Cost-of-illness changes before and after the diagnosis of systemic lupus erythematosus: a nationwide, population-based observational study in Korea.

OBJECTIVES: To estimate the direct healthcare cost progression from before to after systemic lupus erythematosus (SLE) diagnosis and to compare healthcare costs by disease severity. METHODS: Patients with incident SLE diagnosed between 2008 and 2018 were identified from the Korean National Health Insurance database. Annual direct healthcare costs for 5 years before and after SLE were estimated and compared with those of age-, sex-, and calendar month-matched (1:4) controls, without SLE. Direct healthcare costs were compared by disease severity of SLE using regression analysis. RESULTS: Among 11 173 patients with SLE and 45 500 subjects without SLE, annual direct healthcare costs per person increased in the year before SLE diagnosis and peaked in the first year after diagnosis. They were 7.7-fold greater in the SLE patients than in the subjects without SLE ($5,871 vs $759). Severe SLE was associated with 3.284-fold (95% CI 3.075-3.507) higher annual costs than mild SLE during the year after diagnosis. Older age (age 60-79 years), lupus nephritis, interstitial lung diseases, and comorbidities such as avascular necrosis and chronic kidney disease were associated with higher annual direct healthcare costs (times [95% CI]) in the first year after diagnosis; aged 60-69, 1.119 [1.034-1.211], aged 70-79, 1.470 [1.342-1.611], 1.794 [1.711-1.881], 1.435 [1.258-1.638], 6.208 [4.541-8.487], and 1.858 [1.673-2.064], respectively. CONCLUSION: Patients with SLE incurred significantly high direct healthcare costs than subjects without SLE during the first year after diagnosis. Disease severity, older age, major organ involvements and comorbidities were associated with increased healthcare costs.

Korean LupusPRO: Cross-Cultural validation study for systemic lupus erythematosus.

OBJECTIVE: To establish the reliability and validity of the Korean version of LupusPRO version 1.7 (v1.7) for systemic lupus erythematosus (SLE) patients. METHODS: LupusPRO v1.7 was translated into Korean, followed by pretesting among five native Korean speakers. We administered the LupusPRO v1.7 survey to five SLE patients and made minor changes to clarify the language. Then, 133 SLE patients participated in the validation procedure. In each domain, the internal consistency reliability (ICR) and test-retest reliability (TRR) were assessed using Cronbach's alpha and the intra-class correlation coefficient (ICC), respectively. Criterion validity was evaluated using Spearman's correlation coefficient with the other measures such as SF-36, EQ-5D VAS, and SELENA-SLEDAI PGA. Construct validity was assessed by confirmatory factor analysis (CFA) using the unweighted least square estimation method. RESULTS: The mean age of the 133 patients was 36.14 years, and 97% of them were women. Analysis of 130 returned questionnaires revealed that most ICRs of the Korean LupusPRO v1.7 domains were acceptable, with Cronbach's alphas in the range of 0.579-0.949, and most TRRs were good with ICCs from 0.582 to 0.851. Criterion validities presented significant correlations between the LupusPRO v1.7 and other measures validated. In the analysis of the CFA model, the goodness of fit indices demonstrated an acceptable fit. Factor loadings for most individual items were between 0.548 and 0.985. The average variance extracted (AVE) and composite reliability (CR) of most domains were greater than 0.5 and 0.7, respectively, demonstrating acceptable convergent and discriminant validities. CONCLUSIONS: The Korean version of LupusPRO v.17 had acceptable reliability and validity.

The Prevalence of Sjögren's Syndrome in Rheumatoid Arthritis Patients and Their Clinical Features.

