Amlodipine versus atenolol in essential hypertension

The efficacy and safety of amlodipine (2.5–10 mg) once daily was compared with atenolol (50–100 mg) once daily in patients with mild-to-moderate essential hypertension in a randomized, doubleblind, parallel, placebo-controlled study. A total of 125 patients were randomly allocated at the end of a 4-week run-in placebo period to 8 weeks of double-blind treatment with amlodipine (n = 41), atenolol (n = 43), or placebo (n = 41). The placebo group had small mean changes in supine and standing blood pressure compared with baseline. The mean blood pressure changes from baseline 24 hours postdose in the amlodipine group (mean daily dose 8.8 mg) were −12.8/−10.1 mm Hg for supine blood pressure and −11.5/−9.8 mm Hg for standing blood pressure (p < 0.001 compared with placebo), and for the atenolol group (mean daily dose 83.7 mg) the changes were −11.3/−11.7 mm Hg for supine blood pressure and −13.3/−12.3 mm Hg for standing blood pressure (p < 0.001 compared with placebo). There were no statistically significant blood pressure differences between active treatments. The responder rates for amlodipine, atenolol, and placebo were 61.1, 64.9, and 11.1%, respectively. The blood pressure values taken over the 24-hour period at final visit revealed that amlodipine and atenolol maintained the supine blood pressure ≤ 140/90 mm Hg throughout the period of observation; the corresponding time-effect curve for the placebo group was clearly in the hypertensive range. Heart rate was significantly lowered by atenolol only. Both amlodipine and atenolol were well tolerated. Only 1 patient was withdrawn due to adverse effects (development of peripheral edema, arthralgia and fatigue) related to amlodipine. This study demonstrates that once-daily therapy with amlodipine or atenolol was well tolerated in patients with mild-to-moderate essential hypertension and provided control of blood pressure throughout the 24-hour dosing interval.     

Amlodipine lowers blood pressure without affecting cerebral blood flow as measured by single photon emission computed tomography in elderly hypertensive subjects.

AIM: To evaluate the effect of amlodipine on blood pressure and cerebral blood flow in elderly subjects with mild to moderate hypertension. METHODS: A double-blind, parallel group study of 26 patients. After a 4-week placebo run-in period, amlodipine (5-10 mg) or matching placebo was given once daily for 8 weeks. RESULTS: Amlodipine significantly reduced blood pressure compared with baseline. Diastolic blood pressure was significantly reduced by amlodipine compared with placebo (P< 0.02 to P< 0.01). Ambulatory blood pressure monitoring showed that blood pressure control was sustained over the 24-h dosing interval. Relative regional cerebral blood flow, assessed using single photon emission computed tomography, was not significantly affected by amlodipine. Three placebo patients, but no amlodipine patients, withdrew because of adverse events. CONCLUSION: Amlodipine was a well-tolerated and effective antihypertensive agent, and did not reduce regional cerebral blood flow in elderly hypertensive patients.     

A noninferiority comparison of valsartan/hydrochlorothiazide combination versus amlodipine in black hypertensives

The objective of the study was to demonstrate that reduction in mean 24-hour diastolic blood pressure with 160 mg valsartan and 12.5 mg hydrochlorothiazide was not inferior to 10 mg amlodipine in hypertensive blacks. A total of 482 blacks with stage 1 and stage 2 hypertension (mean seated blood pressure 140 to 180/90 to 110 mm Hg) were enrolled in a double-blind, randomized, prospective study. After a placebo run-in period, patients were randomized to 160 mg valsartan or 5 mg amlodipine for 2 weeks, then force-titrated to 160 mg valsartan and 12.5 mg hydrochlorothiazide or 10 mg amlodipine for an additional 10 weeks. Blood pressure was assessed by 24-hour ambulatory blood pressure monitoring. Other assessments included quality of life, peripheral edema, and safety. Noninferiority of valsartan/hydrochlorothiazide to amlodipine was demonstrated by comparable reductions in mean 24-hour diastolic blood pressure with both treatments (-10.2+/-8.6 mm Hg versus -9.1+/-8.3 mm Hg, respectively; P<0.001 for noninferiority), as well as in mean 24-hour systolic blood pressure (-15.9+/-12.1 mm Hg versus -14.5+/-12.2 mm Hg; P<0.001 for noninferiority). The proportion of patients reporting adverse events and the incidence of most events were similar in both treatment groups, although more patients treated with amlodipine reported peripheral edema (5.8% versus 1.7%; P=0.03) and joint swelling (2.9% versus 0%; P=0.008) compared with valsartan/hydrochlorothiazide. We conclude that a starting dose of valsartan/hydrochlorothiazide (160/12.5 mg) is as effective as high-dose amlodipine (10 mg) in reducing blood pressure in blacks with stage 1 and stage 2 hypertension, and valsartan/hydrochlorothiazide is better tolerated.     

