Mycophenolate mofetil withdrawal in patients with systemic lupus erythematosus: a multicentre, open-label, randomised controlled trial

BACKGROUND

Mycophenolate mofetil is an immunosuppressant commonly used to treat systemic lupus erythematosus (SLE) and lupus nephritis. It is a known teratogen associated with significant toxicities, including an increased risk of infections and malignancies. Mycophenolate mofetil withdrawal is desirable once disease quiescence is reached, but the timing of when to do so and whether it provides a benefit has not been well-studied. We aimed to determine the effects of mycophenolate mofetil withdrawal on the risk of clinically significant disease reactivation in patients with quiescent SLE on long-term mycophenolate mofetil therapy.

METHODS

This multicenter, open-label, randomised trial was conducted in 19 centres in the USA. Eligible patients were aged between 18 and 70 years old, met the American College of Rheumatology (ACR) 1997 SLE criteria, and had a clinical SLEDAI score of less than 4 at screening. Mycophenolate mofetil therapy was required to be stable or decreasing for 2 years or more if initiated for renal indications, or for 1 year or more for non-renal indications. Participants were randomly allocated in a 1:1 ratio to a withdrawal group, who tapered off mycophenolate mofetil over 12 weeks, or a maintenance group who maintained their baseline dose (1-3g per day) for 60 weeks. Adaptive random allocation ensured groups were balanced for study site, renal versus non-renal disease, and baseline mycophenolate mofetil dose (≥2 g per day vs <2 g per day). Clinically significant disease reactivation by week 60 following random allocation, requiring increased doses or new immunosuppressive therapy was the primary endpoint, in the modified intention-to-treat population (all randomly allocated participants who began study-provided mycophenolate mofetil). Non-inferiority was evaluated using an estimation-based approach. The trial was registered at ClinicalTrials.gov (NCT01946880) and is completed.

FINDINGS

Between Nov 6, 2013, and April 27, 2018, 123 participants were screened, of whom 102 were randomly allocated to the maintenance group (n=50) or the withdrawal group (n=52). Of the 100 participants included in the modified intention-to-treat analysis (49 maintenance, 51 withdrawal), 84 (84%) were women, 16 (16%) were men, 40 (40%) were White, 41 (41%) were Black, and 76 (76%) had a history of lupus nephritis. The average age was 42 (SD 12·7). By week 60, nine (18%) of 51 participants in the withdrawal group had clinically significant disease reactivation, compared to five (10%) of 49 participants in the maintenance group. The risk of clinically significant disease reactivation was 11% (95% CI 5-24) in the maintenance group and 18% (10-32) in the withdrawal group. The estimated increase in the risk of clinically significant disease reactivation with mycophenolate mofetil withdrawal was 7% (one-sided upper 85% confidence limit 15%). Similar rates of adverse events were observed in the maintenance group (45 [90%] of 50 participants) and the withdrawal group (46 [88%] of 52 participants). Infections were more frequent in the mycophenolate mofetil maintenance group (32 [64%]) compared with the withdrawal group (24 [46%]).

INTERPRETATIONS

Mycophenolate mofetil withdrawal is not significantly inferior to mycophenolate mofetil maintenance. Estimates for the rates of disease reactivation and increases in risk with withdrawal can assist clinicians in making informed decisions on withdrawing mycophenolate mofetil in patients with stable SLE.

FUNDING

The National Institute of Allergy and Infectious Diseases and the National Institute of Arthritis and Musculoskeletal and Skin Diseases.

Associations between CD70 methylation of T cell DNA and age in adults with systemic lupus erythematosus and population controls: The Michigan Lupus Epidemiology & Surveillance (MILES) Program

BACKGROUND

Environmental factors can influence epigenetic regulation, including DNA methylation, potentially contributing to systemic lupus erythematosus (SLE) development and progression. We compared methylation of the B cell costimulatory CD70 gene, in persons with lupus and controls, and characterized associations with age.

RESULTS

In 297 adults with SLE and 92 controls from the Michigan Lupus Epidemiology and Surveillance (MILES) Cohort, average CD70 methylation of CD4+ T cell DNA across 10 CpG sites based on pyrosequencing of the promoter region was higher for persons with SLE compared to controls, accounting for covariates [β = 2.3, p = 0.011]. Using Infinium MethylationEPIC array data at 18 CD70-annoted loci (CD4+ and CD8+ T cell DNA), sites within the promoter region tended to be hypomethylated in SLE, while those within the gene region were hypermethylated. In SLE but not controls, age was significantly associated with pyrosequencing-based CD70 methylation: for every year increase in age, methylation increased by 0.14 percentage points in SLE, accounting for covariates. Also within SLE, CD70 methylation approached a significantly higher level in Black persons compared to White persons (β = 1.8, p = 0.051).

CONCLUSIONS

We describe altered CD70 methylation patterns in T lymphocyte subsets in adults with SLE relative to controls, and report associations particular to SLE between methylation of this immune-relevant gene and both age and race, possibly a consequence of "weathering" or accelerated aging which may have implications for SLE pathogenesis and potential intervention strategies.

Cost-related prescription non-adherence and patient-reported outcomes in systemic lupus erythematosus: The Michigan Lupus Epidemiology & Surveillance program

OBJECTIVES

Medication access and adherence play key roles in determining patient outcomes. We investigated whether cost-related non-adherence (CRNA) to prescription medications was associated with worse patient-reported outcomes in a population-based systemic lupus erythematosus (SLE) cohort.

METHODS

Sociodemographic and prescription data were collected by structured interviews in 2014-2015 from patients meeting SLE criteria in the established Michigan Lupus Epidemiology & Surveillance (MILES) Cohort. We examined the associations between CRNA and potential confounders such as sociodemographics and health insurance coverage, and outcome measures of SLE activity and damage using multivariable linear regression.

RESULTS

462 SLE participants completed the study visit: 430 (93.1%) female, 208 (45%) Black, and mean age 53.3 years. 100 (21.6%) participants with SLE reported CRNA in the preceding 12 months. After adjusting for covariates, CRNA was associated with both higher levels of current SLE disease activity [SLAQ: β coeff 2.7 (95% CI 1.3, 4.1), p < 0.001] and damage [LDIQ β coeff 1.4 (95% CI 0.5, 2.4), p = 0.003]. Race, health insurance status, and fulfilling Fibromyalgia (FM) Survey Criteria were independently associated with both higher (worse) SLAQ and LDIQ scores; female sex was further associated with higher SLAQ scores.

CONCLUSION

Patients with SLE who reported CRNA in the previous 12 months had significantly worse self-reported current disease activity and damage scores compared to those not reporting CRNA. Raising awareness and addressing barriers or concerns related to financial implications and accessibility issues in care plans may help to improve these outcomes.

Activation of a Latent Epitope Causing Differential Binding of Antineutrophil Cytoplasmic Antibodies to Proteinase 3

OBJECTIVE

Proteinase 3 (PR3) is the major antigen for antineutrophil cytoplasmic antibodies (ANCAs) in the systemic autoimmune vasculitis, granulomatosis with polyangiitis (GPA). PR3-targeting ANCAs (PR3-ANCAs) recognize different epitopes on PR3. This study was undertaken to study the effect of mutations on PR3 antigenicity.

METHODS

The recombinant PR3 variants, iPR3 (clinically used to detect PR3-ANCAs) and iHm5 (containing 3 point mutations in epitopes 1 and 5 generated for epitope mapping studies) immunoassays and serum samples from patients enrolled in ANCA-associated vasculitis (AAV) trials were used to screen for differential PR3-ANCA binding. A patient-derived monoclonal ANCA 518 (moANCA518) that selectively binds to iHm5 within the mutation-free epitope 3 and is distant from the point mutations of iHm5 was used as a gauge for remote epitope activation. Selective binding was determined using inhibition experiments.

RESULTS

Rather than reduced binding of PR3-ANCAs to iHm5, we found substantially increased binding of the majority of PR3-ANCAs to iHm5 compared to iPR3. This differential binding of PR3-ANCA to iHm5 is similar to the selective moANCA518 binding to iHm5. Binding of iPR3 to monoclonal antibody MCPR3-2 also induced recognition by moANCA518.

CONCLUSION

The preferential binding of PR3-ANCAs from patients, such as the selective binding of moANCA518 to iHm5, is conferred by increased antigenicity of epitope 3 on iHm5. This can also be induced on iPR3 when captured by monoclonal antibody MCPR2. This previously unrecognized characteristic of PR3-ANCA interactions with its target antigen has implications for studying antibody-mediated autoimmune diseases, understanding variable performance characteristics of immunoassays, and design of potential novel treatment approaches.

Glucocorticoid-induced osteoporosis in premenopausal women: management for the rheumatologist

PURPOSE OF REVIEW

This review seeks to summarize the literature relevant to the treatment of glucocorticoid-induced osteoporosis in premenopausal women; an issue commonly encountered by rheumatologists and yet lacking good clinical practice guidelines.

RECENT FINDINGS

Although most of the relevant literature on osteoporosis includes postmenopausal women only, data from both randomized controlled trials and case reports suggest bisphosphonates can be an effective and well tolerated treatment for premenopausal patients. Data for other medications to treat premenopausal osteoporosis is less robust.

SUMMARY

The use of bisphosphonates in young women may be safer than initially thought and should likely be used for the treatment of glucocorticoid-induced osteoporosis in rheumatology clinics. Further research is needed to continue to understand long-term risk.

