How to Improve Kidney Function in Chronic Kidney Disease
The most effective approach to improving kidney function in CKD combines SGLT2 inhibitors as first-line therapy with blood pressure control targeting <120 mmHg systolic, RAS inhibitors (if albuminuria present), lifestyle modifications including regular exercise and dietary changes, and treatment of underlying causes. 1, 2
Pharmacological Interventions (Priority Order)
First-Line Disease-Modifying Medications
SGLT2 Inhibitors are now the cornerstone of nephroprotection, even in non-diabetic patients. These agents reduce hyperfiltration, proteinuria, inflammation, and fibrosis across multiple renal compartments. 3, 4 They should be continued until dialysis or transplantation. 2
RAS Inhibitors (ACE-I or ARB) at maximum tolerated dose remain crucial when pathological albuminuria is present (albumin-to-creatinine ratio >30 mg/g). 1, 3 In type 1 diabetes with any degree of albuminuria, ACE inhibitors delay nephropathy progression. In type 2 diabetes with microalbuminuria, both ACE inhibitors and ARBs delay progression to macroalbuminuria. 5 If one class is not tolerated, substitute the other.
Nonsteroidal Mineralocorticoid Receptor Antagonists (like finerenone) are recommended for diabetic patients to enhance nephroprotection. 2, 3 Steroidal MRAs can be added for resistant hypertension. 2
GLP-1 Receptor Agonists provide additional kidney protection, particularly in diabetic nephropathy. 2, 3
Blood Pressure Management
Target systolic BP <120 mmHg when possible, which shows superior outcomes compared to less aggressive targets. 1, 2 For patients with albuminuria ≥30 mg/24 hours, target <130/80 mmHg. 6 Add dihydropyridine calcium channel blockers and/or diuretics as needed to achieve targets. 2 The ABCD trial demonstrated that achieving mean BP of 128/75 mmHg reduced strokes and delayed nephropathy progression compared to 137/81 mmHg. 7
Lipid Management
Use statin-based therapy (moderate- or high-intensity) and continue until dialysis or transplant. Add ezetimibe or PCSK9 inhibitors based on ASCVD risk and lipid levels. 2
Lifestyle Modifications
Physical Exercise
Exercise significantly improves both renal and cardiovascular function. 8, 9
- Resistance exercise (RE) or RE with blood flow restriction provides the greatest improvements in eGFR and blood pressure according to network meta-analysis. 8
- Aerobic exercise significantly improves serum creatinine, blood pressure, and VO2peak. 8
- Target: 150 minutes per week of regular physical activity. 3
- Exercise reduces all-cause mortality, particularly in dialysis-dependent patients, and helps preserve residual renal function. 9
Dietary Interventions
Adopt a Mediterranean or plant-based diet high in fruits, vegetables, whole grains, and nuts. 1, 3
Sodium restriction to <5 g salt per day (<2,300 mg sodium) lowers blood pressure in both normotensive and hypertensive individuals. 10, 6, 3
Protein intake:
- 0.8 g/kg/day for most CKD patients 3
- In earlier stages of CKD: 0.8-1.0 g/kg/day 10
- Avoid high protein intake (>1.3 g/kg/day) 6
- Do NOT restrict protein in malnourished, sarcopenic, or cachectic patients 2
Weight management: Modest weight loss beneficially affects blood pressure and metabolic parameters. 10, 2
Smoking cessation is mandatory. 2, 3
Stage-Based Clinical Action Plan
Stages 1-2 (GFR ≥60 mL/min/1.73 m²)
Begin treatment of comorbid conditions, interventions to slow progression, and cardiovascular risk reduction. Control hypertension carefully. 11
Stage 3 (GFR 30-59 mL/min/1.73 m²)
Evaluate and treat complications including anemia, malnutrition, bone disease, neuropathy. These complications rise when GFR declines below 60. 11
Stage 4 (GFR 15-29 mL/min/1.73 m²)
Begin preparation for kidney replacement therapy. Refer to nephrologist for co-management (mandatory when GFR <30). 11
Stage 5 (GFR <15 mL/min/1.73 m²)
Initiate dialysis planning and transplantation evaluation. 11
Monitoring and Evaluation
Test both urine albumin and GFR every 3-6 months to assess progression. 1, 2 Use albumin-to-creatinine ratio in spot urine samples (abnormal if >30 mg/g; sex-specific cutoffs: >17 mg/g men, >25 mg/g women). 11 Two of three specimens over 3-6 months should be abnormal before confirming persistent albuminuria. 5
Measure serum creatinine annually to estimate GFR and stage CKD. 5
Search thoroughly for reversible causes in each patient through history, physical examination, and laboratory evaluation. 11
Critical Pitfalls to Avoid
- Late nephrology referral: Many patients see nephrologists only shortly before dialysis, which is associated with worse outcomes. Refer when GFR <30. 11
- Underdosing RAS inhibitors: Use maximum tolerated doses, not submaximal doses. 1
- Ignoring cardiovascular risk: CVD events are more common than kidney failure in CKD patients. Treat CKD patients as highest-risk group for CVD. 11
- Protein restriction in malnourished patients: This worsens outcomes. 6, 2
- Stopping medications at dialysis initiation: Continue SGLT2 inhibitors and other nephroprotective agents until dialysis or transplant. 2
Additional Considerations
Acidosis correction and uric acid reduction are NOT considered nephroprotective measures according to latest guidelines. 3
Glycemic control in diabetic patients should target HbA1c as close to normal as possible without significant hypoglycemia. 10
Avoid nephrotoxic agents including high-osmolar radiocontrast media and gadolinium-containing contrast when GFR <30 mL/min/1.73 m². 6