Quantitative outcome measures for systemic sclerosis-related Microangiopathy - Reliability of image acquisition in Nailfold Capillaroscopy

BACKGROUND

Nailfold capillaroscopic parameters hold increasing promise as outcome measures for clinical trials in systemic sclerosis (SSc). Their inclusion as outcomes would often naturally require capillaroscopy images to be captured at several time points during any one study. Our objective was to assess repeatability of image acquisition (which has been little studied), as well as of measurement.

METHOD

41 patients (26 with SSc, 15 with primary Raynaud's phenomenon) and 10 healthy controls returned for repeat high-magnification (300×) videocapillaroscopy mosaic imaging of 10 digits one week after initial imaging (as part of a larger study of reliability). Images were assessed in a random order by an expert blinded observer and 4 outcome measures extracted: (1) overall image grade and then (where possible) distal vessel locations were marked, allowing (2) vessel density (across the whole nailfold) to be calculated (3) apex width measurement and (4) giant vessel count. Intra-rater, intra-visit and intra-rater inter-visit (baseline vs. 1week) reliability were examined in 475 and 392 images respectively. A linear, mixed-effects model was used to estimate variance components, from which intra-class correlation coefficients (ICCs) were determined.

RESULTS

Intra-visit and inter-visit reliability estimates (ICCs) were (respectively): overall image grade, 0.97 and 0.90; vessel density, 0.92 and 0.65; mean vessel width, 0.91 and 0.79; presence of giant capillary, 0.68 and 0.56. These estimates were conditional on each parameter being measurable.

CONCLUSION

Within-operator image analysis and acquisition are reproducible. Quantitative nailfold capillaroscopy, at least with a single observer, provides reliable outcome measures for clinical studies including randomised controlled trials.

Clinical determinants of elevated systolic pulmonary artery pressure measured by transthoracic Doppler echocardiography in early systemic sclerosis

OBJECTIVES

To explore the prevalence and clinical associations of elevated systolic pulmonary artery pressure (sPAP), measured by Transthoracic Doppler-echocardiography (TTE) in patients with early systemic sclerosis (SSc).

METHODS

A cross-sectional analysis of the prospective EULAR Scleroderma Trial and Research (EUSTAR) database was performed. SSc patients with <3 years from the first non-Raynaud's phenomenon (RP) symptom at baseline EUSTAR visit, were selected. Elevated sPAP was defined as sPAP>40 mmHg on baseline TTE. First visit SSc related variables, including disease subsets, antibodies and visceral involvement, were examined.

RESULTS

From 1,188 patients, 81% were women. Mean (SD) age at first non-RP symptom was 50 (14) years, 55% had limited cutaneous SSc (lcSSc) and 42% active disease. Elevated sPAP was found in 17% of patients, both lcSSc and diffuse cutaneous SSc (dcSSc). In lcSSc, older age at first non-RP symptom, ACA positivity, joint contractures, restrictive defect and lower DLCO, were independently associated with elevated sPAP. In dcSSc, older age at first non-RP symptom, longer time between RP onset and first non-RP symptom, digital ulcers, cardiac blocks, and proteinuria were associated with elevated sPAP.

CONCLUSIONS

The prevalence of elevated sPAP on TTE in early SSc patients is considerable. Association with cardiac, lung and renal involvement suggests that, although some patients might have pulmonary arterial hypertension, others may present pulmonary hypertension secondary to lung or heart involvement. Our findings emphasize the need to consider right heart catheterisation in selected early SSc patients with PH suspicion, to clearly determine the cause of PH.

Mapping and predicting mortality from systemic sclerosis

OBJECTIVES

To determine the causes of death and risk factors in systemic sclerosis (SSc).

