinical, PFT, and hemodynamic factors, whereas it was decreased by up-front combination therapy. Concomitant ILD worsened hemodynamics and PFT in PAH-SSc but not survival regardless of FVC impairment

Intravenous Cyclophosphamide Pulse Therapy in the Treatment of Systemic Sclerosis-Related Interstitial Lung Disease: A Long Term Study

Interstitial lung disease (ILD) frequently complicates systemic sclerosis (SSc). Cyclophosphamide (CYC) is a promising immunosuppressive therapy for SSc-related ILD. Our objective was to investigate the effectiveness of an intravenous CYC (iv CYC) pulse regime in SSc-related ILD during treatment and thereafter. In a prospective observational study ten consecutive patients with SSc-related ILD were treated with iv CYC in a pulse regime lasting from 6 to 24 months. Clinical status, pulmonary functional testing (PFT) and high resolution computed tomography (HRCT) of the chest were evaluated at enrolment and 6, 12 and 24 months thereafter. After treatment withdrawal, patients were followed up every 6 months with PFT and chest HRCT to monitor lung disease. Clinical improvement was apparent in 8 out of 10 patients. The median values of forced vital capacity (FVC), forced expiratory volume in the first second (FEV1) and diffusion lung capacity for carbon monoxide (DLCO) as well as ground-glass pattern on HRCT did not change significantly after 6, 12 and 24 months of therapy. The follow-up continued in 8 out of 10 patients after treatment withdrawal for a median of 26.5 months (range: 12-48 months). The final median FVC was 54.5% of predicted value (interquartile range, IQR= 31.6%-94%). Only one patient suffered a FVC deterioration greater than 10%, even though less than 160 ml. The final median DLCO was 68% of predicted value (IQR=38.3-83.6%). Only 2 patients who developed pulmonary arterial hypertension deteriorated their DLCO values of more than 15%. An iv CYC pulse regimen over 24 months may stabilize pulmonary activity in patients with SSc-related ILD during the course of treatment and for a median of 26.5 months thereafter