#873 Membranous nephropathy has higher all-cause mortality rate in comparison to focal segmental glomerulosclerosis and IgA nephropathy: a long-term study

Abstract

Abstract Background and Aims Membranous nephropathy, focal segmental glomerulosclerosis (FSGS) and IgA nephropathy are the most frequent types of primary glomerulonephrites in the adulthood. Glomerulonephritides may progress into end-stage renal disease despite appropriate treatment. Both the manifestations of the glomerulonephritides and medications for treatment might yield cardiovascular events such as venous thromboembolism, coronary artery disease and stroke. The purpose of this study is to compare three different types of primary glomerulonephritides in terms of all-cause mortality, kidney-related and cardiovascular outcomes. Method All patients who underwent kidney biopsy between 01.01.2000 and 01.06.2022 in Hacettepe University Hospital were screened and cases with primary glomerulonephritis and follow-up data were enrolled. Data regarding baseline demographics, laboratory and kidney pathology reports and outcomes were obtained. The primary end-point was defined as all-cause mortality. Kidney related and cardiovascular outcomes were determined as secondary end-points. Results population was 39 (18-81) years. Membranous nephropathy was present in 36.5% (n = 172), focal segmental glomerulosclerosis was present in 25.9% (n = 122) and IgA nephropathy was present in 37.6% (n = 177) of the cases. Age (p < 0.001), frequency of diabetes (p = 0.004) and smoking history (p = 0.020) were significantly higher in patients with membranous nephropathy than both FSGS and IgA nephropathy. Serum albumin levels were lower (p < 0.001), while total cholesterol (p < 0.001), LDL cholesterol (p < 0.001) and proteinuria levels (p < 0.001) were higher both in patients with membranous nephropathy than the other two groups and in patients with FSGS than IgA nephropathy. Median duration of follow-up was 120.2 (1.7-273.3) months (Table 1). All-cause mortality rate was significantly higher in patients with membranous nephropathy than the other two groups (p = 0.005); however the type of glomerulonephritides was not found to be related to all-cause mortality (HR: 1.07; 95% CI: 0.65-1.77; p = 0.770). Age (HR: 1.079; 95% CI: 1.05-1.10; p < 0.001), serum creatinine (HR: 1.35; 95% CI: 1.10-1.66; p = 0.003) and serum albumin (HR: 0.60; 95% CI: 0.38-0.95; p = 0.030) levels were found to be associated with all-cause mortality in patients with primary glomerulonephritides. The rates of ischemic stroke, atrial fibrillation and steroid induced diabetes were similar between all of the glomerulonephritides subgroups. Acute coronary syndrome (p = 0.015), coronary revascularization (p = 0.021) and venous thromboembolic events were more frequent in patients with membranous nephropathy than IgA nephropathy. There was no difference in terms of cardiovascular outcomes between the patients with FSGS and IgA nephropathy (Table 1). Although the remission rate was significantly higher in patients with membranous nephropathy than the other two groups (p < 0.001); there was not a distinct difference in relapse rates. Progression to end-stage renal disease was prominently lower in patients with membranous nephropathy than the other groups (p = 0.003) and loss of glomerular filtration rate per year was significantly higher in cases with FSGS compared to other groups (p = 0.021). Conclusion All-cause mortality risk was higher in patients with membranous nephropathy because of higher age at diagnosis and accompanying higher burden of comorbidities including diabetes and dyslipidemia. FSGS had a worse prognosis in terms of kidney related outcomes compared to other glomerulonephritides due to higher loss of glomerular filtration rate per year and increased rates of progression to end-stage renal disease. Intensive cardiovascular risk reduction strategies should be applied especially in patients with membranous nephropathy due to increased mortality rates.