Persisting mortality gap in systemic lupus erythematosus; a population-based study on juvenile- and adult-onset SLE in Norway 1999-2022.

OBJECTIVE: To estimate mortality and survival rates of systemic lupus erythematosus (SLE) in a contemporary, population-based setting and assess potential influences by time, sex, ethnicity, classification criteria and age at diagnosis. METHODS: We assessed mortality and survival in the Nor-SLE cohort, which includes all chart-review confirmed SLE cases resident in Southeast Norway (population 2.9 million) 1999-2017. Study end was at death, emigration, or 1 October 2022. We defined juvenile SLE by age <16 years at diagnosis. For standardized mortality rate (SMR) estimates, we applied 15 population controls per case, all matched for age, sex, residency, and ethnicity. We analyzed survival by Kaplan-Meier and risk factors by cox regression. RESULTS: The Nor-SLE cohort included 1558 SLE cases, of whom 749 were incident and met the 2019 European Alliance of Associations for Rheumatology and American College of Rheumatology (2019-EA) classification criteria. SMR was increased to 1.8 (95% CI 1.6-2.2) in incident adult-onset SLE but did not differ between females and males. Survival rates at 5-, 10-, 15 and 20-years were lower in incident adult-onset SLE than in matched controls. In multivariable analysis, lupus nephritis associated with decreased survival, while sex did not. Separate, long-term mortality analyses in the total Nor-SLE cohort showed that SMR peaked at 7.2 (95% CI 3.3-14) in juvenile-onset SLE (n = 93) and fell gradually by increasing age at SLE diagnosis. CONCLUSION: This study shows persistence of a mortality gap between adult-onset SLE and controls at population level and provides indications of worryingly high mortality in juvenile-onset SLE.

Gastrointestinal symptom severity and progression in systemic sclerosis.

OBJECTIVES: To evaluate the severity and evolution of patient-reported gastrointestinal tract (GIT) symptoms in systemic sclerosis (SSc) patients, assess predictive factors for progression and determine the impact of standard of care treatment. METHODS: SSc patients from the Leiden and Oslo cohorts were included. We assessed clinical data and patient-reported GIT symptoms measured by the validated University of California, Los-Angeles Gastrointestinal-tract (UCLA-GIT) score at baseline and annually. GIT severity and progression was determined. Logistic regression was applied to identify risk factors associated with baseline GIT symptom severity. Linear mixed-effect models were applied to assess progression in GIT symptom burden and to identify predictive factors. We repeated all analysis in patients with early disease (inception cohort) to exclude the effect of longstanding disease and increase insights in development of GIT symptom burden early in the disease course. RESULTS: We included 834 SSc patients with baseline UCLA GIT scores, 454 from Leiden and 380 from Oslo. In the total cohort, 28% reported moderate-severe GIT symptoms at baseline, with increased risk for severity conferred by ACA, smoking and corticosteroid use, while use of calcium channel blockers appeared protective. In the inception cohort, 23% reported moderate-severe GIT symptoms at baseline, with increased risk for females and with smoking. Over time, symptom burden increased mainly for reflux/bloating. Female sex and ACA predicted GIT symptom progression. CONCLUSION: High GIT symptom burden is present early in SSc disease course. Both for prevalence and for progression of GIT symptom burden, female sex and smoking were identified as risk factors.

Multidimensional tracking of phenotypes and organ involvement in a complete nationwide systemic sclerosis cohort.

OBJECTIVE: SSc is a severe, heterogeneous multi-organ disease where population-based estimates on phenotypic spectrum, overall disease burden and societal impact are largely missing. Here the objective was to provide the first-ever complete national-level data on phenotype and major organ afflictions in SSc. METHODS: A stepwise strategy was applied to find and characterize every SSc patient resident in Norway from 2000 to 2012. First we identified every case in the country registered with an International Classification of Diseases, Tenth Revision code for SSc (M34). Next we manually reviewed all cases coded as M34 to determine whether they met the 1980 ACR and/or 2013 ACR/EULAR classification criteria for SSc and could be included in the Norwegian SSc cohort (Nor-SSc). Finally, all disease features from SSc onset to study end were reviewed. RESULTS: The Nor-SSc cohort included 815 SSc patients. The mean age at diagnosis was 53 years, with 84% females and 77% limited cutaneous SSc. The estimated incidence increased from 4 per million in 2000 to 13 per million in 2012. We identified high cumulative frequencies of internal organ involvement, coexistence of multiple organ afflictions across disease subsets and autoantibody status and stable frequencies of pulmonary arterial hypertension across haemodynamic definitions, but indications of referral-related differences in pulmonary hypertension detection rates across the study area. CONCLUSION: This nationwide cohort study provides new, unbiased evidence for a high disease burden in SSc patients of Caucasian descent and indicates the existence of hurdles preventing equality of assessment across the SSc population.

