The incidence and prevalence of systemic lupus erythematosus, 2002-2004: The Georgia Lupus Registry

Adverse Perinatal Outcomes Before and After Diagnosis with Systemic Lupus Erythematosus Among African American Women

OBJECTIVE

Women with systemic lupus erythematosus (SLE) may experience adverse perinatal outcomes in the years before an SLE diagnosis. Overall, there is limited research on perinatal outcomes among African American women with SLE.

METHODS

Women with SLE identified from the Georgia Lupus Registry and the Georgians Organized Against Lupus Cohort were linked with birth certificates by the Georgia Department of Public Health. Births were categorized into occurring more than 3 years before SLE diagnosis, 0-3 years before SLE diagnosis, 0-3 years after SLE diagnosis or more than 3 years after SLE diagnosis. Comparison births certificates to African American women in the same geographic area were obtained from the National Center for Health Statistics. We used log-risk models to compare the risk of preterm birth or small-for-gestational age among SLE births in each diagnosis timing category to the general population, adjusting for maternal age and education and parity.

RESULTS

Births to women with SLE were more likely to occur preterm 0-3 years before SLE diagnosis (risk ratio [RR]: 1.71, 95% confidence interval [CI]: 1.24, 2.35), 0-3 years after SLE diagnosis (RR: 2.29, 95% CI: 1.70, 3.09) and 3 or more years after diagnosis (RR: 2.83, 95% CI: 2.36, 3.38), but not 3 or more years before SLE diagnosis compared to the general population (RR: 1.03, 95% CI: 0.77, 1.38). Similar results were observed for small-for-gestational age births.

CONCLUSION

Our analysis, conducted among African American women, demonstrates an increased risk of adverse perinatal outcomes even before a clinical diagnosis of SLE.

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.

Anticipatory racism stress, smoking and disease activity: the Black women's experiences living with lupus (BeWELL) study

African American women with systemic lupus erythematosus (SLE) have worse disease outcomes compared to their White counterparts. Stressors associated with race may contribute to poorer health in this population through maladaptive behavioral pathways. This study investigated relationships between stress associated with anticipating racism, smoking, and SLE disease activity. Data were from 432 African American women with SLE in the Black Women's Experiences Living with Lupus (BeWELL) Study. Controlling for sociodemographic and health-related covariates, multivariable regression analyses revealed a significant association between anticipatory racism stress (ARS) and disease activity (p = 0.00, b = 1.13, 95% CI [0.43, 1.82]). A significant interaction between ARS and smoking also indicated that smoking exacerbated the effect of ARS on disease activity (p = 0.04, b = 1.95, CI = 0.04, 3.96). Test for evidence of smoking mediating the effect of ARS on disease activity were not statistically significant (z = 1.77, p = 0.08). Findings have implications for future SLE disparities research among African American women with SLE.

Role of Environment in Pediatric Rheumatic Diseases

Studying environmental risk factors for pediatric rheumatic diseases (PRD) is important because the identification of these factors may lead to strategies to prevent disease, and to new insights into pathogenesis and therapeutic targets. Compared with other chronic diseases, there are few environmental epidemiology studies in PRD. Although strong risk factors common to all PRDs have not been identified, some exposures including infection, smoke exposure, and ultraviolet radiation have been associated with several of them. High-technology studies, especially of microbiomics and metabolomics, are increasing and will likely lead to new understandings of the complex interplay between environment, genetics, and disease.

History of Proliferative Glomerulonephritis Predicts End Stage Kidney Disease in Pure Membranous Lupus Nephritis

OBJECTIVES

Pure membranous (class V) lupus nephritis (LN) is considered a less aggressive phenotype, but tissue fibrosis and chronic kidney disease may still develop. This study aimed to elucidate the prognostic value of a history of class switch in pure membranous LN.

METHODS

We included LN patients with at least two clinically indicated kidney biopsies. New onset of end stage kidney disease (ESKD) was defined as estimated glomerular filtration rate < 15 ml/min/1.73m2, initiation of dialysis, or kidney transplantation.

RESULTS

Among 220 patients (542 biopsies), 199 (90%) were female, and 118 (54%) were African American, 59 (27%) Caucasian, with median age of 28 years at the first kidney biopsy. Patients with pure class V in a first biopsy converted to proliferative LN in 41% of cases. Pure class V in a repeat biopsy was preceded by proliferative LN in 52%. Trajectory analysis of up to 4 repeat biopsies revealed that ISN class switch may happen at any time, even after multiple biopsies with the same class. New onset ESKD was observed within 2 years in 5/56 (9%) patients with pure class V in a repeat biopsy. All 5 patients had proliferative LN in the first biopsy (log rank p= 0.024).

CONCLUSIONS

The conversion from proliferative to membranous (and vice-versa) is frequent in SLE. It can occur at any time in the course of disease, limiting the prognostic value of the first biopsy. Evidence of prior proliferative LN is key as it is associated with higher risk of ESKD in non-proliferative LN.

Long-Term Outcome in Systemic Lupus Erythematosus; Knowledge from Population-Based Cohorts

Background: Accurate knowledge of outcomes in Systemic Lupus Erythematosus (SLE) is crucial to understanding the true burden of the disease. The main objective of this systematic review was to gather all population-based studies on mortality, end-stage renal disease (ESRD) and cancer in SLE. Method: We performed a systematic literature search in two electronic databases (MEDLINE and Embase) to identify all population-based articles on SLE and survival, mortality, ESRD and cancer. The SLE diagnosis had to be verified. We used the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines (PRISMA). Results: We included 40/1041 articles on mortality (27), ESRD (11) and cancer (3), of which six were defined as inception studies. In the total SLE cohort, the standardized mortality ratio ranged from 1.9 to 4.6. Cardiovascular disease was the most frequent cause of death in studies with follow-up times over 15 years. SLE progressed to ESRD in 5–11% of all SLE patients. There are no data supporting increased cancer incidence from population-based inception cohorts. Conclusion: There is a need for more population-based studies on outcomes of SLE, especially inception studies, with the use of control groups and follow-up times over 15 years.

The Th17/IL-17 Axis and Kidney Diseases, With Focus on Lupus Nephritis

Systemic lupus erythematosus (SLE) is a disease characterized by dysregulation and hyperreactivity of the immune response at various levels, including hyperactivation of effector cell subtypes, autoantibodies production, immune complex formation, and deposition in tissues. The consequences of hyperreactivity to the self are systemic and local inflammation and tissue damage in multiple organs. Lupus nephritis (LN) is one of the most worrying manifestations of SLE, and most patients have this involvement at some point in the course of the disease. Among the effector cells involved, the Th17, a subtype of T helper cells (CD4+), has shown significant hyperactivation and participates in kidney damage and many other organs. Th17 cells have IL-17A and IL-17F as main cytokines with receptors expressed in most renal cells, being involved in the activation of many proinflammatory and profibrotic pathways. The Th17/IL-17 axis promotes and maintains repetitive tissue damage and maladaptive repair; leading to fibrosis, loss of organ architecture and function. In the podocytes, the Th17/IL-17 axis effects include changes of the cytoskeleton with increased motility, decreased expression of health proteins, increased oxidative stress, and activation of the inflammasome and caspases resulting in podocytes apoptosis. In renal tubular epithelial cells, the Th17/IL-17 axis promotes the activation of profibrotic pathways such as increased TGF-β expression and epithelial-mesenchymal transition (EMT) with consequent increase of extracellular matrix proteins. In addition, the IL-17 promotes a proinflammatory environment by stimulating the synthesis of inflammatory cytokines by intrinsic renal cells and immune cells, and the synthesis of growth factors and chemokines, which together result in granulopoiesis/myelopoiesis, and further recruitment of immune cells to the kidney. The purpose of this work is to present the prognostic and immunopathologic role of the Th17/IL-17 axis in Kidney diseases, with a special focus on LN, including its exploration as a potential immunotherapeutic target in this complication.

Global epidemiology of systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune disease with protean manifestations that predominantly affects young women. Certain ethnic groups are more vulnerable than others to developing SLE and experience increased morbidity and mortality. Reports of the global incidence and prevalence of SLE vary widely, owing to inherent variation in population demographics, environmental exposures and socioeconomic factors. Differences in study design and case definitions also contribute to inconsistent reporting. Very little is known about the incidence of SLE in Africa and Australasia. Identifying and remediating such gaps in epidemiology is critical to understanding the global burden of SLE and improving patient outcomes. Mortality from SLE is still two to three times higher than that of the general population. Internationally, the frequent causes of death for patients with SLE include infection and cardiovascular disease. Even without new therapies, mortality can potentially be mitigated with enhanced quality of care. This Review focuses primarily on the past 5 years of global epidemiological studies and discusses the regional incidence and prevalence of SLE and top causes of mortality.

