An epidemiologic analysis of end-stage lupus nephritis

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

OBJECTIVE

To estimate mortality and survival rates of SLE in a contemporary, population-based setting and assess potential influences by time, sex, ethnicity, classification criteria and age at diagnosis.

METHODS

We assessed mortality and survival in the Nor-SLE cohort, which includes all chart review-confirmed SLE cases resident in Southeast Norway (population 2.9 million) 1999-2017. Study end was at death, emigration or 1 October 2022. We defined juvenile SLE by age <16 years at diagnosis. For standardized mortality rate (SMR) estimates, we applied 15 population controls per case, all matched for age, sex, residency and ethnicity. We analysed survival by Kaplan-Meier and risk factors by Cox regression.

RESULTS

The Nor-SLE cohort included 1558 SLE cases, of whom 749 were incident and met the 2019 EULAR and ACR (2019-EA) classification criteria. SMR was increased to 1.8 (95% CI 1.6-2.2) in incident adult-onset SLE but did not differ between females and males. Survival rates at 5, 10, 15 and 20 years were lower in incident adult-onset SLE than in matched controls. In multivariable analysis, LN associated with decreased survival, while sex did not. Separate, long-term mortality analyses in the total Nor-SLE cohort showed that SMR peaked at 7.2 (95% CI 3.3-14) in juvenile-onset SLE (n = 93) and fell gradually by increasing age at SLE diagnosis.

CONCLUSION

This study shows persistence of a mortality gap between adult-onset SLE and controls at population level and provides indications of worryingly high mortality in juvenile-onset SLE.

Prevalence and outcomes of end-stage kidney disease in patients with systemic lupus erythematous: a population-based study

This study aims to examine the prevalence and outcomes of end-stage kidney disease (ESKD) among systemic lupus erythematosus (SLE) patients. SLE patients identified from the national administrative datasets were linked to the Australia and New Zealand Dialysis and Transplant Registry (ANZDATA) to identify the ESKD cases. Period prevalence of ESKD among SLE patients was calculated. The risk of developing ESKD by ethnicity was explored with Cox Proportional Hazards model. The adjusted hazard ratio (HR) of all-cause mortality for Māori, Pacific, Asian compared to European/others was estimated. Of the 2837 SLE patients, 210 (7.4%) developed ESKD. The average period prevalence of ESKD among SLE patients was 5.7%. Men had twice the prevalence rate of ESKD than women (10.0% vs 5.2%). Māori and Pacific had higher prevalence rate than Asian and European/others (9.4%, 9.8% vs 4.4% and 3.8%). The adjusted HR of developing ESKD for men compared to women was 3.37 (95% CI 1.62-7.02). The adjusted HR of developing ESKD for Māori and Pacific compared to European/others was 4.63 (95% CI 1.61-13.29) and 4.66 (95% CI 1.67-13.00), respectively. Compared to European/others, Māori had an HR of 2.17 (95% CI 1.18-4.00) for all-cause mortality. SLE patients had a high prevalence rate of ESKD. Men, Māori, and Pacific patients with SLE were more likely to develop ESKD. Māori patients with ESKD had poorer survival than other patients. Interventions are needed to reduce the risk of ESKD and to improve the survival of ESKD patients for the disadvantaged groups.

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.

Systemic Lupus Erythematosus: Targeted literature review of the epidemiology, current treatment and disease burden in the Asia Pacific region

OBJECTIVE

To understand the epidemiology, current treatment and disease burden of systemic lupus erythematosus (SLE) in the Asia Pacific region (APAC).

METHODS

A targeted literature review of published evidence on SLE in APAC was conducted, using the MEDLINE® database (2008-2018), conference proceedings and other supplementary sources.

RESULTS

The review identified 70 studies conducted in China (n=15), Japan (n=13), Taiwan (n=12), Korea (n=9), Australia (n=7), Hong Kong (n=6), Singapore (n=4), and multiple places within the APAC region (n=4). Incidence rates (per 100,000 per year) ranged from 0.9-8.4, while prevalence rates ranged from 3.7-127 (per 100,000); however, recent data was limited. Asian SLE patients were reported to have higher disease severity, activity (higher SLE disease activity index scores) and organ damage accrual; along with increased morbidity, mortality, and susceptibility to renal involvement compared with other ethnicities in APAC. The risk of developing SLE is higher in the Asian population. Routinely used SLE therapies included belimumab, hydroxychloroquine, cyclophosphamide, tacrolimus, azathioprine, mycophenolate mofetil, and corticosteroids; however, prescribing patterns varied across the region. Increased disease activity was associated with high economic burden and poor quality of life for SLE patients in APAC.

CONCLUSION

SLE remains a disease with a significant unmet medical need for an innovative therapy that is well-tolerated and effective for patients in APAC. Further evidence is required to better characterize the disease and fully capture the burden and impact of SLE in APAC. This review has highlighted where there is a paucity of data from patients across the APAC region.

Treatment patterns and medical cost of systemic lupus erythematosus patients in Japan: a retrospective claims database study

Aim: To describe the characteristics and medication treatment patterns, healthcare resource utilization (HRU), and associated costs in Japanese patients with systemic lupus erythematosus (SLE).Methods: Claims data from the Japan Medical Data Center (JMDC) database were used to identify patients with SLE-related claims from 2010 to 2017. Algorithms were developed to retrospectively categorize patients by disease severity, treatment experience, and SLE-related manifestations such as lupus nephritis and central nervous system lupus. Descriptive and multivariate analyses were used to describe treatment pattern and estimate HRU and associated costs for the SLE cohort overall and by disease severity and complications.Results: Among 4,733 eligible patients, 2,072 (43.8%) were treatment naïve, 2,214 (46.8%) were previously treated for SLE, and 447 (9.4%) did not receive any treatment. Mean (SD) age of the total SLE cohort was 45.2 (13.1) years and mean (SD) follow-up duration was 1,137.3 (758.0) d. Based on disease severity, 1,383 (29.2%) patients had mild, 2,619 (55.3%) patients had moderate, and 731 (15.4%) patients had severe SLE. Patients on glucocorticoids (both oral and parenteral) received add-on medications the most (35.5%, p < .001). Mean annual cost per SLE patient in the post-index period, inclusive of hospitalizations, outpatient visits, and pharmacy was ¥436,836; ¥1,010,772; and ¥2,136,780 for patients with mild, moderate, and severe SLE, respectively.Limitations: The database only captured information on patients up to 75 years of age. Due to the nature of the database, biases regarding conditions that attribute to the spectrum of SLE severity, flare incidences, or individual physical status cannot be ruled out.Conclusions: This study describes the treatment patterns and economic burden experienced by Japanese patients with SLE. The results highlight an unmet need to derive better treatment strategies for patients with SLE to effectively address the disease burden in Japan.

Trend of prevalence and incidence of systemic lupus erythematosus in South Korea, 2005 to 2015: a nationwide population-based study

BACKGROUND/AIMS

The aim of this study was to evaluate the trend of incidence and prevalence of systemic lupus erythematosus (SLE) in South Korea from 2005 to 2015.