Ambulatory 24-h blood pressure assessment of the felodipine-metoprolol combination versus amlodipine in mild to moderate hypertension. Lorraine General Physician Investigators Group.

OBJECTIVE: To measure the time effect profiles of a once daily administered combination tablet felodipine-metoprolol 5/50 mg (Logimax, Astra) and amlodipine 5 mg (Norvasc, Pfizer) on blood pressure and heart rate using 24-h ambulatory blood pressure monitoring. DESIGN: Randomized multicentre parallel-group study with a single-blind placebo run-in period of 4 weeks duration and a 6-week double-blind active treatment period. PATIENTS AND METHODS: Out of 245 randomized outpatients (90 men, 155 women) with uncomplicated mild-to-moderate primary hypertension and mean sitting diastolic blood pressure (DBP) 95-115 mmHg inclusive, 212 (102 on felodipine-metoprolol, 110 on amlodipine) were eligible for analysis. 24-h ambulatory blood pressure monitoring was performed at the end of the placebo run-in (baseline) and after 6 weeks active treatment (posttreatment). RESULTS: Both felodipine-metoprolol and amlodipine induced smooth and consistent reduction in DBP and systolic blood pressure throughout the 24-h period, hence not altering the diurnal rhythm. However, felodipine-metoprolol reduced all average blood pressures (24-h, day- and night-time) more than amlodipine (for 24-h average blood pressure 14.4/9.5 mmHg and 8.9/5.5 mmHg, respectively). Medians of individual diastolic trough-to-peak (T/P) ratios were similar for felodipine-metoprolol and amlodipine (54 and 50%, respectively), while for the systolic T/P ratios, the corresponding values were 74 and 35%, repectively; no significant difference between treatments was seen. As distinguished from amlodipine, both heart rate and rate pressure product were markedly decreased on felodipine-metoprolol throughout the 24-h period and even during the early morning hours. In general, both treatments were well tolerated. CONCLUSIONS: Both felodipine-metoprolol and amlodipine achieved optimal control of blood pressure during the inter-dosing interval in line with their pharmokinetic profiles. The vasodilatory adverse events were slightly more reported with felodipine-metoprolol combination, but due to more pronounced lowering of the average blood pressures and the potent additional effect on heart rate and rate pressure product, the efficacy/tolerability balance seems to be equal to or better than that obtained with monotherapy such as amlodipine.     

Monitoring 24-hour blood pressure in a drug trial. Evaluation of a noninvasive device

To test the usefulness of noninvasive ambulatory 24-hour blood pressure recording, the Del Mar Avionics system was used in a double-blind clinical trial in which 31 hypertensive patients were randomly allocated to receive placebo or pafenolol (25 mg or 50 mg), a novel, long-acting, highly selective beta-blocker, once daily. The results of 24-hour blood pressure and heart rate recording after 4 weeks of treatment were compared with a previous 24-hour recording performed after a 4-week placebo run-in period using the 3-hour mean of recordings performed every 7.5 minutes both day and night. Furthermore, 24-hour means were analyzed in each patient before and after 4 weeks. The system was easy to use and, judging from two placebo periods in the same patients, the reproducibility was good. The 24-hour blood pressure and heart rate recordings showed a clear dose-response relationship for pafenolol that could not be detected by ordinary casual readings. A daily dose of 25 mg of pafenolol significantly reduced blood pressure during the 9 hours after tablet intake (p less than 0.01), while 50 mg per day of pafenolol resulted in a significant reduction throughout the 24-hour period (p less than 0.01). The same pattern was seen for heart rate, which indicates a greater degree of beta-blockade during treatment with the higher dose. These results indicate that the tested noninvasive equipment is a useful tool for monitoring ambulatory 24-hour blood pressure. It gives important information impossible to obtain from single casual readings. This noninvasive method should be further evaluated to define its place in clinical work and as a research tool.     

