Aims: To investigate demographic, clinical, laboratory, and immunological characteristics of patients with systemic lupus erythematosus (SLE) in southeastern areas of South Korea, and to perform survival analysis. Methods: We retrospectively evaluated 413 patients with SLE diagnosed in 3 tertiary rheumatology centers in South Korea from 1992 to 2016 by reviewing their medical charts. All patients fulfilled the 1997 revised American College of Rheumatology classification criteria for SLE.Results: Most patients were women (92%), and the mean (±standard deviation) age at diagnosis was 30.9 (±12.9) years. The most common clinical manifestation was leukopenia (74.3%), followed by lymphopenia (73.6%), arthritis (59.1%), malar rash (48.4%), thrombocytopenia (46.5%), oral ulcer (35.1%), and biopsy-proven lupus nephritis (31.2%). Anti-nuclear, anti-double-stranded DNA, anti-Smith, and anti-Ro antibodies were positive in 97.8%, 70.1%, 38.4%, and 63% of patients, respectively. Twenty (4.8%) patients died during a median follow-up of 83 months, and the cumulative 5-year and 10-year survival rates were 96.9% and 95.5%, respectively. The major causes of death were infection (50%) and lupus flare-up (50%). Male (hazards ratio[HR] = 7.19, P = .001), pleuritis and/or pericarditis (HR = 3.28, P = .012), childhoodonset (HR = 3.57, P = .012), and late-onset (HR = 4.65, P = .011) were independent risk factors for death. Compared with SLE cohorts in other ethnicities or countries, our patients tended to have a higher frequency of anti-Ro antibodies and hematologic disorders.
Conclusion: This study describes clinical features of SLE in South Korea and suggests a remarkable phenotypic heterogeneity of SLE. K E Y W O R D S epidemiology, ethnic groups, mortality, Republic Korea, systemic lupus erythematosus | 93 KOH et al.Age at diagnosis, y, mean ± SD 30.9 ± 12.8
Age at diagnosisChildhood-onset, ≤18 y, n (%) 57 (13.8)Adult-onset, >18 to 50 y, n (%)
(77.2)Late-onset, >50 y, n (%) 37 (9) Onset age of first symptoms, y, mean ± SD 29.9 ± 12.6Observation period, mo, median (IQR) 83 (36-139) Cumulative clinical manifestations Mucocutaneous lesions, n (%) 337 (81.6) Malar rash, n (%) 200 (48.4) Discoid rash, n (%) 66 (16.0) Photosensitivity, n (%) 96 (24.0) Oral ulcer, n (%) 145 (35.1) Arthritis, n (%) 244 (59.1) Pericarditis, n (%) 68 (16.5) Pleuritis, n (%) 89 (21.5) LN, n (%) 129 (31.2) Class II, a n (%) 12 (2.9) Class III, b n (%) 28 (6.8) Class IV, c n (%) 70 (16.9) Class V, d n (%) 19 (4.6) Neuropsychiatric disorders, n (%) 51 (12.4) Psychosis, n (%) 25 (6.1) Seizure, n (%) 5 (9.8) Hematologic disorders, n (%) 335 (81.1) Hemolytic anemia, n (%) 36 (8.7) Leukopenia, n (%) 307 (74.3) Lymphopenia, n (%) 304 (73.6) Thrombocytopenia, n (%) 192 (46.5) Chronic interstitial lung disease, n (%) 7 (1.7) Pulmonary hypertension, n (%) 12 (2.9) Secondary APS, n (%) 23 (5.6) Secondary Sjögren's syndrome, n (%) 25 (6.1) Prevalence of antibodies eANA ≥ 1:40, n (%) 404 (97.8) Anti-dsDNA, n (%) 246/351 (70.1) Anti-Sm, n (%) 129/336 (38.4) Anti-cardiolipin ...