METHODS

From 2005 to 2015, individuals with SLE were identified from the National Health Insurance database, which records information on almost all Koreans. SLE was defined according to the International Classification of Diseases, 10th revision (ICD-10), code M32. The incidence was calculated per 100,000 person-years. The prevalence was calculated per 100,000 people and stratified by year, age group, sex, region, and income.

RESULTS

The annual prevalence of SLE increased slightly from 21.25/100,000 people in 2005 to 35.45/100,000 people in 2015. In contrast, the annual incidence of SLE decreased slightly from 5.42/100,000 person-years in 2005 to 3.6/100,000 person-years in 2015. The prevalence and incidence of SLE were 10- and 6-fold higher in women than in men, respectively. The peak age of prevalence and incidence was 30 to 39 years in 2005; in 2015, the peak age of prevalence was 30 to 49 years and of incidence was 20 to 49 years. Regional variation was observed in both incidence and prevalence of SLE. Jeju province showed the highest prevalence of SLE (44.54/100,000 person-years), and Gwangju province showed the highest incidence of SLE (6.98/100,000 person-years) in 2015. The income status did not affect the prevalence or incidence of SLE except in patients without income who received medical aid.

CONCLUSION

The incidence of SLE has declined, but the prevalence has increased in Korea in recent years. Peak age of SLE trend to right shift in Korea.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Sex differences in clinical presentation of systemic lupus erythematosus

Objective

Systemic lupus erythematosus (SLE) predominantly affects women, but previous studies suggest that men with SLE present a more severe disease phenotype. In this study, we investigated a large and well-characterized patient group with the aim of identifying sex differences in disease manifestations, with a special focus on renal involvement.

Methods

We studied a Swedish multi-center SLE cohort including 1226 patients (1060 women and 166 men) with a mean follow-up time of 15.8 ± 13.4 years. Demographic data, disease manifestations including ACR criteria, serology and renal histopathology were investigated. Renal outcome and mortality were analyzed in subcohorts.

Results

Female SLE patients presented more often with malar rash (p < 0.0001), photosensitivity (p < 0.0001), oral ulcers (p = 0.01), and arthritis (p = 0.007). Male patients on the other hand presented more often with serositis (p = 0.0003), renal disorder (p < 0.0001), and immunologic disorder (p = 0.04) by the ACR definitions. With regard to renal involvement, women were diagnosed with nephritis at an earlier age (p = 0.006), while men with SLE had an overall higher risk for progression into end-stage renal disease (ESRD) with a hazard ratio (HR) of 5.1 (95% CI, 2.1–12.5). The mortality rate among men with SLE and nephritis compared with women was HR 1.7 (95% CI, 0.8–3.8).

Conclusion

SLE shows significant sex-specific features, whereby men are affected by a more severe disease with regard to both renal and extra-renal manifestations. Additionally, men are at a higher risk of developing ESRD which may require an increased awareness and monitoring in clinical practice.

Sex Differences in Health Care Utilization, End-Stage Renal Disease, and Mortality Among Medicaid Beneficiaries With Incident Lupus Nephritis

OBJECTIVE

While systemic lupus erythematosus and lupus nephritis (LN) disproportionately affect females, previous studies suggest that males may experience poorer outcomes. We undertook this study to investigate sex differences in health care utilization, end-stage renal disease (ESRD), and mortality among patients with LN receiving Medicaid, public insurance for low-income individuals.

METHODS

Within the Medicaid Analytic eXtract (MAX) from 29 states (from 2000 to 2010), we used billing claims to identify individuals ages 5-65 years with incident LN (positive predictive value 80%). MAX data were linked to the US Renal Data System to determine ESRD and to Social Security Death Index files to determine death. We estimated adjusted incidence rate ratios (IRRs) by sex for health care utilization using Poisson regression, and we used multivariable proportional hazards models to compare risks of ESRD and death by sex.

RESULTS

Of 2,750 patients with incident LN, 283 (10%) were male. The mean ± SD follow-up period for both sexes was 3.1 ± 2.3 years. The mean ± SD age was 29.6 ± 13.9 years among females and 24.7 ± 14.1 years among males (P < 0.01). Males had fewer outpatient visits (IRR 0.88 [95% confidence interval (95% CI) 0.80-0.97]) and fewer emergency department visits (IRR 0.75 [95% CI 0.63-0.90]). The 5-year cumulative incidence of ESRD was 22.3% in males and 21.2% in females. The 5-year cumulative incidence of death was 9.4% in males and 9.8% in females. Comparing males to females, there were no sex differences in ESRD (subdistribution hazard ratio [HR] 1.05 [95% CI 0.76-1.45]) or death (HR 0.81 [95% CI 0.47-1.35]).

CONCLUSION

In this cohort of patients with incident LN, ESRD and mortality were extremely high overall but were not increased among males compared to females. In this vulnerable population, biologic and health care utilization differences by sex may not significantly affect outcomes.

Epidemiology of systemic lupus erythematosus

INTRODUCTION

Systemic lupus erythematosus (SLE) is a disease distributed worldwide, which occurs in both genders, and across racial/ethnic and age groups; however, higher rates are observed in adults, in women and in non-Caucasians. Genetic, environmental, sociodemographic and methodological issues are responsible not only for these differences but for the variable course and outcome of the disease. Non-Caucasians have a more severe disease with a higher risk for early mortality and damage accrual. Males also have a more severe disease; however, a negative impact of male gender on lupus outcomes has not been firmly established. Childhood-onset is associated with a more severe disease; moreover, it is also associated with higher damage and diminished survival; finally, late-onset lupus is mild but it is associated with higher damage accrual and a diminished survival. Areas covered: In this review, we discuss the incidence and prevalence of SLE, the impact of age, gender and race/ethnicity in SLE and in the survival of those affected. Expert commentary: Age, gender and race/ethnicity impact disease expression in SLE patients; despite improvements in survival, mortality in SLE remains almost three times higher than in the general population.

The global burden of SLE: prevalence, health disparities and socioeconomic impact

Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease that can potentially lead to serious organ complications and even death. Its global burden - in terms of incidence and prevalence, differential impact on populations, economic costs and capacity to compromise health-related quality of life - remains incompletely understood. The reported worldwide incidence and prevalence of SLE vary considerably; this variation is probably attributable to a variety of factors, including ethnic and geographic differences in the populations being studied, the definition of SLE applied, and the methods of case identification. Despite the heterogeneous nature of the disease, distinct patterns of disease presentation, severity and course can often be related to differences in ethnicity, income level, education, health insurance status, level of social support and medication compliance, as well as environmental and occupational factors. Given the potential for the disease to cause such severe and widespread organ damage, not only are the attendant direct costs high, but these costs are sometimes exceeded by indirect costs owing to loss of economic productivity. As an intangible cost, patients with SLE are, not surprisingly, likely to endure considerably reduced health-related quality of life.

