DIURETICS, BETA-BLOCKERS ARE FIRST-LINE DRUG THERAPY FOR HYPERTENSION

DIURETICS, BETA-BLOCKERS ARE FIRST-LINE DRUG THERAPY FOR HYPERTENSION, a report from the National High Blood Pressure Education Program's (NHBPEP) coordinating committee concludes. Issued Oct. 30, the report is the fifth on the subject of hypertension released by the Joint National Committee on the Detection, Evaluation and Treatment of High Blood Pressure, or JNC V, and is intended as a treatment guideline for health care professionals. The report is an update of JNC IV, published in 1988 ("The Pink Sheet" Feb. 1, 1988, p. 12). JNC V emphasizes lifestyle modifications as the first-choice intervention, focusing on weight reduction, moderation of alcohol intake, regular physical activity, reduction of sodium intake and smoking cessation. If the patient shows an inadequate response, the guidelines recommend drug monotherapy for stage one and two (mild to moderate) hypertension. "Because diuretics and beta- blockers have been shown to reduce cardiovascular morbidity and mortality in controlled clinical trials, these two classes of drugs are preferred for initial drug therapy," the report states. A meta-analysis of 14 randomized trials by the NHBPEP "has indicated a 42% reduction in stroke from a 5 to 6 mm Hg lowering of DBP [diastolic blood pressure]." However, NHBPEP notes, the same meta-analysis showed a lesser reduction in coronary heart disease (CHD), "14% over periods of four to six years." The meta- analysis did not include data from the Systolic Hypertension in the Elderly Program (SHEP), the Swedish Trial in Old Patients with Hypertension (STOP-Hypertension) and the Medical Research Council (MRC), which demonstrated 27%, 13% and 19% reduction of CHD events, respectively, the report notes. ACE inhibitors and calcium antagonists are cited as useful second-line treatments, whereas the 1988 report included the two in the first-line category. Other second-line treatments include alpha[1] -receptor blockers and an alpha-beta blocker. These classes of antihypertensives "are equally effective in reducing blood pressure" and "have potentially important benefits," the report notes. However, NHBPEP recommends a return to second-line status for ACEs and calcium channel blockers because they "have not been used in long-term controlled trails to demonstrate their efficacy in reducing morbidity and mortality and therefore should be reserved for special indications or when diuretics and beta-blockers have proved unacceptable or ineffective. There is an urgent need" to study their effectiveness in doing so, the JNC V concludes. If the patient shows inadequate response after treatment, the guidelines recommend increasing the drug dosage, substituting another drug, or adding a second agent from a different class. If no progress is achieved, a second or third agent and/or a diuretic may be added, if one is not already prescribed. The guidelines apply to stages three and four hypertensive patients as well; however, an expedited treatment schedule or increased dosages of some drugs may be necessary. Special considerations to be taken into account when selecting an initial drug therapy are demographic characteristics, concomitant diseases and the use of other drugs by the patient, the report notes. For example, African-Americans "in general... are more responsive to diuretics and calcium antagonists" than to beta-blockers and ACEs, while older persons are "generally responsive to all classes of drugs," the report states. Beta- blockers may worsen asthma, diabetes and peripheral ischemia but may improve angina, certain dysrhythmias and have been shown to prolong life after MI. The potential for sexual function impairment, assessments by physiologic and biochemical measurements and pricing barriers are other factors that health care professionals must take into consideration, the report suggests. The NHBPEP was created in 1972 as a cooperative effort between the National Heart, Lung and Blood Institute and professional and voluntary health agencies. The program is similar in design to the institute's National Cholesterol Education Program, begun in 1985 to educate health care professionals and the public about the role of cholesterol in coronary heart disease. Both programs involve periodic evaluation of interventions and publication of updated treatment guidelines. A national campaign to increase primary prevention of hypertension is recommended in a same-day report released by the NHBPEP. NHLBI would oversee the effort, in consultation with the 43 professional and voluntary organizations represented on the coordinating committee. The "Working Group Report on Primary Prevention of Hypertension" recommends a two-pronged approach to lowering blood pressure levels. First, a "population strategy" would apply blood pressure-lowering interventions to the general population "with the objective of achieving a downward shift in the entire distribution of blood pressure." The second approach, a "targeted strategy," would involve attempting to lower blood pressure "among those who are most likely to develop hypertension." The panel calls for additional research to be conducted on primary prevention of hypertension, including preventing unhealthy lifestyles in childhood and adolescence; preventing hypertension in minority populations who have "a disproportionately large burden of illness from hypertension;" avoidance of recidivism; and the role of nutrient supplementation in population subgroups. Clinical trials of longer duration are also recommended, and the working group cites research into developing strategies to incorporate prevention activities into primary care practice as a "high priority."