The Problem of Pain in Systemic Lupus Erythematosus: An Explication of the Role of Biopsychosocial Mechanisms

OBJECTIVE

To define biopsychosocial mechanisms of pain that go above and beyond disease activity and organ damage in systemic lupus erythematosus (SLE).

METHODS

We conducted a cross-sectional analysis of patient-reported data in a population-based registry of 766 people with SLE. Predictors of pain intensity and interference were examined using hierarchical linear regression. We built 2 main hierarchical regression models with pain intensity and interference as outcomes, both regressed on disease activity and organ damage. For each model, we sought to establish the relationship between pain outcomes and the primary exposures using sequential steps comprising the inclusion of each construct in 6 stages: demographic, socioeconomic, physical, psychological, behavioral, and social factors. We also conducted sensitivity analyses eliminating all overt aspects of pain in the disease activity measure and reestimated the models.

RESULTS

Disease activity and organ damage explained 32-33% of the variance in pain intensity and interference. Sociodemographic factors accounted for an additional 4-9% of variance in pain outcomes, whereas psychosocial/behavioral factors accounted for the final 4% of variance. In the sensitivity analyses, we found that disease activity and organ damage explained 25% of the variance in pain outcomes.

CONCLUSION

Disease activity only explained 33% of the variance in pain outcomes. However, there was an attenuation in these associations after accounting for psychosocial/behavioral factors, highlighting their roles in modifying the relationship between disease activity and pain. These findings suggest that multilevel interventions may be needed to tackle the negative effect of pain in SLE.

A multianalyte assay panel with cell-bound complement activation products demonstrates clinical utility in systemic lupus erythematosus

Objective

To evaluate the clinical utility of the multianalyte assay panel (MAP), commercially known as AVISE Lupus test (Exagen Inc.), in patients suspected of SLE.

Methods

A systematic review of medical records of ANA-positive patients with a positive (>0.1) or negative (<−0.1) MAP score was conducted when the MAP was ordered (T0), when the test results were reviewed (T1) and at a later time (T2, ≥8 months after T1). Confidence in the diagnosis of SLE and initiation of hydroxychloroquine (HCQ) were assessed.

Results

A total of 161 patient records from 12 centres were reviewed at T0 and T1. T2 occurred for 90 patients. At T0, low, moderate and high confidence in SLE diagnosis was reported for 58%, 30% and 12% patients, respectively. Confidence in SLE diagnosis increased for the MAP positive, while MAP negative made SLE less likely. Odds of higher confidence in SLE diagnosis increased by 1.74-fold for every unit of increase of the MAP score (p<0.001). Using the MAP-negative/anti-double-stranded DNA-negative patients as reference, the HR of assigning an International Classification of Diseases, Tenth Revision lupus code was 7.02-fold, 11.2-fold and 14.8-fold higher in the low tier-2, high tier-2 and tier-1 positive, respectively (p<0.001). The HR of initiating HCQ therapy after T0 was 2.90-fold, 4.22-fold and 3.98-fold higher, respectively (p<0.001).

Conclusion

The MAP helps increase the confidence in ruling-in and ruling-out SLE in patients suspected of the disease and informs on appropriate treatment decisions.

Pathways linking census tract typologies with subjective neighborhood disorder and depressive symptoms in the Black Women's Experiences Living with Lupus (BeWELL) Study

Depression is a common comorbidity among Black women with systemic lupus erythematosus (SLE), an understudied autoimmune disease characterized by major racial and gender inequities. Research is needed that examines how area-level factors influence risk of depression in this population. Latent profile analysis revealed four neighborhood typologies among metropolitan Atlanta, Georgia census tracts that participants (n=438) in the Black Women's Experiences Living with Lupus (BeWELL) Study were living in: Integrated/High-SES, Moderately Segregated/Mid-SES, Highly Segregated/Mid-SES, and Highly Segregated/Low-SES. Structural equation models indicated that highly segregated census tracts were associated with the greatest levels of depression via increased subjective assessments of neighborhood disorder. Policies that invest in segregated areas and address physical and social aspects of the environment that contribute to neighborhood disorder may promote mental health among Black women with SLE.

Collagen Type III and VI Remodeling Biomarkers Are Associated with Kidney Fibrosis in Lupus Nephritis

Background

Lupus nephritis (LN) occurs in <40% of patients with SLE. Reliable biomarkers of kidney damage are needed to identify patients with SLE at risk of developing LN to improve screening, treat the disease earlier, and halt progression to kidney failure. Novel biomarkers of extracellular matrix remodeling were evaluated as markers of kidney fibrosis and disease activity in patients with LN.

Methods

Biomarkers of the interstitial collagen type III (PRO-C3) and type VI (PRO-C6) formation and of collagen type III (C3M) degradation were evaluated in the serum and urine of 40 patients with LN, 20 patients with SLE but without LN, 20 healthy controls, and ten biopsy controls (histologic kidney inflammation/damage without SLE). Their association with histologic markers of interstitial fibrosis and tubular atrophy, with inflammatory cell infiltration and with disease activity and chronicity in the patients with LN was assessed.

Results

Despite PRO-C3 (serum) and PRO-C6 (serum and urine) being significantly elevated in patients with LN compared with healthy controls, the markers did not differentiate patients with LN from those with SLE. C3M (urine) levels were not different in LN compared with the other groups. C3M (urine) strongly correlated and PRO-C6 (serum and urine) inversely correlated with kidney function (eGFR). The biomarkers of interstitial collagen turnover PRO-C6 (serum) and C3M (urine) correlated with histologic markers of interstitial fibrosis, tubular atrophy, and monocyte infiltration.

Conclusions

Noninvasive collagen turnover biomarkers are promising tools to identify patients with SLE with kidney histologic modifications.

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.

Overcoming barriers to recruitment and retention of African-American women with SLE in behavioural interventions: lessons learnt from the WELL study

Background

African–Americans are historically under-represented in SLE studies and engaging them in behavioural interventions is challenging. The Women Empowered to Live with Lupus (WELL) study is a trial conducted to examine the effectiveness of the Chronic Disease Self-Management Program (CDSMP) among African–American women with SLE. We describe enrolment and retention challenges and successful strategies of the WELL study.

Methods

The Georgians Organized Against Lupus (GOAL) cohort, a population-based cohort established in Atlanta, Georgia, was used to enrol a sample of 168 African–American women with SLE into the CDSMP. The CDSMP is a 6-week, group-based programme led by peers to enhance self-management skills in people with chronic conditions. Study performance standards were predefined and close monitoring of recruitment and retention progress was conducted by culturally competent staff members. Continuous contact with participants, research coordinators’ notes and regular research team meetings served to assess barriers and define strategies needed to meet the desired recruitment and retention outcomes.

Results

While no substantial barriers were identified to enrol GOAL participants into the WELL study, WELL participants faced difficulties registering for and/or completing (attending ≥4 sessions) a CDSMP workshop. Major barriers were unpredicted personal and health-related issues, misunderstanding of the scope and benefits of the intervention, and transportation problems. Early implementation of tailored strategies (eg, CDSMP scheduled on Saturdays, CDSMP delivered at convenient/familiar facilities, transportation services) helped to reduce participant barriers and achieve a CDSMP registration of 168 participants, with 126 (75%) completers. Frequent contact with participants and compensation helped to reach 92.3% retention for the 6-month survey.

Conclusions

Predefined standards and monitoring of participant barriers by a culturally competent research team and proactive solutions were critical to implementing successful strategies and achieving the desired recruitment and retention outcomes of a behavioural trial involving African–American women with SLE.

Trial registration number

NCT02988661.

Cell-bound complement activation products associate with lupus severity in SLE

Objectives

To evaluate the association between lupus severity and cell-bound complement activation products (CB-CAPs) or low complement proteins C3 and C4.

Methods

All subjects (n=495) fulfilled the American College of Rheumatology (ACR) classification criteria for SLE. Abnormal CB-CAPs (erythrocyte-bound C4d or B-lymphocyte-bound C4d levels >99th percentile of healthy) and complement proteins C3 and C4 were determined using flow cytometry and turbidimetry, respectively. Lupus severity was estimated using the Lupus Severity Index (LSI). Statistical analysis consisted of multivariable linear regression and groups comparisons.

Results

Abnormal CB-CAPs were more prevalent than low complement values irrespective of LSI levels (62% vs 38%, respectively, p<0.0001). LSI was low (median 5.44, IQR: 4.77–6.93) in patients with no complement abnormality, intermediate in patients with abnormal CB-CAPs (median 6.09, IQR: 5.31–8.20) and high in the group presenting with both abnormal CB-CAPs and low C3 and/or C4 (median 7.85, IQR: 5.51–8.37). Odds of immunosuppressant use was higher in subjects with LSI ≥5.95 compared with subjects with LSI <5.95 (1.60 vs 0.53, p<0.0001 for both). Multivariable regression analysis revealed that higher LSI scores associated with abnormal CB-CAPs—but not low C3/C4—after adjusting for younger age, race and longer disease duration (p=0.0001), which were also independent predictors of disease severity (global R²=0.145).

