A Longitudinal Analysis of Outcomes of Lupus Nephritis in an International Inception Cohort Using a Multistate Model Approach

Anti-C1q antibodies: a biomarker for diagnosis and management of lupus nephritis. A narrative review

Nephritis is a frequent and severe complication of Systemic Lupus Erythematous (SLE). The clinical course of lupus nephritis (LN) is usually characterized by alternating phases of remission and exacerbation. Flares of LN can lead to deterioration of kidney function, necessitating timely diagnosis and therapy. The presence of autoantibodies against C1q (anti-C1qAb) in the sera of SLE patients has been reported in various studies. Some research suggests that the presence and changes in the titer of anti-C1qAb may be associated with the development of LN, as well as with LN activity and renal flares. However, the exact role of anti-C1qAb in LN remains a subject of debate. Despite variability in the results of published studies, anti-C1qAb hold promise as noninvasive markers for assessing LN activity in SLE patients. Measuring anti-C1qAb levels could aid in diagnosing and managing LN during periods of both inactive disease and renal flares. Nevertheless, larger controlled trials with standardized laboratory assays are necessary to further establish the utility of anti-C1qAb in predicting the reactivation and remission of LN and guiding treatment strategies.

Efficacy of Voclosporin in Proliferative Lupus Nephritis with High Levels of Proteinuria

BACKGROUND

In a phase 3 study of adults with active lupus nephritis, addition of voclosporin to mycophenolate mofetil (MMF) and low-dose glucocorticoids led to significant improvements in the proportion of participants achieving complete and partial renal response as well as sustained reduction in proteinuria. This analysis examined the efficacy and safety of voclosporin in a subgroup of the phase 3 study with proliferative lupus nephritis and high levels of proteinuria.

METHODS

Participants were randomized to oral voclosporin (23.7 mg twice daily) or placebo for 12 months; all participants received MMF and low-dose glucocorticoids. This analysis includes participants with class III or IV (±class V) lupus nephritis and baseline urine protein-creatinine ratio (UPCR) ≥3 g/g. Efficacy end points included complete renal response (UPCR ≤0.5 g/g with stable eGFR, low-dose glucocorticoids, and no rescue medication), partial renal response (≥50% reduction from baseline UPCR), and UPCR over time. Safety outcomes were also assessed.

RESULTS

A total of 148 participants were in the voclosporin ( n =76) and control ( n =72) arms. At 12 months, 34% and 11% of participants in the voclosporin and control arms, respectively, achieved a complete renal response (odds ratio, 4.43; 95% confidence interval [CI], 1.78 to >9.99; P = 0.001). A partial renal response was achieved by 65% of the voclosporin arm and 51% of the control arm at 12 months (odds ratio, 1.60; 95% CI, 0.8 to 3.20; P = 0.18). More voclosporin- than control-treated participants achieved UPCR ≤0.5 g/g (51% versus 26%), and voclosporin-treated participants met this end point significantly earlier (hazard ratio, 2.07; 95% CI, 1.19 to 3.60; P = 0.01). The incidence of adverse events was similar between the arms; mean eGFR values remained stable and within normal range in both arms.

CONCLUSIONS

Addition of voclosporin to MMF and low-dose glucocorticoids resulted in a significantly higher proportion of participants with proliferative lupus nephritis achieving complete and partial renal responses as well as earlier reductions in proteinuria, with no evidence of worsening kidney function.

Genetics of longitudinal kidney function in children and adults with systemic lupus erythematosus

OBJECTIVES

Genome-wide association studies (GWAS) have identified loci associated with estimated glomerular filtration rate (eGFR). Few LN risk loci have been identified to date. We tested the association of SLE and eGFR polygenic risk scores (PRS) with repeated eGFR measures from children and adults with SLE.

METHODS

Patients from two tertiary care lupus clinics that met ≥4 ACR and/or SLICC criteria for SLE were genotyped on the Illumina MEGA or Omni1-Quad arrays. PRSs were calculated for SLE and eGFR, using published weighted GWA-significant alleles. eGFR was calculated using the CKD-EPI and Schwartz equations. We tested the effect of eGFR- and SLE-PRSs on eGFR mean and variance, adjusting for age at diagnosis, sex, ancestry, follow-up time, and clinical event flags.

RESULTS

We included 1158 SLE patients (37% biopsy-confirmed LN) with 36 733 eGFR measures over a median of 7.6 years (IQR: 3.9-15.3). LN was associated with lower within-person mean eGFR [LN: 93.8 (s.d. 26.4) vs non-LN: 101.6 (s.d. 17.7) mL/min per 1.73 m2; P < 0.0001] and higher variance [LN median: 157.0 (IQR: 89.5, 268.9) vs non-LN median: 84.9 (IQR: 46.9, 138.2) (mL/min per 1.73 m2)2; P < 0.0001]. Increasing SLE-PRSs were associated with lower mean eGFR and greater variance, while increasing eGFR-PRS was associated with increased eGFR mean and variance.

CONCLUSION

We observed significant associations between SLE and eGFR PRSs and repeated eGFR measurements, in a large cohort of children and adults with SLE. Longitudinal eGFR may serve as a powerful alternative outcome to LN categories for discovery of LN risk loci.

Short-term Accrual 2019 European League Against Rheumatism/American College of Rheumatology Domains and Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage in Lupus Patients With and Without Nephritis at Disease Onset

OBJECTIVE

To determine in a historical inception cohort the impact of lupus nephritis at disease onset in short-term accrual 2019 European League Against Rheumatism (EULAR)/American College of Rheumatology (ACR) domains. The possible association with treatment and damage was also investigated.

