#2051 Long-term follow-up of Israeli patients with lupus nephritis
Authors: Hagai Keren Cohen , Benchetrit Sydney , Kabaha Mohamad , Bar-Ziv Dorin , Pri-Paz-Basson Yael , Kivity Shaye , Tayer-Shifman Oshrat E 
Published: May 2024

Abstract

Background and Aims
Systemic lupus erythematosus (SLE) often affects the kidneys, and is associated with morbidity and mortality. Ethnic variations in clinical response to treatment and outcomes have been described. Information on real-life, long-term cohorts of the Middle Eastern Israeli population is lacking.
We aimed to characterize the prevalence and long-term outcomes of kidney involvement in SLE patients in Israel and to identify variables associated with lupus nephritis (LN) and end-stage kidney disease (ESKD).

Method
This retrospective study, conducted between 2014-2023, included adult patients with SLE diagnosed for at least 12 months. Kidney involvement was based on a diagnosis of LN on a kidney biopsy. SLE patients without LN served as controls. Associated variables were collected including socio-demographics, disease-related characteristics, kidney-related factors, comorbidities, and all-cause mortality.

Results
A total of 182 adult patients with SLE were included. Of them, 54 (29.6%) had LN. Mean follow-up since diagnosis was 16.2 ± 13.8 years. Compared to the control group, patients with LN were diagnosed with SLE at younger ages (26.8 ± 12.9 vs. 35.5 ± 15.4 years, p &lt; 0.01). Patients with LN and controls had similar proportions of females/males and Jewish/Arab patients (Table 1), and had comparable baseline eGFR before LN diagnosis (110 ± 48 vs. 107 ± 39 ml/min/m2, p = 0.66). The LN group had lower complement C3 levels at diagnosis and higher dsDNA titers (p = 0.001, 0.023 respectively; Table 1). Patients with LN had more hospitalization for SLE exacerbations [38.4% vs. 24.5%, odds ratio (OR) 1.9, 95% confidence interval (CI) 1-3.9, p = 0.06].
Of 54 patients with LN, 45 had available treatment information. All patients were treated with hydroxychloroquine, 19 patients (42.2%) were treated with cyclophosphamide, and 36 (80%) were treated with mycophenolate mofetil or mycophenolic acid. During follow-up of the LN patients, 5 patients (9.3%) were diagnosed with diabetes, 21 patients (38.9%) were diagnosed with hypertension, 5 patients (9.3%) had a stroke and 6 patients (11.1%) had an acute coronary syndrome.
Eight of the LN patients (14.8%) developed ESKD as compared with one patient (0.8%) of the controls (OR 22.1, 95% CI 2.7-181.5, p &lt; 0.001). On univariate analysis, ESKD was significantly associated with LN, hypertension, heart failure, and non-employment status. No difference in the rate of ESKD was found between Jewish and Arab patients. On multivariate regression analysis, LN and hypertension were the most important predictors for developing ESKD. Mortality among patients with ESKD was 22% vs. 4.6% among non-ESKD patients (p = 0.02) )Fig. 1).

Conclusion
This long-term study on Israeli SLE patients reveals that despite advances in SLE treatments, LN is associated with significant morbidity and mortality. The elevated risk of ESKD, particularly associated with LN and hypertension, underscores the imperative for targeted interventions to improve outcomes.