Analysis of clinical, immunological characteristics, damage, and survival in 300 Turkish systemic lupus erythematosus patients.

OBJECTIVE: This retrospective study aimed to conduct a comprehensive analysis of Turkish Systemic Lupus Erythematosus (SLE) patients of Caucasian ethnicity, focusing on their clinical, immunological, and therapeutic characteristics, damage accural and mortality.

PATIENTS AND METHODS: We carried out a retrospective assessment of 300 SLE patients diagnosed between 2001 and 2017 at Kocaeli University Rheumatology Clinic. Demographic data, clinical manifestations, immunological profiles, treatment approaches, disease-related damage, and survival information were collected.

RESULTS: The study population had a significant female predominance (89%) with a mean age of disease onset of 35.4 (SD:13.3) years. Hematological (72.6%) and mucocutaneous (72%) manifestations were the most common clinical findings, followed by arthritis (66.3%). Females had higher frequency of photosensitivity (p = 0.019), malar rash (p < 0.001), and alopecia (p = 0.014). Anti-dsDNA antibodies were detected in 61.6% of patients, while 57% of patients had hypocomplementemia. Secondary antiphospholipid syndrome was observed in 15.3% of patients; the most common manifestations included deep venous thrombosis (32.6%) and cerebrovascular accidents (30.4%). Lupus Nephritis (LN) affected 40.3% of the cohort. The most common pathologic finding was Class IV LN (30.5%). Eventually, 13 (4.3%) patients developed chronic kidney disease (CKD) and 4 had renal replacement therapies. Patients with LN had higher usage of pulse steroids, azathioprin, mycophenolate mofetil, cyclophosphamide, and rituximab (p < 0.001 for each).  In the juvenile-onset group (n = 31, 10.3%), an increased occurrence of malar rash (p = 0.009), nephritis (p = 0.034), hypocomplementemia (p = 0.001), positive anti-dsDNA (p = 0.007), anti-Sm (p = 0.046), anti-rib-P (p = 0.014) antibodies were observed. At least one damage parameter was observed in 32.6% patients with musculoskeletal manifestations being the most common. Thirteen patients were diagnosed with various malignancies, with cervical cancer being the most common (4 cases). The total 5 and 10-year survival rates were 92.5% and 86.7%, respectively. However, patients with CKD, had lower survival rates; 75% at 3 years and 60% at 15 years. Regression analysis demonstrated an association of CKD and  history of infections with decreased survival (p = 0.02, each).

CONCLUSION: Ethnicity and geography influence the clinical diversity of SLE. Recognizing these disparities is crucial for tailoring patient care. Future inception cohort studies in Turkish SLE patients are necessary to address the limitations of retrospective research.