P&T News: Winter/Spring 2004
Adapted from JNC 7
Peer Review Status: Internally Peer
Reviewed
The "Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure" provides a new guideline for hypertension prevention and management1. Key points include:
Benefits of Lowering Blood Pressure
In clinical trials, antihypertensive therapy has been associated with reductions in stroke incidence averaging 35-40%, myocardial infarction, 20-25% and heart failure, more than 50%. It is estimated that in patients with stage 1 hypertension (SBP 140-159 mmHg and/or DPB 90-99 mmHg) and additional cardiovascular risk factors, achieving a sustained 12 mmHg reduction in SBP over 10 years will prevent 1 death for every 11 patients treated. In the presence of CVD or target organ damage, only 9 patients would require such BP reduction to prevent a death.
Treatment Guidelines
Lifestyle Modifications
Adoption of healthy lifestyles by all persons is critical for the
prevention of high BP and is an indispensable part of the management
of those with hypertension. Major lifestyle modifications shown to
lower BP include weight reduction in those individuals who are
overweight or obese, adoption of the Dietary Approaches to Stop
Hypertension (DASH) eating plan which is rich in potassium and
calcium, dietary sodium reduction, physical activity, and moderation
of alcohol consumption. Lifestyle modifications reduce BP, enhance
antihypertensive drug efficacy, and decrease cardiovascular risk. For
example, a 1,600 mg sodium DASH eating plan has effects similar to
single drug therapy. Combinations of two (or more) lifestyle
modifications can achieve even better results.
Pharmacologic Treatment
Thiazide-type diuretics have been the basis of antihypertensive
therapy in most outcome trials. In these trials, diuretics have been
virtually unsurpassed in preventing the cardiovascular complications
of hypertension. Diuretics enhance the antihypertensive efficacy of
multidrug regimens, can be useful in achieving BP control, and are
more affordable than other antihypertensive agents. Despite these
finding, diuretics remain underutilized.
Thiazide-type diuretics should be used as initial therapy for most patients with hypertension, either alone or in combination with one of the other classes demonstrated to be beneficial in randomized controlled outcome trials. The list of compelling indications requiring the use of other antihypertensive drugs as initial therapy is shown in Table 1. If a drug is not tolerated or is contraindicated, then one of the other classes proven to reduce cardiovascular events should be used instead.
Achieving Blood Pressure Control in Individual Patients
Most patients who are hypertensive will require two or more
antihypertensive medications to achieve the BP goals. Addition of a
second drug from a different class should be initiated when use of a
single drug in adequate doses fails to achieve the BP goal. When BP
is more than 20/10 mmHG above goal, consideration should be given to
initiating therapy with two drugs, either as separate prescriptions
or in fixed-dose combinations. (See Figure 1.)
The initiation of drug therapy with more than one agent may increase
the likelihood of achieving the BP goal in a more timely fashion, but
particular caution is advised in those at risk for orthostatic
hypotension, such as patients with diabetes, autonomic dysfunction,
and some older persons. Use of generic drugs should be considered to
reduce prescription costs.
Followup and Monitoring
Once antihypertensive drug therapy is initiated, most patients
should return for followup and adjustment of medications at
approximately monthly intervals until the BP goal is reached. More
frequent visits will be necessary for patients with stage 2
hypertension or with complicating comorbid conditions. Serum
potassium and creatinine should be monitored at least 1-2 times per
year. After BP is at goal and stable, followup visits can usually be
at 3- to 6-month intervals. Comorbidities, such as heart failure,
associated diseases such as diabetes, and the need for laboratory
tests influence the frequency of visits. Other cardiovascular risk
factors should be treated to their respective goals, and tobacco
avoidance should be promoted vigorously. Low-dose aspirin therapy
should be considered only when BP is controlled, because the risk of
hemorrhagic stroke is increased in patients with uncontrolled
hypertension.