BACKGROUND: To estimate the prevalence of Sjögren's syndrome (SS) in patients with rheumatoid arthritis (RA) and to compare the clinical features of RA patients with and without SS. METHODS: We conducted a retrospective study of RA patients who visited a rheumatology clinic in a tertiary referral hospital in Korea between May 20 and July 22, 2016. All patients fulfilled the classification criteria for RA, and the diagnosis of SS was made clinically by rheumatologists and according to the 2002 American-European Consensus Group (AECG), 2012 American College of Rheumatology (ACR), and 2016 ACR/European League Against Rheumatism (EULAR) classification criteria. The prevalence was estimated as the number of SS patients within the total number of RA patients. The disease activity and treatment pattern of RA were compared between patients with and without SS. RESULTS: Among 827 RA patients, 72 patients (8.7%) were diagnosed with SS by a rheumatologist, though only 60 patients (7.3%) satisfied the 2002 AECG classification criteria for SS. Fifty-two patients (6.3%) and 56 patients (6.8%) fulfilled the 2012 ACR and 2016 ACR/EULAR classification criteria, respectively. The prevalence of SS in RA patients was 10.5%, 17.0%, and 67.6% in rheumatoid factor, antinuclear antibody (≥ 1:80), and anti-Ro antibody positive patients, respectively. CONCLUSION: The prevalence of SS among RA patients was 8.7% according to rheumatologists' diagnosis. The presence of SS did not affect the treatment patterns of RA patients. However, the autoantibody profiles and demographics of RA patients with SS differed from those of patients without SS.

Effectiveness of Korean Red Ginseng on fatigue in patients with rheumatic diseases: a randomized, double-blind, placebo-controlled study.

BACKGROUND: To evaluate the effectiveness of Korean Red Ginseng (KRG) in managing fatigue in Korean patients with rheumatic diseases. METHODS: Patients were randomly assigned to KRG (2 g/day, n = 60) or placebo (n = 60) groups for 12 weeks of blind phase and then open-label KRG from weeks 12 to 24 (placebo-KRG, continuous-KRG). The primary outcome was the improvement rate in fatigue, defined by an increase in Functional Assessment of Chronic Illness Therapy (FACIT)-Fatigue scores at 12 weeks. Secondary outcomes included changes in FACIT-Fatigue and fatigue visual analog scale (VAS) between 0 and 12 weeks and those changes in both indices at 24 weeks. RESULTS: The study enrolled 120 patients (Sjogren syndrome [n = 53], rheumatoid arthritis [n = 43], or both diseases [n = 24]). The mean age was 50.9 ± 11.6 years, with 97.5% being female. Baseline characteristics were similar between the two groups. The improvement rate in FACIT-Fatigue after 12 weeks was higher in the KRG group than in the placebo group, but the difference was statistically insignificant (38.3% vs. 26.7%, p = 0.242). Improvement in fatigue was observed in both groups by increases in FACIT-F (4.6 vs. 4.0) and reductions in fatigue VAS (-16.0 vs. -12.2) scores at 12 weeks. The most frequently reported adverse events during KRG use were pruritus and urticarial, with no significant difference between the two groups. CONCLUSION: Both KRG and placebo groups showed significant reductions in fatigue. KRG treatment for 24 weeks did not reduce fatigue symptoms more than the placebo in patients with rheumatic diseases.

Increased cardiovascular risk in Korean patients with systemic lupus erythematosus: a population-based cohort study.

To determine the increased risk of major adverse cardiovascular events (MACE) in patients with systemic lupus erythematosus (SLE) compared to the general population in Korea. Using data from the National Health Insurance Service database spanning 2008 to 2018, incident SLE patients aged 18 years and above were selected along with a 1:4 age- and sex-matched control group. The crude incidence rate (IR) of MACE was calculated as the number of events per 1000 person-years and the IR ratio (IRR) for MACE was adjusted using generalized estimating equations. Subgroup analysis was conducted to evaluate the risk differences of overall MACE and its composites based on age and sex stratification. The study included 8568 SLE patients and 34,272 controls. The cumulative IR of MACE per 1000 person-years in SLE patients and controls were 4.08 and 1.30, respectively. After adjusting for confounders, SLE patients had a higher risk of MACE compared to the general population (adjusted IRR of 2.40 [95% confidence interval [CI] 1.88-3.05]), with no gender differences observed. The increased risk of MACE in SLE patients was highest in the 18-39 age group (IRR 11.70, 95% CI 5.95-23.01) and gradually decreased with age. The increased risk of ischemic stroke (IRR 2.41, 95% CI 1.84-3.15) and myocardial infarction (IRR 2.19, 95% CI 1.30-3.68) in SLE patients was comparable. The risk of MACE in SLE patients is 2.40 times higher than that of the general population, with a higher relative risk observed in younger individuals.

