JNC 8 and Hypertension

What's New in Hypertension Research

New Hypertension Guidelines
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Hypertension is a major preventable factor in disease and death in the United States that contributes to stroke, kidney disease, and heart attacks. It's critical to detect it early and treat it, in order to prevent serious complications. The Joint National Commission on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure has issued some new recommendations based on scientific evidence.

What is JNC 8?

You may have heard that there are new guidelines for the management of high blood pressure in adults. These guidelines were published by the 8th Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure, known as JNC 8. The guidelines were created after a committee of experts synthesized all available scientific evidence and they were updated to provide guidance for doctors for the management of hypertension. JNC 8 recommends thresholds for treatment of high blood pressure, blood pressure goals, and evidence-based medication therapy.

Blood Pressure Thresholds and Targets

Studies show that lowering blood pressure in adults with hypertension by 10 mm Hg can reduce the risk of death from cardiovascular disease and stroke by 25% to 40%. The evidence shows that adults who are younger than 60 years of age should begin medication when the systolic blood pressure reading (the top number) is 140 mm Hg or higher or when the diastolic blood pressure reading is 90 mm Hg or higher.

In adults older than 60 years of age, treatment should begin if the systolic pressure is 150 mm Hg or higher and if the diastolic pressure is 90 mm Hg or higher. Patients who begin treatment should use these numbers as their target goals. People who have diabetes or chronic disease should also use these targets, since JNC 8 found no evidence that maintaining a lower blood pressure improves health outcomes in these two groups.

Medication Recommendations for Initial Treatment

JNC 8 changed the medication recommendations for initial treatment of hypertension, from 5 drug classes to 4 recommended classes. JNC 8 refined treatment recommendations to four classes of medication:

  • Angiotensin converting enzyme inhibitors (ACEI)
  • Angiotensin receptor blockers (ARB)
  • Diuretics
  • Calcium channel blockers (CCB)

JNC 8 also reviewed the evidence carefully to make specific recommendations of medication for subgroups based on race and the presence of diabetes or chronic kidney disease. There is ample evidence that there are racial differences in the response to certain common classes of blood pressure medication.The final recommendations are:

  • General nonblack population (with or without diabetes) should begin therapy with and ACEI, ARB, CCB, or thiazide-type diuretic (i.e., hydrochlorothiazide.
  • General black population (with or without diabetes) should use a CCB or thiazide type diuretic for initial treatment of hypertension.
  • Patients with chronic kidney disease over the age of 18 should use an ACEI or ARB as initial therapy or add-on therapy, since this has been shown to improve kidney outcomes. This applies to black and non-black populations.

    When to Increase the Dose or Add a New Drug

    JNC 8 recommends an increase in the initial drug dose or addition of a second drug from one of the recommended drug classes for your subgroup if you are not able to reach your blood pressure target within a month. If an increase in dose or addition of a new drug does not reduce your blood pressure to your target goal, then your doctor should add a third drug from one of the recommended classes. However, ACEIs and ARBs should not be used together. Some patients may require the addition of a drug from another class.

    Other Classes of Antihypertension Drugs

    There are times when patients have another reason to take a drug from a class that is not specifically mentioned in the JNC 8 recommendations. For example, beta-blockers have been shown to improve survival in patients with heart failure, so they are a good choice for reduction of blood pressure in patients with congestive heart failure. Patients with benign prostatic hypertrophy often take a class of drugs known as alpha blockers to reduce their symptoms. These medicines were initially developed to treat high blood pressure, but they also relax the prostate and bladder neck, allowing urine to flow freely. Alpha-blockers are a good choice for treatment of hypertension in men with BPH.

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