Tracking Impact of Interstitial Lung Disease in Systemic Sclerosis in a Complete Nationwide Cohort.

Rationale: Interstitial lung disease (ILD) represents a major challenge in systemic sclerosis (SSc), but there are no precise, population-based data on its overall impact, limiting opportunities for screening and management strategies.Objectives: Evaluate impact of ILD in a unique, nationwide, population-based SSc cohort.Methods: ILD was assessed prospectively in the Norwegian SSc (Nor-SSc) cohort, including all 815 patients with SSc resident in the country from 2000 to 2012. Lung high-resolution computed tomography (HRCT) scans were available for fibrosis quantification at baseline (n = 650, 80%) and follow-up. Pulmonary function tests were assessed at baseline (n = 703, 86%) and follow-up. Vital status and standardized mortality ratios (SMRs) were estimated at study end (2018) in the 630 incident Nor-SSc cases and 15 individually matched control subjects. Cumulative survival rates were computed.Measurements and Main Results: At baseline, 50% of the subjects with SSc (n = 324) had ILD by HRCT and 46% displayed pulmonary function declines consistent with ILD progression. Mortality correlated with extent of lung fibrosis as SMR increased from 2.2 with no fibrosis to 8.0 with greater than 25% fibrosis. SMR was inversely related to baseline FVC% and increased at all FVC levels below 100%. In patients with normal-range baseline FVC (80-100%), the 5- and 10-year survival rates correlated with presence or absence of lung fibrosis, being 83% and 80%, respectively, with no fibrosis and 69% and 56%, respectively, with lung fibrosis (P = 0.03).Conclusions: The mere presence of ILD at baseline appears to affect outcome in SSc, suggesting that all patients with SSc should undergo a baseline pulmonary function test and lung HRCT screening to diagnose ILD early and tailor further management.

Mortality and causes of death across the systemic connective tissue diseases and the primary systemic vasculitides.

Objectives: Studies assessing relative mortality risks across the spectrum of systemic inflammatory rheumatic diseases are largely missing. In this study, we wanted to estimate standard mortality ratios (SMRs) and causes of death in an ethnically homogeneous cohort covering all major CTDs and primary systemic vasculitides (PSVs). Methods: We prospectively followed all incident CTD and PSV cases included in the Norwegian CTD and vasculitis registry (NOSVAR) between 1999 and 2015. Fifteen controls for each patient matched for sex and age were randomly drawn from the Norwegian National Population Registry. Causes of death were obtained from the National Cause of Death Register, death certificates and hospital charts. Results: The cohort included 2140 patients (1534 with CTD, 606 with PSV). During a mean follow-up time of 9 years, 279 of the patients (13%) died, compared with 2864 of 32 086 (9%) controls (P < 0.001). Ten years after diagnosis, the lowest survival was 60% in dcSSc, 73% in anti-synthetase syndrome (ASS) and 75% in lcSSc. In the CTD group, the highest SMRs were observed in dcSSc (SMR 5.8) and ASS (SMR 4.1). In the PSV group, Takayasu arteritis (SMR 2.5) and ANCA-associated vasculitis (SMR 1.5) had the highest SMRs. Major causes of death were cardiovascular disease (CTD 27%, PSV 28%), neoplasms (CTD 25%, PSV 27%), chronic respiratory disease (CTD 20%, PSV10%) and infections (CTD 9%, PSV 16%). Conclusion: We observed premature deaths across the spectrum of CTDs and PSVs, with highest SMRs in dcSSc and ASS. The overall mortality was highest in the CTD group.

Frequencies of borderline pulmonary hypertension before and after the DETECT algorithm: results from a prospective systemic sclerosis cohort.