The effects of missing a dose of enalapril versus amlodipine on ambulatory blood pressure

OBJECTIVE: To compare the antihypertensive actions of amlodipine and enalapril in a double-blind, randomized, parallel-group study during treatment and when missing a dose. METHOD: After a single-blind run-in 4-week placebo period, patients were randomly allocated to receive enalapril (15 patients) or amlodipine (15 patients). Patients received active treatment for 4 weeks (20 mg enalapril or 5 mg amlodipine). For those with sitting diastolic office pressure not below 90 mmHg the dosage was doubled and continued up to week 12. Ambulatory blood pressure monitoring was performed at the end of the placebo run-in period for 24 h and at the end of week 12 for 48 h; in this case, patients took the active tablet at 0700 h of the first day and a placebo tablet on the next day to stimulate a missing dose in a single-blind manner. RESULTS: Of the patients, 60% had office blood pressure controlled by enalapril therapy and 80% had amlodipine therapy. The average dosage was 30.7 mg a day for enalapril and 7.3 mg a day for amlodipine. Reductions in blood pressures were higher for the amlodipine group. Ambulatory blood pressure measurement shows a reduction in systolic and in diastolic blood pressure during the 24 h when patients from both groups were receiving their medication with respect to placebo values. During the second day of ambulatory blood pressure recording, when the patient had taken a placebo tablet instead of an active one, the antihypertensive effect was progressively lost with enalapril, but not with amlodipine. CONCLUSION: Enalapril and amlodipine reduced ambulatory systolic and diastolic blood pressure during treatment; however, when patients missed an enalapril dose, control of blood pressure was progressively lost, whereas patients receiving amlodipine maintained their blood pressure under control up to 48 h after the last dose.     

Prolonged antihypertensive effect of amlodipine: a prospective double-blind randomized study.

Amlodipine is a calcium antagonist with a long elimination half-life (35 to 50 h) allowing a once daily dosing in the treatment of hypertension. This randomized, double-blind study was performed to assess the residual antihypertensive effect of amlodipine 5 mg O.D. 3 days after discontinuing therapy in previously well-controlled mild to moderate hypertensive patients. Blood pressure (BP) was evaluated by conventional (OBP) and by ambulatory blood pressure monitoring (ABPM). Amlodipine 5 mg OD administered during a 6-week period, significantly reduced both OBP and ABPM mean values (p < 0.05), whereas no change in heart rate was observed. At the end of the active treatment period, adequately controlled patients were randomized either to amlodipine 5 mg OD (group A) or amlodipine for 12 days followed by a 3-day period on placebo. After this double-blind treatment phase, group P exhibited no significant increase in BP (assessed by OBP or ABPM) when compared to group A. In conclusion, the duration of action of amlodipine extends largely beyond the 24-h span, and when patients omit their treatment for 3 days BP does not significantly increase.     