Renal damage in systemic lupus erythematosus: a comparative analysis of different age groups

Renal damage in systemic lupus erythematosus: a comparative analysis of different age groups A Mak, CC Mok, WP Chu, CH To, SN Wong and TC Au Please note that the following pdf is a corrected version of the article which appears in the printed version of Lupus 16/1. An Erratum will also appear in print in Lupus; 16(2). The corrected line can be found in the abstract. It was changed from: Patients were categorized into childhood (age ≥6 years), adult (between 16 and 50 years) or late onset (≥50 years) SLE. To: Patients were categorized into childhood (age 16 years), adult (between 16 and 50 years) or late onset (50 years) SLE.The objective of this study was to compare the frequency and severity of renal damage in systemic lupus erythematosus (SLE) with regard to the age of disease onset. Among 287 patients with new onset SLE diagnosed between 1991 and 2003 in our hospital, we identified those who fulfilled the American College of Rheumatology (ACR) criteria for renal involvement. Patients were categorized into childhood (age <6 years), adult (between 16 and 50 years) or late onset (≥50 years) SLE. Clinical presentation of renal disease and cumulative renal damage as assessed by the renal domain of the Systemic Lupus International Collaborating Clinics/ACR damage index (SDI) were compared. A linear regression model was constructed to study the effect of age on renal damage. One-hundred and forty-nine patients were studied (134 women and 15 men), including 28 childhood, 107 adult and 14 late onset SLE patients. The mean age of SLE onset was 29.7 ± 14 years. The prevalence of renal disease was 53% in childhood onset, 50% in adult onset and 58% in late onset SLE patients (P = 0.66). At renal disease presentation, late onset SLE patients had significantly lower creatinine clearance and were more likely to be hypertensive. Histological classes of nephritis and initial treatment response, however, did not differ significantly among the patients. After a mean observation of 80.3 months, 32 (21%) patients developed renal damage (renal SDI ≥ 1). Late onset SLE patients had accrued more renal damage than the others. In a multiple regression model, age was not a significant determinant of renal damage after adjustment for baseline renal parameters, duration of renal disease, use of cyclophosphamide and initial treatment response. We concluded that the prevalence of renal disease was similar among SLE patients of different ages of onset. Late onset SLE patients had accrued more renal damage but age did not correlate with renal damage after adjustment for various clinical parameters.

Incidence of End-Stage Renal Disease Among Newly Diagnosed Systemic Lupus Erythematosus Patients: The Georgia Lupus Registry

OBJECTIVE

To estimate and identify factors associated with the incidence of all-cause end-stage renal disease (ESRD) among newly diagnosed systemic lupus erythematosus (SLE) patients.

METHODS

Data from a national registry of treated ESRD were linked to data from a lupus registry of SLE patients who were newly diagnosed and living in Atlanta, Georgia, 2002-2004 (median followup 7.8 years). Cumulative incidence and incidence rates (ESRD treatment initiations per 1,000 patient-years) were calculated, and age- and race-adjusted Poisson models were used to calculate incidence rate ratios (IRRs).

RESULTS

Among 344 newly diagnosed SLE patients, 29 initiated ESRD treatment over 2,603.8 years of followup. Incidence rates were 13.8 (95% confidence interval [95% CI] 9.4-20.3) among black patients and 3.3 (95% CI 0.8-13.0) among white patients, per 1,000 patient-years; corresponding 5-year cumulative incidence was 6.4% and 2.5% among black and white patients, respectively. Lupus nephritis documented prior to 2005, which occurred in 80% of those who progressed to ESRD, was the strongest risk factor for incident ESRD (IRR 6.7 [95% CI 2.7-16.8]; incidence rate 27.6 per 1,000 patient-years). Results suggested that patients who were black versus white (IRR 3.9 [95% CI 0.9-16.4]) or <18 years old (versus ≥30 years old) at diagnosis (IRR 2.1 [95% CI 0.9-5.3]) may be more likely to progress to ESRD, but incidence did not differ by sex or other characteristics.

CONCLUSION

The incidence of all-cause ESRD among patients with a recent diagnosis of SLE is high in Georgia. Interventions to decrease ESRD incidence among newly diagnosed SLE patients should target young and black patients, as well as patients with lupus nephritis.

Long-term renal outcomes in a cohort of 1814 Chinese patients with biopsy-proven lupus nephritis

In the present study, we observed the renal outcomes in a cohort of 1814 Chinese patients with biopsy-proven lupus nephritis (LN) and evaluated the risk factors associated with poor renal prognosis. The 5 -, 10 -, 15 - and 20-year renal survival rates were 93.1%, 87.9%, 81.0% and 68.3%, respectively. Gender, LN duration, mean arterial pressure (MAP), proteinuria, serum creatinine, haemoglobin and pathological classification at the time of biopsy were independent risk factors for end-stage renal disease (ESRD). The long-term renal outcomes of patients with class II LN were unfavorable as opposed to those with class V. Additionally, the time-average proteinuria (TA-Pro) and the time-average mean arterial pressure (TA-MAP) during the follow-up were important risk factors for ESRD, with better predictive values than the baseline proteinuria and MAP. The results underscore the need for proteinuria and blood pressure control during follow-up in patients with LN; proteinuria levels should be controlled at least to < 1.0 g/24 h, and optimally to < 0.5 g/24 h; MAP should not exceed 96.5 mmHg. More attention should be paid to class II LN and emphasis should be placed on recurrence prevention of class II LN.

Incidence and prevalence of lupus in Buenos Aires, Argentina: a 11-year health management organisation-based study

Objectives

Studies regarding the epidemiology of systemic lupus erythematosus (SLE) are lacking in Argentina. Our purpose was to estimate the incidence and prevalence of SLE in a university hospital-based health management organisation in Buenos Aires (HIMCP).

Methods

For incidence calculation, the population at risk included all adult members of the HIMCP, with continuous affiliation for at least 1 year from January 1998 to January 2009. Each person was followed until he/she voluntarily left the HIMCP, death or finalisation of the study. Multiple methods for case finding were used to ensure complete ascertainment: (a) patients with problem SLE, undifferentiated autoimmune disease or mixed connective tissue disease in the Computer-based Patient Record System, (b) patients with positive antinuclear antibody test, anti-Sm antibodies and/or anti-dsDNA antibodies in the laboratory database and (c) patients who consumed hydroxichloroquine, chloroquine, azathioprine, cyclophosphamide, mycophenolate, cyclosporine or rituximab, from the administrative HIMCP drugs database. Medical records of all patients found were reviewed, and only patients fulfilling ACR criteria for SLE were included. Global and gender incidence rate (IR) was calculated. Prevalence was estimated on 1 January 2009, and the denominator population was the number of active members >18 years at that date (n=127 959).