METHODS

One hundred thirty-three consecutive adult systemic lupus erythematosus patients according to the 2019 EULAR/ACR criteria were divided according to the presence (RENAL-lupus) or absence of renal involvement (NONRENAL-lupus) at disease onset. The 2019 EULAR/ACR score and Systemic Lupus International Collaborating Clinics/ACR (SDI) were longitudinally evaluated over 3 years.

RESULTS

RENAL-lupus (n = 49 [36.8%]) and NONRENAL-lupus (n = 84 [63.2%]) were similar regarding age ( p = 0.704), female sex ( p = 0.313), and black race ( p = 0.506). At study entry, RENAL-lupus had higher 2019 EULAR/ACR total domains (30 [12-42] vs. 22 [10-36], p < 0.001) and used more often glucocorticoid ( p < 0.001), mycophenolate mofetil ( p = 0.007), and cyclophosphamide ( p = 0.001). After 3 years, a stable number of domain scores was observed for the RENAL-lupus (30 [12-42] vs. 30 [12-42], p = 0.125), whereas an increase was observed for the NONRENAL-lupus (22 [10-36] vs. 23 [10-40], p < 0.001) compared with baseline. Accordingly, RENAL-lupus patients had a lower frequency of additional domains (3/49 [6.1%] vs. 37/84 [44.0%], p < 0.0001). New kidney involvement occurred in 15 (44.1%) of 34 patients of the NONRENAL-lupus. Both groups evolved with a comparable increase in frequency of patients with damage (SDI ≥1) at the end of the study (23/49 [46.9%] vs. 34/89 [40.54%], p = 0.585) with a similar median of SDI (1 [0-4] vs. 0 [0-2], p = 0.132).

CONCLUSIONS

The distinct pattern of accrual 2019 EULAR/ACR domains in patients with and without nephritis at disease onset suggests that close surveillance for additional organ involvement, including kidney, is mandatory in NONRENAL lupus in the first 3 years of disease. The unexpected comparable early damage in both groups despite milder disease and less intense immunosuppression in NONRENAL lupus reinforces the need for new and tailored therapies for these patients.

Serum miR-342-3p Acts as a Biomarker for Systemic Lupus Erythematosus and Participates in the Disease Progression

Purpose

The aim of this study was to investigate the diagnostic ability and prognostic value of miR-342-3p in SLE patients by detecting the expression level of serum miR-342-3p in SLE patients.

Patients and Methods

The expression level of serum miR-342-3p in all subjects was determined by qRT-PCR technology, and the correlation of miR-342-3p with SLEDAI scores was evaluated using Spearman correlation coefficient. The diagnostic value of miR-342-3p in SLE was assessed using ROC curve. The prognostic value of miR-342-3p in SLE patients was analyzed by Kaplan-Meier survival curve and multivariate COX regression.

Results

The qRT-PCR results showed that the expression level of serum miR-342-3p in SLE patients was significantly lower than that in healthy controls (P < 0.001). Serum miR-342-3p expression level was negatively correlated with SLEDAI scores (r = - 0.810, P < 0.001). The ROC curve suggested that serum miR-342-3p expression level was discriminative between SLE patients and healthy controls. Survival analysis results indicated that SLE patients with low serum miR-342-3p expression had a higher probability of poor prognosis of SLE (Log rank P = 0.003).

Conclusion

The expression level of serum miR-342-3p was valuable in the diagnosis of SLE. Meanwhile, the low expression level of serum miR-342-3p was associated with the poor prognosis of SLE.

Short- and Long-Term Progression of Kidney Involvement in Systemic Lupus Erythematosus Patients with Low-Grade Proteinuria

BACKGROUND AND OBJECTIVES

Lupus nephritis remains a common cause of morbidity and mortality in systemic lupus erythematosus (SLE). Current guidelines recommend performing a kidney biopsy at a urine protein-creatinine ratio of ≥0.5 g/g. However, cross-sectional studies reported a high prevalence of active histologic lupus nephritis lesions, and even chronic irreversible scarring, in patients with low-grade proteinuria. This study was initiated to assess disease progression in patients with SLE and low-grade proteinuria to identify risk factors for progression to overt proteinuria suggestive of clinical lupus nephritis.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Patients with SLE who had an incident urinary protein-creatinine ratio of ≥0.2 and <0.5 g/g without known lupus nephritis were identified from the Einstein Rheumatic Disease Registry. Patients who developed a random urinary protein-creatinine ratio of ≥0.5 g/g with or without biopsy during the follow-up period were defined as "progressors." Patients who progressed to a urinary protein-creatinine ratio of ≥0.5 g/g within 2 years of developing a urinary protein-creatinine ratio of ≥0.2 and <0.5 g/g were defined as "fast progressors," a subgroup expected to benefit most from early biopsies and therapeutic interventions.

RESULTS

Among 151 eligible patients with SLE and low-grade proteinuria at study entry, 76 (50%) progressed to a urinary protein-creatinine ratio of ≥0.5 g/g, of which 44 underwent a clinically indicated biopsy. The median (interquartile range) time from a urinary protein-creatinine ratio of ≥0.2 and <0.5 g/g to progression was 1.2 (0.3-3.0) years. Of the 20 biopsies performed in the first 2 years, 16 specimens showed active, treatable lupus nephritis. Low complement and shorter SLE duration at low-grade proteinuria onset were associated with progression to overt proteinuria across different analyses. Other associated factors included hypertension, diabetes mellitus, younger age, and the presence of hematuria.

