Treatment and clinical outcomes of elderly idiopathic membranous nephropathy: A multicenter cohort study in Korea

Idiopathic membranous nephropathy (MN) is the most common glomerulonephritis in elderly patients showing nephrotic syndrome. However, little is known about its treatment options and outcomes in elderly MN patients at long term follow-up. We retrospectively enrolled patients with biopsy-proven MN between April 1990 and December 2015 from eight tertiary hospitals in Korea. Among them, we excluded patients who had secondary causes of MN and subnephrotic-range proteinuria. We evaluated the presenting features and clinical outcomes and analyzed the all-cause mortality, renal outcomes, infection, and remission with respect to age. During the median follow-up at 77.2 months, 198 younger patients (<65 years) and 133 elderly patients (≥65 years) were enrolled. Age was an independent risk factor for all-cause mortality, renal outcome, and infection (for all P < 0.05) except remission. In elderly patients, there was no significant factor associated with mortality rate. The use of angiotensin-converting enzyme inhibitor (ACEI) or angiotensin II receptor blocker (ARB) was significantly associated with renal outcome and infection (renal outcome, hazard ration [HR] 0.06, 95% confidence intervals [CI] 0.01-0.36, P = 0.003; infection, HR 0.20, 95% CI 0.04-0.94, P = 0.041). Immunosuppressant therapy significantly increased renal outcome (P = 0.045) and infection (P = 0.029) compared with conservative therapy. In conclusion, old age is one of the clinically important predictors for MN patients. Among the treatment of elderly MN patients, only ACEI or ARB was associated with beneficial effects on renal outcome and infection. Elderly MN patients need a more tailored regimen considering their comorbidities and condition.