Hypomethylation of miR-17-92 cluster in lupus T cells and no significant role for genetic factors in the lupus-associated DNA methylation signature

OBJECTIVES

Lupus T cells demonstrate aberrant DNA methylation patterns dominated by hypomethylation of interferon-regulated genes. The objective of this study was to identify additional lupus-associated DNA methylation changes and determine the genetic contribution to epigenetic changes characteristic of lupus.

METHODS

Genome-wide DNA methylation was assessed in naïve CD4+ T cells from 74 patients with lupus and 74 age-matched, sex-matched and race-matched healthy controls. We applied a trend deviation analysis approach, comparing methylation data in our cohort with over 16 500 samples. Methylation quantitative trait loci (meQTL) analysis was performed by integrating methylation profiles with genome-wide genotyping data.

RESULTS

In addition to the previously reported epigenetic signature in interferon-regulated genes, we observed hypomethylation in the promoter region of the miR-17-92 cluster in patients with lupus. Members of this microRNA cluster play an important role in regulating T cell proliferation and differentiation. Expression of two microRNAs in this cluster, miR-19b1 and miR-18a, showed a significant positive correlation with lupus disease activity. Among miR-18a target genes, TNFAIP3, which encodes a negative regulator of nuclear factor kappa B, was downregulated in lupus CD4+ T cells. MeQTL identified in lupus patients showed overlap with genetic risk loci for lupus, including CFB and IRF7. The lupus risk allele in IRF7 (rs1131665) was associated with significant IRF7 hypomethylation. However, <1% of differentially methylated CpG sites in patients with lupus were associated with an meQTL, suggesting minimal genetic contribution to lupus-associated epigenotypes.

CONCLUSION

The lupus defining epigenetic signature, characterised by robust hypomethylation of interferon-regulated genes, does not appear to be determined by genetic factors. Hypomethylation of the miR-17-92 cluster that plays an important role in T cell activation is a novel epigenetic locus for lupus.

Advances in the clinical use of hydroxychloroquine levels

PURPOSE OF REVIEW

This review summarizes the recent literature exploring hydroxychloroquine levels and their relationship with disease activity and risk of toxicity.

RECENT FINDINGS

There is no clear correlation between weight-based dosing of hydroxychloroquine and the resulting blood levels of the medication. Recent studies have shown that increased hydroxychloroquine levels are associated with lower lupus disease activity and likely also increased risk of medication toxicity.

SUMMARY

Mounting evidence supports use of hydroxychloroquine levels in clinical practice to document adherence and ensure safety.

Incidence rates of systemic lupus erythematosus in the USA: estimates from a meta-analysis of the Centers for Disease Control and Prevention national lupus registries

Objective

To estimate the annual incidence rate of SLE in the USA.

Methods

A meta-analysis used sex/race/ethnicity-specific data spanning 2002–2009 from the Centers for Disease Control and Prevention network of four population-based state registries to estimate the incidence rates. SLE was defined as fulfilling the 1997 revised American College of Rheumatology classification criteria. Given heterogeneity across sites, a random effects model was employed. Applying sex/race/ethnicity-stratified rates, including data from the Indian Health Service registry, to the 2018 US Census population generated estimates of newly diagnosed SLE cases.

Results

The pooled incidence rate per 100 000 person-years was 5.1 (95% CI 4.6 to 5.6), higher in females than in males (8.7 vs 1.2), and highest among black females (15.9), followed by Asian/Pacific Islander (7.6), Hispanic (6.8) and white (5.7) females. Male incidence was highest in black males (2.4), followed by Hispanic (0.9), white (0.8) and Asian/Pacific Islander (0.4) males. The American Indian/Alaska Native population had the second highest race-specific SLE estimates for females (10.4 per 100 000) and highest for males (3.8 per 100 000). In 2018, an estimated 14 263 persons (95% CI 11 563 to 17 735) were newly diagnosed with SLE in the USA.

Conclusions

A network of population-based SLE registries provided estimates of SLE incidence rates and numbers diagnosed in the USA.

Prevalence of Systemic Lupus Erythematosus in the United States: Estimates From a Meta-Analysis of the Centers for Disease Control and Prevention National Lupus Registries

OBJECTIVE

Epidemiologic data on systemic lupus erythematosus (SLE) are limited, particularly for racial/ethnic subpopulations in the US. This meta-analysis leveraged data from the Centers for Disease Control and Prevention (CDC) National Lupus Registry network of population-based SLE registries to estimate the overall prevalence of SLE in the US.

METHODS

The CDC National Lupus Registry network includes 4 registries from unique states and a fifth registry from the Indian Health Service. All registries defined cases of SLE according to the American College of Rheumatology (ACR) 1997 revised classification criteria for SLE. Case findings spanned either 2002-2004 or 2007-2009. Given the heterogeneity across sites, a random-effects model was used to calculate the pooled prevalence of SLE. An estimate of the number of SLE cases in the US was generated by applying sex/race-stratified estimates to the 2018 US Census population.

RESULTS

In total, 5,417 cases were identified as fulfilling the ACR SLE classification criteria. The pooled prevalence of SLE from the 4 state-specific registries was 72.8 per 100,000 person-years (95% confidence interval [95% CI] 65.3-81.0). The prevalence estimate was 9 times higher among females than among males (128.7 versus 14.6 per 100,000), and highest among Black females (230.9 per 100,000), followed by Hispanic females (120.7 per 100,000), White females (84.7 per 100,000), and Asian/Pacific Islander females (84.4 per 100,000). Among males, the prevalence of SLE was highest in Black males (26.7 per 100,000), followed by Hispanic males (18.0 per 100,000), Asian/Pacific Islander males (11.2 per 100,000), and White males (8.9 per 100,000). The American Indian/Alaska Native population had the highest race-specific SLE estimates, both among females (270.6 per 100,000) and among males (53.8 per 100,000). In 2018, an estimated 204,295 individuals (95% CI 160,902-261,725) in the US fulfilled the ACR classification criteria for SLE.

CONCLUSION

A coordinated network of population-based SLE registries provides more accurate estimates of the prevalence of SLE and the numbers of individuals affected with SLE in the US in 2018.

The use of mycophenolate mofetil area under the curve

PURPOSE OF REVIEW

Although mycophenolate mofetil (MMF) has been used successfully to treat a myriad of autoimmune diseases, its complex pharmacokinetics make it difficult to determine the true drug exposure for an individual patient. This review summarizes the body of literature focused on the gold standard measurement of the area under the curve (AUC) of mycophenolic acid (MPA), the active metabolite of MMF.

RECENT FINDINGS

Fixed dosing of MMF leads to highly variable drug exposure. Retrospective series have reported improved clinical outcomes when a minimum AUC value from 0 to 12 h (AUC0-12h) ≥30 mg h/l is achieved. MPA levels are affected by various drug interactions, hypoalbuminemia, and renal insufficiency and the measurement of free rather than total MPA levels is prudent in some situations. A limited number of studies employing prospective dose adjustment of MMF based on AUC0-12h measurements have yielded mixed results.

SUMMARY

Given the wide range of MPA AUC encountered in autoimmune diseases, dose adjustments of MMF based on AUC rather than fixed dosing of MMF should be considered in both clinical practice and clinical trials. Limited sampling strategies have been proposed to improve clinical feasibility of measurements, but a standard is yet to be defined.

A longitudinal and transancestral analysis of DNA methylation patterns and disease activity in lupus patients

Epigenetic dysregulation is implicated in the pathogenesis of lupus. We performed a longitudinal analysis to assess changes in DNA methylation in lupus neutrophils over 4 years of follow-up and across disease activity levels using 229 patient samples. We demonstrate that DNA methylation profiles in lupus are partly determined by ancestry-associated genetic variations and are highly stable over time. DNA methylation levels in 2 CpG sites correlated significantly with changes in lupus disease activity. Progressive demethylation in SNX18 was observed with increasing disease activity in African American patients. Importantly, demethylation of a CpG site located within GALNT18 was associated with the development of active lupus nephritis. Differentially methylated genes between African American and European American lupus patients include type I IFN–response genes such as IRF7 and IFI44, and genes related to the NF-κB pathway. TREML4, which plays a vital role in TLR signaling, was hypomethylated in African American patients and demonstrated a strong cis–methylation quantitative trait loci (cis-meQTL) effect among 8855 cis-meQTL associations identified in our study.

A genome-wide DNA methylation and genotyping approach in neutrophils from lupus patients identifies methylation changes that occur with time and as disease activity changes.

Anti-Neutrophil Extracellular Trap Antibodies and Impaired Neutrophil Extracellular Trap Degradation in Antiphospholipid Syndrome

OBJECTIVE

The release of neutrophil extracellular traps (NETs) by hyperactive neutrophils has recently been recognized to play an important role in antiphospholipid syndrome (APS). This study was undertaken to evaluate autoantibodies targeting NETs in patients with primary APS, and to determine their potential functions and clinical associations.

METHODS

We measured global anti-NET activity in 76 patients with primary APS, 23 patients with systemic lupus erythematosus without antiphospholipid antibodies (aPL), 11 patients with a history of unprovoked venous thrombosis without aPL, and 44 healthy controls. The ability of APS sera to degrade NETs was also assessed.