Objective: The DETECT algorithm was developed for screening patients with SSc at high risk of pulmonary arterial hypertension (PAH). We evaluated the impact of this algorithm in a SSc population. Methods: Patients from the unselected, prospective Oslo University Hospital SSc study were divided into the Early and DETECT cohorts, respectively, depending on whether an incident right heart catheterization (RHC) was performed before (2009-13) or after (2014-17) the DETECT algorithm was instituted. A PAH diagnosis and patient risk stratification (low, intermediate and high risk) were performed according to 2015 European Society of Cardiology guidelines. Results: At the time of the incident RHC, PAH frequency was similar between the DETECT (15/84 with PAH; 18%) and Early (16/77; 21%) cohorts, but more patients had borderline pulmonary hypertension (PH) in the DETECT (31%) than in the Early (17%) cohort. PAH risk levels were distributed differently. In the DETECT cohort, 27% and 27% were at low and high risk, respectively, at the time of PAH diagnosis. In the Early cohort, 19 and 44% were at low and high risk, respectively. A follow-up RHC, performed after [mean (SD)] 2.4 (1.8) years, showed that 39% of patients with borderline PH in the Early cohort had developed PAH. Conclusion: The DETECT algorithm did not alter PAH incidence in this unselected SSc population. However, it appeared to affect the risk distribution at the time of PAH diagnosis and increased the frequency of borderline PH cases. These findings may translate into novel opportunities for earlier PAH treatment and, possibly, prevention.

Associations between anti-Ro52 antibodies and lung fibrosis in mixed connective tissue disease.

OBJECTIVE: MCTD is a chronic, immune-mediated disorder defined by the combined presence of serum anti-RNP antibodies and distinct clinical features, including progressive lung fibrosis. The aim of the study was to evaluate the potential impact of anti-SSA (i.e. Ro52 and Ro60) and anti-SSB autoantibodies as markers for disease outcomes in MCTD. METHODS: Stored serum samples from 113 patients included in the cross-sectional, nationwide Norwegian MCTD cohort were screened for the presence of anti-Ro52, anti-Ro60 and anti-SSB by a commercial line immunoassay. Correlation analyses were carried out with clinical parameters, including quantitative lung fibrosis scores by high-resolution CT. Lung fibrosis was defined by reticular pattern changes according to the Fleischner Society CT criteria for interstitial lung disease. RESULTS: Anti-Ro52 antibodies were present in 29%, anti-Ro60 in 19% and anti-SSB in 6% of the MCTD sera. High-resolution CT scoring identified lung fibrosis in 38 of 113 (34%) MCTD patients. Anti-Ro52 antibodies were detected in 50% (19 of 38) of the MCTD patients with lung fibrosis and in 19% (14 of 75) without lung fibrosis (P < 0.001). The odds ratio for the presence of anti-Ro52 antibodies in lung fibrosis was 4.4 (95% CI 1.8, 10.3). Anti-Ro52 antibodies were equally frequent in patients with mild to moderate (eight of 17; 44%) and severe fibrosis (11 of 21; 52%). Anti-Ro52 was not associated with any of the other clinical parameters assessed, nor was anti-Ro60 or anti-SSB. CONCLUSION: Our cross-sectional data suggest that anti-Ro52 antibodies may serve as a potential marker for lung fibrosis in MCTD.

Endostatin is higher and associated with pulmonary involvement in primary Sjögren's syndrome.

OBJECTIVES: To investigate serum levels of endostatin in a well characterised cohort of patients with primary Sjögren's syndrome (pSS) and healthy controls (HC) and assess associations between these mediators and clinical parameters. METHODS: All patients (n=144) were recruited from the Norwegian systemic connective tissue disease and vasculitis registry (NOSVAR) and fulfilled American-European classification criteria for pSS. Pulmonary involvement was based on clinical symptoms and abnormal findings on high-resolution computed tomography of the lungs. The controls were 100 healthy blood donors. Serum levels of endostatin was determined by enzyme immunoassay. RESULTS: We found higher mean levels of serum endostatin in patients with pSS compared with the controls (p<0.001). The patients with interstitial lung disease (ILD) had higher levels compared with those without pulmonary involvement. CONCLUSIONS: Our results indicate that endostatin is increased in patients with pSS and particularly in those with ILD.

