New hypertension guidelines: One size fits most?
ABSTRACTThe report of the panel appointed to the eighth Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 8) is more evidence-based and focused than its predecessors, outlining a management strategy that is simpler and, in some instances, less aggressive. It has both strengths and weaknesses.
KEY POINTS
- JNC 8 focuses on three main questions: when to begin treatment, how low to aim for, and which antihypertensive medications to use. It does not cover many topics that were included in JNC 7.
- In patients age 60 or older, JNC 8 recommends starting antihypertensive treatment if the blood pressure is 150/90 mm Hg or higher, with a goal of less than 150/90.
- For everyone else, including people with diabetes or chronic kidney disease, the threshold is 140/90 mm Hg, and the goal is less than 140/90.
- The recommended classes of drugs for initial therapy in nonblack patients without chronic kidney disease are thiazide-type diuretics, calcium channel blockers, angiotensin-converting enzyme (ACE) inhibitors, and angiotensin receptor blockers (ARBs), although the last two classes should not be used in combination.
- For black patients, the initial classes of drugs are diuretics and calcium channel blockers; patients with chronic kidney disease should receive an ACE inhibitor or ARB.
Recommendation 5: < 140/90 for people with diabetes
In patients with diabetes who are age 18 and older, JNC 8 says to start drug treatment at a systolic pressure of 140 mm Hg or higher or diastolic pressure of 90 mm Hg or higher, and treat to goal systolic pressure of less than 140 mm Hg and a diastolic pressure of less than 90 mm Hg.
Strength of recommendation—expert opinion (grade E).
Comments. Moderate-quality evidence showed cardiovascular, cerebrovascular, and mortality outcome benefits with treatment to a systolic goal of less than 150 mm Hg in patients with diabetes and hypertension.
The panel found no randomized controlled trials that compared a treatment goal of less than 140 mm Hg with one of less than 150 mm Hg for outcome benefits, but decided to base its recommendations on the results of the Action to Control Cardiovascular Risk in Diabetes—Blood-pressure-lowering Arm (ACCORD-BP) trial.15 The control group in this trial had a goal systolic pressure of less than 140 mm Hg and had similar outcomes compared with a lower goal.
The panel found no evidence to support a lower blood pressure goal (< 130/80) as in JNC 7. ACCORD-BP showed no differences in outcomes with a systolic goal lower than 140 mm Hg vs lower than 120 mm Hg except for a small reduction in stroke, and the risks of trying to achieve intensive lowering of blood pressure may outweigh the benefit of a small reduction in stroke.12 There was no evidence for a goal diastolic pressure below 80 mm Hg.
Recommendation 6: In nonblack patients, start with a thiazide-type diuretic, calcium channel blocker, ACE inhibitor, or ARB
In the general nonblack population, including those with diabetes, initial drug treatment should include a thiazide-type diuretic, calcium channel blocker, ACE inhibitor, or ARB.
Strength of recommendation—moderate (grade B).
Comments. All these drug classes had comparable outcome benefits in terms of rates of death, cardiovascular disease, cerebrovascular disease, and kidney disease, but not heart failure. For improving heart failure outcomes, thiazide-type diuretics are better than ACE inhibitors, which in turn are better than calcium channel blockers.
Thiazide-type diuretics (eg, hydrochlorothiazide, chlorthalidone, and indapamide) were recommended as first-line therapy for most patients in JNC 7, but they no longer carry this preferred status in JNC 8. In addition, the panel did not address preferential use of chlorthalidone as opposed to hydrochlorothiazide, or the use of spironolactone in resistant hypertension.
The panel did not recommend beta-blockers as first-line therapy because there were no differences in outcomes (or insufficient evidence) compared with the above medication classes; additionally, the Losartan Intervention for Endpoint Reduction in Hypertension study16 reported a higher incidence of stroke with a beta-blocker than with an ARB. However, JNC 8 did not consider randomized controlled trials in specific nonhypertensive populations such as patients with coronary artery disease or heart failure. We believe decisions should be individualized as to the use of beta-blockers in these two conditions.
