Primary IgA nephropathy in elderly patients.

Abstract

Data on clinicopathological features, treatment and outcomes of IgA nephropathy (IgAN) in elderly patients are limited. Native kidney biopsies with a pathological diagnosis of IgAN (n = 1084) from Mayo Clinic Rochester in the years 1994-2013 were examined. After exclusion of the secondary IgAN, 45 elderly IgAN patients (age ≥65 years) were identified. One hundred sixty-two younger adults (age 18-64 years) with IgAN were randomly selected for comparison. Compared with younger adults, elderly patients showed a higher rate of chronic hypertension (62.2 vs 27.2%), higher pulse pressures (65 ± 17 vs 51 ± 15 mmHg), requiring greater number of antihypertensive medications (2.5 ± 1.2 vs 1.7 ± 0.7) and lower blood haemoglobin (11.1 ± 2.3 vs 12.7 ± 2.1 g/dL) at time of kidney biopsy, all P < 0.001. Pathologically, elderly kidneys showed a higher degree of tubulointerstitial fibrosis (P = 0.04) and vascular sclerosis (P < 0.001). Treatments (including the use of angiotensin-converting enzyme inhibitor (ACEI) inhibitor, angiotensin II receptor blocker (ARB) and immunosuppressants) were similar in the two cohorts. Elderly patients had more end-stage renal disease at 6 months (HR 5.51; 95% CI 1.46-22.3, P = 0.01) and higher 6-month and 5-year mortality (HR 2.31; 95% CI 1.04-5.17, P = 0.04) after adjusting the age and comorbidities. IgAN diagnosed at age >65 years tends to have a faster renal disease progression and higher patient mortality.