Conclusion

Abnormalities in complement activation as measured by CB-CAPs are associated with increased LSI.

Feasibility and preliminary data for a State-wide South Carolina Lupus Registry

BACKGROUND

Systemic lupus erythematosus (SLE) or lupus is an autoimmune disorder whose cause and reason for disproportionate impact on minorities remains enigmatic. Furthermore, statistics describing lupus incidence and prevalence are outdated and often based on small samples. To begin to address this disparity this report describes preliminary data to be utilized in the development of a state-wide lupus registry in South Carolina.

METHODS

A prospective survey and retrospective data from the South Carolina Budget and Control Board Office of Research & Statistics were used to capture data pertaining to knowledge of lupus, prevalence, and access to lupus care.

RESULTS

Retrospective ORS data indicated there were 11,690 individuals living with lupus in 2014 with the average direct cost of $69,999.40 in medical care. Prospective surveys (N = 325), in over 16 locations in South Carolina, showed 31% knew someone with lupus, 16% had been diagnosed with lupus, and 50% did not know of a medical facility that treated lupus.

CONCLUSION

A lupus registry and repository will provide ongoing access for researchers on the impact of lupus on communities in South Carolina. Lupus is highly prevalent, but disproportionately represented in terms of patient information and participation in clinical trials, so it is also expected that this preliminary work will provide an ongoing process in which the medical community can better engage lupus patients.

Deposition of Immune Complexes in Gingival Tissues in the Presence of Periodontitis and Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a complex chronic autoimmune disease characterized by tissue damage and widespread inflammation in response to environmental challenges. Deposition of immune complexes in kidneys glomeruli are associated with lupus nephritis, determining SLE diagnosis. Periodontitis is a chronic inflammatory disease characterized by clinical attachment and bone loss, caused by a microbial challenge – host response interaction. Deposition of immune complex at gingival tissues is a common finding in the course of the disease. Considering that, the primary aim of this study is to investigate the deposition of immune complexes at gingival tissues of SLE patients compared to systemically healthy ones, correlating it to periodontal and systemic parameters. Twenty-five women diagnosed with SLE (SLE+) and 25 age-matched systemically healthy (SLE–) women were included in the study. Detailed information on overall patient's health were obtained from file records. Participants were screened for probing depth (PD), clinical attachment loss (CAL), gingival recession (REC), full-mouth bleeding score (FMBS) and plaque scores (FMPS). Bone loss was determined at panoramic X-ray images as the distance from cementenamel junction to alveolar crest (CEJ-AC). Gingival biopsies were obtained from the first 15 patients submitted to surgical periodontal therapy of each group, and were analyzed by optical microscopy and direct immunofluorescence to investigate the deposition of antigen-antibody complexes. Eleven (44%) patients were diagnosed with active SLE (SLE-A) and 14 (56%) with inactive SLE (LES-I). Mean PD, CAL and FMBS were significantly lower in SLE+ than SLE–(p < 0.05; Mann Whitney). The chronic use of low doses of immunosuppressants was associated with lower prevalence of CAL >3 mm. Immunofluorescence staining of markers of lupus nephritis and/or proteinuria was significantly increased in SLE+ compared to SLE–, even in the presence of periodontitis. These findings suggest that immunomodulatory drugs in SLE improves periodontal parameters. The greater deposition of antigen-antibody complexes in the gingival tissues of patients diagnosed with SLE may be a marker of disease activity, possibly complementing their diagnosis.

The role of Dickkopf-1 as a biomarker in systemic lupus erythematosus and active lupus nephritis

Background

Systemic lupus erythematosus (SLE) is a chronic disease which is mainly attributed to autoantibodies, cytokines, and immune complex deposition. Studies have demonstrated that cytokines and autoantibodies were strongly associated with renal diseases and can be used for the prediction of patients with lupus nephritis (LN). However, antibodies to dsDNA and the reduction of complements were also detected in non-LN patients as well as clinically non-active SLE patients. The current study was performed to detect the role of serum DKK-1 as a biomarker for the identification of SLE patients and patients with LN and its relation to disease activity and severity. The study was conducted on fifty clinically diagnosed SLE patients who were diagnosed according to Systemic Lupus International Collaborating Clinics (SLICC) classification criteria for SLE, in addition to thirty healthy control volunteers matched for age and sex. Assessment of SLE disease activity was done using Systemic Lupus Erythematosus Disease Activity Index (SLEDAI). Assessment of SLE disease severity was done using the Systemic Lupus International Collaborative Clinics/American College of Rheumatology (SLICC/ACR) damage index. Serum levels of DKK-1 were measured for all participants by ELISA using commercially available kits.

Results

DKK-1 serum levels were significantly higher among active lupus nephritis cases as compared with SLE cases with no LN and with healthy controls (9197.60 μg/uL ± 2939.2 μg/uL vs. 6405.15 μg/uL ± 2018.91 μg/uL vs. 2790.33 μg/uL ± 833.49 μg/uL) respectively (p-values < 0.001). DKK-1 concentration was significantly higher among SLE patients with positive as compared with negative anti-double-stranded DNA (dsDNA) antibodies (p-value < 0.001). According to receiver operating characteristic (ROC) curve analysis, serum DKK-1 level diagnosed the SLE at a statistically significant level with a 98% sensitivity and 70% specificity and serum DKK-1 level also diagnosed active lupus nephritis at a 90% sensitivity and 63% specificity.

Conclusion

DKK-1 could diagnose SLE and lupus nephritis with high sensitivity and specificity. Serum DKK-1 is a reliable biomarker for the identification of SLE and patients with LN and could be used as a key molecule for the diagnosis of SLE and as a prognostic indicator of LN.

One Quarter of Medicare Hospitalizations in Patients with Systemic Lupus Erythematosus Readmitted within Thirty Days

OBJECTIVE

Thirty-day hospital readmissions in systemic lupus erythematosus (SLE) approach proportions in Medicare-reported conditions including heart failure (HF). We compared adjusted 30-day readmission and mortality among SLE, HF, and general Medicare to assess predictors informing readmission prevention.

METHODS

This database study used a 20% sample of all US Medicare 2014 adult hospitalizations to compare risk of 30-day readmission and mortality among admissions with SLE, HF, and neither per discharge diagnoses (if both SLE and HF, classified as SLE). Inclusion required live discharge and ≥12 months of Medicare A/B before admission to assess baseline covariates including patient, geographic, and hospital factors. Analysis used observed and predicted probabilities, and multivariable GEE models clustered by patient to report adjusted risk ratios (ARRs) of 30-day readmission and mortality.

RESULTS

SLE admissions (n=10,868) were younger, predominantly female, more likely to be Black, disabled, and have Medicaid or end-stage renal disease (ESRD). Observed 30-day readmissions of 24% were identical for SLE and HF (p = 0.6), and higher than other Medicare (16%, p < 0.001). Both SLE and HF had elevated readmission risk (ARR 1.08, (95% CI (1.04, 1.13)); 1.11, (1.09, 1.13)). SLE readmissions were higher for Black (30%) versus White (21%) populations, and highest in ages 18-33 (39%) and ESRD (37%). Admissions of Black patients with SLE from least disadvantaged neighborhoods had highest 30-day mortality (9% versus 3% White).

CONCLUSION

Thirty-day SLE readmissions rivaled HF at 24%. Readmission prevention programs should engage young, ESRD patients with SLE and examine potential causal gaps in SLE care and transitions.

Within-trial economic analysis of flare data from the BLISS-SC trial of subcutaneous belimumab in systemic lupus erythematosus

Objective

The management of systemic lupus erythematosus (SLE) flares can incur substantial healthcare costs. In the phase III BLISS-SC trial, subcutaneous (SC) belimumab 200 mg plus standard therapy was associated with significant reductions in time to severe flare, and risk of flares, versus placebo plus standard therapy, in adults with active SLE. We evaluated whether the reduction in SLE flares with belimumab SC plus standard therapy translated to lower healthcare costs.

Methods

A retrospective, post hoc economic analysis of BLISS-SC data was conducted. Unit costs per flare from claims data were estimated and applied to flares observed in BLISS-SC to quantify costs associated with treating severe flares (primary objective) or flares of any severity (secondary objective).

Results

Of 836 patients (n=556 belimumab, n=280 placebo) analysed (94.4% female, mean (standard deviation, SD) age 38.6 (12.3) years), 13.2% and 62.8% had experienced a severe or mild/moderate flare, respectively. Mean (SD) unit costs per severe, moderate, mild or mild/moderate flare were US$9273 (38 800), US$3048 (9321), US$1671 (6202) and US$2303 (7821), respectively. Adjusted mean costs of treating flares were significantly lower with belimumab SC plus standard therapy than placebo plus standard therapy (severe flare, US$927 lower, p<0.001; flare of any severity, US$1379 lower, p<0.001).

