#2955 THE IMPACT OF SARS-COV-2 INFECTION ON LONG-TERM RENAL FUNCTION IN PATIENTS WITH GLOMERULAR DISEASES

Abstract Background and Aims We sought to evaluate the long-term effects of SARS-CoV-2 infection on renal function in patients with glomerular diseases. Method A total of 451 patients with biopsy-proven glomerular disease and at least 12 months of follow-up after COVID-19 pandemic onset were included in the study. A SARS-CoV-2 infection was diagnosed based on a positive RT-PCR and/or antigen test. Multivariate Cox proportional hazards regression analysis was performed to identify the independent predictors of a composite endpoint (≥30% decline in eGFR, ESRD). In addition, a multivariate linear regression analysis was developed to identify the impact of SARS-CoV-2 infection on eGFR decline at 12 months after pandemic onset. Results Since 26th February 2020, when the first case of SARS-CoV-2 infection was diagnosed in Romania, 23.1% of patients had a SARS-CoV-2 infection during a follow-up period of 2.5 y (0.8-2.6). The most frequent glomerular disease was IgA nephropathy (22.6%), followed by lupus nephritis (11.5%) and membranous nephropathy (9.5%). 71.8% of the study cohort received various regimens of immunosuppression. Patients with SARS-CoV-2 infection were younger and more likely to have received immunosuppressive therapy compared to patients without infection, but the renal function at baseline was similar between the study groups (eGFR, 52±31.2 vs 52.1±29.3 ml/min, respectively; p = 0.78). 17.6% of patients reached the composite endpoint, while 12.3% progressed to ESRD. Those with SARS-CoV-2 infection were more likely to reach the composite endpoint compared to those without infection [prevalence of composite endpoint, 26.7% vs. 14.8%, p = 0.006; OR, 2.1 (95%CI, 1.23-3.58), p = 0.006) (Figure 1). Similarly, there was a significant decline of eGFR in the first year of follow-up between the two study groups [-2.24 (-24.8; 20.9) vs. +2.31 (-16.8; 27.5) ml/min, respectively, p = 0.004]. In multivariate Cox proportional hazards regression analysis, the independent predictors of the composite endpoint were baseline eGFR (HR, 0.94; 95%CI, 0.92-0.95, p<0.001), the occurrence of SARS-CoV-2 infection (HR, 1.91; 1.16-3.12, p = 0.01) and male gender (HR, 1.64; 95%CI, 1.01-2.66, p = 0.04). When taking into account the severity of SARS-CoV-2 infection, a severe infection was the most important predictor of the composite endpoint (HR, 2.1; 95%CI, 1.02-4.29, p = 0.04) (Figure 2). The results remained consistent when restricting the analysis to ESRD as an endpoint. When taking into account the eGFR slope at 12 months after COVID-19 pandemic onset as the outcome variable in multivariate linear regression analysis, the SARS-CoV-2 infection occurrence independently determined a reduction of eGFR by 4.62 ml/min/1.73m2 (β coefficient, -4.62; 95%CI, -7.74 to -1.5, p = 0.004). Conclusion There is a significant impact of SARS-CoV-2 infection on long-term renal function in patients with glomerular diseases, while those with severe infection had a greater decline of eGFR and a worse renal survival.