Management of hypertension in patients with diabetes using an amlodipine-, olmesartan medoxomil-, and hydrochlorothiazide-based titration regimen

The safety and efficacy of an amlodipine/olmesartan medoxomil (OM)-based titration regimen was assessed in patients with type 2 diabetes mellitus and hypertension. After a 2- to 3-week placebo run-in period, 207 patients received amlodipine 5 mg and were uptitrated to amlodipine/OM 5/20, 5/40, and 10/40 mg and then amlodipine/OM 10/40 mg plus hydrochlorothiazide 12.5 and 25 mg in a step-wise manner at 3-week intervals if the seated blood pressure (BP) remained ≥120/70 mm Hg. The primary end point was the change from baseline in the mean 24-hour ambulatory systolic BP after 12 weeks of treatment. The baseline mean ± SD seated cuff systolic/diastolic BP was 158.8 ± 13.1/89.1 ± 10.1 mm Hg and the mean ± SD 24-hour ambulatory systolic/diastolic BP was 144.4 ± 11.7/81.6 ± 9.8 mm Hg. At week 12, the change from baseline in the mean ± SEM 24-hour ambulatory systolic/diastolic BP was -19.9 ± 0.8/-11.2 ± 0.5 mm Hg (p<0.0001 vs baseline), and 70% of patients had achieved a 24-hour ambulatory BP target of <130/80 mm Hg. At the end of 18 weeks of active treatment in patients uptitrated to amlodipine/OM 10/40 mg plus hydrochlorothiazide 25 mg, the change from baseline in the mean ± SEM seated BP was -28.0 ± 1.5/-13.7 ± 1.0 mm Hg (p<0.0001 vs baseline), with 62% of patients reaching the guideline-recommended seated BP goal of <130/80 mm Hg. Drug-related treatment-emergent adverse events occurred in 19.3% of patients. The most frequent events were peripheral edema (6%), dizziness (3%), and hypotension (2%). In conclusion, this amlodipine/OM-based titration regimen was well tolerated and effectively lowered BP throughout the 24-hour dosing interval in patients with hypertension and type 2 diabetes.     

Double-blind, randomized, multicentre comparison of the effects of amlodipine and perindopril on 24 h therapeutic coverage and beyond in patients with mild to moderate hypertension. General Physicians Investigators' Group

OBJECTIVE: To compare the therapeutic coverage and safety of amlodipine and perindopril in patients with mild to moderate hypertension (diastolic blood pressure > or = 90 mmHg and < or = 109 mmHg). DESIGN: A double-blind, randomized, parallel-group, multicentre study. METHODS: Following a 2-week placebo wash-out period, the patients were randomly allocated to treatment with either amlodipine at 5-10 mg once a day or perindopril at 4-8 mg once a day, for 60 days. Trough: peak ratios were calculated by two different methods (global and individualized approaches) from 24 h ambulatory blood pressure recordings made after the placebo period and after the active treatment period. Residual lowering of blood pressure after single-blind, single-dose omission was also investigated with further 24 h ambulatory blood pressure monitoring. Safety assessments were made throughout the study. RESULTS: The placebo-adjusted, global, diastolic blood pressure trough: peak ratio was 0.80 in the amlodipine group (n = 47) and 0.81 in the perindopril group (n = 49) in an intent-to-treat analysis. The corresponding global systolic blood pressure trough: peak ratio was 0.83 for amlodipine and 0.68 for perindopril. Individual trough: peak ratios were non-normally distributed. Mean (+/- SD) individual trough: peak ratios (intent-to-treat analysis) for diatolic blood pressure were 0.50 +/- 0.69 for amlodipine (median 0.42) and 0.15 +/- 3.27 for perindopril (median 0.33). In the per protocol analysis, the corresponding values were 0.50 +/- 0.72 (median 0.34) for amlodipine and 0.01 +/- 3.90 for perindopril (median 0.21). Both treatments produced comparable decreases in clinic systolic and diastolic blood pressure between days 0 and 60. Forty-eight hours after the last dose, both systolic and diastolic blood pressure were lower in amlodipine-treated patients than perindopril-treated patients. Amlodipine and perindopril were generally well tolerated. The most frequently reported adverse event was leg oedema in amlodipine-treated patients (19.1%), and coughing in perindopril-treated patients (14.3%). CONCLUSIONS: These results showed no statistically significant difference in trough: peak ratios between amlodipine and perindopril. However, the ambulatory blood pressure trough: peak ratios showed very large variations. Determination of trough: peak ratios by the conventional approach or by an individual approach can yield disparate values. After omitting one dose, a condition imitating noncompliance, blood pressure was more effectively controlled with amlodipine than with perindopril.     

