The New Hypertension Guidelines
Address for correspondence: Ralph Stern, PhD, MD, Department of Internal Medicine, Division of Cardiovascular Medicine, University of Michigan, 24 Frank Lloyd Wright Drive, Ann Arbor, MI 48106
The Canadian Hypertension Education Program (CHEP) has published guidelines annually since 2000. The CHEP guidelines are a model of concise, comprehensive, up-to-date, evidence-rated guidelines for physicians who diagnose and treat hypertension. The guidelines address measurement of blood pressure and the definition of hypertension, secondary hypertension evaluation and treatment, and blood pressure targets and medication choices in patients with and without compelling indications. This review describes CHEP's process for developing guidelines and provides an overview of the 2013 recommendations.
The National High Blood Pressure Education Program celebrated its 40th anniversary in 2012. The Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC) published guidelines in 1976, 1980, 1984, 1988, 1992, 1997, and 2003 and new guidelines are anticipated in 2013. Moser and Rocella described the US guidelines as “the national and international standard.” Other regions and countries have developed guidelines, and comparing their approach to the diagnosis and management of hypertension is informative. The Canadian Hypertension Education Program (CHEP) has published guidelines annually since 2000. This review describes CHEP's process for developing guidelines and provides an overview of the 2013 recommendations.
Each year a literature review is performed and this year the results were provided to a recommendations task force with two co-chairs and 23 subgroups. Each subgroup revised and/or generated recommendations and these changes were then reviewed, graded, and refined by an independent central review committee of methodology experts with no industry affiliations. The new recommendations were then presented at a 1-day consensus conference with the participation of other organizations. The recommendations were then voted on by the recommendations task force and those with support by 70% of the votes were included.
The revised guidelines were then made available on www.hypertension.ca in a collection of documents and presentations. The guidelines were subsequently published in the Canadian Journal of Cardiology.
The format has evolved over the years. For example, in the past, blood pressure (BP) measurement, diagnosis, and assessment of risk were covered in a separate publication from therapy. In the past, supplementary tables were not utilized. Each year's guidelines specify the changes from the preceding guidelines. For 2013, these were changing the systolic BP (SBP) threshold for drug treatment in the very elderly (older than 80 years) to 150 mm Hg and specifying that resistance or weight training for nonhypertensive or stage 1 hypertensive individuals does not adversely influence BP. For 2012, these were using home BP monitoring to confirm a diagnosis of white-coat hypertension, use of mineralocorticoid receptor antagonists for hypertension with systolic heart failure, not choosing an angiotensin blocker based on a history of atrial fibrillation, and changing the BP target for patients with nondiabetic chronic kidney disease (CKD) to <140/90 mm Hg. For 2011, these were using comparative risk analogies when discussing cardiovascular risk, discussing diagnostic testing issues for renal artery stenosis, adding advice on BP management acutely in stroke, considering patients with hypertension and diabetes at high risk if they have other risk factors, preferring the combination of an angiotensin-converting enzyme (ACE) inhibitor with a dihydropyridine calcium channel blocker over the combination of an ACE inhibitor and a thiazide diuretic in patients with hypertension and diabetes, and recommending coordination with pharmacists to improve adherence. For 2010, these were adding automated office BP measurements, revising the dietary sodium targets, advising an ACE inhibitor or angiotensin receptor blocker (ARB) in patients with hypertension and ischemic heart disease, and preferring a calcium channel blocker/ACE inhibitor combination in high-risk patients.[5, 6]
The core guidance is presented in the text and summarized in an extensive table providing BP targets and choice of initial therapy for patients with and without compelling indications, along with annotations.
In addition to the core guidance summarized below, supplementary tables provide additional information on the grading scheme used for recommendations; the recommended technique for measuring office BP; hypertensive urgencies and emergencies; target organ damage; cardiovascular risk factors for atherosclerosis; exogenous substances that produce hypertension; screening, diagnosis, and treatment of hyperaldosteronism; screening, diagnosis, and treatment of pheochromocytoma; the Dietary Approaches to Stop Hypertension (DASH) diet; possible reasons for poor response to treatment; cardiovascular risk factors for consideration of statin therapy; and strategies to improve patient adherence.
Measurement of BP
CHEP recommends that manual office BPs, automated office BPs, home BPs, and ambulatory BPs can be used.
Definition of Hypertension
With a first visit manual office BP reading, a patient is considered hypertensive if they have a hypertensive urgency or emergency. At a second visit, a patient is considered hypertensive if BP is >180/110 mm Hg or BP >140/90 mm Hg with macrovascular target organ damage, diabetes mellitus (DM), or CKD. If the average BP is >160/100 mm Hg across 3 visits or >140/90 mm Hg across 5 visits, the patient is also considered hypertensive. Hypertensive urgencies and emergencies included diastolic BP (DBP) ≥130 mm Hg as well as severe BP elevations with hypertensive encephalopathy, acute aortic dissection, acute left ventricular failure, acute coronary syndrome, acute kidney injury, intracranial hemorrhage, acute ischemic stroke, and eclampsia of pregnancy. Examples of target organ damage include cerebrovascular disease, hypertensive retinopathy, left ventricular dysfunction, coronary artery disease, renal disease, and peripheral artery disease.