CONCLUSIONS

In this longitudinal cohort of patients with SLE and low-grade proteinuria at study entry, over half progressed to a urinary protein-creatinine ratio of ≥0.5 g/g in a short time period.

The Cost-Effectiveness of Belimumab and Voclosporin for Patients with Lupus Nephritis in the United States

BACKGROUND AND OBJECTIVES

Despite existing therapies, people with lupus nephritis progress to kidney failure and have reduced life expectancy. Belimumab and voclosporin are two new disease-modifying therapies recently approved for the treatment of lupus nephritis.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A de novo economic model was developed to estimate the cost-effectiveness of these therapies, including the following health states: "complete response," "partial response," and "active disease" defined by eGFR and proteinuria changes, kidney failure, and death. Short-term data and mean cohort characteristics were sourced from pivotal clinical trials of belimumab (the Belimumab International Study in Lupus Nephritis) and voclosporin (the Aurinia Urinary Protection Reduction Active-Lupus with Voclosporin trial and Aurinia Renal Response in Active Lupus With Voclosporin). Risk of mortality and kidney failure were on the basis of survival modeling using published Kaplan-Meier data. Each drug was compared with the standard of care as represented by the comparator arm in its respective pivotal trial(s) using US health care sector perspective, with a societal perspective also explored.

RESULTS

In the health care perspective probabilistic analysis, the incremental cost-effectiveness ratio for belimumab compared with its control arm was estimated to be approximately $95,000 per quality-adjusted life year. The corresponding incremental ratio for voclosporin compared with its control arm was approximately $150,000 per quality-adjusted life year. Compared with their respective standard care arms, the probabilities of belimumab and voclosporin being cost effective at a threshold of $150,000 per quality-adjusted life year were 69% and 49%, respectively. Cost-effectiveness was dependent on assumptions made regarding survival in response states, costs and utilities in active disease, and the utilities in response states. In the analysis from a societal perspective, the incremental ratio for belimumab was estimated to be approximately $66,000 per quality-adjusted life year, and the incremental ratio for voclosporin was estimated to be approximately $133,000 per quality-adjusted life year.

CONCLUSIONS

Compared with their respective standard care arms, belimumab but not voclosporin met willingness-to-pay thresholds of $100,000 per quality-adjusted life year. Despite potential clinical superiority in the informing trials, there remains high uncertainty around the cost-effectiveness of voclosporin.

A meta-analysis of clinical manifestations in asian systemic lupus erythematous: The effects of ancestry, ethnicity and gender

OBJECTIVES

Systemic lupus erythematosus (SLE) in Asians is a unique patient group that has been thought to present with more severe organ involvement in comparison to their non-Asian counterparts. We set out to perform a meta-analysis to compare clinical manifestations between ancestries, with a focus on Southeast Asian ethnicities and gender.

MATERIALS AND METHODS

A cross-sectional study was performed in conjunction with a meta-analysis to identify differences in prevalences of SLE clinical manifestations. Searches were conducted on Medline for articles comparing between: (i) Asian and non-Asian ancestry; (ii) Southeast Asian ethnicities (Chinese, Malay and Indian); and (iii) male and female Asians. Using random effects model, effect sizes as odd ratios were pooled with DerSimonian and Laird's model.

RESULTS

A total of 13 articles were identified and pooled together with our study for this meta-analysis. Comparing among patients of Asian with Non-Asian/European ancestries, no significance difference was found in severe organ manifestations such as renal and neurological involvement [odds ratio (OR): 1.398, p= 0.320 and OR: 1.224, p= 0.526 respectively]. There was significantly greater proportion of Asian SLE patients with thrombocytopenia compared to non-Asian SLE. Chinese SLE patients were less likely to have oral ulcers compared to Indian SLE patients. Lastly, Asian male SLE patients had greater incidence of renal involvement and thrombocytopenia compared to Asian female SLE patients.

CONCLUSIONS

Severe SLE manifestations such as renal and neurological involvement were not significantly more frequent in Asian SLE compared to non-Asian/European SLE in this analysis.

Pathological mechanisms of abnormal iron metabolism and mitochondrial dysfunction in systemic lupus erythematosus

Introduction: Systemic lupus erythematosus [SLE] is a chronic, autoimmune condition characterized by the formation of autoantibodies directed against nuclear components and by oxidative stress. Recently, a number of studies have demonstrated the essential role of iron in the immune response and there is growing evidence that abnormal iron homeostasis can occur in the chronic inflammatory state seen in SLE. Not only is iron vital for hematopoiesis, it is also important for a number of other key physiological processes, in particular in maintaining healthy mitochondrial function.Areas covered: In this review, we highlight the latest understanding with regards to how patients with SLE may be at risk of cellular iron depletion as a result of both absolute and functional iron deficiency. Furthermore, we aim to explain the latest evidence of mitochondrial dysfunction in the pathogenesis of the disease.Expert opinion: Growing evidence suggests that both abnormal iron homeostasis and subsequent mitochondrial dysfunction can impair effector immune cell function. Through a greater understanding of these abnormalities, therapeutic options that directly target iron and mitochondria may ultimately represent novel treatment targets that may translate into clinical care of patients with SLE in the near future.

Starting off on the right foot: A 22-year-old woman with leg swelling

A previously healthy 22-year-old woman was in the second trimester of her first pregnancy when she developed new lower extremity edema. Her pregnancy course had been unremarkable, and she was receiving routine obstetric care from her family physician. One week prior to admission she developed progressive swelling in her legs.