Antihypertensive efficacy and safety of olmesartan medoxomil compared with amlodipine for mild-to-moderate hypertension

The antihypertensive efficacy of the angiotensin II receptor blocker olmesartan medoxomil has been shown to compare favourably with that of other antihypertensive agents. This randomized, double-blind study compared the antihypertensive efficacy of the starting dose of olmesartan medoxomil with that of the calcium channel blocker amlodipine besylate (amlodipine) in subjects with mild-to-moderate hypertension. Following a 4-week, single-blind, placebo run-in period, 440 subjects aged >/=18 years were randomized to the starting dose of olmesartan medoxomil (20 mg/day), amlodipine (5 mg/day), or placebo for 8 weeks. Subjects were evaluated by 24-h ambulatory blood pressure monitoring (ABPM) and by seated cuff blood pressure (BP) measurements at trough. The primary end point was the change from baseline in mean 24-h diastolic blood pressure (DBP) by ABPM at Week 8. Secondary end points included change from baseline in mean 24-h ambulatory systolic blood pressure (SBP) at 8 weeks, change from baseline in mean seated trough cuff DBP and SBP measurements, and response and control rates for DBP <90 and <85 mmHg. Control rates for SBP <140 and <130 mmHg were also calculated. Olmesartan medoxomil and amlodipine produced significantly greater reductions in ambulatory and seated DBP and SBP compared with placebo. Mean reductions in ambulatory and seated BP were similar between the two active agents; however, in the olmesartan medoxomil group, significantly more patients achieved the SBP goal of <130 mmHg and the DBP goal of <85 mmHg. Both drugs were well tolerated at the recommended starting dose. Although amlodipine was associated with a higher incidence of oedema, this did not reach statistical significance. Olmesartan medoxomil is an effective antihypertensive agent, with BP-lowering efficacy at the starting dose similar to that of amlodipine, and is associated with more patients achieving the rigorous BP goals of SBP <130 mmHg and DBP <85 mmHg.     

Use of 24-h ambulatory blood pressure monitoring to assess blood pressure control: a comparison of olmesartan medoxomil and amlodipine besylate

OBJECTIVE: Olmesartan medoxomil is an angiotensin II receptor blocker with similar antihypertensive efficacy as the calcium channel blocker amlodipine besylate in patients with mild-to-moderate hypertension. In addition to a drug's ability to lower blood pressure, the effectiveness of the agent in enabling patients to achieve specific blood pressure targets is an important clinical consideration. This secondary analysis of a randomized, double-blind study compared the efficacy of olmesartan medoxomil with that of amlodipine besylate in achieving ambulatory blood pressure goals among patients with mild-to-moderate hypertension. METHODS: Following a 4-week placebo run-in, 440 study participants aged >or=18 years were randomized to olmesartan medoxomil (20 mg/day), amlodipine besylate (5 mg/day), or placebo for 8 weeks. The proportion of participants achieving specific systolic and diastolic ambulatory blood pressure goal levels was calculated by dividing the number of participants who had achieved a particular blood pressure goal by the total number of patients in the intent-to-treat population. RESULTS: After 8 weeks of treatment, a mean 24-h ambulatory blood pressure of <130/80 or <130/85 mmHg was achieved by significantly more participants in the olmesartan medoxomil group (18.1 and 30.4%, respectively) than in the amlodipine besylate (7.0 and 14.0%, respectively) or placebo (1.9% for both) groups. The target daytime ambulatory blood pressure of <135/85 mmHg was achieved by more participants in the olmesartan medoxomil group than in the amlodipine besylate group (15.8 vs. 5.8%, respectively; P<0.01). CONCLUSION: In a previous publication of the same study, we demonstrated that starting doses of olmesartan medoxomil and amlodipine besylate produced similar mean reductions in blood pressure. In this subanalysis of the blood pressure data from that primary publication, however, olmesartan medoxomil therapy was shown to result in a greater proportion of patients achieving specific ambulatory blood pressure goals than therapy with amlodipine besylate. As blood pressure goal attainment may be of more direct clinical relevance than numerical blood pressure lowering, the achievement of blood pressure goals should be a key efficacy parameter assessed in clinical trials of antihypertensive medications.     