Conclusions

This economic analysis of data from the BLISS-SC trial revealed significant cost reductions were associated with treating SLE flares with belimumab SC plus standard therapy versus placebo plus standard therapy. These findings may help to inform decision making about introducing belimumab to healthcare systems.

Trial registration number

NCT01484496.

Health disparities: Intracellular consequences of social determinants of health

Health disparities exist dependent on socioeconomic status, living conditions, race/ethnicity, diet, and exposures to environmental pollutants. Herein, the various exposures contributing to a person's exposome are collectively considered social determinants of health (SDOH), and the SDOH-exposome impacts health more than health care. This review discusses the extent of evidence of the physiologic consequences of these exposures at the intracellular level. We consider how the SDOH-exposome, which captures how individuals live, work and age, induces cell processes that modulate a conceptual "redox rheostat." Like an electrical resistor, the SDOH-exposome, along with genetic predisposition and age, regulate reductive and oxidative (redox) stress circuits and thereby stimulate inflammation. Regardless of the source of the SDOH-exposome that induces chronic inflammation and immunosenescence, the outcome influences cardiometabolic diseases, cancers, infections, sepsis, neurodegeneration and autoimmune diseases. The endogenous redox rheostat is connected with regulatory molecules such as NAD⁺/NADH and SIRT1 that drive redox pathways. In addition to these intracellular and mitochondrial processes, we discuss how the SDOH-exposome can influence the balance between metabolism and regulation of immune responsiveness involving the two main molecular drivers of inflammation, the NLRP3 inflammasome and NF-κB induction. Mitochondrial and inflammasome activities play key roles in mediating defenses against pathogens and controlling inflammation before diverse cell death pathways are induced. Specifically, pyroptosis, cell death by inflammation, is intimately associated with common disease outcomes that are influenced by the SDOH-exposome. Redox influences on immunometabolism including protein cysteines and ion fluxes are discussed regarding health outcomes. In summary, this review presents a translational research perspective, with evidence from in vitro and in vivo models as well as clinical and epidemiological studies, to outline the intracellular consequences of the SDOH-exposome that drive health disparities in patients and populations. The relevance of this conceptual and theoretical model considering the SARS-CoV-2 pandemic are highlighted. Finally, the case of asthma is presented as a chronic condition that is modified by adverse SDOH exposures and is manifested through the dysregulation of immune cell redox regulatory processes we highlight in this review.

Age differences in secular trends in black-white disparities in mortality from systemic lupus erythematosus among women in the United States from 1988 to 2017

OBJECTIVE

To examine the age differences in secular trends in black-white disparities in mortality from systemic lupus erythematosus (SLE) among women in the United States from 1988 to 2017.

METHODS

We used mortality data to calculate age-specific SLE and all-causes (as reference) mortality rates and black/white mortality rates ratios among women from 1988 to 2017. Annual percent change was estimated using joinpoint regression analysis.

RESULTS

We identified 10,793 and 4,165,613 black women and 19,455 and 31,129,528 white women who died between 1988 and 2017 from SLE and all-causes, respectively. The black/white SLE mortality rate ratio according joinpoint regression model was 6.6, 7.2, 4.4, and 1.4 for decedents aged 0-24, 25-44, 45-64, and 65+ years in 1988 and was 7.2, 5.9, 4.1, and 1.9, respectively in 2017. No significant decline trend was noted and the annual percent change was 0.3%, -0.7%, -0.2%, and 1.0%, respectively. On the contrast, the black/white all-causes mortality rate ratio was 2.0, 2.5, 1.8, and 1.0, respectively in 1988 and was 1.7, 1.3, 1.5, and 0.9, respectively in 2017, a significant decline trend was noted in each age group.

CONCLUSIONS

Black adults, youths and adolescents had four to seven times higher SLE mortality rates than their white counterparts and the black-white disparities persisted during the past three decades. On the contrast, black women had less than two times higher all-causes mortality rates than their white counterparts and black-white disparities significantly diminish during the past three decades.

Community-Engaged Research: Leveraging Community-Academic Partnerships to Reduce Disparities and Inequities in Lupus Care

Community-engaged research is an effective tool to address health care disparities and inequities in lupus care. Community-based participatory research allows the highest degree of community engagement, but may be limited by the challenges associated with long-term funding and implementation. Community-academic partnerships are a feasible way to allow for varying degrees of community engagement and develop sustainable infrastructure. Two examples of community-engaged research in rheumatology are MONARCAS and Lupus Conversations.

High Disease Severity Among Asians in a US Multiethnic Cohort of Individuals with Systemic Lupus Erythematosus

OBJECTIVE

Knowledge about systemic lupus erythematosus (SLE) outcomes among US Asians is lacking. We examined SLE disease activity, severity, and damage among Asians of primarily Chinese and Filipino descent in a multiethnic cohort.

METHODS

California Lupus Epidemiology Study (CLUES, n=328) data were analyzed. Data were collected in English, Cantonese, Mandarin or Spanish, using validated instruments for disease activity (Systemic Lupus Erythematosus Disease Activity Index), disease severity (Lupus Severity Index [LSI]) and disease damage (Systemic Lupus International Collaborating Clinics Damage Index). We assessed differences in SLE outcomes among racial/ethnic groups using multivariable linear regression including interaction terms for age at diagnosis and race/ethnicity.

RESULTS

Asians were the largest racial/ethnic group (38%; [Chinese=22%; Filipino=9%; Other=7%]). Average age at diagnosis (years) was younger among Asians (27.9), particularly Filipinos (22.2), compared with Whites (29.4) and Blacks (34.0). After adjustment, disease activity and damage were not significantly different across groups. Disease severity among Asians was significantly higher than Whites (LSI 7.1 vs 6.5; p<0.05) but similar to Blacks and Hispanics. Early age at diagnosis was associated with greater organ damage among Asians, Blacks, and Hispanics, but not Whites.

CONCLUSIONS

SLE was more severe among US Asians compared to Whites. Filipinos were affected at strikingly young ages. Asians and non-White groups with younger age at diagnosis had greater organ damage than Whites. Such racial/ethnic distinctions suggest the need for heightened clinical awareness to improve health outcomes among Asians with SLE. Further study of SLE outcomes across a range of US Asian subgroups is important.

Developing and Validating Methods to Assemble Systemic Lupus Erythematosus Births in the Electronic Health Record

OBJECTIVE

Electronic health records (EHRs) represent powerful tools to study rare diseases. We developed and validated EHR algorithms to identify SLE births across centers.

METHODS

We developed algorithms in a training set using an EHR with over 3 million subjects and validated algorithms at two other centers. Subjects at all 3 centers were selected using ≥ 1 SLE ICD-9 or SLE ICD-10-CM codes and ≥ 1 ICD-9 or ICD-10-CM delivery code. A subject was a case if diagnosed with SLE by a rheumatologist and had a birth documented. We tested algorithms using SLE ICD-9 or ICD-10-CM codes, antimalarial use, a positive antinuclear antibody ≥ 1:160, and ever checked dsDNA or complements using both rule-based and machine learning methods. Positive predictive values (PPVs) and sensitivities were calculated. We assessed the impact of case definition, coding provider, and subject race on algorithm performance.

RESULTS

Algorithms performed similarly across all three centers. Increasing the number of SLE codes, adding clinical data, and having a rheumatologist use the SLE code all increased the likelihood of identifying true SLE patients. All the algorithms had higher PPVs in African American vs. Caucasian SLE births. Using machine learning methods, total number of SLE codes and a SLE code from a rheumatologist were the most important variables in the model for SLE case status.

CONCLUSION

We developed and validated algorithms that use multiple types of data to identify SLE births in the EHR. Algorithms performed better in African American mothers than Caucasian mothers.

Development and validation of lupus nephritis case definitions using United States veterans affairs electronic health records

OBJECTIVE

International Classification of Diseases (ICD) codes are commonly used to identify patients with rare diseases in electronic health records (EHRs). However, misclassification is common, impacting the validity of study results. In this study, we compared the accuracies of several ICD-based case definitions of lupus nephritis (LN) in identifying United States veterans with LN.

METHODS

Using the Department of Veterans Affairs (VA) EHR, we identified all veterans with ≥1 ICD-9 or 10 diagnostic codes for systemic lupus erythematosus (SLE) between October 1, 1999 and September 30, 2017. A cohort was randomly selected for diagnostic validation and 9 ICD-based LN case definitions were applied to this cohort. The diagnostic accuracy of each definition was assessed against gold standard criterion of biopsy-proven LN.