METHODS

Between 2000 and 2011, we examined the death certificates of all French patients with SSc to determine causes of death. Then we examined causes of death and developed a score associated with all-cause mortality from the international European Scleroderma Trials and Research (EUSTAR) database. Candidate prognostic factors were tested by Cox proportional hazards regression model by single variable analysis, followed by a multiple variable model stratified by centres. The bootstrapping technique was used for internal validation.

RESULTS

We identified 2719 French certificates of deaths related to SSc, mainly from cardiac (31%) and respiratory (18%) causes, and an increase in SSc-specific mortality over time. Over a median follow-up of 2.3 years, 1072 (9.6%) of 11 193 patients from the EUSTAR sample died, from cardiac disease in 27% and respiratory causes in 17%. By multiple variable analysis, a risk score was developed, which accurately predicted the 3-year mortality, with an area under the curve of 0.82. The 3-year survival of patients in the upper quartile was 53%, in contrast with 98% in the first quartile.

CONCLUSION

Combining two complementary and detailed databases enabled the collection of an unprecedented 3700 deaths, revealing the major contribution of the cardiopulmonary system to SSc mortality. We also developed a robust score to risk-stratify these patients and estimate their 3-year survival. With the emergence of new therapies, these important observations should help caregivers plan and refine the monitoring and management to prolong these patients' survival.

Raynaud's phenomenon and its impact on activities in daily life during one year of follow-up in early systemic sclerosis

OBJECTIVE

To investigate Raynaud's phenomenon (RP) and its impact on daily life activities during 1 year of follow-up in early systemic sclerosis (SSc).

METHOD

Fourteen SSc patients with a median disease duration of 2 years were enrolled in the study. Every 7 weeks the patients completed a 7 day diary documenting the frequency and duration of RP attacks, the activity causing the attack, and how they handled the attack. The patients also recorded in the diary daily self-assessments of the difficulties with RP, using a 0-10 ordinal scale according to the Raynaud's Condition Score.

RESULTS

Ninety-eight RP weekly diaries were analysed. The median number of RP attacks varied between six and nine per week, and the median score reflecting the difficulty associated with the attacks varied between 2.0 and 2.9. No difference was found in the number of attacks or the difficulties associated with them between winter, spring, and autumn. Fewer attacks and less difficulty were reported in August than in any of the other documented weeks (p < 0.05). In all diaries, all patients reported RP attacks associated with domestic activities. The use of heating devices varied during the follow-up. In February, all patients except one used such devices, while about half of the group used devices during the rest of the year.

CONCLUSIONS

Difficulties resulting from RP are present and disabling all year round, which underscore the importance of intense vasoactive therapy and non-pharmacological strategies throughout the year.

Brief Report: IRF4 Newly Identified as a Common Susceptibility Locus for Systemic Sclerosis and Rheumatoid Arthritis in a Cross-Disease Meta-Analysis of Genome-Wide Association Studies

OBJECTIVE

Systemic sclerosis (SSc) and rheumatoid arthritis (RA) are autoimmune diseases that have similar clinical and immunologic characteristics. To date, several shared SSc-RA genetic loci have been identified independently. The aim of the current study was to systematically search for new common SSc-RA loci through an interdisease meta-genome-wide association (meta-GWAS) strategy.

METHODS

The study was designed as a meta-analysis combining GWAS data sets of patients with SSc and patients with RA, using a strategy that allowed identification of loci with both same-direction and opposite-direction allelic effects. The top single-nucleotide polymorphisms were followed up in independent SSc and RA case-control cohorts. This allowed an increase in the sample size to a total of 8,830 patients with SSc, 16,870 patients with RA, and 43,393 healthy controls.

RESULTS

This cross-disease meta-analysis of the GWAS data sets identified several loci with nominal association signals (P < 5 × 10(-6) ) that also showed evidence of association in the disease-specific GWAS scans. These loci included several genomic regions not previously reported as shared loci, as well as several risk factors that were previously found to be associated with both diseases. Follow-up analyses of the putatively new SSc-RA loci identified IRF4 as a shared risk factor for these 2 diseases (Pcombined  = 3.29 × 10(-12) ). Analysis of the biologic relevance of the known SSc-RA shared loci identified the type I interferon and interleukin-12 signaling pathways as the main common etiologic factors.