Combination therapy with amlodipine and captopril for resistant systemic hypertension

This study was conducted to assess the therapeutic utility of combining amlodipine with captopril in patients with moderate-to-severe hypertension. Patients had hypertension of WHO grades I–III, with initial mean sitting and standing diastolic blood pressure of 100–119 mm Hg (phase V) after 2–4 weeks on placebo, and had remained uncontrolled (diastolic blood pressure > 95 mm Hg) despite a further 4 weeks on low-dose captopril. Twenty-nine patients entered the computer-randomized, double-blind, placebocontrolled, 2-way crossover comparison of either amlodipine 10 mg once daily or matching placebo added to continued therapy with captopril 25 mg twice daily for 4 weeks. Patients then acted as their own control and received the alternative amlodipine/placebo treatment plus their continued captopril therapy for another 4 weeks. Once-daily amlodipine was shown to be effective when combined with captopril. Mean baseline supine systolic blood pressure decreased from 167 to 149 mm Hg and standing systolic blood pressure from 167 to 144 mm Hg. Mean supine diastolic blood pressure decreased from 105 to 92 mm Hg, and standing diastolic blood pressure decreased from 110 to 96 mm Hg. The placebo-corrected amlodipine differences in mean changes from captopril baseline were −18/−12.2 mm Hg for supine and −20.1/−11.9 mm Hg for standing systolic and diastolic blood pressures, respectively (p < 0.001 for all 4 measurements). The most common side effects encountered with amlodipine were flushing and pedal edema. The combination of amlodipine and captopril was well tolerated, and no patient discontinued therapy. No significant treatment-related effects on biochemical and hematologic parameters were noted.     

Are there differences in the effects of long-acting calcium antagonists on ambulatory blood pressure? Extended-release nisoldipine versus amlodipine as a model

BACKGROUND: Twenty-four-hour ambulatory blood pressure monitoring (ABPM), which provides important information regarding mean 24 h efficacy, variability of effect during sleeping-awake cycles, and effects on the early morning surge in blood pressure, is a sensitive method for evaluating efficacy of antihypertensive agents. Extended-release nisoldipine and amlodipine are long-acting dihydropyridine calcium antagonists used for the treatment of hypertension. Because these agents have different pharmacokinetic profiles, 24 h ABPM could provide clues regarding their different effects on blood pressure. OBJECTIVE: To assess the effects of extended-release nisoldipine and amlodipine on 24 h ambulatory blood pressure control and heart rate. METHODS: After completion of a 3-4 week placebo run-in period, 100 patients were randomly allocated to double-blind treatment with 10-40 mg extended-release nisoldipine or 2.5-10 mg amlodipine for 8 weeks, starting at the lowest dose. Medications were titrated at 2-week intervals on the basis of office blood pressures in seated patients. Twenty-four-hour ABPM was performed at placebo baseline and at the end of double-blind therapy. RESULTS: Extended-release nisoldipine and amlodipine provided equivalent mean 24 h changes in blood pressure [systolic blood pressure (SBP)/diastolic blood pressure decreases by 9.8/7.1 and 8.0/6.0 mmHg, respectively] and heart rate. These two treatments also provided similar changes in blood pressure at trough (22-24 h after dosing; decreases by 10.4/7.2 and 10.1/7.3 mmHg, respectively). The antihypertensive effects of amlodipine during the awake and sleeping intervals were similar (decreases by 9.6/5.9 and 9.9/5.8 mmHg, respectively, NS); whereas the effect of nisoldipine during the awake interval was significantly greater than its effect during the sleeping interval (decreases by 12.4/8.0 and 8.9/4.3 mmHg, respectively, P = 0.08/0.01). Furthermore, extended-release nisoldipine, but not amlodipine, blunted the rate of rise in early morning SBP. CONCLUSIONS: Extended-release nisoldipine and amlodipine have similar effects on mean 24 h and trough blood pressures. However, different effects during the sleeping and awake intervals and on the rate of rise in early morning SBP were observed with nisoldipine.     