Management of lupus nephritis: a systematic literature review informing the 2019 update of the joint EULAR and European Renal Association-European Dialysis and Transplant Association (EULAR/ERA-EDTA) recommendations

Objectives

To analyse the current evidence for the management of lupus nephritis (LN) informing the 2019 update of the EULAR/European Renal Association-European Dialysis and Transplant Association recommendations.

Methods

According to the EULAR standardised operating procedures, a PubMed systematic literature review was performed, from January 1, 2012 to December 31, 2018. Since this was an update of the 2012 recommendations, the final level of evidence (LoE) and grading of recommendations considered the total body of evidence, including literature prior to 2012.

Results

We identified 387 relevant articles. High-quality randomised evidence supports the use of immunosuppressive treatment for class III and class IV LN (LoE 1a), and moderate-level evidence supports the use of immunosuppressive treatment for pure class V LN with nephrotic-range proteinuria (LoE 2b). Treatment should aim for at least 25% reduction in proteinuria at 3 months, 50% at 6 months and complete renal response (<500–700 mg/day) at 12 months (LoE 2a-2b). High-quality evidence supports the use of mycophenolate mofetil/mycophenolic acid (MMF/MPA) or low-dose intravenous cyclophosphamide (CY) as initial treatment of active class III/IV LN (LoE 1a). Combination of tacrolimus with MMF/MPA and high-dose CY are alternatives in specific circumstances (LoE 1a). There is low-quality level evidence to guide optimal duration of immunosuppression in LN (LoE 3). In end-stage kidney disease, all methods of kidney replacement treatment can be used, with transplantation having the most favourable outcomes (LoE 2b).

Conclusions

There is high-quality evidence to guide the initial and subsequent phases of class III/IV LN treatment, but low-to-moderate quality evidence to guide treatment of class V LN, monitoring and optimal duration of immunosuppression.

Predictors of the start of declining eGFR in patients with systemic lupus erythematosus

OBJECTIVE

To characterize the longitudinal trajectory of estimated glomerular filtration rate (eGFR) in patients with systemic lupus erythematosus (SLE) and identify predictors of the change in eGFR trajectory.

METHODS

The longitudinal eGFR levels of patients in the Hopkins Lupus Cohort were modelled by piecewise linear regression to evaluate the slope of different line segments. The slopes were classified into declining (≤-4 mL/min/1.73 m² per year), stable (-4 to 4 mL/min/1.73 m² per year), and increasing (≥4 mL/min/1.73 m² per year) states. The transition rate between states and the impact of clinical parameters were estimated by a Markov model.

RESULTS

The analysis was based on 494 SLE patients. At a mean follow-up of 8.8 years, 347 (70.2%), 107 (21.7%), 33 (6.7%), and 7 (1.4%) patients had zero, one, two, and three state transitions, respectively. In patients with no transition, 37 (10.7%), 308 (88.8%), and 2 (0.6%) were in declining, stable, and increasing state, respectively. In patients with one transition, 43 (40.2%) changed from declining to stable state while 29 (27.1%) changed from stable to declining state. When patients were in a non-declining GFR state, those who were younger and African Americans were more likely to transition to a declining GFR state. In adjusted analyses, high blood pressure, C4 and low hematocrit were associated with change from non-declining to declining state. High urine protein-to-creatinine ratio also tended to be associated with change from non-declining to declining state. African American patients were less likely to move from declining to non-declining state. Use of prednisone was associated with change from declining to non-declining state.

CONCLUSIONS

Patients with high blood pressure, low complement C4, low haematocrit, and high urine protein-to-creatinine ratio are more likely to have a declining eGFR trajectory, while the use of prednisone stabilizes the declining eGFR trajectory.

Pentraxin 3: A promising therapeutic target for autoimmune diseases

Pentraxin 3 (PTX3) is a prototypic humoral soluble pattern recognition molecule that exerts a pivotal role in innate immune response and inflammation, as well as in tissue damage and remodeling. Recently, emerging evidence has revealed that PTX3 is involved in the occurrence and development of various autoimmune diseases, such as rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), ankylosing spondylitis (AS), systemic sclerosis (SSc), inflammatory bowel disease (IBD), multiple sclerosis (MS) and psoriasis, etc. In this review, we have succinctly summarized the complex immunological functions of PTX3 and mostly focused on recent findings of the pleiotropic activities played by PTX3 in the pathogenesis of autoimmune diseases, aiming at hopefully offering possible future therapeutic alternatives.

Risk of Renal Failure Within 10 or 20 Years of Systemic Lupus Erythematosus Diagnosis

OBJECTIVE

The frequency of endstage renal disease (ESRD) from systemic lupus erythematosus (SLE) in the United States has not improved over the last few decades in large population datasets. Understanding the risk factors for renal failure in SLE could lead to earlier detection of lupus nephritis and potentially more effective treatments in those with markers of poor prognosis.

METHODS

The Hopkins Lupus Cohort, comprising 2528 patients was used. One hundred fifty-one patients experienced renal failure after SLE diagnosis, defined as dialysis or renal transplant. We estimated the risk of renal failure in subgroups defined by demographics, laboratory tests, and the American College of Rheumatology/Systemic Lupus International Collaborating Clinics (ACR/SLICC) classification criteria satisfied within 1 year of SLE diagnosis.

RESULTS

The overall incidence of renal failure within 20 years of SLE diagnosis was 8.4%. The risk was much higher (20.0%) among those who experienced proteinuria within the first year of diagnosis. Demographic predictors included African American ethnicity [rate ratio (RR) 1.82, P = 0.0012] and age ≥ 40 years at SLE diagnosis (RR 0.51 vs those with diagnosis at < 30 yrs of age, P = 0.019). Among immunologic markers, low C3 was a strong predictor of renal failure (RR 2.00, P = 0.0011).