Prevalence and clinical characteristics of adult polymyositis and dermatomyositis; data from a large and unselected Norwegian cohort.

OBJECTIVES: The occurrence of polymyositis (PM) and dermatomyositis (DM) in the general population is largely unknown and unbiased data on clinical and laboratory features in PM/DM are missing. Here, we aim to identify and characterise every PM/DM patient living in southeast Norway (denominator population 2.64 million), 2003-2012. METHOD: Due to the structure of the Norwegian health system, all patients with PM/DM are followed at public hospitals. Hence, all public hospital databases in southeast Norway were screened for patients having ICD-10 codes compatible with myositis. Manual chart review was then performed to identify all cases meeting the Peter & Bohan and/or Targoff classification criteria for PM/DM. RESULTS: The ICD-10 search identified 3160 potential myositis patients, but only 208/3160 patients met the Peter & Bohan criteria and 230 the Targoff criteria (100 PM, 130 DM). With 56 deaths during the observation period, point prevalence of PM/DM was calculated to 8.7/100 000. Estimated annual incidences ranged from 6 to 10 /1 000 000, with peak incidences at 50-59 (DM) and 60-69 years (PM). Myositis specific antibodies (Jo-1, PL-7, PL-12, signal recognition particle (SRP) and Mi-2) were present in 53% (109/204), while 137/163 (87%) had pathological muscle MRI. Frequent clinical features included myalgia (75%), arthritis (41%) dyspnoea (62%) and dysphagia (58%). Positive anti-Jo-1, present in 39% of DM and 22% of PM cases, was associated with dyspnoea, arthritis and mechanic hands. CONCLUSIONS: Our data indicate that the population prevalence of PM/DM in Caucasians is quite low, but underscores the complexity and severity of the disorders.

The HLA profiles of mixed connective tissue disease differ distinctly from the profiles of clinically related connective tissue diseases.

OBJECTIVE: The Norwegian nationwide MCTD cohort was established to obtain unbiased data on key disease issues, and thereby reappraise the concept of MCTD. In the current study, the aims were to obtain detailed HLA profile data on the large Norwegian MCTD cohort and compare these with the HLA profiles of ethnically matched healthy controls and related CTD controls. METHODS: HLA profiles, determined by sequence-based typing of HLA-B* and DRB1*, were compared between four control groups of Norwegian ancestry, SLE (n = 96), SSc (n = 95), PM/DM (n = 84), healthy individuals (n = 282), the complete MCTD cohort (n = 155) and MCTD subsets defined by key clinical parameters. RESULTS: HLA-B*08 [odds ratio (OR) 2.05, P = 1.31 × 10(-4)) and DRB1*04:01 (OR 2.82, P = 3.64 × 10(-8)) were identified as risk alleles for MCTD, while DRB1*04:04, DRB1*13:01 and DRB1*13:02 were protective. Risk alleles for SLE and PM/DM were B*08 and DRB1*03:01. SSc risk was associated with DRB1*08:01. Analyses of MCTD subsets identified B*18 [OR 3.32 (95% CI 1.38, 8.01)] and DRB1*03:01 [OR 1.83 (95% CI 1.03, 3.25)] as independent risk factors for lung fibrosis. CONCLUSION: Novel HLA alleles associated with MCTD and disease subsets were identified and DRB1*04:01 was confirmed as a major risk allele. Altogether, the data reinforce the notion of MCTD as a disease entity distinct from SLE, SSc and PM/DM.

Long-term experience with rituximab in anti-synthetase syndrome-related interstitial lung disease.