Crossover comparison of atenolol, enalapril, hydrochlorothiazide and isradipine for isolated systolic systemic hypertension.

The benefit of antihypertensive therapy in reducing cardiovascular morbidity and mortality associated with isolated systolic hypertension has now been established by the Systolic Hypertension in the Elderly Program. However, there is little information about the relative effectiveness of different drug regimens in this condition. This study compared the efficacy and tolerability of 50 mg of atenolol, 10 mg of enalapril, 25 mg of hydrochlorothiazide and 2.5 mg of isradipine in the treatment of isolated systolic hypertension. After a 3-week placebo run-in phase, 24 subjects were randomized into a 4-period double-blind crossover study by use of an orthogonal latin square design. Treatment periods were of 6 weeks' duration with titration to a higher dose after 4 weeks in those not reaching goal blood pressure (BP). Each active treatment was followed by a 3-week placebo washout. Casual clinic and 24-hour ambulatory BP (Accutracker II) were measured at the end of each treatment phase. Routine biochemistry was also performed after the placebo run-in, at the end of each active treatment phase, and after the placebo run-out. Of the 24 subjects entered (mean age 72.3 years, 38% men) 20 completed the whole study. Mean +/- standard deviation of supine clinic and daytime ambulatory BP on entry were 181/79 +/- 21/9 mm Hg and 165/82 +/- 23/15 mm Hg, respectively. All drugs reduced mean casual and ambulatory BP significantly relative to placebo but only hydrochlorothiazide and enalapril produced a consistent hypotensive effect throughout the entire 24-hour period. Isradipine and enalapril exhibited a relatively greater effect on reducing systolic BP than either hydrochlorothiazide or atenolol.(ABSTRACT TRUNCATED AT 250 WORDS)     

Long-term intake of North American ginseng has no effect on 24-hour blood pressure and renal function

Ginseng is consumed by 10% to 20% of adults in Asia and by up to 5% in Western countries. Despite observational evidence suggesting a link between its intake and the development of hypertension, there remains no long-term scrutiny for its effect on blood pressure (BP). We therefore undertook a randomized, placebo-controlled, double-blinded, crossover trial in 52 hypertensive individuals to determine the effect of 12-week North American ginseng intake on 24-hour BP; we also measured serum cystatin C as a marker of renal function. After a 4-week placebo run-in, we randomly assigned 52 participants to 3 g/day of ginseng or placebo for 12 weeks. This was followed by an 8-week washout and a subsequent 12-week period in which the opposite treatment was administered. At run-in and at weeks 0 and 12 of each treatment period, participants were fitted with an ambulatory BP monitor to assess 24-hour BP. The primary outcome was the treatment difference at week 12 in mean 24-hour systolic BP. Secondary outcomes were treatment differences at week 12 in other ambulatory BP parameters and serum cystatin C. Forty participants (77%) completed the trial, with 3 removed from main analysis (n=2, antihypertensive drug changes; n=1, incomplete ambulatory monitoring). In the remaining 37, 12-week ginseng treatment was associated with a neutral effect on all ambulatory BP parameters compared with placebo; an intention-to-treat analysis supported this. Ginseng did not affect serum cystatin C level. Overall, long-term ginseng use had no effect on 24-hour BP and renal function in hypertensive individuals.     