RESULTS

We found markedly elevated levels of anti-NET IgG and IgM in patients with primary APS compared with healthy controls (for IgG, mean ± SD optical density 0.55 ± 0.34 versus 0.33 ± 0.17; for IgM, mean ± SD optical density 0.76 ± 0.51 versus 0.26 ± 0.23). This anti-NET activity did not correlate with levels of traditional aPL and was relatively stable over time. Mechanistically, anti-NET antibodies (especially of the IgG isotype) impaired the ability of patient sera to degrade NETs (r = 0.4, P = 0.003). Levels of anti-NET IgM inversely correlated with complement C4 (r = 0.4, P = 0.019). Clinically, anti-NET antibodies associated with certain APS clinical manifestations, and in particular recurrent venous thrombosis (odds ratio 4.3; P = 0.002). Interestingly, anti-NET antibody levels also appeared to be associated with unprovoked venous thrombosis in the general population (for IgM, mean ± SD optical density 0.67 ± 0.34 versus 0.26 ± 0.23).

CONCLUSION

Our data indicate high levels of anti-NET antibodies in patients with primary APS, which may impair NET clearance and activate the complement cascade. These findings may ultimately enable more effective risk stratification.

Dietary Omega Polyunsaturated Fatty Acid Intake and Patient-Reported Outcomes in Systemic Lupus Erythematosus: The Michigan Lupus Epidemiology and Surveillance Program

OBJECTIVE

To examine associations between dietary intake of omega-3 (n-3; generally antiinflammatory) and omega-6 (n-6; generally proinflammatory) fatty acids and patient-reported outcomes in systemic lupus erythematosus (SLE).

METHODS

This study was based on the population-based Michigan Lupus Epidemiology and Surveillance cohort. Estimates of n-3 and n-6 intake were derived from Diet History Questionnaire II items (past year with portion size version). Patient-reported outcomes included self-reported lupus activity (Systemic Lupus Activity Questionnaire [SLAQ]). Multivariable regression, adjusted for age, sex, race, and body mass index, was used to assess associations between absolute intake of n-3 and n-6, as well as the n-6:n-3 ratio, and patient-reported outcomes.

RESULTS

Among 456 SLE cases, 425 (93.2%) were female, 207 (45.4%) were African American, and the mean ± SD age was 52.9 ± 12.3 years. Controlling for potential confounders, the average SLAQ score was significantly higher by 0.3 points (95% confidence interval [95% CI] 0.1, 0.6; P = 0.013) with each unit increase of the n-6:n-3 ratio. Both lupus activity and Patient-Reported Outcomes Measurement Information System (PROMIS) sleep disturbance scores were lower with each 1-gram/1,000 kcal increase of n-3 fatty acids (SLAQ regression coefficient β = -0.8 [95% CI -1.6, 0.0]; P = 0.055; PROMIS sleep β = -1.1 [95% CI -2.0, -0.2]; P = 0.017). Higher n-3 intakes were nonsignificantly associated with lower levels of depressive symptoms and comorbid fibromyalgia, and with higher quality of life, whereas results for the n6:n3 ratio trended in the opposite direction.

CONCLUSION

This population-based study suggests that higher dietary intake of n-3 fatty acids and lower n-6:n-3 ratios are favorably associated with patient-reported outcomes in SLE, particularly self-reported lupus activity and sleep quality.

Access and cost-related non-adherence to prescription medications among lupus cases and controls: the Michigan Lupus Epidemiology & Surveillance (MILES) Program

BACKGROUND

Medication access and adherence are important determinants of health outcomes. We investigated factors associated with access and cost-related non-adherence to prescriptions in a population-based cohort of systemic lupus erythematosus (SLE) patients and controls.

METHODS

Detailed sociodemographic and prescription data were collected by structured interview in 2014-2015 from participants in the Michigan Lupus Epidemiology & Surveillance (MILES) Cohort. We compared access between cases and frequency-matched controls and examined associated factors in separate multivariable logistic regression models.

RESULTS

654 participants (462 SLE cases, 192 controls) completed the baseline visit; 584 (89%) were female, 285 (44%) black, and mean age was 53 years. SLE cases and controls reported similar frequencies of being unable to access prescribed medications (12.1% vs 9.4%, respectively; p=NS). SLE patients were twice as likely as controls to report cost-related prescription non-adherence in the preceding 12 months to save money (21.7% vs 10.4%; p=0.001), but also more likely to ask their doctor for lower cost alternatives (23.8% vs 15.6%, p=0.02). Disparities were found in association with income, race and health insurance status, but main findings persisted after adjusting for these and other variables in multivariable models.

CONCLUSION

SLE patients were more likely than controls from the general population to report cost-related prescription non-adherence, including skipping doses, taking less medicine and delaying filling prescriptions, yet less than 1 in 4 patients asked providers for lower cost medications. Consideration of medication costs in patient decision-making could provide a meaningful avenue for improving access and adherence to medications.

West Nile encephalitis mimicking neuropsychiatric lupus in a patient with systemic lupus erythematosus

A man in his 70s with known systemic lupus erythematosus (SLE) was admitted with confusion, worsening proteinuria and cutaneous vasculitis despite adherence to his home immunosuppressive regimen. Admission laboratories were consistent with active lupus. Despite treatment with pulse-dose glucocorticoids and intravenous immunoglobulin, he developed worsening mental status and meningeal signs. Investigations revealed cerebrospinal fluid (CSF) neutrophilic and plasmacytic pleocytosis and negative cultures. Empiric treatment for SLE flare with potential neuropsychiatric involvement was continued while workup for altered mental status was ongoing. Ultimately, West Nile encephalitis was diagnosed by CSF serologies, and steroids were tapered. Altered mental status in a patient with SLE has a broad differential, and primary neuropsychiatric SLE should be considered only after exclusion of secondary causes. Although evidence of end-organ SLE activity usually lends support to a neuropsychiatric SLE diagnosis, in this case, serological and clinical evidence of SLE activity may have been triggered by acute viral infection.

Safety and Efficacy of Belimumab Plus Standard Therapy for Up to Thirteen Years in Patients With Systemic Lupus Erythematosus

Objective

To investigate the long‐term safety and efficacy of intravenous (IV) belimumab plus standard of care (SOC) therapy for systemic lupus erythematosus (SLE) in patients with active, autoantibody‐positive SLE.

Methods

The study was designed as a multicenter, open‐label, continuation study of IV belimumab given every 4 weeks in conjunction with SOC therapy in patients with SLE who completed a phase II, double‐blind study. Adverse events (AEs) and laboratory data were monitored from the first belimumab dose (in either study) until 24 weeks after the final dose. Efficacy assessments included SLE Responder Index (SRI) and flare index scores (each assessed at 16‐week intervals) and glucocorticoid use (assessed at 4‐week intervals).

Results

Of the 476 patients in the parent study, 298 (62.6%) entered the continuation study, of whom 96 (32.2%) remained in the study. Patients received belimumab for up to 13 years (median duration of exposure 3,334.0 days [range 260–4,332 days], total belimumab exposure 2,294 patient‐years, median number of infusions 115.5 [range 7–155]). The percentage of patients with AEs each year remained stable or decreased. Normal serum IgG levels were maintained in the majority of patients over the study, and the rate of infections remained stable. The percentage of patients who achieved an SRI response increased from 32.8% (year 1) to 75.6% of those remaining on treatment at year 12. The glucocorticoid dose was decreased in patients who had been receiving >7.5 mg/day at baseline.

Conclusion

This study is the longest to date to assess belimumab treatment in patients with SLE in clinical trials. Belimumab was well tolerated with no new safety concerns, and efficacy was maintained in patients who continued the study. For patients who initially exhibited a satisfactory response to belimumab, the treatment continues to be well tolerated and provides long‐term disease control.

Multicriteria decision analysis process to develop new classification criteria for systemic lupus erythematosus

European League Against Rheumatism and are jointly supporting multiphase development of systemic lupus erythematosus (SLE) classification criteria based on weighted criteria and a continuous probability scale. Prior steps included item generation, item reduction and hierarchical organisation of candidate criteria using an evidence-based approach. Our objectives were to determine relative weights using multicriteria decision analysis (MCDA) and to set a provisional threshold score for SLE classification. An SLE Expert Panel (8 European, 9 North American) submitted 164 real, unique cases with a wide range of SLE probability in a standardised format. Using the candidate criteria, experts scored and rank-ordered 20 representative cases. At an in-person meeting, experts reviewed inter-rater reliability of scoring, further refined criteria definitions and participated in an MCDA exercise. Based on expert consensus decisions on pairwise comparisons of criteria, 1000minds software calculated criteria weights and rank-ordered the remaining 144 cases based on their additive scores. The score of the lowest-ranked case for which complete expert consensus was achieved defined the provisional threshold classification score. Inter-rater reliability of scoring cases with the candidate criteria was good. MCDA involved 74 pairwise decisions and was repeated for the arthritis and mucocutaneous domains when the initial ranking of some cases did not match expert opinion. After criteria weights and additive scores were recalculated once, experts reached consensus for SLE classification for all cases scoring>83. Using an iterative process, the candidate criteria definitions were refined, preliminary weights were calculated and a provisional threshold score for SLE classification was determined.

The devil's in the dosing: severe drug-induced liver injury in a hydroxychloroquine-naive patient with subacute cutaneous lupus erythematosus and porphyria cutanea tarda

A 29-year-old woman with a 1.5 year history of photosensitive skin lesions on her hands presented with a malar rash, bullous lesions on her hands, and was diagnosed with subacute lupus erythematosus after serologies revealed a positive antinuclear antibody test (1:2560), and antibodies to Ro/SSA and dsDNA. Hydroxychloroquine (400 mg/day) was prescribed and the patient developed severe drug-induced liver injury. Biopsy of her bullous skin lesions was consistent with porphyria cutanea tarda, as were her serological and urinary exams. She was successfully treated with therapeutic phlebotomy. This case identifies porphyria cutanea tarda as an important differential diagnosis for the rheumatologist to consider when evaluating patients with bullous skin lesions. Hydroxychloroquine in lower doses is an effective treatment for porphyria cutanea tarda; at doses used to treat systemic lupus erythematosus and subacute cutaneous lupus, there is a potentially life-threatening complication of hepatotoxicity.