RESULTS

18,420 veterans had ≥1 ICD-9 or 10 diagnostic codes for SLE; 981 were randomly selected for diagnostic validation. 95 veterans (9.7%) had biopsy-proven LN. The case definitions had high specificity and NPV but variable sensitivity and PPV. The definition containing ≥2 ICD -9 codes for SLE and ≥2 nephritis indicators had the highest combination of sensitivity and specificity (87.4% and 94.6% respectively). ICD-10 code for LN had high specificity (99.8%) and PPV (93.9%).

CONCLUSION

ICD-based case definitions of LN in the VA population have high specificity and NPV but variable sensitivity and PPV. Our results may help guide the design of future LN studies in VA cohorts. The choice of specific case definitions depends on the relative importance of different accuracy measures to individual studies.

Venous Thromboembolic Events in African American Lupus Patients are Less Likely Associated with Antiphospholipid Antibodies Compared to Caucasians

OBJECTIVE

The risk of thrombotic events is elevated in patients with systemic lupus erythematosus (SLE) compared to the general population, and has been attributed to both systemic inflammation, as well as presence of antiphospholipid antibodies (aPL). We examined differences in aPL prevalence in Caucasian and African American (AA) patients with SLE and venous thromboembolic (VTE) events, and compared inflammatory markers at time of VTE event.

METHODS

Records of Caucasian and AA patients with SLE and VTE events were retrieved from a Rheumatology practice based at an academic hospital. A clinically significant aPL profile was defined as anti-cardiolipin IgG/IgM and/or anti-β₂ glycoprotein-I IgG/IgM ≥40 units, and/or positive lupus anticoagulant (LA) ≥1.3. Logistic regression was used to determine predictors of a clinically significant aPL profile.

RESULTS

Ninety-seven patients fulfilled ACR and/or 2012 SLICC classification criteria for SLE, had history of VTE and available aPL tests (59 Caucasian and 38 AA). African Americans were 66% less likely (95% CI 0.12, 0.96; p=0.04) to have a clinically significant aPL profile compared to Caucasians in multivariable regression. Triple positivity was most frequent among Caucasians, while 7/8 AAs had a positive LA test. At time of VTE event, AAs had significantly higher levels of anti-dsDNA (p=0.02), lower hemoglobin (p=0.01), and higher erythrocyte sedimentation rate (p=0.008).

CONCLUSION

Among patients with SLE and VTE events, AAs were less likely to have a clinically significant aPL profile compared to Caucasians indicating that a negative aPL profile in AA does not decrease VTE risk.

Anti-Müllerian hormone in African-American women with systemic lupus erythematosus

OBJECTIVE

Women with SLE may experience ovarian insufficiency or dysfunction due to treatment or disease effects. Anti-Müllerian hormone (AMH), a marker of ovarian reserve, has been examined in small populations of women with SLE with conflicting results. To date, these studies have included very few African-American women, the racial/ethnic group at greatest risk of SLE.

METHODS

We enrolled African-American women aged 22-40 years diagnosed with SLE after age 17 from the Atlanta Metropolitan area. Women without SLE from the same area were recruited from a marketing list for comparison. AMH was measured in serum using the Ansh Labs assay (Webster, Texas, USA). We considered AMH levels <1.0 ng/mL and AMH <25th percentile of comparison women as separate dichotomous outcomes. Log-binomial regression models estimating prevalence ratios were adjusted for age, body mass index and hormonal contraception use in the previous year.

RESULTS

Our sample included 83 comparison women without SLE, 68 women with SLE and no history of cyclophosphamide (SLE/CYC-) and 11 women with SLE and a history of cyclophosphamide treatment (SLE/CYC+). SLE/CYC+ women had a greater prevalence of AMH <1.0 ng/mL compared with women without SLE (prevalence ratio (PR): 2.90, 95% CI: 1.29 to 6.51). SLE/CYC- women were also slightly more likely to have AMH <1.0 ng/mL (PR: 1.62, 95% CI: 0.93 to 2.82) than comparison women. Results were similar when considering AMH <25th percentile by age of comparison women.

CONCLUSIONS

Treatment with CYC is associated with low AMH in African-American women with SLE. SLE itself may also be associated with reduced AMH, but to a lesser extent.

Disparities in Lupus and Lupus Nephritis Care and Outcomes Among US Medicaid Beneficiaries

Systemic lupus erythematosus (SLE) is a serious chronic autoimmune disease with substantial morbidity and mortality. Although improved diagnostics and therapeutics have contributed to declining mortality rates, important disparities exist in SLE survival rates by race, ethnicity, gender, age, country, and social disadvantage. This review highlights the burden of SLE and lupus nephritis among Medicaid beneficiaries, outlines barriers in access to high-quality SLE care and medication adherence in the Medicaid SLE population, and summarizes disparities in adverse outcomes among SLE patients enrolled in Medicaid.

Evaluation of the Economic Benefit of Earlier Systemic Lupus Erythematosus (SLE) Diagnosis Using a Multivariate Assay Panel (MAP)

Objective

Diagnosis of systemic lupus erythematosus (SLE) made by standard diagnostic laboratory tests (SDLTs) has sensitivity and specificity of 83% and 76%, respectively. A multivariate assay panel (MAP) combining complement C4d activation products on erythrocytes and B cells with SDLTs yields a sensitivity and specificity of 80% and 86%, respectively, presumably enabling earlier SLE diagnosis at lower severity, with associated lower health care costs compared with SDLT diagnoses. We compared the payer budget impact of diagnosing SLE using MAP (incremental cost of $108) versus SDLTs.

Methods

We modeled a health plan of 1 million enrollees. SLE diagnosis among suspected patients was 9.2%. The MAP arm assumed 80%/20% of patients were tested with MAP/SDLTs, versus 100% tested with SDLTs in the SDLT arm. Prediagnosis direct costs were estimated from claims data, and postdiagnosis costs were obtained from the literature. Based on improved MAP performance, the assumed hazard ratio for diagnosis rate compared with SDLTs was 1.74 (71%, 87%, 90%, and 91% of patients who develop SLE are diagnosed in years 1 to 4 compared with 53%, 75%, 84%, and 88% of patients diagnosed with SDLTs).

Results

Total 4‐year pre‐ and postdiagnosis direct costs for patients with suspected SLE tested with MAP were $59 183 666 compared with $61 174 818 tested by SDLTs, with lower costs in the MAP arm due primarily to prediagnosis savings related to reduced hospital admissions.

Conclusion

Incorporating MAP into SLE diagnosis results in estimated 4‐year direct cost savings of $1 991 152 ($0.04 per member per month). By facilitating earlier diagnosis of SLE, MAP may enhance patient outcomes.

Understanding the Disproportionate Burden of Rheumatic Diseases in Indigenous North American Populations

Studies have described a high incidence and prevalence of several rheumatic diseases in indigenous North American populations. Conditions studied most frequently with consistently high burden of disease include rheumatoid arthritis, spondyloarthritis, and systemic lupus erythematosus. Crystal-induced arthritis has been reported to have a lower prevalence than expected. Information about genetic and environmental risk factors is available for some of these conditions. An awareness of the epidemiology of rheumatic diseases in indigenous North American populations is important for clinicians involved in caring for patients in these populations as well as for planning health service delivery in these communities.

Examining Racial Differences in Access to Primary Care for People Living with Lupus: Use of Ambulatory Care Sensitive Conditions to Measure Access

Background

People living with lupus may experience poor access to primary care and delayed specialty care.

Purpose

To identify characteristics that lead to increased odds of poor access to primary care for minorities hospitalized with lupus.

Methods

Cross-sectional design with 2011-2012 hospitalization data from South Carolina, North Carolina, and Florida. We used ICD-9 codes to identify lupus hospitalizations. Ambulatory care sensitive conditions were used to identify preventable lupus hospitalizations and measure access to primary care. Logistic regression was used to estimate the odds ratio for the association between predictors and having poor access to primary care. Sensitivity analysis excluded patients aged >65 years.

Results

There were 23,154 total lupus hospitalizations, and 2,094 (9.04%) were preventable. An adjusted model showed minorities aged ≥65 years (OR 2.501, CI 1.501, 4.169), minorities aged 40-64 years (OR 2.248, CI: 1.394, 3.627), minorities with Medicare insurance (OR 1.669, CI:1.353,2.059) and minorities with Medicaid (OR 1.662,CI:1.321, 2.092) had the highest odds for a preventable lupus hospitalization. Minorities with Medicare had significantly higher odds for ≥3 hospital days (OR 1.275, CI: 1.149, 1.415). Whites with Medicare (OR 1.291, CI: 1.164, 1.432) had the highest odds for ≥3 days.

Conclusions

Our data show that middle-aged minorities living with lupus and on public health insurance have a higher likelihood of poor access to primary care. Health care workers and policymakers should develop plans to identify patients, explore issues affecting access, and place patients with a community health worker or social worker to promote better access to primary care.