Results

In the study period, 68 patients developed SLE. The observed IR (per 100 000 person-years, (CI 95%)) was 6.3 (4.9 to 7.7) for total population; 8.9 (CI 6.6 to 11.2) for women and 2.6 (1.2 to 3.9) for men. On 1 January 2009, 75 prevalent cases were identified. Prevalence rates (cases per 100 000 habitants, (CI 95%)) were 58.6 (46.1 to 73.5) for total population; 83.2 (63.9 to 106.4) for women and 23 (CI 11.9 to 40.1) for men.

Conclusions

SLE incidence and prevalence rates in Argentina are in agreement with those of other studies from different parts of the world.

Asian ethnicity in systemic lupus erythematosus: an Australian perspective

Ethnic differences in both disease susceptibility and expression have been noted in systemic lupus erythematosus (SLE). This review focuses on the evidence of disparities between SLE patients of Asian and Caucasian descent, the two predominant ethnic groups affected by SLE in the Australian context. While epidemiological studies suggest higher rates of SLE among Asian patients, multi-ethnic cohort studies have allowed direct comparison of disease characteristics between different ethnic groups. Such studies suggest that Asians are affected by more severe SLE across several disease parameters, including increased renal involvement, autoantibody positivity, disease activity and damage accumulation. As delineation of these disparities becomes clearer, uncovering the biological basis of such differences poses a significant opportunity to progress understanding of SLE pathogenesis. Understanding ethnic variation in disease provides a platform for an individualised approach to risk assessment, monitoring and management of SLE.

Incidence of progression from newly diagnosed systemic lupus erythematosus to end stage renal disease and all-cause mortality: a nationwide cohort study in Taiwan

AIM

End-stage renal disease (ESRD) is a common finding in systemic lupus erythematosus (SLE) and may contribute to mortality. The purpose of the study was to investigate the incidence of ESRD and all-cause mortality and their risk factors in patients newly diagnosed with SLE in Taiwan.

METHODS

This nationwide cohort study used data from the National Health Insurance Research Database. We identified 4130 newly diagnosed SLE patients at risk for ESRD during 2000-2002; among them, 103 developed ESRD by the end of 2008. Additional 412 age- and sex-matched incident ESRD non-SLE patients served as controls for the survival analysis.

RESULTS

Of the newly diagnosed SLE patients, 2.5% developed ESRD. Age (adjusted hazards ratio [HR] 0.66 for each 1-year increase; 95% confidence interval [CI] 0.47-0.94) and male gender (adjusted HR 2.24; 95% CI 1.4-3.6) were significantly associated with ESRD development. Survival analysis conducted after ESRD development revealed a higher mortality risk among the older patients (HR 1.04; 95% CI 1.02-1.05). Survival analysis in the younger population (age < 40 years) after ESRD development revealed a significant mortality risk among SLE patients (HR 2.73; 95% CI 1.22-6.07).

CONCLUSION

In the follow-up of newly diagnosed SLE patients in Taiwan, younger age and male gender were risk factors for ESRD development. After entering ESRD, these risk factors had different impacts on mortality. Despite the overall improvement in care of patients with lupus nephritis, survival is still poorer in the younger age population.

Epidemiology and sociodemographics of systemic lupus erythematosus and lupus nephritis among US adults with Medicaid coverage, 2000-2004

OBJECTIVE

Systemic lupus erythematosus (SLE) and lupus nephritis (LN) disproportionately affect individuals who are members of racial/ethnic minority groups and individuals of lower socioeconomic status (SES). This study was undertaken to investigate the epidemiology and sociodemographics of SLE and LN in the low-income US Medicaid population.

METHODS

We utilized Medicaid Analytic eXtract data, with billing claims from 47 states and Washington, DC, for 23.9 million individuals ages 18-65 years who were enrolled in Medicaid for >3 months in 2000-2004. Individuals with SLE (≥3 visits >30 days apart with an International Classification of Diseases, Ninth Revision [ICD-9] code of 710.0) and with LN (≥2 visits with an ICD-9 code for glomerulonephritis, proteinuria, or renal failure) were identified. We calculated SLE and LN prevalence and incidence, stratified by sociodemographic category, and adjusted for number of American College of Rheumatology (ACR) member rheumatologists in the state and SES using a validated composite of US Census variables.

RESULTS

We identified 34,339 individuals with SLE (prevalence 143.7 per 100,000) and 7,388 (21.5%) with LN (prevalence 30.9 per 100,000). SLE prevalence was 6 times higher among women, nearly double in African American compared to white women, and highest in the US South. LN prevalence was higher among all racial/ethnic minority groups compared to whites. The areas with lowest SES had the highest prevalence; areas with the fewest ACR rheumatologists had the lowest prevalence. SLE incidence was 23.2 per 100,000 person-years and LN incidence was 6.9 per 100,000 person-years, with similar sociodemographic trends.

CONCLUSION

In this nationwide Medicaid population, there was sociodemographic variation in SLE and LN prevalence and incidence. Understanding the increased burden of SLE and its complications in this low-income population has implications for resource allocation and access to subspecialty care.

Systematic review of the epidemiology of systemic lupus erythematosus in the Asia-Pacific region: prevalence, incidence, clinical features, and mortality

OBJECTIVE

Systemic lupus erythematosus (SLE), a chronic multisystem autoimmune disease with a wide spectrum of manifestations, shows considerable variation across the globe, although there is little evidence to indicate its relative prevalence in Asia. This review describes its prevalence, severity, and outcome across countries in the Asia-Pacific region.

METHODS

We conducted a systematic literature search using 3 groups of terms (SLE, epidemiology, and Asia-Pacific countries) of EMBase and PubMed databases and non-English language resources, including Chinese Wanfang, Korean KMbase, Korean College of Rheumatology, Japana Centra Revuo Medicina, Taiwan National Digital Library of Theses and Dissertations, and Taiwanese, Thai, and Vietnamese journals.

RESULTS

The review showed considerable variation in SLE burden and survival rates across Asia-Pacific countries. Overall crude incidence rates (per 100,000 per year) ranged from 0.9-3.1, while crude prevalence rates ranged from 4.3-45.3 (per 100,000). Higher rates of renal involvement, one of the main systems involved at death, were observed for Asians (21-65% at diagnosis and 40-82% over time) than for whites. While infections and active SLE were leading causes of death, a substantial proportion (6-40%) of deaths was due to cardiovascular involvement. The correlation between the Human Development Index and 5-year survival was 0.83.

CONCLUSION

This review highlights the need to closely monitor Asian SLE patients in Asian countries for renal and cardiovascular involvement, especially those who may not receive proper treatment and are therefore at greater risk of severe disease. We hope this will encourage further research specific to this region and lead to improved clinical management.

Age- and gender-related long-term renal outcome in patients with lupus nephritis

Objective: To investigate age- and gender-related long-term renal outcome in patients with lupus nephritis (LN).

Methods: This is a retrospective, chart review study of patients with LN at Chang Gung Memorial Hospital, Kaohsiung, between January 1986 and June 2004. All had undergone a renal biopsy that showed LN. The end point of outcome was chronic renal insufficiency (CRI), which was defined as ‘doubling of baseline serum creatinine lasting for at least 6 months with a value at least 2 mg/dl.’ The patients were categorized by age tertiles and gender. A 5-year survival curve was constructed to study the effect of age and gender on the outcome.