CONCLUSION

This study identified a novel shared locus, IRF4, for the risk of SSc and RA, and highlighted the usefulness of a cross-disease GWAS meta-analysis strategy in the identification of common risk loci.

Decreased platelet size is associated with platelet activation and anti-phospholipid syndrome in systemic lupus erythematosus

Objectives

. SLE is an autoimmune disease with increased cardiovascular morbidity and platelet activation. In the general population, increased platelet size predicts platelet reactivity and cardiovascular disease. The aim of this study was to investigate whether platelet size related to platelet activation and cardiovascular disease in SLE.

Methods

. Fresh blood samples from SLE patients ( n = 148), healthy volunteers ( n = 79) and disease controls ( n = 40) were analysed for platelet size and activation by flow cytometry, ELISA and cell count. Associations to manifest cardiovascular disease, venous thrombosis and APS were adjusted for traditional cardiovascular risk factors using logistic regression analysis.

Results

. SLE patients had decreased platelet size as compared with healthy controls ( P = 0.003). In SLE, decreased platelet size was related to increased platelet activation, in particular microparticle formation ( P < 0.0001, r = -0.46) and release of serotonin from dense granules ( P < 0.001, r = 0.57). SLE patients with aCL had decreased platelet size ( P = 0.02) and aCL decreased platelet size in vitro ( P = 0.007). In contrast to the general population, increased platelet size was not associated with cardiovascular disease. Instead, decreased platelet size was associated with secondary APS, even after adjusting for traditional cardiovascular risk factors ( P = 0.01, odds ratio 3.58).

Conclusion

. Platelet size is decreased in SLE patients and associated with microparticle formation and APS. Future studies are needed to determine the underlying mechanism(s) as well as the potential predictive value of small platelets for disease complications in SLE.

Information, social support and coping in patients with pulmonary arterial hypertension or chronic thromboembolic pulmonary hypertension-A nationwide population-based study

OBJECTIVE

Pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH) decrease life expectancy for affected patients. The aim was to describe the perceptions of received information regarding diagnosis, treatment and management, as well as social support and coping perceived by patients with PAH or CTEPH.

METHODS

A descriptive, national cohort survey that included patients from all PAH-centres in Sweden. A quantitative methodology was employed where all patients received three questionnaires, QLQ-INFO25, Mastery Scale and Social Network & Support Scale.

RESULTS

The response rate was 74% (n=325), mean age 66±14years, 71% were female and 69% were diagnosed with PAH and 31% with CTEPH. Sixty percent of respondents were satisfied with the received information and felt it was helpful. Best experiences were of information in the areas of medical tests (70%) and the disease (61%). Forty-five percent wanted more information. Men described their social network as more accessible than women (p=0.004). Those living alone had a lower coping ability.

CONCLUSION

Despite a high level of satisfaction with the received information, almost half of the patients wanted more information.

PRACTICE IMPLICATIONS

Regular repeating or giving new information should be an ongoing process in the care of patients at the PAH-centres.

Respiratory symptoms are poor predictors of concomitant chronic obstructive pulmonary disease in patients with primary Sjögren's syndrome

