Comparing Long-Term Outcomes in Glomerular Disease Patients Presenting with Nephrotic Syndrome Versus Nephrotic Range Proteinuria.

BACKGROUND

Despite extensive research on proteinuria's impact on chronic kidney disease progression, there is no direct comparison of outcomes in biopsy-diagnosed glomerular disease (GD) patients with nephrotic syndrome (NS) or nephrotic range proteinuria (NRP). Our study addresses this gap, comparing long-term outcomes between NS and NRP.

METHODS

We conducted a retrospective study on 240 kidney biopsy-proven GD patients, tracked from 2010 to 2015 until end-stage kidney disease (ESKD), death, or the study end in January 2022.

RESULTS

The median follow-up was 8.8 years. Diagnoses were predominantly nonproliferative (53%), proliferative (25%) nephropathies, diabetic nephropathy (12%), and paraprotein diseases (10%). NS was observed in 141 (59%) patients, presenting more frequently with arterial hypertension, higher eGFR, increased proteinuria, and dyslipidemia than NRP patients. NRP patients often had proliferative GD and diabetic nephropathy; their renal chronicity score was higher. The ESKD endpoint occurred in 35% NS and 39% NRP patients ( 0.4). The cohort's mean kidney survival time was 8.2 years. In a multivariate analysis, NS, lower eGFR, a higher renal chronicity score, and diabetic nephropathy were associated with ESKD. A total of 64 patients (27%) died, 73% post-kidney replacement therapy initiation, and mostly from cardiovascular disease (63%). Mortality between proteinuria forms showed no difference. The multivariate analysis found lower eGFR, a higher Charlson comorbidity score, and diabetic nephropathy associated with mortality.

CONCLUSIONS

Our study found no difference in all-cause mortality between NS and NRP in glomerular diseases. However, an adjusted analysis revealed poorer kidney survival for NS patients, emphasizing the need for personalized management to improve renal prognoses.