Results: In total, 121 sets of patient data were evaluated. The study group included 104 women and 17 men. Of the study patients, 26 (21%) developed CRI after 5 years of follow-up. There was no significant difference among age groups in developing CRI ( p = 0.23). In terms of gender, men had worse long-term renal outcome ( p = 0.004) than women.

Conclusions: The long-term renal outcome of the LN patients did not differ among age groups, but was worse in men.

Epidemiology of systemic lupus erythematosus in Asia

In this paper we aim to review the prevalence, incidence and disease presentation of lupus patients in Asian populations. The database of the National Library of Medicine (MEDLINE) through PUBMED up to September 2009 was searched for relevant articles using the search terms 'systemic lupus erythematosus', 'epidemiology', and 'Asia'. Articles on lupus prevalence, incidence, and clinical manifestations were retrieved and their bibliographies further screened for relevant articles. Proceedings of national, regional, and international rheumatology and SLE conferences were likewise searched for relevant abstracts. Retrieval rate of relevant articles was approximately 80%. Prevalence and incidence figures are expressed per 100,000 populations. Among the articles reviewed, epidemiologic information was usually obtained through population surveys or hospital cohorts. Prevalence data are available from 24 countries, and generally fall within 30-50/100,000 population. However, one survey showed a higher prevalence of 70 (Shanghai), while three others showed a lower prevalence of 3.2-19.3 (India, Japan, Saudi Arabia). Only three countries have recorded incidence rates and these varied from 0.9 to 3.1 per annum. Thirty articles from 21 countries describe lupus disease presentation. Common manifestations include mucocutaneous lesions (seen in 52-98% of patients) and arthritis/musculoskeletal complaints (36-95%). Antinuclear antibodies were generally positive in 89-100% of patients, except for two studies. Renal involvement ranged from 18% to 100% with most articles reporting this in >50% of their patients. Discoid lesions, serositis, and neurologic involvement were the least frequently seen symptoms. There is varying epidemiologic information regarding systemic lupus erythematosus among countries in Asia. Prevalence rates usually fall within 30-50/100,000 population. Incidence rates, as reported from three countries, varied from 0.9/100,000 to 3.1% per annum. It is difficult to make generalizations about how the epidemiologic character of the disease varies from country to country. However, similarities in disease manifestations can be observed. .

Tuberculosis as a risk factor for systemic lupus erythematosus: results of a nationwide study in Taiwan

A previous study, with relatively small number of patients, showed that prior Mycobacterium tuberculosis (TB) may precipitate SLE in patients from endemic areas. The purpose of the study was to investigate the relationship between prior TB infection and systemic lupus erythematosus (SLE) from the National Health Insurance Research Database (NHIRD) in Taiwan. Cases of SLE and TB were identified from the NHIRD with corresponding ICD-9 codes 710.0 and 011-018, respectively, from January 2000 to December 2008. A total of 2,721 cases of SLE and 10,823 control subjects were included in data analysis. The average annual incidence rate was 8.1 per 100,000. The annual incidence rates of SLE decreased from 6.38 per 100,000 to 2.55 per 100,000 during 2000-2008. Compared with the control subjects, SLE patients were more likely to be white collar workers (P = 0.0005), reside in highly urbanized areas (P = 0.0140), and have higher incomes (P = 0.0088). TB was much more prevalent in SLE patients than in the control subjects (1.8 vs. 0.9%, P < 0.001). The mean time interval between diagnosis of TB and SLE was 45.58 ± 39.0 months. On multivariate analysis, TB was the greatest potential risk factor for precipitating SLE (OR = 2.11, 95% CI = 1.49-3.00). In addition, patients with co-existing TB and DM had a higher risk of SLE than the control group (OR = 3.91, 95% CI 1.84-8.31). In conclusion, this study suggests that there is an increased risk of precipitating SLE among patients with TB in Taiwan from a nationwide health insurance research dataset. Mycobacterial infections could trigger autoimmune diseases in experimental studies. Furthermore, a study with relatively small number of patients revealed that prior TB may precipitate SLE in patients from endemic areas. There is an increased risk of precipitating SLE among patients with TB in Taiwan from a nationwide health insurance research dataset during a 9-year period.

Decreased incidence of lupus nephritis in northern Norway is linked to increased use of antihypertensive and anticoagulant therapy

BACKGROUND

Lupus nephritis (LN) remains a severe complication in systemic lupus erythematosus (SLE). Over the last decade, antiphospholipid antibodies have become a part of SLE classification criteria, and awareness of cardiovascular morbidity and its risk factors in SLE has increased. This study investigated the potential effect of these alterations on the presentation and severity of LN.

METHODS

This is an observational study of two subsequent SLE inception cohorts based on 1982 American College of Rheumatology (acr) classification criteria (82acr; n=87, enrolled 1978-95) and the updated version in 1997 (97acr: n=62, enrolled 1996-2006). Annual incidence rates (AIR), point prevalence, clinical and histological features, and outcome of LN (defined as proteinuria with urinary casts and/or haematuria) were compared between both cohorts.

RESULTS

Between 1978 and 2006, the AIR for LN decreased from 0.7 to 0.45/100 000, while LN prevalence rose from 7 to 14/100 000. The relative risk reduction in the 97acr for early- and late-onset LN (> 3 months after SLE diagnosis) was 39% and 42%, respectively. Patients developing LN in the 97acr cohort (97LN+; n=11) had similar demographics, more often low avidity anti-dsDNA antibodies (Ab) and/or anti-cardiolipin Ab at SLE diagnosis, lower proteinuria and diastolic blood pressure, and similar histological findings to those in the 83acr cohort (82LN +; n=28). Following LN diagnosis, more 97LN + patients received pulse corticosteroids (55% vs. 7%), anticoagulants (46% vs. 4%) and antihypertensive drugs (46% vs. 11%). Three 82LN+ patients (11%) developed end-stage renal disease versus none in 97LN + during a 10-year follow-up.

CONCLUSIONS

Early detection of low avidity anti-dsDNA and antiphospholipid antibodies, probably in combination with early use of protective cardiovascular measures from SLE diagnosis onwards may contribute to reduced incidence and improved renal survival in LN.

Identification and validation of lupus nephritis cases using administrative data

Large administrative databases such as Medicaid billing databases could be used to study care and outcomes of lupus nephritis if these patients could be correctly identified from claims data. We aimed to develop and validate an algorithm for the correct identification of cases of lupus nephritis using ICD-9 billing codes. We used the Research Patient Data Resource query tool at our institution to identify patients with potential lupus nephritis. We compared four ICD-9 code based strategies, identifying patients seen between 2000 and 2007 with Medicaid medical insurance with greater than two claims for a diagnosis of SLE (ICD-9 code 710.0) and a combination of greater than two nephrologist visits and/or renal ICD-9 codes. We assessed performance using the positive predictive value. Two hundred and thirty four subjects were identified and medical records reviewed. Our third strategy, based on a combination of lupus and renal ICD-9 codes and nephrologist encounter claims, had the highest positive predictive value (88%) for the identification of patients with lupus nephritis. This strategy may offer a sound method of identifying patients with lupus nephritis for health services research in addition to serving as a model for using claims data as a way to better understand rare diseases such as lupus.