CONCLUSION

Proteinuria within the first year of diagnosis of SLE is one of the most important predictors of ESRD. Our data also confirm African American ethnicity, younger age at SLE diagnosis, and low C3 as strong predictors of renal failure.

Neuropsychiatric events in systemic lupus erythematosus: a longitudinal analysis of outcomes in an international inception cohort using a multistate model approach

OBJECTIVES

Using a reversible multistate model, we prospectively examined neuropsychiatric (NP) events for attribution, outcome and association with health-related quality of life (HRQoL), in an international, inception cohort of systemic lupus erythematosus (SLE) patients.

METHODS

Annual assessments for 19 NP events attributed to SLE and non-SLE causes, physician determination of outcome and patient HRQoL (short-form (SF)-36 scores) were measured. Time-to-event analysis and multistate modelling examined the onset, recurrence and transition between NP states.

RESULTS

NP events occurred in 955/1827 (52.3%) patients and 592/1910 (31.0%) unique events were attributed to SLE. In the first 2 years of follow-up the relative risk (95% CI) for SLE NP events was 6.16 (4.96, 7.66) and non-SLE events was 4.66 (4.01, 5.43) compared with thereafter. Patients without SLE NP events at initial assessment had a 74% probability of being event free at 10 years. For non-SLE NP events the estimate was 48%. The majority of NP events resolved over 10 years but mortality was higher in patients with NP events attributed to SLE (16%) versus patients with no NPSLE events (6%) while the rate was comparable in patients with non-SLE NP events (7%) compared with patients with no non-SLE events (6%). Patients with NP events had lower SF-36 summary scores compared with those without NP events and resolved NP states (p<0.001).

CONCLUSIONS

NP events occur most frequently around the diagnosis of SLE. Although the majority of events resolve they are associated with reduced HRQoL and excess mortality. Multistate modelling is well suited for the assessment of NP events in SLE.

Identifying damage clusters in patients with systemic lupus erythematosus

AIM

Systemic lupus erythematosus (SLE) causes irreversible damage to organ systems. Recently, evidence has been obtained for subphenotypes of SLE. This study aimed to identify damage clusters and compare the associated clinical manifestations, SLE disease activity, mortality, and genetic risk scores (GRS).

METHODS

The study was conducted on the Hanyang BAE lupus cohort. Patients with disease duration <5 years were excluded to minimize confounding effects of disease duration. They were grouped into 3 clusters based on the Systemic Lupus International Collaborating Clinics Damage Index using k-means cluster analysis.

RESULTS

Among the 1130 analyzed patients, musculoskeletal damage was most prevalent (20.2%), followed by ocular (11.4%), renal (10.5%), and neuropsychiatric damage (10.2%). Three significantly different damage clusters were identified. Patients in cluster 1 (n = 824) showed the least damage. Cluster 2 (n = 195) was characterized by frequent renal (55.4%) and ocular (58.0%) damage, and cluster 3 (n = 111) was dominated by neuropsychiatric (100%) and musculoskeletal damage (35.1%). Cluster 2 had the highest adjusted mean AMS (adjusted mean SLE Disease Activity Index score; mean ± SD: 5.4 ± 2.9), while cluster 3 had the highest mortality (14.4%). Weighted GRS did not differ significantly between the clusters.

CONCLUSION

Patients in prevalent renal and ocular damage cluster had the highest AMS scores, while the cluster with frequent neuropsychiatric damage had the highest mortality.

Establishing Surrogate Kidney End Points for Lupus Nephritis Clinical Trials: Development and Validation of a Novel Approach to Predict Future Kidney Outcomes

OBJECTIVE

End points currently used in lupus nephritis (LN) clinical trials lack uniformity and questionably reflect long-term kidney survival. This study was undertaken to identify short-term end points that predict long-term kidney outcomes for use in clinical trials.

METHODS

A database of 944 patients with LN was assembled from 3 clinical trials and 12 longitudinal cohorts. Variables from the first 12 months of treatment after diagnosis of active LN (prediction period) were assessed as potential predictors of long-term outcomes in a 36-month follow-up period. The long-term outcomes examined were new or progressive chronic kidney disease (CKD), severe kidney injury (SKI), and the need for permanent renal replacement therapy (RRT). To predict the risk for each outcome, hazard index tools (HITs) were derived using multivariable analysis with Cox proportional hazards regression.

RESULTS

Among 550 eligible subjects, 54 CKD, 55 SKI, and 22 RRT events occurred. Variables in the final CKD HIT were prediction-period CKD status, 12-month proteinuria, and 12-month serum creatinine level. The SKI HIT variables included prediction-period CKD status, International Society of Nephrology (ISN)/Renal Pathology Society (RPS) class, 12-month proteinuria, 12-month serum creatinine level, race, and an interaction between ISN/RPS class and 12-month proteinuria. The RRT HIT included age at diagnosis, 12-month proteinuria, and 12-month serum creatinine level. Each HIT validated well internally (c-indices 0.84-0.92) and in an independent LN cohort (c-indices 0.89-0.92).

CONCLUSION

HITs, derived from short-term kidney responses to treatment, correlate with long-term kidney outcomes, and now must be validated as surrogate end points for LN clinical trials.

Circulating Pentraxin3-Specific B Cells Are Decreased in Lupus Nephritis

Background: Pentraxin3 (PTX3) is overexpressed in kidneys of patients developing lupus nephritis (LN). Active LN is associated with reduced anti-PTX3 antibodies. However, abnormalities of B cell differentiation against PTX3 have not been characterized in systemic lupus erythematosus (SLE).