Involvement of the respiratory system, in particular dry airways and chronic obstructive pulmonary disease (COPD), is common in patients with primary Sjögren’s syndrome (pSS). As respiratory symptoms are also common in pSS patients and may have different etiologies, we wanted to evaluate the amount and impact of respiratory symptoms in out-patients with pSS and to assess if such symptoms are related to concomitant COPD. The St George’s Respiratory Questionnaire (SGRQ) was used to assess respiratory symptoms. SGRQ scores were compared between 51 consecutive pSS patients, in an out-patient setting, and 80 population-based controls. The patients were also studied by pulmonary function tests and CT scans of the lungs to assess signs of obstructive airway disease, including COPD, as well as to assess signs of interstitial lung disease (ILD). 41 and 18% of pSS patients were found to have COPD and radiographic signs of ILD, respectively. pSS patients had significantly higher SGRQ scores compared to controls, but no significant differences in SGRQ scores were found between patients with and without COPD. Neither did the small group of pSS patients with ILD significantly differ in SGRQ scores in comparison to patients without ILD. Respiratory symptoms were common in pSS, but were not more common in patients with concomitant COPD. Since pulmonary involvement in pSS is associated with an increased mortality and respiratory symptoms is a poor marker for pulmonary involvement, we suggest that pulmonary function tests should be performed liberally in all pSS patients regardless of symptoms.

Treatment outcome in early diffuse cutaneous systemic sclerosis: the European Scleroderma Observational Study (ESOS)

Objectives

The rarity of early diffuse cutaneous systemic sclerosis (dcSSc) makes randomised controlled trials very difficult. We aimed to use an observational approach to compare effectiveness of currently used treatment approaches.

Methods

This was a prospective, observational cohort study of early dcSSc (within three years of onset of skin thickening). Clinicians selected one of four protocols for each patient: methotrexate, mycophenolate mofetil (MMF), cyclophosphamide or ‘no immunosuppressant’. Patients were assessed three-monthly for up to 24 months. The primary outcome was the change in modified Rodnan skin score (mRSS). Confounding by indication at baseline was accounted for using inverse probability of treatment (IPT) weights. As a secondary outcome, an IPT-weighted Cox model was used to test for differences in survival.

Results

Of 326 patients recruited from 50 centres, 65 were prescribed methotrexate, 118 MMF, 87 cyclophosphamide and 56 no immunosuppressant. 276 (84.7%) patients completed 12 and 234 (71.7%) 24 months follow-up (or reached last visit date). There were statistically significant reductions in mRSS at 12 months in all groups: −4.0 (−5.2 to −2.7) units for methotrexate, −4.1 (−5.3 to −2.9) for MMF, −3.3 (−4.9 to −1.7) for cyclophosphamide and −2.2 (−4.0 to −0.3) for no immunosuppressant (p value for between-group differences=0.346). There were no statistically significant differences in survival between protocols before (p=0.389) or after weighting (p=0.440), but survival was poorest in the no immunosuppressant group (84.0%) at 24 months.

Conclusions

These findings may support using immunosuppressants for early dcSSc but suggest that overall benefit is modest over 12 months and that better treatments are needed.

Trial registration number

NCT02339441.

Intra-and inter-observer reliability of nailfold videocapillaroscopy - A possible outcome measure for systemic sclerosis-related microangiopathy

OBJECTIVES

Our aim was to assess the reliability of nailfold capillary assessment in terms of image evaluability, image severity grade ('normal', 'early', 'active', 'late'), capillary density, capillary (apex) width, and presence of giant capillaries, and also to gain further insight into differences in these parameters between patients with systemic sclerosis (SSc), patients with primary Raynaud's phenomenon (PRP) and healthy control subjects.

METHODS

Videocapillaroscopy images (magnification 300×) were acquired from all 10 digits from 173 participants: 101 patients with SSc, 22 with PRP and 50 healthy controls. Ten capillaroscopy experts from 7 European centres evaluated the images. Custom image mark-up software allowed extraction of the following outcome measures: overall grade ('normal', 'early', 'active', 'late', 'non-specific', or 'ungradeable'), capillary density (vessels/mm), mean vessel apical width, and presence of giant capillaries.