Systemic lupus erythematosus in men: a retrospective analysis in a Veterans Administration Healthcare System population

Systemic lupus erythematosus (SLE), a connective tissue disease of unknown etiology, is generally considered to occur in women of child-bearing age and to be uncommon among men . Because of the female predominance in most studies, less is known about the disease in men. To begin to better understand lupus in men, we retrospectively analyzed all the SLE patients from all the hospitals in the Department of Veterans Affairs (VA) system, a population that is predominantly male. Between 1987 and 1996, 2614 SLE patients were retrieved from the VA databank; 2144 were male, making this the largest group of male patients with SLE reported in United States of America. Age, racial and geographic distribution, comorbidities, and mortality of the SLE patients are reported. This study suggests that SLE men in this population are older at onset of disease, have different comorbidities, and have a higher mortality at 1 year than women with SLE. These findings suggest that men with SLE have a more complex clinical course than women, although the data do not illuminate whether the comorbidities are due to or coincident with SLE. On the basis of these data, practitioners are reminded to consider SLE in the differential diagnosis for older men and be attentive to the frequent presence of comorbidities such as cardiac ischemia and neoplasms. Because of the identified regional variations in demographics, comorbidities, and mortality, this study suggests the need for future SLE studies to include data from multiple geographic areas.

Ethnic and geographical differences in systemic lupus erythematosus: an overview

Systemic lupus erythematosus (SLE) is one of the most heterogeneous autoimmune disorders known. There is production of a variety of autoantibodies and patients present with a wide range of symptoms due to multiple organ involvement by the disease process. The underlying cause is not fully understood but it may involve genetic and environmental factors. It is interesting to note that while SLE is found worldwide, it is more commonly found in some countries, and within a country certain ethnic groups appear to be more susceptible to develop this condition than others. Additionally, the presentation and course of SLE appear highly variable between patients of different ethnic origins. For example, African-Americans and Orientals are believed to have a more severe disease than Caucasian whites. But are these ethnic and geographical differences real? If yes, they may provide investigators insight into the underlying pathoaetiology of this condition and pave the way to future research directions in lupus.

The prevalence and incidence of biopsy-proven lupus nephritis in the UK: Evidence of an ethnic gradient

OBJECTIVE

Renal involvement is a major complication of systemic lupus erythematosus (SLE) and is a strong determinant of morbidity and mortality. There have been no previous studies of the epidemiology of lupus nephritis. Our aim was to establish the prevalence and incidence of biopsy-proven lupus nephritis in the northwest of England in 2001 and to examine the influence of age, sex, and ethnicity.

METHODS

Adults (age 18 years and older) with biopsy-proven lupus nephritis were identified from 5 sources: renal biopsy databases, dialysis/transplant databases, nephrologists' patients, clinic lists, and lupus patient groups. The denominator data for the northwest of England were ascertained from the 2001 census.

RESULTS

We identified 208 cases of biopsy-proven lupus nephritis (176 women, 32 men): the overall prevalence was 4.4 per 100,000 population (95% confidence interval [95% CI] 3.8-5.0), 7.1 per 100,000 (95% CI 6.1-8.2) in women, and 1.4 per 100,000 (95% CI 1.0-2.0) in men. The prevalence was significantly higher among women in the ethnic subgroups: 110.3 per 100,000 population (95% CI 55.0-197.3) in Chinese patients, 99.2 per 100,000 (95% CI 55.5-163.6) in Afro-Caribbean, 21.4 per 100,000 (95% CI 12.0-35.2) in Indo-Asian (Asians from the Indian subcontinent), and 5.6 per 100,000 (95% CI 4.7-6.7) in white patients. The overall annual incidence rate was 0.40 per 100,000 population per year (95% CI 0.24-0.63), with a rate of 0.68 (95% CI 0.40-1.10) in women and 0.09 (95% CI 0.01-0.32) in men. Capture-recapture methods did not suggest any additional cases.

CONCLUSION

This first estimate of the prevalence and incidence of biopsy-proven lupus nephritis demonstrates dramatic differences in prevalence according to ethnicity, with an increasing gradient from the white to the Indo-Asian, Afro-Caribbean, and Chinese populations.

Epidemiology of systemic lupus erythematosus: a comparison of worldwide disease burden

Systemic lupus erythematosus (SLE) is a disease of multifactorial etiology. Quantifying the burden of SLE across different countries can clarify the role of genetic, environmental and other causative factors in the natural history of the disease, and to understand its clinical and societal consequences. The aim of this study is to summarize data on SLE incidence and prevalence in the USA, Europe, Asia, and Australia. An extensive review of electronic resources (PubMed and MedLine) and medical journals was conducted to identify published studies on SLE incidence and prevalence over the period of 1950-early 2006. Researchers in the countries of interest provided additional information on the epidemiology of SLE. The incidence and prevalence of SLE varies considerably across the countries. The burden of the disease is considerably elevated among non-white racial groups. There is a trend towards higher incidence and prevalence of SLE in Europe and Australia compared to the U.S.A. In Europe, the highest prevalence was reported in Sweden, Iceland and Spain. There are marked disparities in SLE rates worldwide. This variability may reflect true differences across populations, or result from methodological differences of studies. The true geographic, racial, and temporal differences in SLE incidence and prevalence may yield important clues to the etiology of disease.

Epidemiology of systemic lupus erythematosus: a comparison of worldwide disease burden

Systemic lupus erythematosus (SLE) is a disease of multifactorial etiology. Quantifying the burden of SLE across different countries can clarify the role of genetic, environmental and other causative factors in the natural history of the disease, and to understand its clinical and societal consequences. The aim of this study is to summarize data on SLE incidence and prevalence in the USA, Europe, Asia, and Australia. An extensive review of electronic resources (PubMed and MedLine) and medical journals was conducted to identify published studies on SLE incidence and prevalence over the period of 1950-early 2006. Researchers in the countries of interest provided additional information on the epidemiology of SLE. The incidence and prevalence of SLE varies considerably across the countries. The burden of the disease is considerably elevated among non-white racial groups. There is a trend towards higher incidence and prevalence of SLE in Europe and Australia compared to the USA. In Europe, the highest prevalence was reported in Sweden, Iceland and Spain. There are marked disparities in SLE rates worldwide. This variability may reflect true differences across populations, or result from methodological differences of studies. The true geographic, racial, and temporal differences in SLE incidence and prevalence may yield important clues to the etiology of disease.