OBJECTIVE: To retrospectively evaluate the efficacy and safety of rituximab (Rtx) treatment in patients with anti-synthetase syndrome (ASS) and severe interstitial lung disease (ILD). METHODS: Patients with severe ILD and >12 months follow-up post-Rtx were identified from the Oslo University Hospital ASS cohort (n = 112). Clinical data, including pulmonary function tests (PFTs), were retrospectively collected from medical reports. Extent of ILD pre-, and post-Rtx was scored on thin-section high-resolution CT (HRCT) images and expressed as a percentage of total lung volume. Muscle strength was evaluated by manual muscle testing of eight muscle groups (MMT8). RESULTS: Altogether, 34/112 ASS patients had received Rtx; 24/34 had severe ILD and >12 months follow-up post-Rtx (median 52 months). In these 24 patients, the median percentage of predicted forced vital capacity, forced expiratory volume in 1 s (FEV1) and diffusing capacity of the lungs for carbon monoxide (DLCO) increased by 24%, 22% and 17%, respectively, post-Rtx. Seven patients (all with disease duration <12 months and/or acute onset/exacerbation of ILD) had >30% improvement in all three PFTs. HRCT analysis showed a median 34% reduction in ILD extent post-Rtx. MMT8 score increased post-Rtx. During follow-up, 7/34 (21%) Rtx-treated ASS patients died; 6/7 deaths were related to infections. The mortality rate in the Rtx-treated group was comparable to that of the remaining ASS cohort (25/78 deceased; 32%). CONCLUSION: This study, which included 24 Rtx-treated ASS patients with severe ILD, reports improved PFTs after a median 52 months follow-up post-Rtx. The best outcome was observed in patients with a disease duration <12 months and/or acute onset/exacerbation of ILD. The study indicates that Rtx could be a treatment option for selected ASS patients, but infections should be given attention.

Generalized bone loss in early rheumatoid arthritis patients followed for ten years in the biologic treatment era.

BACKGROUND: Osteoporosis is a well-known extra articular manifestation in rheumatoid arthritis (RA). Biologic disease modifying anti rheumatic drugs (DMARDs) has been shown to be superior to synthetic DMARDs to reduce bone destruction including generalized bone loss in RA. Our aim was to study short- and long term changes in hip and spine bone mineral density (BMD) in early RA patients treated during the first decade with available biologic DMARDs. METHODS: RA patients diagnosed at an out-patient clinic between 1999 and 2001 were consecutively enrolled. Demographic, disease and treatment data were collected and BMD was assessed by dual energy X-ray absorptiometry at baseline and after 2, 5 and 10 years. RESULTS: The 92 included RA patients had a baseline mean age (SD) of 50.9 (13.3) years and symptom duration of 12.4 (6.7) months, 62.0% were women and 66.3% were RF positive. In the first 2 years ever use of biologic DMARDs was 18.5%, synthetic DMARDs 91.3% and prednisolone 62.0% whereas the figures for the subsequent 8 years were 62.6%, 89.2% and 51.4%, respectively. The annual rate of BMD loss in the first 2 years and the subsequent 8 years was at femoral neck -1.00% vs. -0.56%, at total hip -0.96% vs. -0.41% and at spine L1-4 -0.42% vs. 0.00%. CONCLUSIONS: Our study adds evidence that aggressive anti-inflammatory treatment including biologic DMARDs reduces the rate of bone loss in RA. Indicating that the burden of osteoporosis is reduced in RA patients treated in clinical practice in the new millennium.

Declining Incidence of Systemic Lupus Erythematosus in Norway 1999-2017: Data From a Population Cohort Identified by International Classification of Diseases, 10th Revision Code and Verified by Classification.

OBJECTIVE: The goal of this study was to provide complete, robust data on annual systemic lupus erythematosus (SLE) incidence rates over nearly two decades from the Southeast Norway area (2.9 million inhabitants) and assess accuracy of SLE-specific International Classification of Diseases (ICD) codes for SLE diagnosis. METHODS: From administrative databases, we identified all cases International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10) coded as SLE during 1999 through 2017 in Southeast Norway. We manually reviewed the chart of every case ICD-10 coded as SLE to either confirm or reject SLE diagnosis. Using SLE classification criteria, we classified all cases with confirmed SLE. We estimated annual incidence rates of classified SLE, and subsets, defined by age at diagnosis, sex, and parental country of birth. The chi-square test was applied for linear time-trend analyses of incidence. RESULTS: Among the 3,488 cases ICD-10 coded as SLE, chart reviews confirmed SLE diagnosis in 1,558 (45%), of which 797 had new-onset disease during 1999 through 2017. Annual SLE incidence rates fell during 1999 to 2017. The fall was most pronounced in female persons 50 to 59 years old at diagnosis, in whom incidence fell from 3.4 to 1.1 per 100,000 persons (P trend < 0.001). Concurrent ecological data from the study area showed a 74% reduction in prescriptions of menopausal hormone treatment. Accuracy of ICD-10 codes for incident SLE diagnosis was acceptable in juveniles and young adults (up to 20 years) but otherwise low. CONCLUSION: In a presumably complete population-based cohort, we identified decreasing incidence of SLE, especially among female persons 50 to 59 years old. Although reasons for declining incidence are not clear, ecological data indicate a possible role of environmental factors, for example, menopausal hormone treatments.