The BP criterion for considering a patient hypertensive is >135/85 mm Hg for automated office BP readings, home BP readings, and daytime ambulatory BP readings, or >130/80 mm Hg for 24-hour ambulatory BP readings.
Global Cardiovascular Risk Assessment
Assessment was advised with patients informed using analogies (eg, cardiovascular age) rather than absolute risk levels.
Initial Laboratory Evaluation
Sodium, potassium, creatinine, urinalysis, fasting blood sugar, and lipid measurement and electrocardiography are suggested, with measurement of urinary albumin in patients with diabetes.
Screening for Renovascular Hypertension
Further evaluation is advised if ≥2 of the following are present: sudden onset or worsening of hypertension in patients younger than 30 or older than 55 years, abdominal bruit, resistance to ≥3 drugs, >30% rise in creatinine with an ACE inhibitor or ARB, atherosclerotic vascular disease, and recurrent pulmonary edema with hypertensive surges.
Screening for Hyperaldosteronism
Screening should be considered if spontaneous hypokalemia (K<3.5), marked diuretic-induced hypokalemia (<3.0), hypertension refractory to ≥3 drugs, or an adrenal adenoma are present. Screening with an aldosterone/plasma renin ratio is advised with a cutoff for a positive test of 26.8 (converted from SI units). A confirmatory test is required after a positive screening test.
Screening for Pheochromocytoma
Screening should be considered for paroxysmal and/or severe (>180/100 mm Hg) sustained hypertension refractory to usual treatment; hypertension with multiple suggestive symptoms; hypertension triggered by drugs, micturition, or changes in abdominal pressure; an adrenal mass; or hypertension with multiple endocrine neoplasia 2A or B, neurofibromatosis, or von Hippel–Lindau syndrome. Localization with magnetic resonance imaging is preferred over computed tomography or MIBG.
Use of Home BP Monitoring
Home BP readings can be used for the management of hypertension, especially in patients with DM, CKD, suspected nonadherence, white-coat effect, and masked hypertension. A repeat set of home BP readings can be used to confirm a diagnosis of white-coat hypertension as an alternative to ambulatory BP monitoring. Validated machines should be used, with a preference for devices that record and/or transmit the readings. Duplicate measures in the morning and evening for 7 days, with the first day's readings discarded, are recommended.
Use of Ambulatory BP Monitoring
Ambulatory BP monitoring with validated machines can be used for the management of hypertension. It should be considered for patients not at target taking appropriate therapy, in the presence of symptoms suggesting hypotension, and with fluctuating office BP readings. Either a daytime mean >135/85 mm Hg or a 24-hour mean >130/80 mm Hg can be used as criteria to adjust medications. The nocturnal BP drop should be considered when using ambulatory BP data.
Use of Echocardiography
Echocardiography is not routinely recommended but can be useful for the diagnosis of left ventricular hypertrophy in select cases. It is indicated for suspected left ventricular dysfunction or coronary artery disease.
Guidance is provided on physical exercise, weight reduction, alcohol consumption, dietary recommendations, sodium intake, and stress management. Increasing potassium, calcium, and magnesium intake are not advised.
Indications for Drug Therapy in Patients Without Compelling Indications
Medications should be prescribed for patients with BP >160/100 mm Hg without target organ damage or other cardiovascular risk factors. Medications should be strongly considered for patients with BP >140/90 mm Hg if there is macrovascular target organ damage or other cardiovascular risk factors. These recommendations apply regardless of the age of the patient.
Choice of Therapy for Combined Systolic/Diastolic or Isolated Diastolic Hypertension in Patients Without Compelling Indications
Initial therapy can be with a thiazide diuretic, a β-blocker (in those younger than 60 years), an ACE inhibitor (in nonblack patients), a calcium channel blocker, or an ARB. If a second agent is needed, the same medications can be considered, but preference is given to choice of an agent from a different group (group 1: diuretic and calcium channel blocker; group 2: ACE inhibitor, ARB, and β-blocker). If the initial SBP/DBP is >20/10 mm Hg above target, two drugs can be started simultaneously. A third drug can be added if needed, but reasons for poor response should be considered. α-Blockers as initial drug therapy should be avoided.
Choice of Therapy for Isolated Systolic Hypertension in Patients Without Compelling Indications
The target for SBP in the very elderly is <150 mm Hg. Initial therapy can be with a thiazide diuretic, a dihydropyridine calcium channel blocker, or an ARB. If a second agent is needed, the same medications can be considered. If a third drug is needed, other classes of drugs can be considered. Reasons for poor response should be considered. α-Blockers or β-blockers in those older than 60 years as initial therapy should be avoided.