Epidemiology of systemic lupus erythematosus: a comparison of worldwide disease burden

Systemic lupus erythematosus (SLE) is a disease of multifactorial etiology. Quantifying the burden of SLE across different countries can clarify the role of genetic, environmental and other causative factors in the natural history of the disease, and to understand its clinical and societal consequences. The aim of this study is to summarize data on SLE incidence and prevalence in the USA, Europe, Asia, and Australia. An extensive review of electronic resources (PubMed and MedLine) and medical journals was conducted to identify published studies on SLE incidence and prevalence over the period of 1950-early 2006. Researchers in the countries of interest provided additional information on the epidemiology of SLE. The incidence and prevalence of SLE varies considerably across the countries. The burden of the disease is considerably elevated among non-white racial groups. There is a trend towards higher incidence and prevalence of SLE in Europe and Australia compared to the USA. In Europe, the highest prevalence was reported in Sweden, Iceland and Spain. There are marked disparities in SLE rates worldwide. This variability may reflect true differences across populations, or result from methodological differences of studies. The true geographic, racial, and temporal differences in SLE incidence and prevalence may yield important clues to the etiology of disease.

Epidemiology of systemic lupus erythematosus: a comparison of worldwide disease burden

Systemic lupus erythematosus (SLE) is a disease of multifactorial etiology. Quantifying the burden of SLE across different countries can clarify the role of genetic, environmental and other causative factors in the natural history of the disease, and to understand its clinical and societal consequences. The aim of this study is to summarize data on SLE incidence and prevalence in the USA, Europe, Asia, and Australia. An extensive review of electronic resources (PubMed and MedLine) and medical journals was conducted to identify published studies on SLE incidence and prevalence over the period of 1950-early 2006. Researchers in the countries of interest provided additional information on the epidemiology of SLE. The incidence and prevalence of SLE varies considerably across the countries. The burden of the disease is considerably elevated among non-white racial groups. There is a trend towards higher incidence and prevalence of SLE in Europe and Australia compared to the USA. In Europe, the highest prevalence was reported in Sweden, Iceland and Spain. There are marked disparities in SLE rates worldwide. This variability may reflect true differences across populations, or result from methodological differences of studies. The true geographic, racial, and temporal differences in SLE incidence and prevalence may yield important clues to the etiology of disease.

Epidemiology of systemic lupus erythematosus: a comparison of worldwide disease burden

Systemic lupus erythematosus (SLE) is a disease of multifactorial etiology. Quantifying the burden of SLE across different countries can clarify the role of genetic, environmental and other causative factors in the natural history of the disease, and to understand its clinical and societal consequences. The aim of this study is to summarize data on SLE incidence and prevalence in the USA, Europe, Asia, and Australia. An extensive review of electronic resources (PubMed and MedLine) and medical journals was conducted to identify published studies on SLE incidence and prevalence over the period of 1950-early 2006. Researchers in the countries of interest provided additional information on the epidemiology of SLE. The incidence and prevalence of SLE varies considerably across the countries. The burden of the disease is considerably elevated among non-white racial groups. There is a trend towards higher incidence and prevalence of SLE in Europe and Australia compared to the USA. In Europe, the highest prevalence was reported in Sweden, Iceland and Spain. There are marked disparities in SLE rates worldwide. This variability may reflect true differences across populations, or result from methodological differences of studies. The true geographic, racial, and temporal differences in SLE incidence and prevalence may yield important clues to the etiology of disease.

Epidemiology of systemic lupus erythematosus: a comparison of worldwide disease burden

Systemic lupus erythematosus (SLE) is a disease of multifactorial etiology. Quantifying the burden of SLE across different countries can clarify the role of genetic, environmental and other causative factors in the natural history of the disease, and to understand its clinical and societal consequences. The aim of this study is to summarize data on SLE incidence and prevalence in the USA, Europe, Asia, and Australia. An extensive review of electronic resources (PubMed and MedLine) and medical journals was conducted to identify published studies on SLE incidence and prevalence over the period of 1950-early 2006. Researchers in the countries of interest provided additional information on the epidemiology of SLE. The incidence and prevalence of SLE varies considerably across the countries. The burden of the disease is considerably elevated among non-white racial groups. There is a trend towards higher incidence and prevalence of SLE in Europe and Australia compared to the USA. In Europe, the highest prevalence was reported in Sweden, Iceland and Spain. There are marked disparities in SLE rates worldwide. This variability may reflect true differences across populations, or result from methodological differences of studies. The true geographic, racial, and temporal differences in SLE incidence and prevalence may yield important clues to the etiology of disease.

Epidemiology of systemic lupus erythematosus: a comparison of worldwide disease burden

Systemic lupus erythematosus (SLE) is a disease of multifactorial etiology. Quantifying the burden of SLE across different countries can clarify the role of genetic, environmental and other causative factors in the natural history of the disease, and to understand its clinical and societal consequences. The aim of this study is to summarize data on SLE incidence and prevalence in the USA, Europe, Asia, and Australia. An extensive review of electronic resources (PubMed and MedLine) and medical journals was conducted to identify published studies on SLE incidence and prevalence over the period of 1950-early 2006. Researchers in the countries of interest provided additional information on the epidemiology of SLE. The incidence and prevalence of SLE varies considerably across the countries. The burden of the disease is considerably elevated among non-white racial groups. There is a trend towards higher incidence and prevalence of SLE in Europe and Australia compared to the USA. In Europe, the highest prevalence was reported in Sweden, Iceland and Spain. There are marked disparities in SLE rates worldwide. This variability may reflect true differences across populations, or result from methodological differences of studies. The true geographic, racial, and temporal differences in SLE incidence and prevalence may yield important clues to the etiology of disease.

Epidemiology of systemic lupus erythematosus: a comparison of worldwide disease burden

Systemic lupus erythematosus (SLE) is a disease of multifactorial etiology. Quantifying the burden of SLE across different countries can clarify the role of genetic, environmental and other causative factors in the natural history of the disease, and to understand its clinical and societal consequences. The aim of this study is to summarize data on SLE incidence and prevalence in the USA, Europe, Asia, and Australia. An extensive review of electronic resources (PubMed and MedLine) and medical journals was conducted to identify published studies on SLE incidence and prevalence over the period of 1950-early 2006. Researchers in the countries of interest provided additional information on the epidemiology of SLE. The incidence and prevalence of SLE varies considerably across the countries. The burden of the disease is considerably elevated among non-white racial groups. There is a trend towards higher incidence and prevalence of SLE in Europe and Australia compared to the USA. In Europe, the highest prevalence was reported in Sweden, Iceland and Spain. There are marked disparities in SLE rates worldwide. This variability may reflect true differences across populations, or result from methodological differences of studies. The true geographic, racial, and temporal differences in SLE incidence and prevalence may yield important clues to the etiology of disease.

