From the Guidelines
ACE inhibitors are recommended for patients with diabetes due to their renal protective effects and cardiovascular benefits, as evidenced by the most recent study in 2024 1. The use of ACE inhibitors in patients with diabetes mellitus (DM) has been extensively studied, and the current evidence suggests that they are beneficial in reducing proteinuria, slowing the progression of diabetic nephropathy, and lowering blood pressure.
- Common ACE inhibitors used in diabetic patients include lisinopril (10-40 mg daily), ramipril (2.5-10 mg daily), and enalapril (5-40 mg daily).
- These medications work by blocking the conversion of angiotensin I to angiotensin II, reducing vasoconstriction and aldosterone secretion.
- When starting an ACE inhibitor, it is essential to monitor kidney function and potassium levels at baseline and within 1-2 weeks of initiation, as recommended by the 2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA guideline 1.
- Side effects may include dry cough, angioedema, hyperkalemia, and acute kidney injury.
- If a cough develops, consider switching to an angiotensin receptor blocker (ARB) like losartan or valsartan, which provide similar benefits without causing cough, as suggested by the 2016 American Diabetes Association standards of medical care in diabetes 1.
- ACE inhibitors are particularly beneficial for diabetic patients with hypertension, albuminuria, or established cardiovascular disease, as they have been shown to reduce the risk of major cardiovascular events, myocardial infarction, stroke, and albuminuria progression, as demonstrated by the ALLHAT trial 1 and the 2024 Diabetes Care study 1.
From the Research
Effect of ACE Inhibitors on Patients with Diabetes Mellitus
- ACE inhibitors have a pre-eminent place in controlling the complications of diabetes mellitus, particularly in reducing micro- and macrovascular complications 2.
- These inhibitors not only act as potent antihypertensive agents but also demonstrate a specific 'organ-protective' effect, providing function and tissue protection for considered organs such as the kidneys, heart, and to a lesser extent, eyes and peripheral nerves 2.
- The renin-angiotensin-aldosterone system plays a crucial role in increasing the micro- and macrovascular complications in patients with diabetes mellitus, and ACE inhibitors have been shown to improve kidney, heart, and peripheral nerve function in these patients 2, 3.
Renal Protective Effects of ACE Inhibitors
- ACE inhibitors may provide a renal protective effect in addition to their systemic antihypertensive effects due to their favorable intrarenal hemodynamic effects, particularly the reduction of glomerular capillary pressure 3.
- Clinical trials have evaluated the effect of ACE inhibition on the progression of renal insufficiency in hypertensives and diabetics, with favorable results potentially leading to a significant decrease in the morbidity and mortality associated with hypertension 3.
- A 15-year cohort study found that ACE inhibitors and angiotensin II receptor blockers (ARBs) have similar renoprotective effects, but ACE inhibitors might provide additional renoprotective effects among patients with cardiovascular disease or chronic kidney disease 4.
Comparative Effectiveness of ACE Inhibitors and ARBs
- Studies have compared the effectiveness of ACE inhibitors and ARBs in patients with diabetes, with some trials suggesting that ARBs are more effective in preventing the development of clinical proteinuria and delaying the progression of nephropathy in type 2 diabetic patients 5.
- The IRMA, IDNT, and RENAAL trials have demonstrated that ARBs are effective in reducing progression toward end-stage renal failure (ESRF) in type 2 diabetic patients with overt nephropathy, independently of changes in blood pressure 5.
- The ONTARGET trial has shown that the ARB telmisartan is as effective as the ACE-inhibitor ramipril in cardiovascular protection in a high-risk, ACE-tolerant population 6.