Infertility Among African American Women With Systemic Lupus Erythematosus Compared to Healthy Women: A Pilot Study

OBJECTIVE

Some treatments for systemic lupus erythematosus (SLE) can cause infertility, but the effect of SLE itself on fertility, particularly in African American women, is less clear. We undertook this study to examine infertility experiences in African American women with SLE compared to healthy women.

METHODS

We enrolled women ages 22-40 years living in the Atlanta metropolitan area who were diagnosed with SLE after age 17 years. Women who had ever been treated with cyclophosphamide or who had a hysterectomy were excluded. African American women ages 22-40 years who were from the same area and recruited from a marketing list were used for comparison. Women were interviewed about their reproductive histories and goals. Periods of infertility were identified as times when women had regular, unprotected sex for ≥12 months without conceiving after 20 years of age. We separately considered any period of infertility and periods of infertility when attempting pregnancy. We used Cox proportional hazards regression to examine the association between SLE and time to infertility. Models were adjusted for age, nulliparity, and smoking. An age-matched analysis was also conducted to examine periods of infertility occurring after SLE diagnosis.

RESULTS

Our sample included 75 women with SLE and 154 women without SLE. SLE was associated with any infertility (adjusted hazard ratio [HRadj ] 2.08 [95% confidence interval (95% CI) 1.38-3.15]), but less so with infertility when attempting pregnancy (HRadj 1.30 [95% CI 0.62-2.71]). The matched analysis generated similar point estimates.

CONCLUSION

Women with SLE may be more likely to experience episodes of infertility, but this may not translate to an inability to meet reproductive goals.

Impact of IL-10 gene polymorphisms and its interaction with environment on susceptibility to systemic lupus erythematosus

This study aims to explore the impact of interleukin (IL)-10 single nucleotide polymorphisms (SNPs) and its interaction with environment on the risk of systemic lupus erythematosus (SLE). Chi-square testing method was used to investigate whether the distributions for genotype of four SNPs were differed from Hardy-Weinberg equilibrium (HWE). Logistic regression was used to test the association between IL-10 SNPs and SLE risk. The best interaction combinations between IL-10 SNPs and environmental factors were assessed by generalized multifactor dimensionality reduction (GMDR). Both rs1800896-G and rs1800871-T alleles were associated with increased risk of SLE, the odds ratios (ORs) (95% confidence interval (CI)) for the two SNPs were 1.68 (1.25-2.09) and 1.47 (1.12-1.94), respectively. Then, we used the GMDR method to analyze the high-order interactions of four SNPs within IL-10 gene and environmental factors on SLE risk. We found a significant interaction combination (two-locus model with P = 0.001) between rs1800896 and smoking, after adjusting for gender, age, body mass index (BMI), and alcohol drinking. We also used two-variable stratified analysis by logistic regression to analyze the synergistic effect between two variables (rs1800896 and smoking), which had significant significance in GMDR model. We found that current smokers with rs1800896-AG or GG genotype have the highest SLE risk, compared with never smokers with the rs1800896-AA genotype, OR (95% CI) = 2.24 (1.52-3.58). The rs1800896-G and rs1800871-T alleles and interaction between rs1800896 and current smoking were all associated with increased risk of SLE.

Insights From Twitter Conversations on Lupus and Reproductive Health: Protocol for a Content Analysis

Background

Systemic lupus erythematosus (SLE) is the most common form of lupus. It is a chronic autoimmune disease that predominantly affects women of reproductive age, impacting contraception, fertility, and pregnancy. Although clinic-based studies have contributed to an increased understanding of reproductive health care needs of patients with SLE, misinformation abounds and perspectives on reproductive health issues among patients with lupus remain poorly understood. Social networks such as Twitter may serve as a data source for exploring how lupus patients communicate about their health issues, thus adding a dimension to enrich our understanding of communication regarding reproductive health in this unique patient population.

Objective

The objective of this study is to conduct a content analysis of Twitter data published by users in English in the United States from September 1, 2017, to October 31, 2018, in order to examine people’s perspectives on reproductive health among patients with lupus.

Methods

This study will analyze user-generated posts that include keywords related to lupus and reproductive health from Twitter. To access public Twitter user data, we will use Symplur Signals, a health care social media analytics platform. Text classifiers will be used to identify topics in posts. Posts will be classified manually into the a priori and emergent categories. Based on the information available in a user’s Twitter profile (ie, username, description, and profile image), we will further attempt to characterize the user who generated the post. We will use descriptive statistics to analyze the data and identify the most prevalent topics in the Twitter content among patients with lupus.

Results

This study has been funded by the National Center for Advancing Translational Science (NCATS) through their Clinical and Translational Science Awards program. The Institutional Review Board at the University of Southern California approved the study (HS-18-00912). Data extraction and cleaning are complete. We obtained 47,715 Twitter posts containing terms related to “lupus” from users in the United States, published in English between September 1, 2017, and October 31, 2018. We will include 40,885 posts in the analysis, which will be completed in fall 2020. This study was supported by funds from the has been funded by the National Center for Advancing Translational Science (NCATS) through their Clinical and Translational Science Awards program.

Conclusions

The findings from this study will provide pilot data on the use of Twitter among patients with lupus. Our findings will shed light on whether Twitter is a promising data source for learning about reproductive health issues expressed among patients with lupus. The data will also help to determine whether Twitter can serve as a potential outreach platform for raising awareness of lupus and reproductive health and for implementing relevant health interventions.

International Registered Report Identifier (IRRID)

DERR1-10.2196/15623

Discontinuation of hydroxychloroquine in older patients with systemic lupus erythematosus: a multicenter retrospective study

Background

Although hydroxychloroquine (HCQ) is a mainstay of treatment for patients with systemic lupus erythematosus (SLE), ocular toxicity can result from accumulated exposure. As the longevity of patients with SLE improves, data are needed to balance the risk of ocular toxicity and the risk of disease flare, especially in older patients with quiescent disease. Accordingly, this study was initiated to examine the safety of HCQ withdrawal in older SLE patients.

Methods

Data were obtained by retrospective chart review at three major lupus centers in New York City. Twenty-six patients who discontinued HCQ and thirty-two patients on HCQ matched for gender, race/ethnicity, and age were included in this study. The primary outcome was the occurrence of a lupus flare classified by the revised version of the Safety of Estrogens in Lupus Erythematosus: National Assessment version of the Systemic Lupus Erythematosus Disease Activity Index (SELENA-SLEDAI) Flare composite index, within 1 year of HCQ withdrawal or matched time of continuation.

Results

Five patients (19.2%) in the HCQ withdrawal group compared to five (15.6%) in the HCQ continuation group experienced a flare of any severity (odds ratio [OR] = 1.28; 95% CI 0.31, 5.30; p = 0.73). There were no severe flares in either group. The results were similar after adjusting for length of SLE, number of American College of Rheumatology criteria, low complement levels, and SELENA-SLEDAI score, and in a propensity score analysis (OR = 1.18; 95% CI 0.23, 6.16; p = 0.84). The analysis of time to any flare revealed a non-significant earlier time to flare in the HCQ withdrawal group (log-rank p = 0.67). Most flares were in the cutaneous and musculoskeletal systems, but one patient in the continuation group developed pericarditis. The most common reason for HCQ withdrawal was retinal toxicity (42.3%), followed by patient’s preference (34.6%), other confirmed or suspected adverse effects (15.4%), ophthalmologist recommendation for macular degeneration (3.8%), and rheumatologist recommendation for quiescent SLE (3.8%).

Conclusions

In this retrospective study of older stable patients with SLE on long-term HCQ, withdrawal did not significantly increase the risk of flares.

Patient ancestry significantly contributes to molecular heterogeneity of systemic lupus erythematosus

Gene expression signatures can stratify patients with heterogeneous diseases, such as systemic lupus erythematosus (SLE), yet understanding the contributions of ancestral background to this heterogeneity is not well understood. We hypothesized that ancestry would significantly influence gene expression signatures and measured 34 gene modules in 1566 SLE patients of African ancestry (AA), European ancestry (EA), or Native American ancestry (NAA). Healthy subject ancestry-specific gene expression provided the transcriptomic background upon which the SLE patient signatures were built. Although standard therapy affected every gene signature and significantly increased myeloid cell signatures, logistic regression analysis determined that ancestral background significantly changed 23 of 34 gene signatures. Additionally, the strongest association to gene expression changes was found with autoantibodies, and this also had etiology in ancestry: the AA predisposition to have both RNP and dsDNA autoantibodies compared with EA predisposition to have only anti-dsDNA. A machine learning approach was used to determine a gene signature characteristic to distinguish AA SLE and was most influenced by genes characteristic of the perturbed B cell axis in AA SLE patients.

Transcriptional profiling of lupus patients and healthy controls reveals ancestry-related differences and transcriptional heterogeneity among lupus patients.

