What are the implications for an African American patient with Chronic Kidney Disease (CKD) taking an Angiotensin Receptor Blocker (ARB) inhibitor?

From the Guidelines

African American patients with chronic kidney disease (CKD) should be treated with a combination of antihypertensive medications, including a thiazide diuretic or a calcium channel blocker (CCB), as these are more effective in lowering blood pressure and reducing cardiovascular disease (CVD) events than renin-angiotensin-aldosterone system (RAS) inhibitors, such as angiotensin receptor blockers (ARBs) 1. However, for African American patients with CKD and diabetes, RAS inhibitors, including ARBs, are recommended and should be titrated to the maximal tolerated dose, with close monitoring of serum potassium and serum creatinine levels within 2 to 4 weeks of initiation of or change in dose 1. The choice of antihypertensive medication should be individualized, taking into account the patient's specific clinical characteristics, such as the presence of diabetes, hypertension, and albuminuria. Some key points to consider when treating African American patients with CKD include:

• Thiazide diuretics or CCBs are more effective in lowering blood pressure and reducing CVD events than RAS inhibitors or beta blockers 1.
• RAS inhibitors, including ARBs, are recommended for patients with CKD and diabetes, and should be titrated to the maximal tolerated dose 1.
• Combination therapy with ACE inhibitors and ARBs is harmful and should be avoided in patients with diabetes and CKD 1.
• Regular monitoring of kidney function and potassium levels is essential, particularly within 1-2 weeks of starting therapy or dose adjustments.
• ARBs work by blocking the renin-angiotensin-aldosterone system, reducing intraglomerular pressure and proteinuria, which helps preserve kidney function.
• While ACE inhibitors offer similar benefits, ARBs typically cause fewer side effects like cough, making them well-tolerated options for long-term therapy in CKD management.

From the FDA Drug Label

Losartan may be administered with other antihypertensive agents. In the LIFE study, Black patients with hypertension and left ventricular hypertrophy treated with atenolol were at lower risk of experiencing the primary composite endpoint compared with Black patients treated with losartan The primary endpoint was the first occurrence of stroke, myocardial infarction or cardiovascular death, analyzed using an intention-to-treat (ITT) approach In the subgroup of Black patients (n=533,6% of the LIFE study patients), there were 29 primary endpoints among 263 patients on atenolol (11%, 26 per 1000 patient-years) and 46 primary endpoints among 270 patients (17%, 42 per 1000 patient-years) on losartan This finding could not be explained on the basis of differences in the populations other than race or on any imbalances between treatment groups. However, the LIFE study provides no evidence that the benefits of losartan on reducing the risk of cardiovascular events in hypertensive patients with left ventricular hypertrophy apply to Black patients Patients with renal insufficiency have elevated plasma concentrations of losartan and its active metabolite compared to subjects with normal renal function. No dose adjustment is necessary in patients with renal impairment unless a patient with renal impairment is also volume depleted

The use of losartan in an African American patient with CKD (Chronic Kidney Disease) may not provide the same level of cardiovascular protection as it does in other populations, particularly in terms of reducing the risk of stroke and myocardial infarction.

• The LIFE study found that Black patients with hypertension and left ventricular hypertrophy treated with losartan had a higher risk of experiencing the primary composite endpoint compared to those treated with atenolol.
• Additionally, patients with renal insufficiency may have elevated plasma concentrations of losartan and its active metabolite, but no dose adjustment is necessary unless the patient is also volume depleted 2.
• It is essential to carefully consider the potential benefits and risks of using losartan in this patient population and to closely monitor their renal function and blood pressure.
• The patient's CKD should be managed according to established guidelines, and other antihypertensive agents may be considered in addition to or instead of losartan.

From the Research

African American with CKD taking ARB inhibitor

• The use of Angiotensin II receptor antagonists (ARBs) such as losartan has been shown to have a renoprotective effect in patients with chronic kidney disease (CKD) and hypertension 3, 4.
• A study found that losartan reduced proteinuria in patients with CKD and hypertension, indicating its potential to slow the progression of kidney disease 3.
• Another study found that losartan retarded the progression of advanced renal insufficiency in patients with CKD, even when treatment was initiated late in the course of the disease 4.
• In terms of treatment preferences, African American patients with CKD often have limited knowledge of renal replacement therapy options and rely on their doctors for treatment decisions 5.
• Combination therapy with an ARB and a calcium channel blocker or diuretic may be effective in controlling blood pressure and maintaining renal function in patients with CKD 6.
• However, it is essential to note that African Americans with CKD face many barriers to self-care and preparation for end-stage renal disease, including limited knowledge of their disease and treatment options 7, 5.