RESULTS

Observers analysed a median of 129 images each. Evaluability (i.e. the availability of measures) varied across outcome measures (e.g. 73.0% for density and 46.2% for overall grade in patients with SSc). Intra-observer reliability for evaluability was consistently higher than inter- (e.g. for density, intra-class correlation coefficient [ICC] was 0.71 within and 0.14 between observers). Conditional on evaluability, both intra- and inter-observer reliability were high for grade (ICC 0.93 and 0.78 respectively), density (0.91 and 0.64) and width (0.91 and 0.85).

CONCLUSIONS

Evaluability is one of the major challenges in assessing nailfold capillaries. However, when images are evaluable, the high intra- and inter-reliabilities suggest that overall image grade, capillary density and apex width have potential as outcome measures in longitudinal studies.

Malignancies in Patients with Anti-RNA Polymerase III Antibodies and Systemic Sclerosis: Analysis of the EULAR Scleroderma Trials and Research Cohort and Possible Recommendations for Screening

OBJECTIVE

To analyze the characteristics of anti-RNA polymerase III antibodies (anti-RNAP3)- positive patients with systemic sclerosis (SSc) in the European League Against Rheumatism Scleroderma Trials and Research group (EUSTAR) registry with a focus on the risk of cancer and the characteristics of malignancies, and the aim to provide guidelines about potential cancer screening in these patients.

METHODS

(1) Analysis of the EUSTAR database: 4986 patients with information on their anti-RNAP3 status were included. (2) Case-control study: additional retrospective data, including malignancy history, were queried in 13 participating EUSTAR centers; 158 anti-RNAP3+ cases were compared with 199 local anti-RNAP3- controls, matched for sex, cutaneous subset, disease duration, and age at SSc onset. (3) A Delphi exercise was performed by 82 experts to reach consensus for cancer screening in anti-RNAP3+ patients.

RESULTS

In the EUSTAR registry, anti-RNAP3 were associated in multivariable analysis with renal crisis and diffuse cutaneous involvement. In the case-control study, anti-RNAP3 were associated with gastric antral vascular ectasia, rapid progression of skin involvement, and malignancies concomitant to SSc onset (OR 7.38, 95% CI 1.61-33.8). When compared with other anti-RNAP3+ patients, those with concomitant malignancies had older age (p < 0.001) and more frequent diffuse cutaneous involvement (p = 0.008). The Delphi exercise highlighted the need for malignancy screening at the time of diagnosis for anti-RNAP3+ patients and tight followup in the following years.

CONCLUSION

Anti-RNAP3+ patients with SSc have a high risk of concomitant malignancy. These results have implications for clinical practice and suggest regular screening for cancer in anti-RNAP3+ patients.

Analysis of complement biomarkers in systemic sclerosis indicates a distinct pattern in scleroderma renal crisis

BACKGROUND

The complement system has been implicated in pathogenesis of systemic sclerosis (SSc). The goal of the present study was to evaluate improved complement biomarkers in SSc.

METHODS

The presence of C4d, reflecting activation of the classical/lectin pathways, C3bBbP corresponding to activation of the alternative pathway, and soluble terminal complement complexes (all complement pathways), was measured in plasma samples by enzyme-linked immunosorbent assay and correlated to clinical parameters. The study included 81 patients with limited cutaneous SSc and 41 with diffuse cutaneous SSc, as well as 47 matched healthy controls and 81 patients with rheumatoid arthritis, 22 with psoriatic arthritis and 20 with ankylosing spondylitis. Skin and kidney biopsies of selected patients were stained to detect deposited C3b as a marker of local complement activation.

RESULTS

Biomarkers of activation of all complement pathways were increased in SSc compared with healthy controls and were similar to those in other rheumatic diseases. When patients with SSc were divided into subgroups, a distinct pattern of complement markers was observed in individuals with scleroderma renal crisis (SRC). By functional assay, we confirmed a significant decrease in complement haemolytic activity in SRC vs. non-SRC patients, indicating complement consumption. Further, we detected glomerular deposits of C3b in some patients with SRC.

CONCLUSIONS

The data indicate that complement activation is an important feature of SRC.