When should an Angiotensin Receptor Blocker (ARB) be started in a person with diabetes?

When to Start ARBs in Patients with Diabetes

ARBs should be initiated in patients with diabetes who have hypertension (blood pressure ≥140/90 mmHg) immediately along with lifestyle modifications, and in those with blood pressure 130-139/80-89 mmHg after a 3-month trial of lifestyle modifications if target blood pressure (<130/80 mmHg) is not achieved. 1, 2

Indications for ARB Initiation in Diabetes

• ARBs are recommended as first-line therapy for hypertension in patients with diabetes, especially those with albuminuria or renal insufficiency 1
• Immediate initiation of ARBs along with lifestyle modifications is indicated when blood pressure is ≥140/90 mmHg 1, 2
• For patients with blood pressure 130-139/80-89 mmHg, start with lifestyle modifications for up to 3 months, then add ARBs if target blood pressure is not achieved 2
• ARBs are particularly indicated in patients with diabetes who have coronary artery disease or albumin-to-creatinine ratio ≥30 mg/g creatinine 1
• ARBs are strongly recommended for patients with urine albumin-to-creatinine ratio ≥300 mg/g creatinine 1

Target Blood Pressure Goals

• The general target blood pressure for most patients with diabetes is <130/80 mmHg 1
• A less stringent blood pressure target (<140/90 mmHg) may be appropriate for elderly patients and those with severe coronary heart disease 1
• Blood pressure should be measured at every routine diabetes visit 2

Dosing Recommendations

• The usual starting dose for losartan is 50 mg once daily 3
• The dose can be increased to a maximum of 100 mg once daily based on blood pressure response 3
• For nephropathy in type 2 diabetic patients, start with 50 mg once daily and increase to 100 mg once daily as needed 3
• In patients with possible intravascular depletion (e.g., on diuretic therapy), a lower starting dose of 25 mg is recommended 3
• In patients with mild-to-moderate hepatic impairment, start with 25 mg once daily 3

Benefits Beyond Blood Pressure Control

• ARBs provide renoprotection beyond their blood pressure-lowering effects 2, 4
• ARBs prevent the development of clinical proteinuria in microalbuminuric patients 5
• ARBs delay the progression of nephropathy toward end-stage renal failure in patients with overt nephropathy 3, 5
• ARBs reduce the risk of doubling of serum creatinine by 25% and end-stage renal disease by 29% in patients with type 2 diabetes and nephropathy 3
• ARBs significantly reduce proteinuria by an average of 34%, an effect evident within 3 months of starting therapy 3

Treatment Strategy Considerations

• Multiple antihypertensive agents are usually required to achieve blood pressure targets in patients with diabetes 1, 6
• If ARBs are not tolerated, ACE inhibitors can be substituted as they have similar benefits 2, 5
• Avoid combining ARBs with ACE inhibitors due to increased risk of adverse effects without additional benefits 2
• For patients requiring multiple medications, a thiazide-like diuretic or dihydropyridine calcium channel blocker can be added to ARB therapy 1
• If a patient has resistant hypertension (BP ≥140/90 mmHg despite three antihypertensive medications including a diuretic), consider adding a mineralocorticoid receptor antagonist 1

Special Considerations

• ARBs are contraindicated during pregnancy 1
• When treating patients with serum creatinine >2 mg/dL, start ARBs at a lower dose and monitor serum creatinine and potassium every 2 weeks 7
• In patients with eGFR <30 mL/min/1.73m², use loop diuretics rather than thiazide diuretics when additional agents are needed 1
• The compelling benefits of ARBs in diabetic patients with albuminuria or renal insufficiency provide additional rationale for their use as first-line therapy 1