Clinical pulmonary involvement in primary Sjogren's syndrome: prevalence, quality of life and mortality--a retrospective study based on registry data.

OBJECTIVE: The aim of the present study was to describe the prevalence of clinical pulmonary manifestations in primary SS (pSS), and based on registry data, to assess quality of life (QoL) and mortality in these patients. METHODS: Patients with pSS consecutively included in the Norwegian systemic CTD and vasculitis registry (NOSVAR) were investigated for pulmonary manifestations when presenting with clinical pulmonary symptoms. Pulmonary involvement was defined as typical abnormalities identified with high-resolution CT (HRCT) and/or pulmonary function tests (PFTs). RESULTS: Among patients referred from our primary area, Oslo (n = 117), lung involvement was found in 26 patients (22%). In our total cohort (n = 216), 59 patients (27%) were affected. A higher rate of pulmonary complications and trends towards longer disease duration and higher age indicated a selection of more complicated cases referred from outside our primary area. Abnormal HRCTs were found in 50 patients (23%) and PFTs in 34 patients (16%). The Medical Outcomes Study 36-Item Short-Form Health Survey Physical Functioning subscore, was significantly reduced in patients with lung involvement (P = 0.03). Furthermore, a 4-fold increased risk of dying after 10 years of disease among patients with lung involvement (n = 10, 17%) compared with those without lung involvement (n = 7, 4.5%) (P = 0.002) was found. CONCLUSION: We found a high population-based prevalence of clinical pulmonary involvement (22%) among patients with pSS. Moreover, patients with lung involvement had reduced QoL represented by the subscale Physical Functioning, and mortality was increased.

Prevalence of pulmonary hypertension in an unselected, mixed connective tissue disease cohort: results of a nationwide, Norwegian cross-sectional multicentre study and review of current literature.

OBJECTIVES: The aim of this study was to assess the overall prevalence of pulmonary hypertension (PH) in an unselected MCTD cohort and review the current knowledge with a systematic database search. METHODS: A nationwide multicentre cohort of 147 adult MCTD patients were initially screened for PH by echocardiography, high-resolution computed tomography (HRCT), pulmonary function tests and N-terminal pro-brain natriuretic peptide (NT-proBNP) and then followed up for a mean of 5.6 years. Right-sided heart catheterization was performed when estimated pulmonary artery systolic pressure was >40 mmHg on echocardiography. PH was diagnosed according to the 2009 European Society of Cardiology and European Respiratory Society guidelines. RESULTS: At inclusion, 2.0% (3/147) had established PH. Two additional PH patients were identified during follow-up, giving a total PH frequency in the cohort of 3.4% (5/147). All five had elevated serum NT-proBNP. Two had isolated pulmonary arterial hypertension (PAH) and three PH associated with interstitial lung disease (PH-ILD). Three PH patients died during follow-up. Nine other patients in the cohort also died, but none of them had echocardiographic signs of PH prior to death. CONCLUSION: The data from the current unselected MCTD cohort suggest that the prevalence of PH is much lower than expected from previous studies but confirm the seriousness of the disease complication.

Differential sensitivity of the 2020 revised comprehensive diagnostic criteria and the 2019 ACR/EULAR classification criteria across IgG4-related disease phenotypes: results from a Norwegian cohort.

