How to Treat Hypertension in African-Americans

Nurse taking man's blood pressure
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High blood pressure presents a unique problem in the African-American population. African-Americans have a high incidence of hypertension. Even more significantly, hypertension in blacks often occurs at an earlier age compared to other major race or ethnicity groups. African-Americans also have higher rates of other diseases like obesity and diabetes that make hypertension even more difficult to control.

Most African-American people with high blood pressure need more than one medication to reach their blood pressure goal.

JNC 8 Recommendations

The Joint National Committee (JNC) 8 is a panel of experts who reviewed all of the evidence available to support treatment recommendations for hypertension. In addition to addressing treatment of hypertension in the general population, the JNC 8 made specific recommendations for the best treatment for hypertension in blacks. The evidence considered by the JNC8 included randomized clinical trials, which provide the strongest scientific support for clinical practice.

In general, JNC 8 suggested that all hypertensive people who are 60 years or older should be treated to reach a blood pressure goal of less than 150/90 mm Hg. People younger than 60 should try to reach a blood pressure goal of less than 140/90 mm Hg. Anyone who has diabetes or chronic kidney disease should also maintain a blood pressure less than 140/90 mm Hg.

Treatment Recommendations

Although JNC 8 recommends beginning treatment with an angiotensin-converting enzyme inhibitor, angiotensin receptor blocker, calcium channel blocker, or a thiazide-type diuretic for the non-black population, there is evidence that blacks with hypertension, including those who have diabetes, should begin treatment with a calcium channel blocker or a thiazide-type diuretic.

Blacks with chronic kidney disease can begin treatment with an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker, either alone or combined with a calcium channel blocker or a thiazide-type diuretic. ACEIs and ARBs have been shown in some studies to improve kidney outcomes in patients with chronic kidney disease. When treating hypertension in patients, JNC 8 recommendations take into consideration the best solution to limit damage to organs like the kidney or heart in patients.

This is because ACEIs and ARBs work on the renin-angiotensin system of blood pressure control, and African-Americans with hypertension appear to have lower levels of activity in that system, which makes them less responsive. African-Americans with hypertension also have abnormal blood vessel constriction as a result of lower levels of the chemical nitric oxide.

Risk Factors for Hypertension in African-Americans vs. Other Populations

Salt sensitivity occurs more frequently in African-Americans.This refers to a rise in blood pressure in response to salt. One reason may be that salt sensitivity is more common in obese people and there is a greater prevalence of obesity in the African-American population.

In fact, one in six African-American women are considered extremely obese, which is four times the proportion compared to white women or Hispanic women. Obesity also results in resistance to medications used to treat high blood pressure. It can result in sleep apnea or other sleep problems that contribute to the development of hypertension.

Difficulty Controlling Blood Pressure

In addition to having more difficulty with blood pressure control, African-Americans who have hypertension have a higher incidence of characteristics that are associated with resistant hypertension, including diabetes, obesity, and complications related to damage caused by high blood pressure in organs like the kidney.

"Resistant hypertension" refers to blood pressure that is not adequately controlled with three different drugs (in three different antihypertensive classes, including a diuretic).

Important Lifestyle Changes Required

There are a number of important lifestyle choices that must be part of any comprehensive approach to treating hypertension, particularly in African-Americans with difficult-to-control blood pressure. These include a low-salt diet, increased physical activity, alcohol restriction, and weight loss. In fact, diet can lower blood pressure as much as a single-drug therapy. The International Society on Hypertension in blacks recommends that all African-Americans with a blood pressure of more than 115/75 mm Hg begin lifestyle modification in order to slow progression of development of hypertension and cardiovascular disease.