The panel recommended the same approach in patients with diabetes, as there were no differences in major cardiovascular or cerebrovascular outcomes compared with the general population.
Recommendation 7: In black patients, start with a thiazide-type diuretic or calcium channel blocker
In the general black population, including those with diabetes, JNC 8 recommends starting drug treatment with a thiazide-type diuretic or a calcium channel blocker.
Strength of recommendation—moderate (grade B) for the general black population; weak (grade C) for blacks with diabetes.
Comments. In the black subgroup in the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack trial (ALLHAT),17 a thiazide-type diuretic (chlorthalidone) was better than an ACE inhibitor (lisinopril) in terms of cerebrovascular, heart failure, and composite outcomes, but similar for mortality rates and cardiovascular, and kidney outcomes. Also in this subgroup, a calcium channel blocker (amlodipine) was better than the ACE inhibitor for cerebrovascular outcomes (there was a 51% higher rate of stroke with the ACE inhibitor as initial therapy than with the calcium channel blocker); the ACE inhibitor was also less effective in reducing blood pressure in blacks than the calcium channel blocker.
For improving heart failure outcomes, the thiazide-type diuretic was better than the ACE inhibitor, which in turn was better than the calcium channel blocker.
Evidence for black patients with diabetes (graded as weak) was extrapolated from ALLHAT, in which 46% had diabetes.17 We would consider using an ACE inhibitor or ARB in this population on an individual basis, especially if the patient had proteinuria.
Recommendation 8: ACEs and ARBs for chronic kidney disease
In patients age 18 and older with chronic kidney disease, irrespective of race, diabetes, or proteinuria, initial or add-on drug treatment should include an ACE inhibitor or ARB to improve kidney outcomes.
Strength of recommendation—moderate (grade B).
Comments. Treatment with an ACE inhibitor or ARB improves kidney outcomes in patients with chronic kidney disease. But in this population, these drugs are no more beneficial than calcium channel blockers or beta-blockers in terms of cardiovascular outcomes.
No randomized controlled trial has compared ACE inhibitors and ARBs for cardiovascular outcomes in chronic kidney disease, and these drugs have similar effects on kidney outcomes.
The panel did not make any recommendations about direct renin inhibitors, as there were no eligible studies demonstrating benefits on cardiovascular or kidney outcomes.
In black patients with chronic kidney disease and proteinuria, the panel recommended initial therapy with an ACE inhibitor or ARB to slow progression to end-stage renal disease (contrast with Recommendation 7).
In black patients with chronic kidney disease and no proteinuria, the panel recommended choosing from a thiazide-type diuretic, calcium channel blocker, ACE inhibitor, or ARB. If an ACE inhibitor or ARB is not used as initial therapy, then one can be added on as a second-line medication (contrast with Recommendation 7).
The panel found no evidence to support this recommendation in people over age 75 and noted that although an ACE inhibitor or ARB may be beneficial in this group, a thiazide-type diuretic or calcium channel blocker can be considered.
Recommendation 9: If not at goal, step up
The main objective of pharmacologic treatment of hypertension is to attain and maintain the goal blood pressure. Lifestyle interventions should be maintained throughout treatment (Table 1). Medications can be initiated and titrated according to any of three strategies used in the randomized controlled trials selected by the panel (detailed below). Do not use an ACE inhibitor and ARB together in same patient.
If blood pressure is not at goal using all medication classes as in Recommendation 6 (ie, the triple combination of a thiazide-type diuretic, calcium channel blocker, and either an ACE inhibitor or an ARB), if there is a contraindication to any of these medication classes, or if there is need to use more than three medications to reach the goal, drugs from other classes can be used.
Referral to a hypertension specialist may be indicated for patients who are not at goal using the above strategy or for whom additional clinical consultation is needed.
Strength of recommendation—expert opinion (grade E).
Comments. Blood pressure should be monitored and assessed regularly, treatment adjusted as needed, and lifestyle modifications encouraged.
The panel did not recommend any monitoring schedule before or after goal blood pressure is achieved, and this should be individualized.
