What is the management approach for a patient with a decreasing Glomerular Filtration Rate (GFR), potentially due to underlying conditions such as diabetes, hypertension, or cardiovascular disease?

Management of Decreasing GFR

For patients with declining GFR, immediately initiate SGLT2 inhibitors (if eGFR ≥20 mL/min/1.73 m²) and optimize renin-angiotensin system blockade with ACE inhibitors or ARBs, while establishing nephrology referral thresholds based on GFR category and rate of decline. 1

Immediate Assessment and Monitoring Strategy

Classify CKD Stage and Establish Monitoring Frequency

• Determine current GFR category and albuminuria status to stratify risk and guide monitoring intensity using the KDIGO classification system 1
• For GFR 45-59 mL/min/1.73 m² (Stage 3a): Monitor 1-2 times yearly if albuminuria <30 mg/g; increase to 2-3 times yearly if albuminuria 30-299 mg/g 1
• For GFR 30-44 mL/min/1.73 m² (Stage 3b): Monitor 2-4 times yearly depending on albuminuria category 1, 2
• For GFR 15-29 mL/min/1.73 m² (Stage 4): Monitor 3-4 times yearly and refer to nephrology 1, 2

Rule Out Reversible Causes

• Exclude volume depletion or pre-renal azotemia as a cause of acute GFR decline before attributing changes to progressive CKD 2
• Review all medications for drugs that compete with creatinine for tubular secretion or are nephrotoxic 2
• Discontinue NSAIDs and other nephrotoxic agents immediately 2, 3

Pharmacologic Interventions to Slow Progression

SGLT2 Inhibitors (First-Line for Type 2 Diabetes)

• Initiate SGLT2 inhibitor for all patients with type 2 diabetes and eGFR ≥20 mL/min/1.73 m² regardless of albuminuria level to reduce CKD progression and cardiovascular events 1
• For albuminuria ≥200 mg/g: SGLT2 inhibitors have Grade A evidence for reducing CKD progression 1
• For albuminuria <200 mg/g: SGLT2 inhibitors still recommended with Grade B evidence 1
• Expect transient GFR decline up to 25% after initiation due to hemodynamic changes; this is not a reason to discontinue unless decline exceeds 30% 1, 2

Renin-Angiotensin System Blockade

• Prescribe ACE inhibitor or ARB for all patients with albuminuria ≥30 mg/g to slow progression 1, 2
• For albuminuria ≥300 mg/g and/or eGFR <60 mL/min/1.73 m²: ACE inhibitor or ARB is strongly recommended (Grade A) 1
• Do not discontinue for creatinine increases up to 30% in the absence of volume depletion 1, 2
• Monitor serum creatinine and potassium periodically when using these agents 1
• ACE inhibitors or ARBs are NOT recommended for primary prevention in patients with normal blood pressure, normal albuminuria (<30 mg/g), and normal eGFR 1

Nonsteroidal Mineralocorticoid Receptor Antagonists

• Consider finerenone for patients with eGFR ≥25 mL/min/1.73 m² and albuminuria to reduce cardiovascular events and CKD progression (Grade A) 1
• Particularly beneficial for patients with albuminuria who remain at high risk despite SGLT2 inhibitor and ACE inhibitor/ARB therapy 1

GLP-1 Receptor Agonists

• Consider GLP-1 agonist for additional cardiovascular risk reduction in patients with type 2 diabetes and CKD 1

Blood Pressure and Glycemic Control

Blood Pressure Targets

• Target blood pressure <130/80 mmHg for most patients with CKD and diabetes 1, 2
• For patients aged >65 years: Target systolic blood pressure 130-139 mmHg (not <120 mmHg) 1
• Expect to require 3-4 antihypertensive medications to achieve target in advanced CKD 2
• Intensive blood pressure control (<130/80 mmHg) slows progression more effectively than conventional control 4

Glycemic Targets

• Target HbA1c <7.0% for most patients with diabetes and CKD 1, 2
• Consider tighter control (HbA1c <6.5%) for younger patients without hypoglycemia risk 1
• Less stringent targets (HbA1c <8.0%) are appropriate for elderly patients or those with severe comorbidities 1

Dietary and Lifestyle Modifications

• Restrict dietary protein to 0.8 g/kg body weight/day for non-dialysis-dependent CKD stage 3 or higher 1, 2
• Consider further restriction to 0.6 g/kg/day in selected patients under close supervision 2
• Implement structured diabetes self-management education including diet, exercise, and smoking cessation 1

Nephrology Referral Criteria

Mandatory Referral Thresholds

• Refer when eGFR <30 mL/min/1.73 m² (Stage 4) for preparation for kidney replacement therapy 1, 2
• Refer when eGFR <45 mL/min/1.73 m² for coordinated care to slow progression 1, 5
• Immediate referral for eGFR <60 mL/min/1.73 m² in diabetic patients according to ADA guidelines 2

Additional Referral Indications

• Albuminuria ≥300 mg/g with persistent elevation despite treatment 1
• Rapid GFR decline >5 mL/min/1.73 m² per year 1
• Decline in eGFR of 30% or greater over 2 years (strongly associated with ESRD risk) 6
• Uncertainty about etiology of kidney disease or difficult management issues 1

Monitoring for CKD Complications

Laboratory Surveillance

• Screen for anemia, metabolic bone disease, and nutritional impairment as GFR declines 2, 3
• Monitor for hyperkalemia, metabolic acidosis, hyperphosphatemia in advanced CKD 3
• Assess vitamin D deficiency and secondary hyperparathyroidism 3
• Target 30% reduction in albuminuria as a surrogate marker for slowing CKD progression 1

Cardiovascular Risk Management

• Aggressively screen and manage cardiovascular risk factors as CKD patients have markedly elevated cardiovascular mortality 2, 3
• Initiate statin therapy for cardiovascular risk reduction 3

Critical Precautions

• Avoid radiocontrast media whenever possible in patients with declining GFR 2
• Adjust medication dosing for many antibiotics and oral hypoglycemic agents based on GFR 3
• Do not delay nephrology referral even if other interventions are optimized 2
• Changes in GFR >20% on subsequent tests require immediate evaluation 2