The ratio of erythrocyte sedimentation rate to C-reactive protein is useful in distinguishing infection from flare in systemic lupus erythematosus patients presenting with fever

Background Both C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) can be elevated in systemic lupus erythematosus (SLE) flare and infection, and are therefore of limited utility for distinguishing between the two conditions in febrile SLE patients. Methods A medical records review of hospitalizations (1997-2006) of SLE patients in the Michigan Lupus Cohort was performed. Eligible hospitalizations were those in which patients presented with a temperature of >100.3°F or with subjective fevers as a presenting complaint at admission. Detailed demographic, clinical, and laboratory data were collected. Multivariable logistic regression was used to examine the associations between ESR and CRP and the outcome of flare vs infection, adjusted for confounders. Results Among 557 SLE patients screened, there were 53 eligible hospitalizations (28 flares and 25 infections). Each unit increase in the ratio of ESR:CRP was associated with a 17% increase in the odds of fever being attributable to SLE flare compared to infection (OR 1.17, 95% CI 1.04, 1.31; p = 0.009), when adjusted for white blood cell count, SLE duration, sex, race, and age. ESR and CRP were not individually associated with flare vs infection when modeled with their ratio. Conclusions The ratio of ESR:CRP may provide diagnostic value beyond individual ESR and CRP levels in distinguishing flare vs infection in SLE patients presenting with fever.

The Utility of Urinalysis in Determining the Risk of Renal Relapse in ANCA-Associated Vasculitis

BACKGROUND AND OBJECTIVES

The significance of persistent hematuria or proteinuria in patients with ANCA-associated vasculitis who are otherwise in clinical remission is unclear.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A post hoc analysis was conducted using participants enrolled in two randomized, placebo-controlled clinical trials who had active GN due to ANCA-associated vasculitis, had positive ANCA, and achieved remission by month 6. Dipstick and microscopic urinalyses were performed at each visit. Persistent hematuria or proteinuria for at least 6 months and the cumulative duration of hematuria were examined. Renal relapse was defined as new or worsening red blood cell casts and/or worsening kidney function according to the Birmingham Vasculitis Activity Score for Granulomatosis with Polyangiitis.

RESULTS

There were 149 patients included in this study: 42% had persistent hematuria, and 43% had persistent proteinuria beyond 6 months. Persistent hematuria was associated with a significantly higher risk of relapse, even after adjusting for potential confounders (subdistribution hazard ratio, 3.99; 95% confidence interval, 1.20 to 13.25; P=0.02); persistent proteinuria was not associated with renal relapse (subdistribution hazard ratio, 1.44; 95% confidence interval, 0.47 to 4.42; P=0.53). Furthermore, greater cumulative duration of hematuria was significantly associated with a higher risk of renal relapse (adjusted subdistribution hazard ratio, 1.08 per each month; 95% confidence interval, 1.03 to 1.12; P<0.01). The median time to renal relapse was 22 months.

CONCLUSIONS

In patients with ANCA-associated vasculitis and kidney involvement who achieve remission after induction therapy, the presence of persistent hematuria, but not proteinuria, is a significant predictor of future renal relapse.

Epigenetic Reprogramming in Naive CD4+ T Cells Favoring T Cell Activation and Non-Th1 Effector T Cell Immune Response as an Early Event in Lupus Flares

OBJECTIVE

Systemic lupus erythematosus (SLE) is a relapsing autoimmune disease that affects multiple organ systems. T cells play an important role in the pathogenesis of lupus; however, early T cell events triggering disease flares are incompletely understood. This study was undertaken to examine DNA methylation in naive CD4+ T cells from lupus patients to determine if epigenetic remodeling in CD4+ T cells is an early event in lupus flares.

METHODS

A total of 74 lupus patients with an SLE Disease Activity Index score of 0-18 were included. Naive CD4+ T cells were isolated from peripheral blood samples, and DNA was extracted for genome-wide methylation assessment. RNA was also extracted from a subset of patients to determine the relationship between epigenetic changes and transcription activity using RNA sequencing and microRNA arrays.

RESULTS

We demonstrated that naive CD4+ T cells in lupus undergo an epigenetic proinflammatory shift, implicating effector T cell responses in lupus flare. This epigenetic landscape change occurs without changes in expression of the corresponding genes, poises naive CD4+ T cells for Th2, Th17, and follicular helper T cell immune responses, and opposes inhibitory transforming growth factor β signaling. Bioinformatics analyses indicate that the epigenetic modulator EZH2 might play an important role in shifting the epigenetic landscape, with increased disease activity in lupus naive CD4+ T cells. Further, the expression of microRNA-26a, which is sensitive to glucose availability and targets EZH2, was negatively correlated with disease activity in lupus patients.

CONCLUSION

An epigenetic landscape shift in naive CD4+ T cells that favors T cell activation and non-Th1 immune responses predates transcription activity and correlates with lupus activity. A role for EZH2 dysregulation in triggering lupus flares warrants further investigation.

X Chromosome Dose and Sex Bias in Autoimmune Diseases: Increased Prevalence of 47,XXX in Systemic Lupus Erythematosus and Sjögren's Syndrome

OBJECTIVE

More than 80% of autoimmune disease predominantly affects females, but the mechanism for this female bias is poorly understood. We suspected that an X chromosome dose effect accounts for this, and we undertook this study to test our hypothesis that trisomy X (47,XXX; occurring in ∼1 in 1,000 live female births) would be increased in patients with female-predominant diseases (systemic lupus erythematosus [SLE], primary Sjögren's syndrome [SS], primary biliary cirrhosis, and rheumatoid arthritis [RA]) compared to patients with diseases without female predominance (sarcoidosis) and compared to controls.

METHODS

All subjects in this study were female. We identified subjects with 47,XXX using aggregate data from single-nucleotide polymorphism arrays, and, when possible, we confirmed the presence of 47,XXX using fluorescence in situ hybridization or quantitative polymerase chain reaction.

RESULTS

We found 47,XXX in 7 of 2,826 SLE patients and in 3 of 1,033 SS patients, but in only 2 of 7,074 controls (odds ratio in the SLE and primary SS groups 8.78 [95% confidence interval 1.67-86.79], P = 0.003 and odds ratio 10.29 [95% confidence interval 1.18-123.47], P = 0.02, respectively). One in 404 women with SLE and 1 in 344 women with SS had 47,XXX. There was an excess of 47,XXX among SLE and SS patients.

CONCLUSION

The estimated prevalence of SLE and SS in women with 47,XXX was ∼2.5 and ∼2.9 times higher, respectively, than that in women with 46,XX and ∼25 and ∼41 times higher, respectively, than that in men with 46,XY. No statistically significant increase of 47,XXX was observed in other female-biased diseases (primary biliary cirrhosis or RA), supporting the idea of multiple pathways to sex bias in autoimmunity.

Immunoglobulin (Ig)M antibodies to proteinase 3 in granulomatosis with polyangiitis and microscopic polyangiitis

Anti-neutrophil cytoplasmic antibodies (ANCA) appear to play an important role in the pathogenesis of ANCA-associated vasculitis (AAV). However, ANCA alone are not sufficient to generate disease, and some evidence suggests that infectious triggers may serve as inciting events for AAV disease activity. Antibodies of the immunoglobulin (Ig)M isotype often serve as markers of recent infection, and IgM ANCA have been identified previously in patients with AAV, although the frequency and clinical relevance of IgM ANCA is not well established. We sought to characterize IgM ANCA more clearly by creating a novel enzyme-linked immunosorbent assay (ELISA) for IgM antibodies to proteinase 3 [IgM proteinase 3 (PR3)-ANCA], which we applied to two large, clinically well-characterized trial cohorts of patients with granulomatosis with polyangiitis and microscopic polyangiitis. In the first cohort, IgM PR3-ANCA occurred with a frequency of 15·0%, and were associated with a higher degree of disease severity and a trend towards a higher rate of alveolar haemorrhage (29·6 versus 15·7%, P = 0·10). Analysis of follow-up samples in this cohort showed that the presence of IgM PR3-ANCA was transient, but could recur. In the second cohort, IgM PR3-ANCA occurred with a frequency of 41·1%, and were also associated with a higher degree of disease severity. A higher rate of alveolar haemorrhage was observed among those with IgM PR3-ANCA (45·3 versus 15·8%; P < 0·001). The association of transient IgM PR3-ANCA with an acute respiratory manifestation of AAV suggests a possible link between an infectious trigger and AAV disease activity.

Endothelial progenitor dysfunction associates with a type I interferon signature in primary antiphospholipid syndrome

OBJECTIVES

Patients with antiphospholipid syndrome (APS) are at risk for subclinical endothelial injury, as well as accelerated atherosclerosis. In the related disease systemic lupus erythematosus, there is a well-established defect in circulating endothelial progenitors, which leads to an accrual of endothelial damage over time. This defect has been at least partially attributed to exaggerated expression of type I interferons (IFNs). We sought to determine whether these pathways are important in APS.

