Intensive versus conventional therapy to slow the progression of idiopathic glomerular diseases

Abstract

Background: Chronic kidney disease (CKD) caused by idiopathic glomerular diseases usually is progressive. Inhibition of the renin-angiotensin system (RAS) retards, but does not abrogate, CKD progression. Statins and spironolactone may decrease the rate of CKD progression independently or in addition to RAS inhibition.

Study design: Randomized open-label study.

Setting & participants: We recruited 128 patients (82 men and 46 women) with a clinical diagnosis of idiopathic chronic glomerulonephritis and estimated glomerular filtration rate (eGFR) >30 mL/min/1.73 m(2) (range, 36-102 mL/min/1.73 m(2)), and urine protein-creatinine ratio ranging from 1.1-5.2 g/g.

Intervention: Intensive therapy (a combination of RAS inhibitors [angiotensin-converting enzyme [ACE] inhibitors plus angiotensin receptor blockers [ARBs] plus a high-dose statin and spironolactone) versus conventional therapy (a regimen based on ACE inhibitors with a low-dose statin).

Outcomes: Changes in eGFR, proteinuria, and adverse events after 3 years of therapy.

Results: With intensive therapy, urine protein-creatinine ratio decreased from 2.65 (range, 1.1-5.2) to 0.45 (0.14-1.51) g/g (P < 0.001) and eGFR did not significantly change over time (64.6 +/- 2.1 vs 62.9 +/- 2.9 mL/min/1.73 m(2)). With conventional therapy, urine protein-creatinine ratio decreased from 2.60 (range, 1.32-5.4) to 1.23 (0.36-3.42) g/g (P < 0.001) and eGFR decreased from 62.5 +/- 1.7 to 55.8 +/- 1.9 mL/min/1.73 m(2) (P < 0.001). Comparison of the decreases in proteinuria and GFR between intensive versus conventional therapy was significantly different starting in the 1st and 12th months, respectively. Systolic blood pressure was lower with intensive than conventional therapy (113.5 +/- 1.4 vs 122.7 +/- 1.2 mm Hg; P < 0.01). We found an inverse relationship between percentage of decrease in proteinuria and change in eGFR (P < 0.001). Patients on intensive therapy were more likely to develop adverse events, such as hyperkalemia (9 vs 3 patients in the conventional therapy group) and discontinue therapy (15 vs 8 patients in the conventional therapy group).

Limitations: Open-label design.

Conclusions: A more intensive therapy that includes a combination of ACE inhibitors and ARBs plus high-dose statins and spironolactone may retard CKD progression more effectively than conventional therapy based on ACE inhibitors plus low-dose statin, but may lead to more adverse effects and discontinuation of therapy.