When do you start Angiotensin-Converting Enzyme (ACE) inhibitors for patients with diabetes?

When to Start ACE Inhibitors in Diabetes

ACE inhibitors should be initiated in patients with diabetes who have hypertension and albuminuria (urine albumin-to-creatinine ratio ≥30 mg/g creatinine), and should be titrated to the highest approved dose that is tolerated. 1

Indications for ACE Inhibitor Initiation in Diabetes

Primary Indications:

1. Diabetes with hypertension and albuminuria

   • Strong recommendation (1B) for initiating ACE inhibitors or ARBs in patients with diabetes, hypertension, and albuminuria 1
   • These patients should have ACE inhibitors as first-line therapy for hypertension 1

2. Diabetes with albuminuria but normal blood pressure

   • ACE inhibitors may be considered in patients with diabetes, albuminuria, and normal blood pressure 1
   • This is particularly important for patients with urine albumin-to-creatinine ratio ≥30 mg/g creatinine 1

3. Diabetes with hypertension (without albuminuria)

   • ACE inhibitors are recommended first-line therapy for hypertension in people with diabetes and coronary artery disease 1
   • For patients without albuminuria, ACE inhibitors have not been found to afford superior cardioprotection compared to thiazide-like diuretics or dihydropyridine calcium channel blockers 1

Specific Thresholds:

• Blood pressure threshold: Start ACE inhibitor when BP ≥140/90 mmHg 1
• For patients with BP 130-139/80-89 mmHg: Consider lifestyle/behavioral therapy alone for a maximum of 3 months, then add ACE inhibitor if targets not achieved 1
• Albuminuria threshold: Start ACE inhibitor when urine albumin-to-creatinine ratio ≥30 mg/g creatinine 1

Monitoring After ACE Inhibitor Initiation

1. Monitor within 2-4 weeks of initiation or dose increase:

   • Serum creatinine
   • Serum potassium
   • Blood pressure 1

2. Continue ACE inhibitor unless:

   • Serum creatinine rises by more than 30% within 4 weeks following initiation or dose increase
   • Uncontrolled hyperkalemia develops despite medical management
   • Symptomatic hypotension occurs 1

3. Annual monitoring:

   • Serum creatinine/eGFR and serum potassium levels should be monitored at least annually for patients on ACE inhibitors 1

Special Considerations

• Pregnancy: ACE inhibitors are contraindicated during pregnancy. Advise contraception in women receiving ACE inhibitor therapy and discontinue these agents in women who are considering pregnancy or who become pregnant 1

• Hyperkalemia management: Hyperkalemia associated with ACE inhibitor use can often be managed by measures to reduce serum potassium levels rather than immediately decreasing the dose or stopping the medication 1

• Dose titration: ACE inhibitors should be titrated to the highest approved dose that is tolerated to maximize renoprotective effects 1

Common Pitfalls to Avoid

1. Stopping ACE inhibitors prematurely: Many clinicians discontinue ACE inhibitors when serum creatinine rises slightly. However, an increase of up to 30% is acceptable and expected 1

2. Inadequate dose titration: Failing to titrate to maximum tolerated doses reduces the renoprotective benefits 1

3. Not considering ACE inhibitors in normotensive patients with albuminuria: Even patients with normal blood pressure but albuminuria may benefit from ACE inhibitors 1

4. Not monitoring kidney function and potassium: Regular monitoring is essential to prevent complications 1

5. Continuing ACE inhibitors during pregnancy: This can cause fetal damage 1

ACE inhibitors remain a cornerstone therapy in diabetes management, particularly for patients with albuminuria or hypertension, due to their proven benefits in reducing cardiovascular events and slowing the progression of diabetic kidney disease.