Is amlodipine a good choice for black people to treat high blood pressure?

Recent clinical practice guidelines emphasize the need for tailored therapy for black people, because the available evidence suggests that black people have a better response to treatment with calcium channel blockers (CCBs), like amlodipine, and diuretics, like chlorthalidone, than they do to angiotensin-converting enzyme inhibitors (ACEIs), angiotensin receptor blockers (ARBs) and beta-blockers.^1,2 This difference appears to be true when antihypertensive medication is given as monotherapy³ and combination therapy.⁴ 

More research is needed to evaluate the efficacy of amlodipine, specifically, among black people. There is, however, good evidence to support the effectiveness of other drugs in the same class as amlodipine in controlling blood pressure and in reducing the risk of cardiovascular events in black populations, as compared to other antihypertensives.^3,5–7

The Avoiding Cardiovascular Events through Combination Therapy in Patients Living with Systolic Hypertension trial studied the effectiveness of combination therapy in 11,506 patients with hypertension, 1,416 of whom were black.⁴ Combination therapy with benazepril (an ACEI) plus amlodipine (a CCB) was compared with benazepril plus hydrochlorothiazide (a diuretic). Blood pressure-lowering was comparable in the two groups, but the benazepril-amlodipine combination therapy was significantly more effective at lowering the risk of cardiovascular events and death from cardiovascular causes. Among all participants, black and non-black, there were 552 cardiovascular events in the benazepril–amlodipine group (9.6%) and 679 in the benazepril–hydrochlorothiazide group (11.8%), a relative risk reduction of 19.6% (95% confidence interval [CI] [0.72 – 0.90], p<0.001). When analyzed separately, results were similar among blacks alone.¹

In the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial, a clinical study specifically designed to compare the efficacy of different classes of antihypertensive agents in preventing cardiovascular outcomes, the ACEI lisinopril was less effective than monotherapy with the thiazide-type diuretic chlorthalidone or amlodipine in lowering BP and in preventing many major adverse clinical outcomes in black participants.⁸ When patient outcomes were evaluated eight years after the study’s conclusion, amlodipine was associated with a higher risk of heart failure among black patients, when compared with chlorthalidone.^9,10

While ACEIs and ARBs have been shown to be less effective than CCBs and diuretics in reducing blood pressure and cardiovascular morbidity and mortality among black people, they have also been shown to be more effective in slowing the progression of kidney disease in people with hypertension, including blacks.^11–13

Further study will clarify the best practice for antihypertensive therapy based on clinical differences among people of different racial groups.¹⁴

^References

1. Flack JM, Sica DA, Bakris G, et al. Management of high blood pressure in blacks: An update of the International Society on Hypertension in Blacks consensus statement. Hypertension 2010; 56 (5): 780-800.
2. Weber MA, Schiffrin EL, White WB, et al. Clinical practice guidelines for the management of hypertension in the community a statement by the American Society of Hypertension and the International Society of Hypertension. J Hypertens 2014; 32 (1): 3-15.
3. Brewster LM, van Montfrans GA, Kleijnen J. Systematic review: antihypertensive drug therapy in black patients. Ann Intern Med 2004; 141 (8): 614-627.
4. Jamerson K, Weber MA, Bakris GL, et al. Benazepril plus amlodipine or hydrochlorothiazide for hypertension in high-risk patients. N Engl J Med 2008; 359 (23): 2417-2428.
5. Materson BJ, Reda DJ, Cushman WC, et al. Single-drug therapy for hypertension in men. A comparison of six antihypertensive agents with placebo. The Department of Veterans Affairs Cooperative Study Group on Antihypertensive Agents. N Engl J Med 1993.
6. Materson BJ, Reda DJ CW. Department of Veterans Affairs single-drug therapy of hypertension study. Revised figures and new data. Department of Veterans Affairs Cooperative Study Group on Antihypertensive Agents. Am J Hypertens 1995; 8 (2): 189-192.
7. Sareli P, Radevski I V, Valtchanova ZP, et al. Efficacy of different drug classes used to initiate antihypertensive treatment in black subjects: results of a randomized trial in Johannesburg, South Africa. Arch Intern Med 2001; 161 (7): 965-971.
8. Furberg CD, Wright JT, Davis BR, et al. Major outcomes in high-risk hypertensive patients randomized to angiotensin-converting enzyme inhibitor or calcium channel blocker vs diuretic: the antihypertensive and lipid-lowering treatment to prevent heart attack trial (ALLHAT). J Am Med Assoc 2002; 288 (23): 2981-2997.
9. Still CH, Ferdinand KC, Ogedegbe G, Wright JT. Recognition and management of hypertension in older persons: focus on African Americans. J Am Geriatr Soc 2015; 63 (10): 2130-2138.
10. Wright JTJ, Dunn JK, Cutler JA, et al. Outcomes in hypertensive black and nonblack patients treated with chlorthalidone, amlodipine, and lisinopril. JAMA 2005; 293 (13): 1595-1608.
11. Brenner BM, Cooper ME, de Zeeuw D, et al. Effects of losartan on renal and cardiovascular outcomes in patients with type 2 diabetes and nephropathy. N Engl J Med 2001; 345 (12): 861-869.
12. de Zeeuw D, Ramjit D, Zhang Z, et al. Renal risk and renoprotection among ethnic groups with type 2 diabetic nephropathy: a post hoc analysis of RENAAL. Kidney Int 2006; 69 (9): 1675-1682.
13. Wright JTJ, Bakris G, Greene T, et al. Effect of blood pressure lowering and antihypertensive drug class on progression of hypertensive kidney disease: results from the AASK trial. JAMA 2002; 288 (19): 2421-2431.
14. Whelton PK, Einhorn PT, Muntner P, et al. Research needs to improve hypertension treatment and aontrol in African Americans. Hypertension 2016; 68 (5): 1066-1072.