(50) Characterization and Treatment Patterns of Systemic Lupus Erythematosus Patients - Data from a Large Israeli Health Maintenance Organization

Publication Number: 381

Background: Systemic lupus erythematosus (SLE) is a chronic systemic autoimmune disorder that can inflict organ damage. There is limited evidence on the real-world distribution of clinical manifestations and the long-term treatment among SLE patients.

Objectives: To characterize SLE patients and to examine their current and past treatment patterns.

Methods: A retrospective study using the computerized database of Maccabi Healthcare Services (MHS), a large health maintenance organization. Prevalent SLE patients on Dec 31 2020 were defined according to: first diagnosed with SLE at the age ≥10 years; ≥1 purchase of hydroxychloroquine (HCQ); ≥1 positive anti-nuclear antibodies (ANA) lab test. Patients diagnosed with dermatomyositis and/or systemic sclerosis were excluded. Descriptive statistics was used to characterized patients by SLE-related manifestations and by current and past treatment with HCQ, immunosuppressants (ISs) and prednisone. Multivariate logistic-regression model was used to identify factors associated with non-treatment.

Results: We identified 1073 SLE patients (prevalence rate of 55.6 per 100,000 among MHS members), with a mean age of 50.7 (±14.9) and of whom 87.8% were females. The age at first diagnosis was 37.2 (± 14.4) and SLE duration was 12.9 (±6.2) years. The distribution of SLE related manifestations was: cutaneous (74.4%); hematologic (72.9%); renal (46.3%); musco-skeletal (22.8%); neurologic (8.1%) and serositis (7.4%). Initiation of HCQ within 12 months of diagnosis gradually increased from 51.0% in 2000 to >90% in those diagnosed as of 2013. Examination of the treatment patterns during 2010-2020 revealed that the annual proportion of untreated patients ranged between 20-26%. The proportion of untreated patients increased with disease duration and during 2020 the distribution was: 11% in those with < 5 years; 22% in those with 6-10; 28% among those with ≥11. A multivariate logistic regression model revealed that compared to patients with a disease duration of < 5 years, patients with a disease duration of 6-10 years and ≥11 years had increased odds for non-treatment (odds ratio [OR] 3.05, 95% confidence interval [CI] 1.45-6.39; OR 5.12, 95% CI 2.55-10.34, respectively). Decreased odds (P < 0.05) for non-treatment were observed among those with SLE manifestations, those previously treated with ISs and/or prednisone and those with ≥1 visit to a rheumatologist in 2020.

Conclusions: Despite the increase in the initiation of HCQ treatment close to the SLE diagnosis, approximately 25% of all patients are untreated. Although some of these patients might have a mild form of SLE, efforts should be made to identify these patients, refer them to rheumatologists in order for them to receive appropriate treatment and reduce the chance of future damage.