Objective: Characterization of PTX3-specific (PTX3⁺) B cells in peripheral blood of SLE patients with or without LN and healthy donors (HD).

Patients and Methods: SLE patients without LN, biopsy-proven LN and matched HD were analyzed. Active LN was defined as proteinuria>0.5 g/day or CrCl<60 ml/min/1.73 m² with active urinary sediment. Peripheral B cells were analyzed for direct PTX3 binding by flow cytometry using PTX3 labeled with cyanine 5 (Cy5) and phycoerythrin (PE).

Results: Initially, a flow cytometry based assay to identify PTX3⁺ B cells was developed by demonstrating simultaneous binding of PTX3-Cy5 and PTX3-PE. Specificity of B cells was validated by blocking experiments using unlabeled PTX3. We could identify circulating PTX3⁺ B-cells in HD and patients. Notably, LN patients showed a significantly diminished number of PTX3⁺ B cells (SLE vs. LN p = 0.033; HD vs. LN p = 0.008). This decrease was identified in naïve and memory B cell compartments (naïve: SLE vs. LN p = 0.028; HD vs. LN p = 0.0001; memory: SLE vs. LN p = 0.038, HD vs. LN p = 0.011).

Conclusions: Decreased PTX3⁺ B cells in LN within the naïve and memory compartment suggest their negative selection at early stages of B cell development potentially related to a decreased regulatory function. PTX3⁺ B cells could candidate for autoantigen-defined regulatory B cells as a striking abnormality of LN patients.

Long-term renal outcomes in multi-ethnic Southeast Asians with lupus nephritis: a retrospective cohort study

BACKGROUND

Renal involvement is common among Asians with systemic lupus erythematosus and long-term renal outcomes have been described in homogeneous Caucasian and East Asian populations with lupus nephritis, but data are scarce for other ethnicities.

AIM

To evaluate the incidence and risk factors for progressive chronic kidney disease (CKD) in multi-ethnic Southeast Asians with lupus nephritis.

METHODS

This is a single-centre retrospective cohort study of adults with biopsy-proven lupus nephritis diagnosed between May 2001 and May 2009. Demographic and clinical data were retrieved from electronic medical records. Patients were excluded if baseline comorbid, renal function or pharmacotherapy data were incomplete or if they default follow-up within 3 months from time of diagnosis. Primary outcome was progressive CKD, defined by end-stage renal disease or persistent doubling of serum creatinine or reduction in eGFR ≥50% for ≥3 months from baseline.

RESULTS

We studied 113 patients with newly diagnosed biopsy-proven lupus nephritis. Median age was 42 (interquartile range 29-52) years; the majority were Chinese (76%; Malay 13% and others 11%) and female (81%). Two-thirds had International Society of Nephrology and Renal Pathology Society Class III or IV nephritis; serum creatinine was 86 (67-125) μmol/L with heavy proteinuria (6.3 (2.5-12.2) g/g creatinine). Median follow-up was 110 (83-142) months. Remission (partial and complete) occurred in 96% at 3.1 (1.6-5.2) months after diagnosis. Among patients who achieved remission, 56% had disease relapse at 19.0 (6.0-40.2) months after remission. Patients with progressive CKD (n = 13, 11%) had lower baseline CKD Epidemiology Collaboration estimated glomerular filtration rate (37.3 (16.5-82.0) vs 79.4 (57.5-101.0) mL/min/1.73 m² , P = 0.03) and higher chronicity index (5 (3-6) vs 3 (2-3), P = 0.04) than those who did not. Remission, early remission within 6 months, complete remission and non-relapse were less frequently associated with progressive CKD (P < 0.01).

CONCLUSION

Multi-ethnic Southeast Asians with biopsy-proven lupus nephritis had high remission rates and low incidence of progressive CKD. Progressive CKD was associated with poorer baseline renal function, higher histological chronicity index, failure to achieve remission and occurrence of relapse.

Economic Evaluation of Lupus Nephritis in the Systemic Lupus International Collaborating Clinics Inception Cohort Using a Multistate Model Approach

OBJECTIVE

Little is known about the long-term costs of lupus nephritis (LN). The costs were compared between patients with and without LN using multistate modeling.

METHODS

Patients from 32 centers in 11 countries were enrolled in the Systemic Lupus International Collaborating Clinics inception cohort within 15 months of diagnosis and provided annual data on renal function, hospitalizations, medications, dialysis, and selected procedures. LN was diagnosed by renal biopsy or the American College of Rheumatology classification criteria. Renal function was assessed annually using the estimated glomerular filtration rate (GFR) or estimated proteinuria. A multistate model was used to predict 10-year cumulative costs by multiplying annual costs associated with each renal state by the expected state duration.

RESULTS

A total of 1,545 patients participated; 89.3% were women, the mean ± age at diagnosis was 35.2 ± 13.4 years, 49% were white, and the mean followup duration was 6.3 ± 3.3 years. LN developed in 39.4% of these patients by the end of followup. Ten-year cumulative costs were greater in those with LN and an estimated glomerular filtration rate (GFR) <30 ml/minute ($310,579 2015 Canadian dollars versus $19,987 if no LN and estimated GFR >60 ml/minute) or with LN and estimated proteinuria >3 gm/day ($84,040 versus $20,499 if no LN and estimated proteinuria <0.25 gm/day).