METHODS

We studied 68 patients with primary APS. Endothelial progenitors were assessed by flow cytometry and functional assay. Type I IFN activity was determined by a well-accepted bioassay, while peripheral blood mononuclear cells were scored for expression of IFN-responsive genes.

RESULTS

Endothelial progenitors from patients with APS demonstrated a marked defect in the ability to differentiate into endothelial cells, a phenotype which could be mimicked by treating control progenitors with APS sera. Elevated type I IFN activity was detected in the circulation of patients with APS (a finding that was then replicated in an independent cohort). While IgG depletion from APS sera did not rescue endothelial progenitor function, the dysfunction was successfully reversed by a type I IFN receptor-neutralising antibody.

CONCLUSIONS

We describe, for the first time to our knowledge, an IFN signature in primary APS and show that this promotes impaired endothelial progenitor function. This work opens the door to novel approaches that may mitigate vascular damage in APS, such as anti-IFN drugs.

Utility and Associated Risk of Pulmonary Embolism Computed Tomography Scans in the Michigan Lupus Cohort

OBJECTIVE

Systemic lupus erythematosus patients are frequently evaluated for chest pain and may have multiple pulmonary embolism (PE) computed tomography (CT) scans. This study was undertaken to determine the incidence of pulmonary embolism in the University of Michigan Lupus Cohort patients who have undergone PE CT scans and to estimate the associated increased risk of breast and lung cancer from radiation exposure.

METHODS

We reviewed records of patients in the University of Michigan Lupus Cohort (n = 854) and determined the number and outcome of PE CT scans. Radimetrics software was used to perform individualized calculations of radiation dose to the lung and breast of each patient. We used this dose information, the patient's age at the time of scan, and risks according to the Biological Effects of Ionizing Radiation, report VII, to estimate the increased incidence risks of breast and lung cancer.

RESULTS

A total of 182 of 856 patients (21%) underwent 357 PE CT scans. The overall rate of positivity was 7.5%. For patients undergoing their first through third scans, the rate of positivity for PE was 8.8%, whereas patients undergoing their fourth through tenth scans had 1.6% positivity. The highest increase in incidence risk was 0.87% for breast and 0.62% for lung.

CONCLUSION

Patients with multiple previous PE CT scans had lower likelihood of a positive result on subsequent scans and higher risks of malignancy. The magnitude of risk should not discourage performance of PE CT when clinically indicated.

CD70 methylation of a regulatory region increases with age in lupus patients

T cell DNA hypomethylation contributes to systemic lupus erythematosus (SLE), although the mechanisms are poorly understood. Previous work has shown that CD70, a B cell costimulatory ligand, is hypomethylated and overexpressed in lupus T cells, and that the overexpression leads to increased B cell costimulation and concomitant immunoglobulin overproduction. Recent evidence suggests that the methylation status of certain genes may characterize ‘epigenetic aging’, and that epigenetic age may be a stronger predictor than chronological age of health outcomes. CD70 has not been examined in this context, therefore we sought to characterize the methylation status of CD70 in lupus patients across age. CD4+ T cells were obtained from peripheral blood of 89 consecutive lupus patients enrolled in a population-based cohort. CD70 methylation of a regulatory region was assessed by bisulfite conversion and pyrosequencing. Mean methylation across 10 sites known to be hypomethylated in lupus patients was measured and correlated with age. CD70 methylation increased linearly with increasing age of lupus patients. These results suggest that CD70 may be involved in “epigenetic aging”, and that the increased hypomethylation of CD70 in younger patients may contribute to the earlier onset and increased severity of disease. Further studies of aging effects on methylation of immune genes involved in lupus may improve our understanding of the variability in susceptibility and onset of the disease.

Systemic lupus erythematosus complicated by diffuse alveolar haemorrhage: risk factors, therapy and survival

Objectives

While diffuse alveolar haemorrhage (DAH) is recognised as a life-threatening complication of systemic lupus erythematosus (SLE), little is known about its risk factors and response to treatment. We describe 22 cases of DAH in a US lupus cohort of approximately 1000 patients, and compare them to 66 controls from the same outpatient cohort.

Methods

We captured variables pertaining to diagnoses of SLE and secondary antiphospholipid syndrome (APS), and analysed them by univariate testing. Those variables with p values <0.05 were then further considered in a multivariate model. Kaplan-Meier curves were constructed for each group, and survival was analysed by Log-rank test.

Results

Of the 22 patients with DAH, 59% were diagnosed with DAH within 5 years of lupus diagnosis. By univariate testing, several manifestations of SLE and APS were more common in patients with DAH, including history of thrombocytopenia, cardiac valve disease, low C3, leucopenia, neuropsychiatric features, haemolysis, arterial thrombosis, lupus anticoagulant, secondary APS and low C4. On multivariate analysis, history of thrombocytopenia and low C3 were maintained as independent risk factors. Importantly, only two patients had platelet counts <50 000/µL at the time of the DAH episode, arguing that DAH was not simply a haemorrhagic complication of thrombocytopenia. All patients were treated with increased immunosuppression, including various combinations of corticosteroids, plasmapheresis, cyclophosphamide, rituximab and mycophenolate mofetil. Notably, all patients in the cohort survived their initial episode of DAH. While the patients with DAH did well in the short-term, their long-term survival was significantly worse than controls. Several of the deaths were attributable to thrombotic complications after recovering from DAH.

Conclusions

To the best of our knowledge, this is the largest case–control study of lupus DAH to date. History of thrombocytopenia was strongly predictive of DAH (OR ∼40). A number of APS manifestations correlated with DAH by univariate analysis, and deserve further consideration in larger studies.

DNA methylation patterns in naïve CD4+ T cells identify epigenetic susceptibility loci for malar rash and discoid rash in systemic lupus erythematosus

Objective

Systemic lupus erythematosus (SLE) is a complex autoimmune disease characterised by heterogeneous clinical manifestations, autoantibody production and epigenetic dysregulation in T cells. We sought to investigate the epigenetic contribution to the development of cutaneous manifestations in SLE.

Methods

We performed genome-wide DNA methylation analyses in patients with SLE stratified by a history of malar rash, discoid rash or neither cutaneous manifestation, and age, sex and ethnicity matched healthy controls. We characterised differentially methylated regions (DMRs) in naïve CD4+ T cells unique to each disease subset, and assessed functional relationships between DMRs using bioinformatic approaches.

Results

We identified 36 and 37 unique DMRs that contribute to the epigenetic susceptibility to malar rash and discoid rash, respectively. These DMRs were primarily localised to genes mediating cell proliferation and apoptosis. Hypomethylation of MIR886 and TRIM69, and hypermethylation of RNF39 were specific to patients with SLE with a history of malar rash. Hypomethylation of the cytoskeleton-related gene RHOJ was specific to patients with SLE with a history of discoid rash. In addition, discoid rash-specific hypomethylated DMRs were found in genes involved in antigen-processing and presentation such as TAP1 and PSMB8. Network analyses showed that DMRs in patients with SLE with but not without a history of cutaneous manifestations are associated with TAP-dependent processing and major histocompatibility-class I antigen cross-presentation (p=3.66×10⁻¹⁸ in malar rash, and 3.67×10⁻¹³ in discoid rash).

Conclusions

We characterised DNA methylation changes in naïve CD4+ T cells specific to malar rash and discoid rash in patients with SLE. These data suggest unique epigenetic susceptibility loci that predispose to or are associated with the development of cutaneous manifestations in SLE.

A highlight from the LUPUS 2014 meeting: eight great ideas

This review describes eight 'great ideas' regarding bench-to-bedside considerations in systemic lupus erythematosus (SLE) presented at the second international LUPUS meeting in Quebec, September 2014. The topics included: correcting the impaired clearance of apoptotic fragments; optimisation of clinical trial design: the PERFECT (Pre Evaluation Reducing Frighteningly Elevated Coverable Targets) study; lipidomics and metabolomics in SLE; importance of the inflammasome; identification and treatment of asymptomatic autoimmunity: prevention of SLE; combining low doses of hydroxychloroquine and quinacrine for long-term maintenance therapy of SLE; reducing emergency room visits and the critical relevance of the autoantigen.

Renal involvement in lupus is characterized by unique DNA methylation changes in naïve CD4+ T cells

Systemic lupus erythematosus is a multi-system disease characterized by wide-spread DNA methylation changes. To identify epigenetic susceptibility loci for lupus nephritis, genome-wide DNA methylation changes in naïve CD4+ T cells were compared between two sets of lupus patients with and without a history of renal involvement. A total of 56 lupus patients (28 with renal involvement and 28 without renal involvement), and 56 age-, sex-, and ethnicity-matched healthy controls were included in our study. We identified 191 CG sites and 121 genes that were only differentially methylated in lupus patients with but not without a history of renal involvement. The tyrosine kinase gene TNK2 involved in cell trafficking and tissue invasion, and the phosphatase gene DUSP5 which dephosphorylates and inhibits the ERK signaling pathway, were among the most hypomethylated. Independent of disease activity, renal involvement is characterized by more robust demethylation in interferon regulated genes differentially methylated in both sets of lupus patients with and without renal involvement (fold change 1.4, P = 0.0014). The type-I interferon master regulator gene IRF7 is only hypomethylated in lupus patients with renal involvement. IRF-7 is an upstream transcription factor that regulates several loci demethylated only with renal involvement such as CD80, HERC5, IFI44, IRF7, ISG15, ISG20, ITGAX, and PARP12 (P = 1.78 × 10(-6)). Among the CG sites only hypomethylated with renal involvement, CG10152449 in CHST12 has a sensitivity of 85.7% and a specificity of 64.3% for stratifying lupus patients for a history of renal involvement (P = 0.0029). Our data identified novel epigenetic susceptibility loci that are differentially methylated with renal involvement in lupus. These loci will help better understand lupus nephritis, and provide a proof of principle for the potential applicability of specific methylation changes as predictors for specific organ involvement in lupus.