Racial and Ethnic Differences in the Prevalence and Time to Onset of Manifestations of Systemic Lupus Erythematosus: The California Lupus Surveillance Project

OBJECTIVE

The California Lupus Surveillance Project (CLSP) is a population-based registry of individuals with systemic lupus erythematosus (SLE) residing in San Francisco County, California from 2007 to 2009, with a special focus on Asian/Pacific Islander and Hispanic patients. We used retrospective CLSP data to analyze racial and ethnic differences in lupus manifestations and in the timing and risk of developing severe manifestations.

METHODS

A total of 724 patients with SLE were retrospectively identified. Prevalence ratios (PRs) of SLE manifestations were calculated using Poisson regression models stratified by race/ethnicity and adjusted for sex, age at SLE diagnosis, and disease duration. We studied onset of severe SLE manifestations after SLE diagnosis using Kaplan-Meier methods to examine time-to-event and Cox proportional hazards regression models to estimate hazard ratios (HRs). White patients were the referent group in all analyses.

RESULTS

African Americans, Asian/Pacific Islanders, and Hispanic patients had increased prevalence of renal manifestations (PR 1.74 [95% confidence interval (95% CI) 1.40-2.16], PR 1.68 [95% CI 1.38-2.05], and PR 1.35 [95% CI 1.05-1.74], respectively). Furthermore, African Americans had increased prevalence of neurologic manifestations (PR 1.49 [95% CI 1.12-1.98]), and both African Americans (PR 1.09 [95% CI 1.04-1.15]) and Asian/Pacific Islanders (PR 1.07 [95% CI 1.01-1.13]) had increased prevalence of hematologic manifestations. African Americans, Asian/Pacific Islanders, and Hispanic patients, respectively, had higher risk of developing lupus nephritis (HR 2.4 [95% CI 1.6-3.8], HR 4.3 [95% CI 2.9-6.4], and HR 2.3 [95% CI 1.4-3.8]) and thrombocytopenia (HR 2.3 [95% CI 1.1-4.4], HR 2.3 [95% CI 1.3-4.2], and HR 2.2 [95% CI 1.1-4.7]). Asian/Pacific Islander and Hispanic patients had higher risk of developing antiphospholipid syndrome (HR 2.5 [95% CI 1.4-4.4] and HR 2.6 [95% CI 1.3-5.1], respectively).

CONCLUSION

This is the first epidemiologic study comparing lupus manifestations among 4 major racial and ethnic groups. We found substantial differences in the prevalence of several clinical SLE manifestations among racial/ethnic groups and discovered that African Americans, Asian/Pacific Islanders, and Hispanic patients are at increased risk of developing several severe manifestations following a diagnosis of SLE.

Association of Poverty Income Ratio with Physical Functioning in a Cohort of Patients with Systemic Lupus Erythematosus

OBJECTIVE

To examine the association of income relative to the poverty threshold [poverty income ratio (PIR)] with self-reported physical functioning (PF) in a cohort of patients with systemic lupus erythematosus.

METHODS

We used cross-sectional data on 744 participants from Georgians Organized Against Lupus (GOAL), and secondary analyses used data on 56 participants from a nested pilot study. Primary analyses used multivariable linear regression to estimate the association between PIR (categorized as < 1.00, 1.00-1.99, 2.00-3.99, and ≥ 4.00; lower PIR indicate higher poverty) and PF (scaled subscore from the Medical Outcomes Study Short Form-12 survey; range 0-100, higher scores indicate better functioning). Secondary analyses summarized complementary measures of PF as means or percentages by PIR (categorized as < 1.00, 1.00-1.99, and ≥ 2.00).

RESULTS

The mean age of participants was 48.0 years; 6.7% were male; 80.9% were black; and 37.5%, 21.0%, 29.6%, and 12.0% had PIR of < 1.00, 1.00-1.99, 2.00-3.99, and ≥ 4.00, respectively. The overall mean PF score was 45.8 (36.2, 40.7, 55.5, and 61.2 for PIR of < 1.00, 1.00-1.99, 2.00-3.99, and ≥ 4.00). With adjustment, higher PIR remained associated with higher PF scores [2.00-3.99 vs 1.00-1.99: β = 10.9 (95% CI 3.3-18.6); ≥ 4.00 vs 1.00-1.99: β = 16.2 (95% CI 6.4-26.0)]. In secondary analyses, higher PIR was also associated with higher scores for objective physical performance.

CONCLUSION

Our results show that higher income relative to the poverty threshold is associated with better PF across multiple domains, warranting further research into multicomponent functional assessments to develop individual treatment plans and potentially improve socioeconomic disparities in outcomes.

Update on lupus epidemiology: advancing health disparities research through the study of minority populations

The current review focuses on recent population-based studies that have examined the burden of lupus, disease outcomes, and gaps in quality of care, with an emphasis in research addressing health disparities.

Integrated urine proteomics and renal single-cell genomics identify an IFN-γ response gradient in lupus nephritis

Lupus nephritis, one of the most serious manifestations of systemic lupus erythematosus (SLE), has a heterogeneous clinical and pathological presentation. For example, proliferative nephritis identifies a more aggressive disease class that requires immunosuppression. However, the current classification system relies on the static appearance of histopathological morphology, which does not capture differences in the inflammatory response. Therefore, a biomarker grounded in the disease biology is needed in order to understand the molecular heterogeneity of lupus nephritis and identify immunologic mechanism and pathways. Here, we analyzed the patterns of 1000 urine protein biomarkers in 30 patients with active lupus nephritis. We found that patients stratify over a chemokine gradient inducible by IFN-γ. Higher values identified patients with proliferative lupus nephritis. After integrating the urine proteomics with the single-cell transcriptomics of kidney biopsies, we observed that the urinary chemokines defining the gradient were predominantly produced by infiltrating CD8+ T cells, along with natural killer and myeloid cells. The urine chemokine gradient significantly correlated with the number of kidney-infiltrating CD8+ cells. These findings suggest that urine proteomics can capture the complex biology of the kidney in lupus nephritis. Patient-specific pathways could be noninvasively tracked in the urine in real time, enabling diagnosis and personalized treatment.

Incidence and Prevalence of Juvenile Systemic Lupus Erythematosus in Korea: Data From the 2017 National Health Claims Database

OBJECTIVE

The purpose of the present study was to investigate the prevalence and incidence of juvenile systemic lupus erythematosus (JSLE) in Korea.

METHODS

The data were collected from the National Health Insurance Claims Database of Korea. JSLE was identified using the diagnostic code M32 from the Korean Standard Classification of Diseases. Patients between 5 and 18 years old, who had at least 1 claim for JSLE from January 1, 2016, to December 31, 2017, as final diagnosis, were analyzed in the study. For prevalent cases, patients who used, at least 1 time, any type of medical services with a diagnostic code of M32 were selected. For incident cases, patients who did not use medical services with the M32 code 1 year prior and who were newly registered in 2017 were defined. Change-point analysis was used to find the age at which changes in prevalence and incidence occurred.

RESULTS

The prevalence of JSLE was 6.92 per 100,000 persons and the incidence of JSLE was 2.76 per 100,000 person-years in patients between 5 and 18 years old. The prevalence and incidence of JSLE were higher in females than in males. According to the change-point analysis, we found that the incidence and prevalence of female patients increased rapidly at the ages of 14 and 15 years, respectively.

CONCLUSION

This Korean population-based epidemiological study of JSLE showed similar epidemiologic profiles to Asian population in other studies. The distribution of age, ethnicity, and pubertal status are important factors that influence population estimates of JSLE incidence and prevalence.

Clinical significance of non-thyroidal illness syndrome on disease activity and dyslipidemia in patients with SLE

Objectives

Nonthyroidal illness syndrome (NTIS), also known as low triiodothyronine (T3) syndrome, frequently affects patients with systemic lupus erythematosus (SLE) and may affect lipid metabolism. Dyslipidemia is highly prevalent and associated with the long-term prognosis of SLE. The aim of the present study was to explore the clinical significance of NTIS on disease activity and dyslipidemia in patients with SLE.

Methods

Clinical and laboratory data were collected retrospectively from 223 patients with SLE. The correlation between free triiodothyronine (FT3), SLE disease activity, and lipid profiles were estimated. The correlation coefficient (r) was calculated using a Pearson’s regression model. Univariate and multivariate logistic regression analyses were performed to identify the risk factors for dyslipidemia in SLE.

Results

Serum FT3 levels were negatively correlated with the levels of 24 h urine protein (UP), blood urea nitrogen (BUN), creatinine (Cr) and SLE disease activity index (SLEDAI) (all p < 0.001) in NTIS patients but not in euthyroid patients. ApoB/ApoA1 was significantly correlated with SLEDAI (p < 0.01) in NTIS patients and CRP (p < 0.001) and ESR (p < 0.01) in euthyroid patients. A multivariate analysis revealed that only FT3 exhibited an independent negative association with dyslipidemia (P = 0.01; OR = 0.48; 95% CI 0.27–0.85).