CONCLUSION

Patients with estimated GFR <30 ml/minute incurred 10-year costs 15-fold higher than those with normal estimated GFR. By estimating the expected duration in each renal state and incorporating associated annual costs, disease severity at presentation can be used to anticipate future health care costs. This is critical knowledge for cost-effectiveness evaluations of novel therapies.

The current role for clinical and renal histological findings as predictor for outcome in Australian patients with lupus nephritis

Objectives To investigate the current demographic, clinical and histological characteristics of patients with lupus nephritis (LN) in Western Australia (WA) with regards to their predictive value for patient and renal outcome. Methods Retrospective study of adult systemic lupus erythematosus (SLE) patients with a first renal biopsy demonstrating LN between 1997 and 2017 at a metropolitan tertiary hospital in WA. Clinical data were collected at baseline and last follow-up with renal biopsy findings classified by International Society of Nephrology (ISN) criteria. Annual incidence rates (AIRs)/100,000, Kaplan-Meyer curves and Cox regression hazard ratio for independent predictors for patient and renal survival were applied. Results The AIR was 3.3, 3.1 and 0.4 for Asian ( n = 29), Indigenous Australian (IA) ( n = 11) and Caucasian ( n = 43) patients, respectively ( p < 0.01). There was no significant subgroup difference regarding ISN class (proliferative 66%, membranous 19%, mesangial 15%), levels of proteinuria (median PCR 300 mg/mmol) or frequency of raised creatinine (31%), anti-dsDNA antibody (89%) or hypocomplementaemia (88%). Treatment included corticosteroids (91%), cyclophosphamide (30%), mycophenolate (67%) and antihypertensive drugs (67%). Five- (81%) and 10-year (70%) survival was lower for IAs than for Caucasians and Asians (95% each at both time points) ( p = 0.016). Five- and 10-year renal survival (endpoint renal replacement therapy (RRT)) was 86% and 64% for IA vs 100% for Asian, 100% and 96% for Caucasian patients ( p = 0.02). IA background was the only independent predictor for poor patient survival and together with male gender also for renal survival. Only 25% of all patients remained free of any organ damage with non-renal damage observed in 53% of survivors. Conclusions LN incidence in WA was 0.75/100,000 with the lowest rate observed in Caucasians. While Asian patients have the same favourable outlook as Caucasians, the outcome is much bleaker for IA patients. Other clinical and histological findings did not predict outcomes, and importantly more than half of all surviving patients accrued non-renal damage.

Evaluating duration of response to treatment in systemic lupus erythematosus clinical trials

Objective

To evaluate response duration and identify predictors of transitioning into and out of the response state in patients with SLE receiving standard of care (SoC) in 52-week clinical trials.

Methods

A multistate model (MSM) allowing for bidirectional transitions between response and non-response states was fit to data on 759 patients with SLE with active disease randomised to SoC. The probability of being in response at 52 weeks, average duration of response (sojourn time) and mean total time in response for SLE Responder Index (SRI-4, SRI-5, SRI-6) and BILAG-based Composite Lupus Assessment (BICLA) were estimated. Predictors of attainment and loss of SRI-5 response were also assessed.

Results

The MSM estimated probability of being in response at 52 weeks ranged from 42% (SRI-6) to 61% (SRI-4). Mean duration of response ranged from 20.4 weeks (BICLA) to 31.5 weeks (SRI-4). Mean total time in response was 16.4–24.8 weeks. Baseline characteristics predictive of shorter SRI-5 response duration were African descent (p=0.005), longer history of disease (p=0.03), higher anti-dsDNA antibody titres (p=0.039), lower lymphocyte count (p=0.008) and lower haemoglobin (p=0.006). Younger age (p<0.001) and higher protein/creatinine ratio (p<0.001) were associated with higher likelihood of achieving SRI-5 but also shorter response duration.

Conclusion

Factors associated with disease severity were more predictive of shorter response duration than of 52-week response status. Analysing landmark response rates and response duration using MSM may be a more powerful way to distinguish effective investigational treatments from background SoC, although this remains to be evaluated in future trials.

Changing patterns in clinical-histological presentation and renal outcome over the last five decades in a cohort of 499 patients with lupus nephritis

OBJECTIVES

To evaluate changes in demographic, clinical and histological presentation, and prognosis of lupus nephritis (LN) over time.

PATIENTS AND METHODS

We studied a multicentre cohort of 499 patients diagnosed with LN from 1970 to 2016. The 46-year follow-up was subdivided into three periods (P): P1 1970-1985, P2 1986-2001 and P3 2002-2016, and patients accordingly grouped based on the year of LN diagnosis. Predictors of patient and renal survival were investigated by univariate and multivariate proportional hazards Cox regression analyses. Survival curves were compared using the log-rank test.

RESULTS

A progressive increase in patient age at the time of LN diagnosis (p<0.0001) and a longer time between systemic lupus erythematosus onset and LN occurrence (p<0.0001) was observed from 1970 to 2016. During the same period, the frequency of renal insufficiency at the time of LN presentation progressively decreased (p<0.0001) and that of isolated urinary abnormalities increased (p<0.0001). No changes in histological class and activity index were observed, while chronicity index significantly decreased from 1970 to 2016 (p=0.023). Survival without end-stage renal disease (ESRD) was 87% in P1, 94% in P2% and 99% in P3 at 10 years, 80% in P1 and 90% in P2 at 20 years (p=0.0019). At multivariate analysis, male gender, arterial hypertension, absence of maintenance immunosuppressive therapy, increased serum creatinine, and high activity and chronicity index were independent predictors of ESRD.

CONCLUSIONS

Clinical presentation of LN has become less severe in the last years, leading to a better long-term renal survival.