Improving Hypertension Control
Adherence to Regimens
Behavioral models suggest that the most effective therapy
prescribed by the most careful clinician will control hypertension
only if the patient is motivated to take the prescribed medication
and to establish and maintain a health-promoting lifestyle. Patient
attitudes are greatly influenced by cultural differences, beliefs,
and previous experiences with the health care system. Failure to
titrate or combine medications, despite knowing the patient is not at
goal BP, represents clinical inertia and must be overcome. The
clinician and the patient must agree upon BP goals. Patients'
nonadherence to therapy is increased by misunderstanding of the
condition of treatment, denial of illness because of lack of symptoms
or perception of drugs as symbols of ill health, lack of patient
involvement in the care plan, or unexpected adverse effects of
medications. The patient should be made to feel comfortable in
telling the clinician all concerns and fears of unexpected or
disturbing drug reactions. The cost of medications and the complexity
of care are additional barriers that must be overcome to achieve goal
BP. All members of the health care team must work together to
influence and reinforce instructions to improve patients' lifestyles
and BP control.
Figure 1. Algorithm for Treatment of Hypertension
Resistant Hypertension
Resistant hypertension is the failure to reach goal BP in
patients who are adhering to full doses of an appropriate three-drug
regimen that includes a diuretic. After excluding potential
identifiable hypertension, clinicians should carefully explore
reasons why the patient is not at goal BP. (See Table
2.)
Summary
This article has summarized the JNC 7 treatment guidelines. Thiazide diuretics are inexpensive and should be used as initial treatment for most patients with hypertension. The complete guidelines can be found at http://www.nhlbi.nih.gov. A pocketcard that summarizes these guidelines is also available; call the Drug Information Center if you would like to receive a copy.
Reference:
1 Adapted from The Seventh Report of the Joint
National Committee on Prevention, Detection, and Treatment of High
Blood Pressure. http://www.nhlbi.nih.gov
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Table 1. Clinical Trial and Guideline Basis for Compelling Indications for Individual Drug Classes |
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COMPELLING |
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Heart Failure |
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Postmyocardial infarction |
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High coronary disease risk |
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Diabetes |
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Chronic kidney disease |
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Recurrent stroke prevention |
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X Compelling indications for antihypertensive drugs are based on benefits from outcome or existing clinical guidelines; the compelling indication is managed in parallel with the BP. # Drug abbreviations: ACEI, angiotensin converting enzyme inhibitor; ARB, angiotensin receptor blocker; Aldo ANT, aldosterone antagonist; BB, beta-blocker; CCB, calcium channel blocker. |
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Table 2. Causes of Resistant Hypertension |
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Improper BP Measurement |
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Volume Overload and Pseudotolerance
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Drug-Induced or Other Causes
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Associated Conditions
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Look for "Adverse Drug Reaction (NOT Med Error)" under IPR's Incident Reporting Tab.
Beginning in March 2004, the UIHC Adverse Drug Reaction (ADR) Reporting Program will begin receiving ADR reports via IPR which is currently utilized by staff to report and document other types of patient adverse incidents. The Adverse Drug Reaction Reporting Program (administered under the auspices of the Pharmacy and Therapeutics Subcommittee and coordinated by the Department of Pharmaceutical Care) monitors adverse drug reactions that affect our patients. The World Health Organization has defined an adverse drug reaction as "any response to a drug which is noxious and unintended, and which occurs at doses normally used in man for the prophylaxis, diagnosis, or therapy of disease, or for the modification of physiological function." (Please note that adverse drug reactions are distinct from medication errors; each occurrence is defined below.)
ADR reports involve a wide variety of medications, including agents that are new to the market as well as older, well-established products. All health care professionals must perform vigilant post-marketing surveillance in order to continue necessary monitoring after new agents reach the market. New data are used to update the prescribing information of recently approved agents and, in some cases, drug entities that have been marketed for years. The data may also lead to the market withdrawal of products associated with adverse reactions that were previously unrecognized or occur frequently with widespread use. We have all heard or seen information about adverse drug reactions that have occurred in the course of patient care within the hospital; unfortunately, many of these occurrences are never documented or reported by staff who are most familiar with the patient and the adverse event.
Whenever you become aware of an adverse drug reaction (whether in the inpatient or ambulatory care environments), please complete and submit an adverse drug reaction incident report using IPR. The yellow adverse drug reaction reporting cards formerly located on patient care units and ambulatory care clinics will no longer be available for this purpose.
If you have questions about whether an adverse event should be reported as an adverse drug reaction, please feel free to contact Kevin Bebout, Administrative Pharmacy Practice Specialist, or contact the Drug Information Center.
Thank you for your support of this important patient safety program.
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