Epidemiology of systemic lupus erythematosus: a comparison of worldwide disease burden

Systemic lupus erythematosus (SLE) is a disease of multifactorial etiology. Quantifying the burden of SLE across different countries can clarify the role of genetic, environmental and other causative factors in the natural history of the disease, and to understand its clinical and societal consequences. The aim of this study is to summarize data on SLE incidence and prevalence in the USA, Europe, Asia, and Australia. An extensive review of electronic resources (PubMed and MedLine) and medical journals was conducted to identify published studies on SLE incidence and prevalence over the period of 1950-early 2006. Researchers in the countries of interest provided additional information on the epidemiology of SLE. The incidence and prevalence of SLE varies considerably across the countries. The burden of the disease is considerably elevated among non-white racial groups. There is a trend towards higher incidence and prevalence of SLE in Europe and Australia compared to the USA. In Europe, the highest prevalence was reported in Sweden, Iceland and Spain. There are marked disparities in SLE rates worldwide. This variability may reflect true differences across populations, or result from methodological differences of studies. The true geographic, racial, and temporal differences in SLE incidence and prevalence may yield important clues to the etiology of disease.

Epidemiology of systemic lupus erythematosus: a comparison of worldwide disease burden

Systemic lupus erythematosus (SLE) is a disease of multifactorial etiology. Quantifying the burden of SLE across different countries can clarify the role of genetic, environmental and other causative factors in the natural history of the disease, and to understand its clinical and societal consequences. The aim of this study is to summarize data on SLE incidence and prevalence in the USA, Europe, Asia, and Australia. An extensive review of electronic resources (PubMed and MedLine) and medical journals was conducted to identify published studies on SLE incidence and prevalence over the period of 1950-early 2006. Researchers in the countries of interest provided additional information on the epidemiology of SLE. The incidence and prevalence of SLE varies considerably across the countries. The burden of the disease is considerably elevated among non-white racial groups. There is a trend towards higher incidence and prevalence of SLE in Europe and Australia compared to the USA. In Europe, the highest prevalence was reported in Sweden, Iceland and Spain. There are marked disparities in SLE rates worldwide. This variability may reflect true differences across populations, or result from methodological differences of studies. The true geographic, racial, and temporal differences in SLE incidence and prevalence may yield important clues to the etiology of disease.

Epidemiology of systemic lupus erythematosus: a comparison of worldwide disease burden

Systemic lupus erythematosus (SLE) is a disease of multifactorial etiology. Quantifying the burden of SLE across different countries can clarify the role of genetic, environmental and other causative factors in the natural history of the disease, and to understand its clinical and societal consequences. The aim of this study is to summarize data on SLE incidence and prevalence in the USA, Europe, Asia, and Australia. An extensive review of electronic resources (PubMed and MedLine) and medical journals was conducted to identify published studies on SLE incidence and prevalence over the period of 1950-early 2006. Researchers in the countries of interest provided additional information on the epidemiology of SLE. The incidence and prevalence of SLE varies considerably across the countries. The burden of the disease is considerably elevated among non-white racial groups. There is a trend towards higher incidence and prevalence of SLE in Europe and Australia compared to the USA. In Europe, the highest prevalence was reported in Sweden, Iceland and Spain. There are marked disparities in SLE rates worldwide. This variability may reflect true differences across populations, or result from methodological differences of studies. The true geographic, racial, and temporal differences in SLE incidence and prevalence may yield important clues to the etiology of disease.

Prognostic factors in lupus nephritis

Systemic lupus erythematosus (SLE) is a heterogeneous disorder and its renal manifestations are protean. The course and prognosis of lupus nephritis is dependent on a large number of demographic, histopathological, serological, racial, socioeconomic and time dependent factors. Moreover, the initial and maintenance therapeutic regimens may also influence the long term renal outcome. This article reviews the important prognostic factors that have been reported in literature. The management strategy of lupus nephritis should be individualized and based on a composite of these parameters.

Outcome study of renal biopsy patients in Okinawa, Japan

Here we report a community-based epidemiologic study of patients who received renal biopsy in Okinawa, Japan between 1967 and 1994. The total number of cases was 2832 (1395 men and 1437 women), and the mean (SD) age at biopsy was 30.0 (10.0) years (range 1.0 to 88.0 years). The most common clinical indications for renal biopsy were proteinuria/hematuria (46.7%), nephrotic syndrome (21.2%), acute glomerulonephritis (10.1%), and systemic lupus erythematosus (7.5%). Patients who received renal biopsy between 1985 and 1994 (N= 1480) were much less likely to have acute glomerulonephritis than patients treated between 1967 and 1984 (N= 1352); the rates of proteinuria/hematuria, renal failure, and diabetes mellitus were slightly higher in the later period. Okinawa patients who began dialysis between 1971 and 2000 (N= 5246) were also studied. Among them, a total of 468 patients (260 men and 208 women) began dialysis after renal biopsy. The cumulative incidence of end-stage renal disease (ESRD) among these patients was 17% in 17 years. Half of these patients developed ESRD in the 5.8 years after renal biopsy. Among the dialysis patients, the biopsy rate was 12.6% in chronic glomerulonephritis, 1.7% in diabetes mellitus, 2.6% in nephrosclerosis, and 52.1% in systemic lupus erythematosus. The diagnoses of primary renal diseases were primarily made clinically. The survival rate after starting dialysis therapy was slightly better in those with than in those without renal biopsy but this finding was not statistically significant (adjusted hazards ratio 0.855, 95% CI 0.711-1.028, P= 0.095). The clinical significance of renal biopsy, other than its provision of histologic evidence, remains to be shown.

Proteinuria and the risk of developing end-stage renal disease

BACKGROUND

Dipstick urinalysis for proteinuria and hematuria has been used to screen renal disease, but evidence of the clinical impact of this test on development of end-stage renal disease (ESRD) is lacking.

METHODS

We assessed development of ESRD through 2000 in 106,177 screened patients (50,584 men and 55,593 women), 20 to 98 years old, in Okinawa, Japan, who participated in community-based mass screening between April 1983 and March 1984. We used data from the Okinawa Dialysis Study Registry to identify ESRD patients. Multivariate logistic analyses were performed to calculate adjusted odds ratio and 95% confidence interval (95% CI) for the significance of proteinuria and hematuria on the risk of developing ESRD with confounding variables such as age, gender, blood pressure, and body mass index. A similar analysis was repeated in a subgroup of screened patients in whom serum creatinine data existed.

RESULTS

During 17 years of follow-up, 420 screened persons (246 men and 174 women) entered the ESRD program. We identified a strong, graded relationship between ESRD and dipstick urinalysis positive for proteinuria; adjusted odds ratio (95% CI) was 2.71 (2.51 to 2.92, P < 0.001). Similar trends were observed after adding serum creatinine data. Compared with dipstick-negative proteinuria, adjusted odds ratio (95% CI) of proteinuria (1+) was 1.93 (1.53 to 2.41, P < 0.001) in men and 2.42 (1.91 to 3.06, P < 0.001) in women.

CONCLUSION

Proteinuria was a strong, independent predictor of ESRD in a mass screening setting. Even a slight increase in proteinuria was an independent risk factor for ESRD. Therefore, asymptomatic proteinuria warrants further work-up and intervention.