What are the KDIGO (Kidney Disease: Improving Global Outcomes) guidelines for managing hypertension in patients with impaired renal function?

KDIGO Guidelines for Managing Hypertension in Chronic Kidney Disease

The 2021 KDIGO guidelines recommend a target systolic blood pressure of <120 mmHg for adults with high blood pressure and CKD when tolerated, using standardized office BP measurement techniques. 1

Blood Pressure Measurement

Standardized Measurement Protocol

• Use automated oscillometric BP device (preferred over manual)
• Ensure proper patient preparation:
  • Empty bladder before measurement
  • No talking during rest period or measurement
  • Patient should be seated with back supported
  • Feet flat on floor, legs uncrossed
  • Arm supported at heart level
• Take multiple readings (at least 2-3) with 1-2 minute intervals
• Average the readings for clinical decision making

Out-of-Office BP Monitoring

• Home BP monitoring is recommended as complement to standardized office readings 1
• 24-hour ambulatory BP monitoring (ABPM) is particularly valuable for children with CKD 1

Medication Recommendations by Patient Population

Adults with CKD without Diabetes

• For severely increased albuminuria (>300 mg/24h): Start with ACEi or ARB (strong recommendation, 1B) 1, 2
• For moderately increased albuminuria (30-300 mg/24h): Consider ACEi or ARB (weaker recommendation, 2C) 1, 2
• For no albuminuria: RASi (ACEi or ARB) may still be reasonable 1

Adults with CKD with Diabetes

• For moderately-to-severely increased albuminuria (≥30 mg/24h): Start with ACEi or ARB (strong recommendation, 1B) 1, 2

Kidney Transplant Recipients

• Target BP <130/80 mmHg using standardized measurement 1
• First-line agents: dihydropyridine calcium channel blocker (CCB) or ARB (1C) 1

Children with CKD

• Target 24-hour mean arterial pressure by ABPM ≤50th percentile for age, sex, and height (2C) 1
• First-line therapy: ACEi or ARB 1, 2
• Monitor BP once yearly with ABPM and every 3-6 months with standardized auscultatory office BP 1

Medication Management

Dosing and Monitoring

• Use highest approved dose of RASi that is tolerated 1
• Check BP, serum creatinine, and potassium within 2-4 weeks after initiation or dose increase 1, 2
• Continue ACEi/ARB unless serum creatinine rises >30% within 4 weeks of starting treatment 1, 2

When to Reduce Dose or Discontinue RASi

• Symptomatic hypotension
• Uncontrolled hyperkalemia despite treatment
• To reduce uremic symptoms in advanced kidney failure (eGFR <15 ml/min/1.73m²) 1

Important Cautions

• Avoid any combination of ACEi, ARB, and direct renin inhibitor (strong recommendation, 1B) 1
• Mineralocorticoid receptor antagonists can help with resistant hypertension but may cause hyperkalemia or kidney function decline, especially in advanced CKD 1

Lifestyle Interventions

• Sodium restriction: <2g sodium per day (<5g sodium chloride) 1, 2
• Physical activity: At least 150 minutes per week of moderate-intensity activity 1, 2

Implementation Challenges

The 2021 KDIGO target of <120 mmHg systolic BP represents a significant shift from previous guidelines. This target is based primarily on the SPRINT trial and its CKD subgroup analysis 1, 3. Some experts have raised concerns about:

1. Difficulty implementing standardized BP measurement in routine clinical practice 1
2. Potential adverse events in frail or multimorbid CKD patients 1
3. Achievability of this target in advanced CKD patients 4

A US study found that 69.5% of adults with CKD would be eligible for more intensive BP lowering under the 2021 KDIGO guideline, compared to 49.8% under the 2012 guideline 5. However, the prevalence of apparent treatment-resistant hypertension increases with CKD severity, affecting up to 60% of patients with advanced CKD 4.

The KDOQI US Commentary generally agreed with the KDIGO recommendations while highlighting the weak evidence base, especially for patients with diabetes and advanced CKD 6.

Key Pitfalls to Avoid

• Do not apply the <120 mmHg target to non-standardized BP measurements 1
• Do not combine multiple RAS blockers (ACEi, ARB, DRI) 1
• Do not discontinue RASi prematurely for small, expected increases in creatinine (<30%) 1
• Do not overlook hyperkalemia management strategies before reducing RASi dose 1
• Do not neglect lifestyle modifications alongside pharmacological therapy 1, 2