Incidence and prevalence of systemic lupus erythematosus among Arab and Chaldean Americans in southeastern Michigan: the Michigan Lupus Epidemiology and Surveillance Program

OBJECTIVES

We assessed the burden of systemic lupus erythematosus (SLE) among Arab and Chaldean Americans residing in southeast Michigan.

METHODS

For those meeting SLE criteria from the Michigan Lupus Epidemiology and Surveillance Registry, we determined Arab or Chaldean ethnicity by links with demographic data from birth certificates and with a database of Arab and Chaldean names. We compared prevalence and incidence of SLE for Arab and Chaldean Americans with estimates for non-Arab and non-Chaldean American Whites and Blacks.

RESULTS

We classified 54 individuals with SLE as Arab and Chaldean Americans. The age-adjusted incidence and prevalence estimates for Arab and Chaldean Americans were 7.6 and 62.6 per 100 000, respectively. Arab and Chaldean Americans had a 2.1-fold excess SLE incidence compared with non-Arab and non-Chaldean American Whites. Arab and Chaldean American women had both significantly higher incidence rates (5.0-fold increase) and prevalence estimates (7.4-fold increase) than did Arab and Chaldean American men.

CONCLUSIONS

Recognizing that Arab and Chaldean Americans experience different disease burdens from Whites is a first step toward earlier diagnosis and designing targeted interventions. Better methods of assigning ethnicity would improve research in this population.

Increased usage of special educational services by children born to mothers with systemic lupus erythematosus and antiphospholipid antibodies

INTRODUCTION

Surveys of long-term health and developmental outcomes of children born to mothers with systemic lupus erythematosus (SLE) have suggested an increase in learning disabilities among these children. We performed this observational study to investigate the relationship between maternal autoantibodies and antiphospholipid antibody syndrome (APS) in maternal lupus patients and neurocognitive development among their offspring.

METHODS

SLE mothers with at least one live birth postlupus diagnosis were enrolled. Data on maternal medical/obstetric history and children's perinatal/medical history were collected by structured interview and medical record reviews. The primary outcome was requirement for special educational (SE) services, a proxy for developmental delays. Multiple logistic regression modelling was used to examine associations between APS and autoantibodies with SE usage, accounting for SLE disease severity and potential confounders.

RESULTS

Data on 38 mothers and 60 offspring were analysed: SE service usage was reported for 15 of 60 (25%) offspring. Maternal APS history was significantly associated with increased use of SE services among offspring, including after adjustment for lupus anticoagulant (LA) positivity and potential confounders (OR 5.5-9.4 for delays age ≥2; p<0.05). The presence of LA, but not other antiphospholipid antibodies, was also associated with increased SE services usage.

CONCLUSIONS

Maternal APS and LA were independently associated with increased usage of special educational services among offspring of women with SLE.

Population-based incidence and prevalence of systemic lupus erythematosus: the Michigan Lupus Epidemiology and Surveillance program

OBJECTIVE

To estimate the incidence and prevalence of systemic lupus erythematosus (SLE) in a sociodemographically diverse southeastern Michigan source population of 2.4 million people.

METHODS

SLE cases fulfilling the American College of Rheumatology classification criteria (primary case definition) or meeting rheumatologist-judged SLE criteria (secondary definition) and residing in Wayne or Washtenaw Counties during 2002-2004 were included. Case finding was performed from 6 source types, including hospitals and private specialists. Age-standardized rates were computed, and capture-recapture was performed to estimate underascertainment of cases.

RESULTS

The overall age-adjusted incidence and prevalence (ACR definition) per 100,000 persons were 5.5 (95% confidence interval [95% CI] 5.0-6.1) and 72.8 (95% CI 70.8-74.8). Among females, the incidence was 9.3 per 100,000 persons and the prevalence was 128.7 per 100,000 persons. Only 7 cases were estimated to have been missed by capture-recapture, adjustment for which did not materially affect the rates. SLE prevalence was 2.3-fold higher in black persons than in white persons, and 10-fold higher in females than in males. Among incident cases, the mean ± SD age at diagnosis was 39.3 ± 16.6 years. Black SLE patients had a higher proportion of renal disease and end-stage renal disease (ESRD) (40.5% and 15.3%, respectively) as compared to white SLE patients (18.8% and 4.5%, respectively). Black patients with renal disease were diagnosed as having SLE at younger age than white patients with renal disease (mean ± SD 34.4 ± 14.9 years versus 41.9 ± 21.3 years; P = 0.05).

CONCLUSION

SLE prevalence was higher than has been described in most other population-based studies and reached 1 in 537 among black female persons. There were substantial racial disparities in the burden of SLE, with black patients experiencing earlier age at diagnosis, >2-fold increases in SLE incidence and prevalence, and increased proportions of renal disease and progression to ESRD as compared to white patients.

Disease Control and Safety of Belimumab Plus Standard Therapy Over 7 Years in Patients with Systemic Lupus Erythematosus

Objective.

To evaluate the efficacy/safety of belimumab plus standard therapy in patients (n = 449) with active systemic lupus erythematosus (SLE) treated up to 7 years (n = 177 currently ongoing).

Methods.

Patients (n = 345) who completed a double-blind, placebo-controlled, 52-week study of belimumab 1, 4, or 10 mg/kg and 24-week extension of belimumab (placebo switched to 10 mg/kg; belimumab same dose or switched to 10 mg/kg) could receive belimumab 10 mg/kg in an open-label continuation study (n = 296). Disease activity was analyzed in patients with active SLE at baseline of the initial study. Biomarker and SLE medication changes were evaluated, and adverse events (AE) were monitored throughout the study.

Results.

Total belimumab exposure over 7 years (double-blind and open-label periods): 1746 patient-years. SLE Responder Index (SRI) response rates at Week 52 in autoantibody-positive patients: placebo, 29%; belimumab, 46% (p < 0.05). In the continuation study, 57% of auto-antibody-positive patients had an SRI response by Year 2 and 65% by Year 7; severe flares occurred in 19% with placebo and 17% with belimumab during the first year, with the annual rate declining to 2%–9% during years 2–7. Anti-dsDNA autoantibodies in patients positive for them at baseline had a progressive decline of 40%–60% from baseline over 2–7 years with belimumab. Corticosteroid use decreased over time with ≥ 50–55% reduction in median dose during years 5–7. Serious and overall annual AE rates, including infections, were generally stable or decreased during 7-year treatment.

Conclusion.

Disease control and safety profile were maintained in patients with active SLE taking belimumab plus standard therapy for up to 7 years. [ClinicalTrials.gov numbers: NCT00071487 and NCT00583362]

The peroxisome-proliferator activated receptor-γ agonist pioglitazone modulates aberrant T cell responses in systemic lupus erythematosus

PPAR-γ agonists can suppress autoimmune responses and renal inflammation in murine lupus but the mechanisms implicated in this process remain unclear. We tested the effect of the PPAR-γ agonist pioglitazone in human lupus and control PBMCs with regard to gene regulation and various functional assays. By Affymetrix microarray analysis, several T cell-related pathways were significantly highlighted in pathway analysis in lupus PBMCs. Transcriptional network analysis showed IFN-γ as an important regulatory node, with pioglitazone treatment inducing transcriptional repression of various genes implicated in T cell responses. Confirmation of these suppressive effects was observed specifically in purified CD4+ T cells. Pioglitazone downregulated lupus CD4+ T cell effector proliferation and activation, while it significantly increased proliferation and function of lupus T regulatory cells. We conclude that PPAR-γ agonists selectively modulate CD4+ T cell function in SLE supporting the concept that pioglitazone and related,-agents should be explored as potential therapies in this disease.

In utero azathioprine exposure and increased utilization of special educational services in children born to mothers with systemic lupus erythematosus

OBJECTIVE

Azathioprine (AZA) is recognized among immunosuppressive medications as relatively safe during pregnancy for women with systemic lupus erythematosus (SLE) requiring aggressive treatment. This pilot study aimed to determine whether SLE therapy during pregnancy was associated with developmental delays in offspring.

METHODS

This cohort study included SLE patients with at least one live birth postdiagnosis. Medical histories were obtained via interviews and chart review. Multiple logistic regression was used to examine associations between SLE therapy during pregnancy and maternal report of special educational (SE) requirements (as proxy for developmental delays) among offspring. Propensity scoring (incorporating corticosteroid use, lupus flare, and lupus nephritis) was used to account for disease severity.

RESULTS

Of 60 eligible offspring from 38 mothers, 15 required SE services, the most common indication for which was speech delay. Seven (54%) of the 13 children with in utero AZA exposure utilized SE services versus 8 (17%) of 47 nonexposed children (P < 0.01). After adjustment for pregnancy duration, small for gestational age, propensity score, maternal education level, and antiphospholipid antibody syndrome, AZA was significantly associated with SE utilization occurring from age 2 years onward (odds ratio 6.6, 95% confidence interval 1.0-43.3), and bordered on significance for utilization at any age or age <2 years.

CONCLUSION

AZA exposure during SLE pregnancy was independently associated with increased SE utilization in offspring, after controlling for confounders. Further research is indicated to fully characterize developmental outcomes among offspring with in utero AZA exposure. Vigilance and early interventions for suspected developmental delays among exposed offspring may be warranted.

