What are the recommended blood pressure (BP) control strategies for African Americans with hypertension?

Blood Pressure Control in African Americans

For African Americans with hypertension, initiate treatment with either a thiazide-type diuretic (chlorthalidone 12.5-25 mg daily preferred) or a calcium channel blocker (amlodipine 5-10 mg daily), and plan for combination therapy from the outset since most patients will require two or more medications to achieve target BP <130/80 mmHg. 1, 2

First-Line Monotherapy Selection

Thiazide-type diuretics and calcium channel blockers are significantly more effective than ACE inhibitors, ARBs, or beta-blockers at lowering blood pressure in African Americans. 1, 2

Preferred Initial Agents:

• Chlorthalidone 12.5-25 mg daily is the preferred thiazide due to superior cardiovascular outcome data and longer half-life compared to hydrochlorothiazide 25-50 mg daily 1, 2
• Amlodipine is equally effective as chlorthalidone for BP reduction and cardiovascular outcomes in African Americans 1, 2
• Both agents demonstrate superior efficacy in reducing cardiovascular disease events compared to RAS inhibitors or alpha blockers in this population 1

Critical Pitfall to Avoid:

Do not use ACE inhibitors or ARBs as monotherapy in African Americans - they are significantly less effective at lowering BP in this population 1, 2, 3. Additionally, African Americans have a 3-4 fold higher risk of angioedema with ACE inhibitors compared to whites 4, 1.

Treatment Algorithm Based on Baseline BP

If BP is <15/10 mmHg Above Goal:

• Start with monotherapy: either thiazide-type diuretic OR calcium channel blocker 2
• Increase to full dose after 2-4 weeks if target not achieved 2
• Add second agent (the other first-line class) if BP remains uncontrolled 2

If BP is ≥15/10 mmHg Above Goal:

Start immediately with combination therapy rather than monotherapy 1, 2, 5

Recommended initial combinations: 4, 1

• Low-dose ARB + dihydropyridine calcium channel blocker, OR
• Dihydropyridine calcium channel blocker + thiazide-like diuretic

Escalation to Triple Therapy:

If BP remains uncontrolled on dual therapy, progress to: CCB + thiazide diuretic + ARB/ACE inhibitor 1, 6

Resistant Hypertension (Fourth-Line):

Add spironolactone as the preferred agent, or if not tolerated: eplerenone, amiloride, doxazosin, or beta-blocker 4, 1

Target Blood Pressure and Monitoring

• Target: <130/80 mmHg 4, 6, 2
• Minimum reduction goal: 20/10 mmHg from baseline 4, 6, 2
• Achieve target within 3 months of initiating therapy 4, 6, 2
• If BP remains uncontrolled despite optimized triple therapy, refer to hypertension specialist 6

Special Clinical Scenarios Requiring Modified Approach

Chronic Kidney Disease with Proteinuria:

Include an ACE inhibitor or ARB as part of multidrug regimen (not monotherapy) 1, 2. This is one of the few scenarios where RAS inhibitors are specifically indicated in African Americans, but always combined with a diuretic or CCB 4.

Heart Failure:

Add beta-blocker to the regimen 1, 2. Post-myocardial infarction patients also benefit from beta-blocker therapy, with a 28% reduction in mortality demonstrated in African Americans 4.

Diabetes Mellitus:

The same first-line recommendations apply (thiazide or CCB) 2. Most diabetic African American patients are high-risk and should start drug treatment immediately rather than waiting 3-6 months 4

Why Most African Americans Require Combination Therapy

The overwhelming majority of African American hypertensive patients will require combination therapy to maintain BP consistently below target levels 1, 5. This is due to: 4, 5, 7

• Higher baseline BP levels at presentation
• Earlier onset and greater severity of hypertension
• Higher prevalence of resistant hypertension
• Greater burden of comorbidities (obesity, diabetes, chronic kidney disease)

Practical Implementation Strategy

Use single-pill combinations to improve adherence, though be aware these may contain lower-than-optimal doses of the thiazide component 4. Once-daily dosing regimens should be prioritized 4.

Confirm Diagnosis Before Treatment:

• Use validated automated upper arm cuff with appropriate cuff size 4, 6
• Measure BP in both arms; use the arm with higher reading 4, 6
• Confirm office BP ≥140/90 mmHg with home BP ≥135/85 mmHg or 24-hour ambulatory BP ≥130/80 mmHg 4, 6

Lifestyle Modifications Are Essential:

Weight reduction, sodium restriction (particularly important given high salt content in some traditional diets), increased physical activity, and the low-sodium DASH diet show greater BP reductions in African Americans than other demographic groups 4, 5. However, socioeconomic barriers may make these modifications challenging 4, 7.

Key Differences from Non-Black Patients

Unlike non-Black patients who typically start with ACE inhibitors or ARBs, African Americans should start with either a thiazide diuretic or calcium channel blocker 4. The racial differences in BP response to ACE inhibitors and ARBs are abolished when these agents are combined with a diuretic, which is why they can be added as second or third-line agents 4.