Reduction of Global Cardiovascular Risk in Patients Without Compelling Indications
Statins are recommended in patients with ≥3 cardiovascular risk factors (other than hypertension) or established atherosclerotic disease. These include male sex, age older than 55, left ventricular hypertrophy, other electrocardiographic abnormalities, peripheral arterial disease, stroke or transient ischemic attack, microalbuminuria or proteinuria, DM, smoking, positive family history of premature cardiovascular disease, or total/high-densitylipoprotein cholesterol ratio >6. Low-dose aspirin should be strongly considered. However, a review of this issue is planned for 2014, based on a 2011 Cochrane review that concluded the decrease in myocardial infarctions with antiplatelet therapy was matched by an increase in major bleeding in patients with hypertension without a history of stroke or myocardial infarction.
BP Target in Patients Without Compelling Indications
The BP goal in patients without compelling indications is <140/90 mm Hg.
Treatment of Hypertension in Patients With Coronary Artery Disease
ACE inhibitors or ARBs are recommended, except with angina where a β-blocker (or a calcium channel blocker) is preferred as initial therapy. Short-acting nifedipine should not be used. Without systolic heart failure, an ACE inhibitor should not be combined with an ARB in patients with coronary artery disease. Combinations of an ACE inhibitor and a dihydropyridine calcium channel blocker are preferred to combinations of an ACE inhibitor and a diuretic.
Treatment of Hypertension in Patients With Myocardial Infarction
For initial therapy, β-blockers and ACE inhibitors (or ARBs) should both be used. A calcium channel blocker can be considered if a β-blocker is contraindicated or not effective, but nondihydropyridine calcium channel blockers should be avoided if heart failure is present. CHEP reviewed the J curve and did not propose a DBP threshold, but will follow this issue.
Treatment of Hypertension in Patients With Heart Failure
Initial therapy with an ACE inhibitor (or ARB) or a β-blocker is preferred. Aldosterone antagonists can be added in select patients with careful monitoring for hyperkalemia in the presence of an ACE inhibitor or ARB. Diuretics can also be added. The combination of hydralazine and isosorbide dinitrate can be used if an ACE inhibitor or ARB is not used, but the combination of an ACE inhibitor and an ARB requires careful monitoring. Dihydropyridine calcium channel blockers can also be used.
Treatment of Hypertension in Patients With Stroke
Acute (within the first 72 hours) therapy is not routinely advised in a patient not eligible for thrombolysis; however, a 15% to 25% reduction over 24 hours is reasonable when BP exceeds 220/120 mm Hg. Treatment should also be given to a patient eligible for thrombolysis with BP >185/110 mm Hg. After the acute phase, the BP target is <140/90 mm Hg with an ACE inhibitor and/or diuretic. Combination of an ACE inhibitor and an ARB is not recommended.
Treatment of Hypertension in Patients With Left Ventricular Hypertrophy
An ACE inhibitor, ARB, calcium channel blocker, or thiazide diuretic can be used for initial drug therapy. However, vasodilators should not be used.
Treatment of Hypertension in Patients With Nondiabetic CKD
The BP target is <140/90 mm Hg. Initial therapy with an ACE inhibitor (or ARB) is preferred with proteinuria. A thiazide diuretic can be considered as additional therapy, with loop diuretics preferred with volume overload. Combination therapy may be needed, but the combination of an ACE inhibitor and an ARB is not recommended for nonproteinuric CKD.
Treatment of Hypertension in Patients With Renovascular Disease
No specific drugs are indicated,but caution should be exercised with ACE inhibitors or ARBs. Early intervention with stents or surgery could be considered in patients with hypertension uncontrolled by ≥3 drugs, deteriorating kidney function, bilateral atherosclerotic renal artery lesions, or recurrent episodes of flash pulmonary edema.
Treatment of Hypertension in Patients With DM
The BP target in patients with DM is <130/80 mm Hg. Initial combination therapy should be considered if SBP/DBP is >20/10 mm Hg above target. An ACE inhibitor or ARB is preferred in the presence of cardiovascular disease or CKD (including microalbuminuria). Otherwise, initial drug choices include an ACE inhibitor, an ARB, a dihydropyridine calcium channel blocker, or a thiazide diuretic. When combining medications, a dihydropyridine calcium channel blocker and an ACE inhibitor is preferred over a diuretic and an ACE inhibitor.
CHEP provides a model of concise, comprehensive, up-to-date, evidence-rated guidelines for physicians who diagnose and treat hypertension. The most striking differences from the JNC 7 recommendations are the conservative approach to the treatment of stage I hypertension, separate BP targets for patients with diabetes (<130/80 mm Hg) and with nondiabetic CKD (<140/90 mm Hg), and not necessarily favoring diuretics above all other choices as initial therapy in patients without compelling indications. It will be interesting to compare these 2013 guidelines with the JNC 8 recommendations and see whether they have converged or diverged. Since CHEP has developed guidelines annually since 2000, US hypertension specialists may wish to follow future CHEP recommendations, especially if there is a long hiatus between JNC 8 and JNC 9.
Statement of financial disclosure
The author reports no specific funding in relation to this paper and no conflicts of interest to disclose.