BACKGROUND: We investigated sensitivity of the 2020 Revised Comprehensive Diagnostic Criteria (RCD) and the 2019 ACR/EULAR classification criteria across the four identified IgG4-related disease (IgG4-RD) phenotypes: "Pancreato-Hepato-Biliary", "Retroperitoneum and Aorta", "Head and Neck-limited" and "Mikulicz' and Systemic" in a well-characterized patient cohort. METHODS: We included adult patients diagnosed with IgG4-RD after comprehensive clinical assessment at Oslo University Hospital in Norway. We assigned patients to IgG4-RD phenotypes based on pattern of organ involvement and assessed fulfillment of RCD and 2019 ACR/EULAR classification criteria. Differences between phenotype groups were analyzed using one-way ANOVA for continuous variables, and contingency tables for categorical variables. RESULTS: The study cohort included 79 IgG4-RD patients assigned to the "Pancreato-Hepato-Biliary" (22.8%), Retroperitoneum and Aorta" (22.8%) "Head and Neck-limited" (29.1%), and "Mikulicz' and Systemic" (25.3%) phenotype groups, respectively. While 72/79 (91.1%) patients in total fulfilled the RCD, proportion differed across phenotype groups and was lowest in the "Retroperitoneum and Aorta" group (66.7%, p < 0.001). Among the 57 (72.2%) patients meeting the 2019 ACR/EULAR classification criteria, proportion was again lowest in the "Retroperitoneum and Aorta" group (27.8%, p < 0.001). CONCLUSION: The results from this study indicate that IgG4-RD patients having the "Retroperitoneum and Aorta" phenotype less often fulfill diagnostic criteria and classification criteria than patients with other IgG4-RD phenotypes. Accordingly, this phenotype is at risk of being systematically selected against in observational studies and randomized clinical trials, with potential implications for patients, caregivers and future definitions of IgG4-RD.

Prevalence of systemic sclerosis in south-east Norway.

OBJECTIVE: To assess the prevalence of SSc in south-east Norway. METHODS: The survey was conducted in south-east Norway with a denominator population of 2,707,012, 56% of the total Norwegian population. All SSc patients living in the study area between 1 January 1999 and 31 December 2009 were included. Patients were identified by five overlapping acquisition routes, including all the rheumatology departments, private rheumatologists and the dermatology department in the study area. Only cases meeting the 1980 ACR and/or the Medsger and LeRoy classification criteria were included. The patients were assigned to three clinical subsets: limited SSc, lcSSc or dcSSc. RESULTS: At the end of the study period, a total of 269 patients fulfilled the ACR and/or the Medsger and LeRoy SSc criteria, giving a point prevalence of 9.9/100,000 (95% CI 8.8, 11.2). The estimated prevalences of lSSc, lcSSc and dcSSc were 1.3/100,000, 6.9/100,000 and 1.8/100,000 (95% CIs 0.9, 1.8; 5.8, 7.8; 1.4, 2.5), respectively. The mean age at onset was 47 years and the female:male ratio was 3.8:1. The prevalence estimates of SSc in the 10 different counties in south-east Norway varied between 5.2 and 14.4/100,000 (95% CIs 2.8, 8.8; 10.3, 19.6). CONCLUSION: This study establishes baseline estimates of the occurrence and disease characteristics in a large, unselected group of Norwegian SSc patients. Our data suggest that the prevalence of SSc in Norway is comparable with other northern European countries, supporting the notion of a north-south gradient of SSc in Europe with the lowest prevalence in northern Europe.

Serum markers of cardiac complications in a systemic sclerosis cohort.

Primary cardiac involvement is one of the leading causes of mortality in systemic sclerosis (SSc), but little is known regarding circulating biomarkers for cardiac SSc. Here, we aimed to investigate potential associations between cardiac SSc and candidate serum markers. Serum samples from patients of the Oslo University SSc cohort and 100 healthy controls were screened against two custom-made candidate marker panels containing molecules deemed relevant for cardiopulmonary and/or fibrotic diseases. Left (LV) and right ventricular (RV) dysfunction was assessed by protocol echocardiography, performed within three years from serum sampling. Patients suspected of pulmonary hypertension underwent right heart catheterization. Vital status at study end was available for all patients. Descriptive analyses, logistic and Cox regressions were conducted to assess associations between cardiac SSc and candidate serum markers. The 371 patients presented an average age of 57.2 (± 13.9) years. Female sex (84%) and limited cutaneous SSc (73%) were predominant. Association between LV diastolic dysfunction and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) (OR 0.41, 95% CI 0.21-0.78, p = 0.007) was identified. LV systolic dysfunction defined by global longitudinal strain was associated with angiopoietin 2 (ANGPT2) (OR 3.42, 95% CI 1.52-7.71, p = 0.003) and osteopontin (OPN) (OR 1.95, 95% CI 1.08-3.52, p = 0.026). RV systolic dysfunction, measured by tricuspid annular plane systolic excursion, was associated to markers of LV dysfunction (ANGPT2, OPN, and TRAIL) (OR 1.67, 95% CI 1.11-2.50, p = 0.014, OR 1.86, 95% CI 1.25-2.77, p = 0.002, OR 0.32, 95% CI 0.15-0.66, p = 0.002, respectively) and endostatin (OR 1.86, 95% CI 1.22-2.84, p = 0.004). In conclusion, ANGPT2, OPN and TRAIL seem to be circulating biomarkers associated with both LV and RV dysfunction in SSc.