Kidney Transplant Recipients With Rheumatic Diseases: Epidemiological Data From the Polish Transplant Registries 1998-2015

Chronic kidney disease (CKD) is a common complication of rheumatic disorders. We analyzed the incidence of different rheumatic conditions as a primary diagnosis of end-stage renal disease (ESRD) in kidney transplant recipients in Poland. Data were received from the national waiting list for organ transplantation (Poltransplant) registries. Primary diagnosis leading to ESRD were analyzed in 15,984 patients who received kidney transplants between 1998 and 2015. There was no information about primary diagnosis in 4981 cases (31%) and in 1482 cases (9%) the diagnosis was described as unknown. Rheumatic diseases were specified in 566 (5.14%) kidney transplant recipients: lupus erythematosus, (systemic lupus erythematous nephritis) in 211 (1.92%), vasculitis in 176 (1.60%), amyloidosis AA in 82 (0.75%), hemolytic uremic syndrome in 59 (0.54%), secondary glomerulonephritis in 24 (0.22%), scleroderma in 9 (0.08%), rheumatoid arthritis in 4 (0.04%) and Sjögren syndrome in 1 (0.01%). Graft survival at 1 and 5 years were significantly better in the nonrheumatic versus rheumatic group (90 vs 87% and 76 vs 72% respectively, P = .04). Recipient survival at 5 years was significantly better in the nonrheumatic versus the rheumatic group (88 vs 84%, P = .02). Our study showed that systemic lupus erythematosus and systemic vasculitides are the major rheumatic causes of ESRD in the Polish population. Long-term graft and recipient survival were significantly better in the nonrheumatic versus the rheumatic group in the Poltransplant cohort.

Alternative Design and Analytical Techniques for Longitudinal Rheumatology Studies: Improved Understanding of Outcomes

Longitudinal cohort designs (with three or more measurement occasions) are invaluable to investigate between- and within-individual variation in outcomes. However, traditional longitudinal designs require a lengthy implementation and data collection period and impose a substantial burden on participants and investigators. We discuss alternative longitudinal designs, including planned missing data designs and retrospective cohort studies with secondary data, which require a shorter period for data accrual and reduce participant burden while maintaining statistical power. We also discuss analysis strategies to maximize data use and produce unbiased estimates of treatment effectiveness, including models for recurrent or multistate events and time-varying covariates.

Correlated multistate models for multiple processes: an application to renal disease progression in systemic lupus erythematosus

Bidirectional changes over time in the estimated glomerular filtration rate and in urine protein content are of interest for the treatment and management of patients with lupus nephritis. Although these processes may be modelled by separate multistate models, the processes are likely to be correlated within patients. Motivated by the lupus nephritis application, we develop a new multistate modelling framework where subject-specific random effects are introduced to account for the correlations both between the processes and within patients over time. Models are fitted by using bespoke code in standard statistical software. A variety of forms for the random effects are introduced and evaluated by using the data from the Systemic Lupus International Collaborating Clinics.

Early proteinuria response: a valid real-life situation predictor of long-term lupus renal outcome in an ethnically diverse group with severe biopsy-proven nephritis?

Objective

Two recent important lupus nephritis trials reported that proteinuria was a good predictor of renal outcome in Caucasians, but data on real-life situation, other races and severe nephritis are lacking to substantiate this finding as a simple test to guide clinical practice. The aim of this study was to validate proteinuria as a predictor of long-term renal outcome in real-life situation in a racially diverse group of patients with severe nephritis.

Methods

Proteinuria, serum creatinine (SCr) and urine red blood cells were assessed at baseline and after 3, 6 and 12 months, as early predictors of long-term renal outcome (SCr <1.5 mg/dL at 7 years), in 94 patients with biopsy-proven lupus nephritis. The parameter performance and cut-off values were computed by receiver operating characteristic curves. Kaplan-Meier curves were used to validate the parameter.

Results

A proteinuria <0.8 g/24 hours at 12 months was the best single predictor of long-term renal outcome (sensitivity 90%, specificity 78%, positive predictive value 67%, negative predictive value (NPV) 94% and area under the curve 0.86; p<0.001). Addition of other variables to proteinuria such as SCr and haematuria at 12 months did not improve its performance. The proteinuria cut-off value of 0.8 g/24 hours at 12 months was a good predictor of 7-year renal survival (years free of dialysis) for patients with pure membranous (p=0.005) and proliferative nephritis (p=0.043), as well as black (p=0.002) and white race (p=0.001), anti-dsDNA positive (p=0.001) and anti-dsDNA negative (p=0.04) and male (p=0.028) and female (p=0.003) patients.

Conclusion

We provided novel evidence that, in a real-life situation, proteinuria at 12 months of follow-up was the single best predictor of renal outcome at 7 years for an ethnically diverse group of patients with severe nephritis and a valid parameter for distinct histological classes, races, genders and anti-dsDNA profiles. The remarkably high NPV obtained reinforces its recommendation as the ideal predictor for clinical practice, since it is of low cost, easy to interpret, non-invasive and widely available.

Assessing type I error and power of multistate Markov models for panel data-A simulation study

Ordinal outcomes collected at multiple follow-up visits are common in clinical trials. Sometimes, one visit is chosen for the primary analysis and the scale is dichotomized amounting to loss of information. Multistate Markov models describe how a process moves between states over time. Here, simulation studies are performed to investigate the type I error and power characteristics of multistate Markov models for panel data with limited non-adjacent state transitions. The results suggest that the multistate Markov models preserve the type I error and adequate power is achieved with modest sample sizes for panel data with limited non-adjacent state transitions.