Genome-wide DNA methylation study suggests epigenetic accessibility and transcriptional poising of interferon-regulated genes in naïve CD4+ T cells from lupus patients

Systemic lupus erythematosus is an autoimmune disease characterized by multi-system involvement and autoantibody production. Abnormal T cell DNA methylation and type-I interferon play an important role in the pathogenesis of lupus. We performed a genome-wide DNA methylation study in two independent sets of lupus patients and matched healthy controls to characterize the DNA methylome in naïve CD4+ T cells in lupus. DNA methylation was quantified for over 485,000 methylation sites across the genome, and differentially methylated sites between lupus patients and controls were identified and then independently replicated. Gene expression analysis was also performed from the same cells to investigate the relationship between the DNA methylation changes observed and mRNA expression levels. We identified and replicated 86 differentially methylated CG sites between patients and controls in 47 genes, with the majority being hypomethylated. We observed significant hypomethylation in interferon-regulated genes in naïve CD4+ T cells from lupus patients, including IFIT1, IFIT3, MX1, STAT1, IFI44L, USP18, TRIM22 and BST2, suggesting epigenetic transcriptional accessibility in these genetic loci. Indeed, the majority of the hypomethylated genes (21 out of 35 hypomethylated genes) are regulated by type I interferon. The hypomethylation in interferon-regulated genes was not related to lupus disease activity. Gene expression analysis showed overexpression of these genes in total but not naïve CD4+ T cells from lupus patients. Our data suggest epigenetic "poising" of interferon-regulated genes in lupus naïve CD4+ T cells, argue for a novel pathogenic implication for abnormal T cell DNA methylation in lupus, and suggest a mechanism for type-I interferon hyper-responsiveness in lupus T cells.

Overexpression of X-linked genes in T cells from women with lupus

Women develop lupus more frequently than men and the reason remains incompletely understood. Evidence that men with Klinefelter's Syndrome (XXY) develop lupus at approximately the same rate as women suggests that a second X chromosome contributes. However, since the second X is normally inactivated, how it predisposes to lupus is unclear. DNA methylation contributes to the silencing of one X chromosome in women, and CD4+ T cell DNA demethylation contributes to the development of lupus-like autoimmunity. This suggests that demethylation of genes on the inactive X may predispose women to lupus, and this hypothesis is supported by a report that CD40LG, an immune gene encoded on the X chromosome, demethylates and is overexpressed in T cells from women but not men with lupus. Overexpression of other immune genes on the inactive X may also predispose women to this disease. We therefore compared mRNA and miRNA expression profiles in experimentally demethylated T cells from women and men as well as in T cells from women and men with lupus. T cells from healthy men and women were treated with the DNA methyltransferase inhibitor 5-azacytidine, then X-linked mRNAs were surveyed with oligonucleotide arrays, and X-linked miRNA's surveyed with PCR arrays. CD40LG, CXCR3, OGT, miR-98, let-7f-2*, miR 188-3p, miR-421 and miR-503 were among the genes overexpressed in women relative to men. MiRNA target prediction analyses identified CBL, which downregulates T cell receptor signaling and is decreased in lupus T cells, as a gene targeted by miR-188-3p and miR-98. Transfection with miR-98 and miR-188-3p suppressed CBL expression. The same mRNA and miRNA transcripts were also demethylated and overexpressed in CD4+ T cells from women relative to men with active lupus. Together these results further support a role for X chromosome demethylation in the female predisposition to lupus.

Adjunctive GnRH-a treatment attenuates depletion of ovarian reserve associated with cyclophosphamide therapy in premenopausal SLE patients

BACKGROUND

We measured antimullerian hormone (AMH), a marker of ovarian reserve, in women with lupus treated with cyclophosphamide (CYC) (group I), CYC plus gonadotropin-releasing hormone agonist (GnRH-a) (group II) or neither (group III). We hypothesized that AMH would be diminished in women exposed to CYC versus women receiving adjunctive GnRH-a treatment or no CYC exposure.

METHODS

Forty-eight premenopausal lupus patients were retrospectively divided into three treatment groups: CYC alone (group I, n = 11), CYC + GnRH-a (group II, n = 10) and neither (group III, n = 27). Serum AMH levels between groups were compared using a nonparametric test (Wilcoxon rank-sum). Multiple linear regression adjusting for age was performed.

RESULTS

AMH (ng/mL) levels at the last collection were significantly lower in group I versus group III (mean ± SD: 0.18 ± 0.20 group I vs 1.33 ± 1.59 group III; p = 0.015), and versus group II (mean ± SD: 0.86 ± 1.06; p = 0.018). When centered on age 30 years, average AMH levels for group I, group II and group III were 0.20, 0.44 and 1.00, respectively. When adjusted for age, AMH between all groups was significantly different (p<0.0001).

CONCLUSION

Posttreatment AMH levels were significantly higher among patients receiving CYC + GnRH-a compared to CYC alone, suggesting that GnRH-a coadministration mitigates CYC-induced ovarian injury.

Effect of belimumab on vaccine antigen antibodies to influenza, pneumococcal, and tetanus vaccines in patients with systemic lupus erythematosus in the BLISS-76 trial

OBJECTIVE

In patients with systemic lupus erythematosus (SLE), evidence suggests that most vaccines (except live-virus vaccines) are safe, although antibody response may be reduced. This substudy from the phase III, randomized, double-blind, placebo-controlled BLISS-76 trial evaluated the effects of belimumab on preexisting antibody levels against pneumococcal, tetanus, and influenza antigens in patients with SLE.

METHODS

In BLISS-76, patients with autoantibody-positive, active SLE were treated with placebo or belimumab 1 or 10 mg/kg every 2 weeks for 28 days and every 28 days thereafter, plus standard SLE therapy, for 76 weeks. This analysis included a subset of patients who had received pneumococcal or tetanus vaccine within 5 years or influenza vaccine within 1 year of study participation. Antibodies to vaccine antigens were tested at baseline and Week 52, and percentage changes in antibody levels from baseline and proportions of patients maintaining levels at Week 52 were assessed. Antibody titers were also assessed in a small number of patients vaccinated during the study.

RESULTS

Consistent with preservation of the memory B cell compartment with belimumab treatment, the proportions of patients maintaining antibody responses to pneumococcal, tetanus, and influenza antigens were not reduced. In a small group receiving influenza vaccine on study, antibody responses were frequently lower with belimumab, although titer levels were > 1:10 in all patients treated with 10 mg/kg and in the majority treated with 1 mg/kg.

CONCLUSION

Treatment with belimumab did not affect the ability of patients with SLE to maintain antibody titers to previous pneumococcal, tetanus, and influenza immunizations. [ClinicalTrials.gov registration number NCT 00410384].

Type I interferons are associated with subclinical markers of cardiovascular disease in a cohort of systemic lupus erythematosus patients

BACKGROUND

Systemic lupus erythematosus (SLE) patients have a striking increase in cardiovascular (CV) comorbidity not fully explained by the Framingham risk score. Recent evidence from in vitro studies suggests that type I interferons (IFN) could promote premature CV disease (CVD) in SLE. We assessed the association of type I IFN signatures with functional and anatomical evidence of vascular damage, and with biomarkers of CV risk in a cohort of lupus patients without overt CVD.

METHODOLOGY/PRINCIPAL FINDINGS

Serum type I IFN activity (induction of five IFN-inducible genes; IFIGs) from 95 SLE patient and 38 controls was quantified by real-time PCR. Flow mediated dilatation (FMD) of the brachial artery and carotid intima media thickness (CIMT) were quantified by ultrasound, and coronary calcification by computed tomography. Serum vascular biomarkers were measured by ELISA. We evaluated the effect of type I IFNs on FMD, CIMT and coronary calcification by first applying principal components analysis to combine data from five IFIGs into summary components that could be simultaneously modeled. Three components were derived explaining 97.1% of the total IFIG variation. Multivariable linear regression was utilized to investigate the association between the three components and other covariates, with the outcomes of FMD and CIMT; zero-inflated Poisson regression was used for modeling of coronary calcification. After controlling for traditional CV risk factors, enhanced serum IFN activity was significantly associated with decreased endothelial function in SLE patients and controls (p<0.05 for component 3), increased CIMT among SLE patients (p<0.01 for components 1 and 2), and severity of coronary calcification among SLE patients (p<0.001 for component 3).

CONCLUSIONS

Type I IFNs are independently associated with atherosclerosis development in lupus patients without history of overt CVD and after controlling for Framingham risk factors. This study further supports the hypothesis that type I IFNs promote premature vascular damage in SLE.