Target organ expression and biomarker characterization of chemokine CCL21 in systemic sclerosis associated pulmonary arterial hypertension.

Introduction: Systemic sclerosis (SSc) is a heterogenous disorder that appears to result from interplay between vascular pathologies, tissue fibrosis and immune processes, with evidence for deregulation of chemokines, which normally control immune trafficking. We recently identified altered levels of chemokine CCL21 in SSc associated pulmonary arterial hypertension (PAH). Here, we aimed to define target organ expression and biomarker characteristics of CCL21. Materials and methods: To investigate target organ expression of CCL21, we performed immunohistochemistry (IHC) on explanted lung tissues from SSc-PAH patients. We assessed serum levels of CCL21 by ELISA and Luminex in two well-characterized SSc cohorts from Oslo (OUH, n=552) and Zurich (n=93) University hospitals and in 168 healthy controls. For detection of anti-CCl21 antibodies, we performed protein array analysis applying serum samples from SSc patients (n=300) and healthy controls. To characterize circulating CCL21 in SSc, we applied immunoprecipitation (IP) with antibodies detecting both full length and tailless and a custom-made antibody detecting only the C-terminal of CCL21. IP products were analyzed by SDS-PAGE/western blot and Mass spectrometry (MS). Results: By IHC, we found that CCL21 was mainly expressed in the airway epithelial cells of SSc patients with PAH. In the analysis of serum levels of CCL21 we found weak correlation between Luminex and ELISA (r=0.515, p<0.001). Serum levels of anti-CCL21 antibodies were higher in SSc patients than in healthy controls (p<0.001), but only 5% of the SSc population were positive for anti-CCL21 antibodies in SSc, and we found no correlation between anti-CCl21 and serum levels of CCL21. By MS, we only identified peptides located within amino acid (aa) 23-102 of CCL21, indicating that CCL21 in SSc circulate as a truncated protein without the C-terminal tail. Conclusion: This study demonstrates expression of CCL21 in epithelial lung tissue from SSc patients with PAH, and indicate that CCL21 in SSc circulates as a truncated protein. We extend previous observations indicating biomarker potential of CCL21, but find that Luminex is not suitable as platform for biomarker analyses. Finally, in vivo generated anti-CCL21 antibodies exist in SSc, but do not appear to modify serum CCL21 levels in patients with SSc-PAH.

Oral distress in primary Sjögren's syndrome: implications for health-related quality of life.

The aims of the study were to evaluate oral distress in patients with primary Sjögren's syndrome (pSS) compared with age- and sex-matched Norwegian normative data, to estimate the occurrence of oral symptoms in pSS, and to evaluate the impact of oral distress on health-related quality of life (HRQoL). The Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36) was used to assess HRQoL, and the Oral Health Impact Profile 14 (OHIP-14) was used to measure oral distress. Of the 246 pSS patients invited to participate in the study, 177 (72%) responded. Data were analysed for the female participants (n = 163). Significant deviations from normative estimates were found in all OHIP-14 item results, and the findings indicated a high level of oral distress among the pSS patients. Health-related quality of life was decreased among pSS patients, with the largest deviations from normative estimates related to general health and role physical. The patients with high levels of oral distress scored significantly lower than patients with low levels of oral distress in five of the SF-36 subscales, indicating that oral conditions have a marked impact on general quality of life. In conclusion, oral distress in pSS is pronounced and severe, and should receive increased attention with a view to improving the quality of life for these patients.