Epidemiology of systemic lupus erythematosus in Korea.

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease characterized by diverse organ system disabilities, predominantly affecting young females. The clinical manifestations of SLE encompass various organs, including the kidney, cardiovascular system, and central nervous system. Young females with SLE experience higher mortality rates than the general population, making it imperative to gain insights into the disease patterns and associated factors. The current review examines the epidemiological studies to analyze the prevalence, incidence, and mortality trends of SLE in Korea and compares them with the findings from other countries. We aim to identify potential similarities, differences, and factors contributing to the burden of SLE in different populations by exploring the comparative epidemiological aspects. The knowledge derived from this comparison would aid in advancing the overall management of SLE in Korea.

Risk of end-stage renal disease in patients with early-onset lupus nephritis: A population-based cohort study.

OBJECTIVE: To compare the risk of end-stage renal disease (ESRD) between patients with early-onset lupus nephritis (EOLN) and those with delayed-onset LN (DOLN). METHODS: This retrospective study of incident cases of systemic lupus erythematosus (SLE) used nationwide Korean claims databases and data from 2008 through 2018. We divided LN patients into two groups: the EOLN group (with LN onset within 12 months of SLE diagnoses) and the DOLN group (with LN onset later than 12 months after SLE diagnoses). Patients were observed from the date of LN diagnosis to the development of ESRD, death, or the last follow-up. Cox proportional hazards modeling was used to predict hazard ratios (HRs) for progression to ESRD with death as a competing risk. RESULTS: We identified 3779 incident SLE patients who developed LN during follow-up: 60 % (n = 2281) had EOLN, and 40 % (n = 1489) had DOLN. Sixty-nine patients with EOLN (3.0 %) and 29 patients with DOLN (1.9 %) progressed to ESRD. After adjusting for confounders, the ESRD risk associated with EOLN was comparable to the risk associated with DOLN (HR 1.10, 95 % confidence interval [CI] 0.57 to 2.11). In the subgroup of patients on aggressive immunosuppressive therapy (670 with EOLN and 179 with DOLN), the ESRD risk was higher in the DOLN group (HR 2.6, 95 % CI 1.11 to 6.10). CONCLUSION: The risk of ESRD was comparable between patients with EOLN and DOLN. However, among patients on aggressive immunosuppressive therapy, compared with EOLN, DOLN was associated with a higher risk of progression to ESRD.

Increased risk of malignancy in patients with systemic lupus erythematosus: population-based cohort study in Korea.

BACKGROUND: This study aimed to evaluate the crude incidence rates and relative risk of malignancy in Korean patients with SLE. METHODS: We conducted a retrospective nationwide cohort study using databases from the National Health Insurance Service in Korea. All prevalent SLE patients aged over 19 were identified from January 2012 to December 2014 and observed until the diagnosis of malignancy, death, or end of the study, December 2015. The crude incidence rates (IRs) and standardised incidence ratios (SIRs) of overall and site-specific malignancies in SLE patients were estimated. RESULTS: We identified 17,854 SLE patients and during the observation period (60,511 person-years [PYs]), 768 solid malignancies (126.9/10,000 PYs) and 68 haematologic malignancies (11.2/10,000 PYs) occurred in SLE patients. In SLE patients, breast and reproductive system and thyroid cancers occurred predominantly, followed by liver and colon cancers. The SIRs of overall, solid, and haematologic malignancies of SLE patients compared to the general population were 1.8 (95% confidence interval [CI] 1.6-1.9), 1.7 (95% CI 1.5-1.8), and 5.9 (95% CI 4.8-7.3), respectively. In solid malignancies, head and neck (2.7, 95% CI 1.1-4.2), bladder (2.4, 95% CI 1.1-3.8), liver (1.9, 95% CI 1.4-2.3), pancreas (1.9, 95% CI 1.3-2.6), lung (1.8, 95% CI 1.2-2.4), colon (1.7, 95% CI 1.3-2.2), thyroid (1.6, 95% CI 1.3-1.8) and breast and reproductive system (1.5, 95% CI 1.2-1.7) cancers are at increased risk in SLE patients. CONCLUSION: An increased risk of haematologic and solid malignancies was observed in Korean patients with SLE compared to the general population.