Conclusion

NTIS frequently occurs in patients with SLE. Low FT3 is associated with disease activity in SLE patients complicated with NTIS. Low FT3 is an independent risk factor for dyslipidemia in patients with SLE.

Racism-related stress and psychological distress: Black Women's Experiences Living with Lupus study

Disparate health consequences in African American women with systemic lupus erythematosus include greater severity of physical and psychological distress. Racism-related stress is also related to psychological distress correlates in this population. This study examined the relationships between racism-related experiences, psychological distress, and systemic lupus erythematosus activity in 430 African American women from the Black Women's Experiences Living with Lupus study. The structural equation model suggests that psychological distress mediates the relationship between racism-related stress and systemic lupus erythematosus disease activity. The impact of racism-related stress on systemic lupus erythematosus disease activity may occur primarily through their impact on psychological health variables. Implications for clinical care and future directions are explored.

Lupus patient decisions about clinical trial participation: a qualitative evaluation of perceptions, facilitators and barriers

Objective

Although SLE disproportionately affects minority racial groups, they are significantly under-represented in clinical trials in the USA. This may lead to misleading conclusions in race-based subgroup analyses. We conducted focus groups to evaluate the perceptions of diverse patients with lupus about clinical trial participation.

Methods

A qualitative research design employed three 90 min focus groups led by a trained moderator and guided by the Theory of Planned Behaviour. Open-ended questions about trial participation included advantages and disadvantages (behavioural beliefs), approving and disapproving significant others (normative beliefs), and participation enhancers and barriers (control beliefs). Discussions were recorded, transcribed and analysed to identify emerging themes.

Results

Patients with SLE (n=23) aged 21-72, with increased proportion of minority groups (65%), participated. Reported advantages of trial participation included altruism and personal benefit. Disadvantages included uncertainties, disappointment, information burden, and life-health balance. Although some patients had discussed research participation with approving or disapproving family or friends, self-approval superseded external approval. Barriers included logistics and time, and facilitators included flexibility in scheduling, advance notice of studies, streamlined forms, and hope for SLE improvement.

Conclusions

Knowledge about potential benefits of clinical trial participation was high. Minority patients demonstrated confidence in making their own informed decisions, but major barriers for all participants included burdensome forms, travel, childcare, and work. These suggest a major impact on minority and all recruitment from behavioural and control aspects, which should be considered in the logistics of trial design. This does not minimise the potential importance of improved access and education about clinical research.

Characteristics and Symptom Severity of Patients Reporting Systemic Lupus Erythematosus in the PatientsLikeMe Online Health Community: A Retrospective Observational Study

INTRODUCTION

Online health communities and research networks such as PatientsLikeMe (PLM) capture patient perspectives of diseases, including systemic lupus erythematosus (SLE). We performed a retrospective observational study of data provided by patients in the PLM SLE community to characterize demographics, clinical characteristics, patient experience, and symptom impact.

METHODS

Adults who registered with PLM in 2011-2017 and reported SLE diagnosis and treatment with one or more SLE-related drug (antimalarials, immunosuppressives, corticosteroids, calcineurin inhibitors, or biologics) were included in the analysis. Information reported within 30 days from PLM registration was used to assess patient eligibility; demographics and clinical characteristics; and primary outcome measures of SLE treatments, symptoms, primary lupus manifestations, and comorbidities.

RESULTS

Among 21,101 PLM members included in this analysis, median ages at registration, onset of SLE symptoms, and SLE diagnosis were 46 years (interquartile range [IQR] 38-53, n = 21,101), 30 years (IQR 21-39; n = 6489), and 36 years (IQR 27-44; n = 6936), respectively. Most patients were female (96.8%, n = 20,370). Country of residence was reported by 19,502 patients (92.4%), of whom 18,491 (94.8%) were US residents. Race was recorded by 17,994 patients (85.3%), of whom 67.8% were white and 22.4% were black/African American. Patients reported a mean of 2.2 SLE-related medications, including antimalarials (83.8%), corticosteroids (78.8%), immunosuppressives (32.3%), and biologics (9.4%). Fatigue, pain, and joint pain were rated as moderate or severe by at least 80% of patients who reported these symptoms. Reported primary lupus manifestations and comorbidities included fibromyalgia (7.9%), discoid lupus (6.8%), lupus nephritis (6.3%), rheumatoid arthritis (4.8%), subacute cutaneous lupus (4.7%), central nervous system lupus (3.9%), Sjögren's syndrome (3.9%), and lupus pneumonitis (3.1%).

CONCLUSIONS

Age, sex, and race of patients in the PLM SLE community are broadly consistent with characteristics of the general SLE population in the United States. The PLM SLE population may provide valuable data on self-reported patient experience. Plain language summary available for this article.

Area-Level Predictors of Medication Nonadherence Among US Medicaid Beneficiaries With Lupus: A Multilevel Study

OBJECTIVE

Adherence to hydroxychloroquine (HCQ) treatment in patients with systemic lupus erythematous (SLE) is suboptimal. Although individual-level factors, including younger age and non-white race/ethnicity, have been implicated, contextual factors have not been explored. The aim of this study was to investigate the effect of contextual factors, including racial composition, socioeconomic status, and the concentration of health care resources, on adherence to HCQ among SLE patients enrolled in Medicaid.

METHODS

We identified SLE patients from 28 states in the US who enrolled in Medicaid (2000-2010) and in whom HCQ treatment was newly initiated (no use for ≥6 months). We required 12 months of continuous enrollment with complete drug dispensing data and measured adherence using the proportion of days covered (PDC). We identified individual-level variables from Medicaid, zip code-level, county-level and state-level sociodemographic variables from the American Community Survey, and health resources from Area Health Resources Files. We used 4-level hierarchical multivariable logistic regression models to examine the odds ratios (ORs) and 95% credible intervals (95% CrIs) of adherence (PDC ≥80%) versus nonadherence.

RESULTS

Among 10,268 patients with SLE in whom HCQ treatment was initiated, 15% were adherent to treatment. After we adjusted for individual-level characteristics, we observed lower odds of adherence among patients living in zip code areas with a higher percentage of black individuals (highest tertile OR 0.81 [95% CrI 0.69-0.96] versus lowest tertile). This association persisted after controlling for area-level educational attainment, percent below federal poverty level (FPL), urbanicity, and health care resources. We did not observe statistically significant associations with zip code-level percent Hispanic, percent white, education, or percent below FPL. The odds of adherence were higher in counties with more hospitals (OR 1.30 [95% CrI 1.07-1.58]).

CONCLUSION

Among Medicaid beneficiaries with SLE, we observed significant effects of racial composition and hospital concentration on HCQ adherence. Interventions that acknowledge and address contextual factors should be considered in order to reduce high rates of nonadherence in vulnerable populations.

Investigating lupus retention in care to inform interventions for disparities reduction: an observational cohort study

BACKGROUND

Systemic lupus erythematous (SLE) disproportionately impacts patients of color and socioeconomically disadvantaged patients. Similar disparities in HIV were reduced through a World Health Organization-endorsed Care Continuum strategy targeting "retention in care," defined as having at least two annual visits or viral load lab tests. Using similar definitions, this study aimed to examine predictors of lupus retention in care, to develop an SLE Care Continuum and inform interventions to reduce disparities. We hypothesized that Black patients and those residing in disadvantaged neighborhoods would have lower retention in care.

METHODS

Abstractors manually validated 545 potential adult cases with SLE codes in 2013-2014 using 1997 American College of Rheumatology (ACR) or 2012 Systemic Lupus Erythematosus International Collaborating Clinics (SLICC) criteria. We identified 397 SLE patients who met ACR or SLICC criteria for definite lupus, had at least one baseline rheumatology visit, and were alive through 2015. Retention in care was defined as having two ambulatory rheumatology visits or SLE labs (e.g., complement tests) during the outcome year 2015, analogous to HIV retention definitions. Explanatory variables included age, sex, race, ethnicity, smoking status, neighborhood area deprivation index (ADI), number of SLE criteria, and nephritis. We used multivariable logistic regression to test our hypothesis and model predictors of SLE retention in care.

RESULTS

Among 397 SLE patients, 91% were female, 56% White, 39% Black, and 5% Hispanic. Notably, 51% of Black versus 5% of White SLE patients resided in the most disadvantaged ADI neighborhood quartile. Overall, 60% met visit-defined retention and 27% met complement lab-defined retention in 2015. Retention was 59% lower for patients in the most disadvantaged neighborhood quartile (adjusted OR 0.41, CI 0.18, 0.93). No statistical difference was seen based on age, sex, race, or ethnicity. More SLE criteria and non-smoking predicted greater retention.

CONCLUSIONS

Disadvantaged neighborhood residence was the strongest factor predicting poor SLE retention in care. Future interventions could geo-target disadvantaged neighborhoods and design retention programs with vulnerable populations to improve retention in care and reduce SLE outcome disparities.