Treatment of severe hypertension with atenolol and betaxolol with once-daily regimens. Hemodynamic aspects

Current and future status of beta-blockers in the treatment of hypertension

Beta-adrenergic receptor blockers (beta-blockers) are effective and safe antihypertensive drugs, and have been recommended as first-line therapy for hypertension by all Joint National Committees (JNCs) for the prevention, detection, evaluation, and treatment of high blood pressure (BP) from the first to the last (JNC-7) in 2003. However, recently questions have been raised by several investigators regarding the antihypertensive effectiveness and safety of these drugs. The Medline literature on this subject was searched and pertinent studies were retrieved. Other pertinent references from existing publications were retrieved and analyzed up to 2007. Additionally, a historical perspective on the discovery of beta-blockers and their mechanism of action is given. Most of the reviewed short-term and long-term clinical trials demonstrate an effective and safe antihypertensive pattern for the beta-blockers. The weaknesses identified include the adverse effect of older beta-blockers on glucose control and stroke protection, especially in older persons. These adverse effects are attributed to their mechanism of action and BP effectiveness. On the basis of the evidence presented, beta-blockers are effective and safe antihypertensive drugs and should still be recommended as first-line therapy in most uncomplicated hypertensive patients, either alone or in combination with other drugs. There are reservations regarding their administration to diabetic and older hypertensive patients. However, when compelling indications for their use exist, they should not be withheld.

Antihypertensive effectiveness of a very low fixed-dose combination of moexipril and hydrochlorothiazide

The antihypertensive and metabolic effects of a fixed combination of very low dose of moexipril (MO), an angiotensin-converting enzyme (ACE) inhibitor, and hydrochlorothiazide (HCTZ) were tested in a multicenter, placebo (PBO) controlled, double-blind, parallel study of men (M) and women (W) with mild to moderate essential hypertension. After 4 weeks of PBO treatment, 223 patients with sitting diastolic blood pressure (SDBP) of 95-114 mm Hg and sitting systolic blood pressure (SSBP) < or =200 mm Hg, inclusive, were randomized to PBO (114 patients: M, 56; W, 58) and MO/HCTZ 3.75/6.25 mg (109 patients: M, 58; W, 51) given once daily and followed up for 12 weeks. The fixed combination MO/HCTZ, 3.75/6.25 mg, reduced SSBP/SDBP -7.6/-7.6 mm Hg (M, -8.5/-8.0; W, -6.3/-7.0), versus PBO, +0.2/-3.9 mm Hg (M, -1.9/-3.4; W, +1.1/-4.4); p < 0.05. Also, 54% of patients receiving MO/HCTZ, 3.75/6.25 mg/day, had good blood pressure response (SDBP < or =90 mm Hg, or > or =10 mm Hg decrease from baseline), versus 28% for PBO (p < 0.001). The clinical and metabolic side effects were minor and not different between MO/HCTZ and PBO. The results of this study indicate (a) a once-daily very low dose fixed combination of MO/HCTZ is effective and well tolerated by men and women with mild to moderate essential hypertension; (b) it is almost devoid of clinical and metabolic side effects; and (c) the safety profile was similar in men and women.

Clinical utility of long-term enalapril/diltiazem ER in stage 3-4 essential hypertension. Long-term Use of Enalapril/Diltiazem ER in Stage 3-4 Hypertension Group

The use of angiotensin converting enzyme inhibitors and calcium channel blockers, as monotherapies and in combination, is common in the management of hypertension. Clinical studies have documented the augmentation of blood pressure reduction when these agents are combined compared with the individual agents, in short-term studies. In the present investigation, 93 patients with stage 3-4 essential hypertension, who successfully completed a short-term double-blind study, participated in a 40-week open-label treatment phase. The patients were maintained on their previous doses of enalapril/diltiazem ER (E/D) with or without additional antihypertensive medications. Doses of medication could be adjusted as necessary for blood pressure control. Of the 93 patients, 68% were male and 82% were white; they averaged 52.7 years of age and had a baseline mean sitting blood pressure (SiBP) of 167/111 mmHg. The use of E/D alone (n = 14) reduced mean SiBP by 14.5/14.4 mmHg from baseline, whereas the use of E/ D with other agents (n = 79) decreased it by 27/20.5 mmHg from baseline. E/D alone or in combination with other drugs was well-tolerated, and no serious adverse events were noted. This long-term open-label study demonstrated that the E/D combination alone or with the addition of other antihypertensive drugs was effective, safe, and well-tolerated after prolonged administration.