Sex-specific differences in the relationship between genetic susceptibility, T cell DNA demethylation and lupus flare severity

Lupus is less common in men than women, and the reason is incompletely understood. Current evidence indicates that lupus flares when genetically predisposed individuals encounter environmental agents that trigger the disease, and that the environmental contribution is mediated at least in part by T cell DNA demethylation. We hypothesized that lupus disease activity is directly related to total genetic risk and inversely related to T cell DNA methylation levels in each patient. Since women are predisposed to lupus in part because of their second X chromosome, we also hypothesized that men would require a greater genetic risk, a greater degree of autosomal T cell DNA demethylation, or both, to achieve a lupus flare equal in severity to women. Genetic risk was determined by genotyping men and women with lupus across 32 confirmed lupus susceptibility loci. The methylation status of two autosomal genes known to demethylate in T cells in proportion to disease activity, KIR2DL4 (KIR) and PRF1, was measured by bisulfite sequencing. Lupus disease activity was determined by the SLEDAI. Interactions between genetic score, T cell DNA demethylation, and the SLEDAI score were compared between the men and women by regression analysis. Combining the degree of DNA demethylation with the genetic risk score for each patient demonstrated that the (genetic risk)/(DNA methylation) ratio increased directly with disease activity in both men and women with lupus. Importantly, men required a greater (genetic risk)/(DNA methylation) ratio to achieve a SLEDAI score equivalent to women (P = 0.010 for KIR and P = 0.0054 for PRF1). This difference was not explained by a difference in the genetic risk or T cell DNA demethylation alone, suggesting a genetic-epigenetic interaction. These results suggest that genetic risk and T cell DNA demethylation interact in lupus patients to influence the severity of lupus flares, and that men require a higher genetic risk and/or greater degree of T cell DNA demethylation to achieve a lupus flare equal in severity to women.

Changes in regional brain morphology in neuropsychiatric systemic lupus erythematosus

OBJECTIVE

Neuropsychiatric lupus (NPSLE) is a severe and potentially life-threatening condition, reported to occur in 25%-70% of patients with systemic lupus erythematosus (SLE). Brain imaging, especially magnetic resonance imaging, is frequently used to diagnose or exclude overt cerebral pathologies such as edema, hemorrhage, and central thrombosis. More advanced imaging techniques have been applied to demonstrate subtle changes in regional cerebral blood flow and brain structure. We investigated changes in regional gray-matter (GM) volume in SLE patients without neurological manifestations and NPSLE patients at an acute stage of the disease.

METHODS

Using high-resolution structural images and voxel-based morphometry (VBM), we investigated regional GM volume in 20 NPSLE patients (within 2 weeks of the acute manifestation), 18 SLE patients without neurologic and/or psychiatric manifestations, and 18 healthy controls.

RESULTS

VBM analyses revealed several regions of GM atrophy in various parts of the brain in NPSLE and SLE patients. GM atrophy was seen in both groups in the temporal and parietal lobes and was most pronounced in the posterior thalamus bilaterally. Both groups showed an increase in regional GM volume in the posterior parahippocampal gyrus.

CONCLUSION

Our data suggest that changes in regional brain morphology are present in acute NPSLE, but also in SLE (as compared to controls), which might be indicative of a subclinical neurodegenerative process. Further research is needed to investigate whether specific neuropsychiatric symptoms are related to these changes.

Assessment of health-related quality of life as an outcome measure in granulomatosis with polyangiitis (Wegener's)

OBJECTIVE

To assess a generic measure of health-related quality of life (HRQOL) as an outcome measure in granulomatosis with polyangiitis (Wegener's) (GPA).

METHODS

Subjects were participants in the Wegener's Granulomatosis Etanercept Trial (WGET) or the Vasculitis Clinical Research Consortium Longitudinal Study (VCRC-LS). HRQOL was assessed with the Short Form 36 (SF-36) health survey that includes physical and mental component summary scores (PCS and MCS, respectively). Disease activity was assessed with the Birmingham Vasculitis Activity Score for Wegener's Granulomatosis (BVAS/WG).

RESULTS

The data from 180 subjects in the WGET (median followup 2.3 years, mean number of visits 10) and 237 subjects in the VCRC-LS (median followup 2.0 years, mean number of visits 8) were analyzed. A 1 unit increase in the BVAS/WG corresponded to a 1.15 unit (95% confidence interval [95% CI] 1.02, 1.29) decrease for the PCS and a 0.93 (95% CI 0.78, 1.07) decrease for the MCS in the WGET, and to a 1.16 unit decrease for the PCS (95% CI 0.94, 1.39) and a 0.79 unit decrease for the MCS (95% CI 0.51, 1.39) in the VCRC-LS. In both arms of the WGET study, SF-36 measures improved rapidly during the first 6 weeks of treatment followed by gradual improvement among patients achieving sustained remission (0.5 improvement in PCS per 3 months), but worsened slightly (0.03 decrease in PCS every 3 months) among patients not achieving sustained remission (P = 0.005).

CONCLUSION

HRQOL, as measured by the SF-36, is reduced among patients with GPA. SF-36 measures are modestly associated with other disease outcomes and discriminate between disease states of importance in GPA.

Ovarian reserve diminished by oral cyclophosphamide therapy for granulomatosis with polyangiitis (Wegener's)

OBJECTIVE

Standard treatment for severe granulomatosis with polyangiitis (Wegener's) (GPA) is daily oral cyclophosphamide (CYC), a cytotoxic agent associated with ovarian failure. In this study, we assessed the rate of diminished ovarian reserve in women with GPA who received CYC versus methotrexate (MTX).

METHODS

Patients in the Wegener's Granulomatosis Etanercept Trial received either daily CYC or weekly MTX and were randomized to etanercept or placebo. For all women ages <50 years, plasma samples taken at baseline or early in the study were evaluated against samples taken later in the study to compare levels of anti-Müllerian hormone (AMH) and follicle-stimulating hormone (FSH), endocrine markers of remaining egg supply. Diminished ovarian reserve was defined as an AMH level of <1.0 ng/ml.

RESULTS

Of 42 women in this analysis (mean age 35 years), 24 had CYC exposure prior to enrollment and 28 received the drug during the study. At study entry, women with prior CYC exposure had significantly lower AMH, higher FSH, and a higher rate of early menstruation cessation. For women with normal baseline ovarian function, 6 of 8 who received CYC during the trial developed diminished ovarian reserve, compared to 0 of 4 who did not receive CYC (P < 0.05). Changes in AMH correlated inversely with cumulative CYC dose (P < 0.01), with a 0.74 ng/ml decline in AMH level for each 10 gm of CYC.

CONCLUSION

Daily oral CYC, even when administered for less than 6 months, causes diminished ovarian reserve, as indicated by low AMH levels. These data highlight the need for alternative treatments for GPA in women of childbearing age.

Solid malignancies among etanercept-treated patients with granulomatosis with polyangiitis (Wegener's): long-term followup of a multicenter longitudinal cohort

OBJECTIVE

An association between therapeutic inhibition of tumor necrosis factor (TNF) and solid malignancies was observed during the Wegener's Granulomatosis Etanercept Trial (WGET), which included 180 patients with granulomatosis with polyangiitis (Wegener's) (GPA). The present study was conducted to determine the malignancy risk beyond the time of exposure to study therapy.

METHODS

The occurrence and type of solid malignancies were ascertained using a standardized data form. Data collected included vital status, histologic findings, and therapeutic interventions. The Surveillance, Epidemiology, and End-Results database was used to estimate a standardized incidence rate (SIR) for solid malignancies.

RESULTS

Post-trial followup data were available for 153 patients (85% of the original cohort), with a median followup time of 43 months. Fifty percent of these patients had received etanercept. There were no differences in demographic characteristics between the etanercept and placebo groups. Thirteen new solid malignancies were detected, 8 in the etanercept group and 5 in the placebo group. Compared to the general population, the risk of solid malignancies in the etanercept group was increased (SIR 3.92 [95% confidence interval 1.69-7.72]), but was not different from the risk in the placebo group compared to the general population (SIR 2.89 [95% confidence interval 0.94-6.73]). All solid malignancies occurred in patients who had been exposed to cyclophosphamide. The overall duration of disease and a history of malignancy before trial enrollment were associated with the development of malignancy during post-trial followup.

CONCLUSION

The incidence of solid malignancy remained increased during long-term followup of the WGET cohort. However, this could not be attributed solely to etanercept exposure during the trial. Anti-TNF therapy with etanercept appears to further increase the risk of malignancy observed in patients with GPA treated with cytotoxic agents and should be avoided in these patients.

A model to predict cardiovascular events in patients with newly diagnosed Wegener's granulomatosis and microscopic polyangiitis

OBJECTIVE

To create a prognostic tool to quantify the 5-year cardiovascular (CV) risk in patients with newly diagnosed Wegener's granulomatosis (WG) and microscopic polyangiitis (MPA) without premorbid CV disease.

METHODS

We reviewed CV outcomes during the long-term followup of patients in the first 4 European Vasculitis Study Group (EUVAS) trials of WG and MPA. CV events were defined as CV death, stroke, myocardial infarction, coronary artery bypass graft, or percutaneous coronary intervention. Logistic regression was performed to create a model to predict the absolute risk of a CV event. The model was tested using the Wegener's Granulomatosis Etanercept Trial (WGET) cohort.

RESULTS

Seventy-four (13.8%) of 535 patients with 5 years of followup from the EUVAS trials had at least 1 CV event: 33 (11.7%) of 281 WG versus 41 (16.1%) of 254 MPA. The independent determinants of CV outcomes were older age (odds ratio [OR] 1.45, 95% confidence interval [95% CI] 1.11-1.90), diastolic hypertension (OR 1.97, 95% CI 0.98-3.95), and positive proteinase 3 (PR3) antineutrophil cytoplasmic antibody (ANCA) status (OR 0.39, 95% CI 0.20-0.74). The model was validated using the WGET cohort (area under the receiver operating characteristic curve of 0.80).

CONCLUSION

Within 5 years of diagnosis of WG or MPA, 14% of patients will have a CV event. We have constructed and validated a tool to quantify the risk of a CV event based on age, diastolic hypertension, and PR3 ANCA status in patients without prior CV disease. In patients with vasculitis, PR3 ANCA is associated with a reduced CV risk compared to myeloperoxidase ANCA or negative ANCA status.