From the Guidelines
The treatment of proteinuria should prioritize the use of angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin II receptor blockers (ARBs) as first-line therapy, with uptitration to maximally tolerated or allowed daily dose, as recommended by the most recent guideline evidence 1. The goal of treatment is to address the underlying cause of proteinuria while protecting kidney function and reducing the risk of progression to end-stage renal disease.
- Key considerations in the management of proteinuria include:
- Blood pressure control, with a target of <130/80 mmHg for most patients with proteinuria
- Lifestyle modifications, such as sodium restriction (<2g daily), moderate protein intake (0.8g/kg/day), regular exercise, weight management, and smoking cessation
- Tight glycemic control for diabetic patients with proteinuria, aiming for HbA1c <7%
- Use of diuretics, such as furosemide (20-80 mg daily), to manage edema in cases of nephrotic-range proteinuria (>3.5g/day)
- Consideration of immunosuppressive therapy for immune-mediated causes of proteinuria
- The use of ACEIs or ARBs has been shown to reduce protein excretion by decreasing intraglomerular pressure and slow the progression of kidney disease, as supported by the guideline evidence 1.
- Regular monitoring of kidney function, proteinuria levels, and medication side effects is necessary to adjust treatment and ensure optimal outcomes, as recommended by the guideline evidence 1.
From the FDA Drug Label
The RENAAL study was a randomized, placebo-controlled, double-blind, multicenter study conducted worldwide in 1513 patients with type 2 diabetes with nephropathy (defined as serum creatinine 1.3 to 3.0 mg/dL in females or males ≤60 kg and 1.5 to 3. 0 mg/dL in males >60 kg and proteinuria [urinary albumin to creatinine ratio ≥300 mg/g]). Compared with placebo, losartan significantly reduced proteinuria by an average of 34%, an effect that was evident within 3 months of starting therapy
- Treatment of proteinuria: Losartan reduces proteinuria by an average of 34%.
- Key findings: The effect of losartan on proteinuria was evident within 3 months of starting therapy.
- Study reference: 2
From the Research
Treatment of Proteinuria
- Proteinuria is identified as an important marker and risk factor of progression in chronic kidney disease 3
- Reversing intraglomerular hypertension with protein restriction or antihypertensive therapy may be beneficial both by diminishing hemodynamic injury to the glomeruli and by reducing protein filtration 3
Role of Angiotensin-Converting Enzyme (ACE) Inhibitors and Angiotensin Receptor Blockers (ARBs)
- Blockade of the renin-angiotensin system with either an ACE inhibitor or an ARB was shown to decrease urinary protein excretion and slow the progression of both diabetic and nondiabetic proteinuric renal disease 4
- Combination therapy with an ACE inhibitor and an ARB resulted in a further decrease in proteinuria compared with an ACE inhibitor alone 4
- ARBs that specifically block the AT(1) receptor offer the potential to prevent or delay progression to end-stage renal disease independently of reductions in blood pressure 5
Comparison of ACEIs and ARBs
- ACEIs and ARBs showed no significant differences in reducing proteinuria or albuminuria in primary hypertension 6
- The efficacies of ACEIs and ARBs in controlling blood pressure as a secondary indicator were also similar 6
Therapeutic Use of RAAS Inhibition
- ACE inhibitor or ARB therapy in hypertensive diabetic patients with macroalbuminuria, microalbuminuria, or normoalbuminuria has been repeatedly shown to improve cardiovascular mortality and reduce the decline in glomerular filtration rate 7
- Dual RAAS inhibition with ACE inhibitors plus ARBs or ACE inhibitors plus direct renin inhibitors has failed to improve cardiovascular or renal outcomes but has predisposed patients to serious adverse events 7