Sustained blood pressure control with controlled-release isradipine (isradipine-CR)

The safety and efficacy, as measured by peak/trough blood pressure reduction, of a new, once-daily, controlled-release formulation of isradipine (isradipine-CR, ICR) were evaluated in patients with mild to moderate essential hypertension during a nine-week trial. After a 3-week placebo washout period, patients with a sitting diastolic blood pressure between 100 and 114 mm Hg were randomized to either 1 of 4 ICR treatment groups or placebo. Of 402 randomized patients, 384 completed the study (placebo = 77, ICR-5 mg = 76, ICR 10 mg = 76, ICR-15 mg = 78, and ICR-20 mg = 77). Peak and trough post-dose blood pressure responses and heart rates were monitored for both the sitting and upright positions. Blood chemistries, urinalyses, complete blood counts, and electrocardiograms were done during the study. Both sitting and upright blood pressure decreased with the 5-(P < .05), 10-, 15-, and 20-mg (P < .001) once-daily ICR doses. The peak blood pressure reduction for all ICR doses occurred at 8 to 10 hours post-dose. Maximum peak/trough blood pressure response, achieved with the 10-mg dose, was similar with that of 15 and 20 mg of ICR. No serious clinical or metabolic side effect were noted, except ankle edema, which was dose dependent but did not require discontinuation of treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of atenolol and diltiazem-SR on exercise and pressure load in hypertensive patients

The effects of monotherapy with atenolol or diltiazem-SR on blood pressure, 24-h blood pressure (BP) load, and exercise capacity were tested in patients with mild to moderate (stages I and II) essential hypertension. After 3-week single-blind placebo therapy, patients with sitting diastolic blood pressure (SDBP) of 94-114 mmHg were randomized to atenolol 50 mg/day (62 patients) or diltiazem-SR 90 mg b.i.d. (60 patients) in a double-blind parallel study. Depending on SDBP response, the dose was increased to 100 mg/day for atenolol and 180 mg b.i.d. for diltiazem-SR. Twenty-four-hour ambulatory blood pressure measurements and exercise tolerance test by the Bruce protocol were done at the end of placebo and active treatment. Compared with placebo, both atenolol and diltiazem-SR significantly decreased heart rate (HR), sitting systolic blood pressure (SSBP), SDBP, ambulatory BP, BP load for waking and sleeping hours, area under the BP curve, rate-pressure product (p < 0.001), and exercise time (NS). Atenolol exerted a greater effect on ambulatory BP, HR, rate-pressure product, waking diastolic BP load, and area under the 24-h BP curve. The drugs were well tolerated and caused no serious side effects necessitating discontinuation of treatment. These findings indicate that (1) monotherapy for hypertension with atenolol or diltiazem-SR is effective and well tolerated, (2) it decreases the 24-h BP load, (3) it does not interfere with exercise capacity.

Antihypertensive and metabolic effects of single and combined atenolol regimens

The antihypertensive and metabolic effects of placebo (PL), a fixed combination of hydrochlorothiazide (25 mg) and triamterene (50 mg) (HCTZ/TRI), atenolol (25 mg) (Atc-25), atenolol (50 mg) (Ate-50) and their combination with HCTZ/TRI given once daily, were tested on 256 patients with mild-to-moderate essential-hypertension. After 3 weeks of PL monotherapy, 43 patients were randomized to PL (group 1), 41 patients to HCTZ/TRI (group 2), 44 patients to Ate-25 (group 3), 42 patients to Ate-50 (group 4), 43 patients to Ate-25/HCTZ/TRI (group 5), and 43 patients to Ate-50/HCTZ/TRI (group 6) in a double-blind parallel design study and were followed for 4 weeks. At the end of week 7, those patients who were randomized to groups 5 and 6 were allowed to continue for an additional 12 weeks, if their arterial pressure was satisfactorily controlled. Complete blood counts, blood chemistries, urinalyses, and electrocardiograms were done initially and during the study. Monotherapy with HCTZ/TRI, Ate-25, and Ate-50 had significant and equal antihypertensive effects compared with placebo. (P less than .01). However, the combination of Ate-25/HCTZ/TRI and Ate-50/HCTZ/TRI resulted in further reduction of arterial pressure with the effect being greatest with Ate-50/HCTZ/TRI (P less than .001). Patient groups 3 through 6 had also slower heart rates compared with groups 1 and 2 (P less than .01). Mild, but statistically significant, increases in BUN, glucose, triglycerides, and uric acid were noted in groups 2, 5, and 6 (P less than .05).(ABSTRACT TRUNCATED AT 250 WORDS)