Nocturnal reduction of blood pressure and the antihypertensive response to a diuretic or angiotensin converting enzyme inhibitor in obese hypertensive patients

During a 12-week, multicenter study to evaluate the efficacy and safety of lisinopril and hydrochlorothiazide (HCTZ) for the treatment of obesity-related hypertension, ambulatory blood pressure (ABP) monitoring was performed both at baseline and at study completion in 124 patients. Patients were randomized to three groups: placebo, lisinopril (10, 20, or 40 mg/day), or HCTZ (12.5, 25, or 50 mg/day). All groups were matched with regard to sex, race, age, body mass index, and waist/hip ratio. The primary analysis of ABP data revealed that both lisinopril and HCTZ effectively lowered mean 24-h systolic (SBP) and diastolic (DBP) blood pressure compared with placebo, (mean change from baseline SBP/DBP: −12.0/−8.2, −10.6/−5.5, and −0.3/−0.5 mm Hg, respectively); however, lisinopril lowered DBP better than HCTZ (P < .05). Secondary analyses of groups revealed that men responded better to lisinopril than HCTZ (−11.9/−7.3 v −6.6/−3.5 mm Hg, respectively), whereas women responded well to both drugs. White patients responded better to lisinopril than HCTZ, whereas black patients showed a significant response to HCTZ only. Response to treatment was also influenced by patient classification of 24-h blood pressure profiles, ie, “dipper” or “nondipper.” Overall, the majority of obese hypertensives were nondippers. Nondippers (n = 82) responded well to both drugs (−10.4/−6.9 v −12.5/−5.7 mm Hg, P < .05 v placebo), whereas dippers (n = 42) responded to lisinopril (−11.7/−9.4 mm Hg, P < .05 v placebo and HCTZ), but not HCTZ (−5.6/−4.1 mm Hg, P = NS v placebo). Results of 24-h ABP data show that both lisinopril and HCTZ are effective therapies for obesity-related hypertension and that response to treatment is influenced by sex, race, and dipper/nondipper status.     

24-Hour ambulatory blood pressure control with triple-therapy amlodipine, valsartan and hydrochlorothiazide in patients with moderate to severe hypertension

To determine the effectiveness and safety of once-daily combination therapy with amlodipine, valsartan and hydrochlorothiazide for reducing ambulatory blood pressure (ABP) in patients with moderate to severe hypertension, a multicenter, double-blind study was performed (N=2271) that included ABP monitoring in a 283-patient subset. After a single-blind, placebo run-in period, patients were randomized to receive amlodipine/valsartan/hydrochlorothiazide (10/320/25?mg), valsartan/hydrochlorothiazide (320/25?mg), amlodipine/valsartan (10/320?mg) or amlodipine/hydrochlorothiazide (10/25?mg) each morning for 8 weeks. Efficacy assessments included change from baseline in 24-h, daytime and night time mean ambulatory systolic BP (SBP) and diastolic BP (DBP). Statistically significant and clinically relevant reductions from baseline in all these parameters occurred in all treatment groups (P<0.0001, all comparisons versus baseline). At week 8, least squares mean reductions from baseline in 24-h, daytime and night time mean ambulatory SBP/DBP were 30.3/19.7, 31.2/20.5 and 28.0/17.8?mm?Hg, respectively, with amlodipine/valsartan/hydrochlorothiazide; corresponding reductions with dual therapies ranged from 18.8-24.1/11.7-15.5, 19.0-25.1/12.0-16.0 and 18.3-22.6/11.1-14.3?mm?Hg (P≤0.01, all comparisons of triple versus dual therapy). Treatment with amlodipine/valsartan/hydrochlorothiazide maintained full 24-h effectiveness, including during the morning hours; all hourly mean ambulatory SBP and mean ambulatory DBP measurements were ≤130/85?mm?Hg at end point. Amlodipine/valsartan/hydrochlorothiazide combination therapy was well tolerated. Once-daily treatment with amlodipine/valsartan/hydrochlorothiazide (10/320/25?mg) reduces ABP to a significantly greater extent than component-based dual therapy and maintains its effectiveness over the entire 24-h dosing period.     

A randomized, placebo-controlled, double-blind comparison of amlodipine and atenolol in patients with essential hypertension.

The efficacy and safety of amlodipine (2.5 mg, 5 mg, or 10 mg) once daily was compared with atenolol (50 mg to 100 mg) once daily in patients with mild-to-moderate essential hypertension in a randomized, double-blind, parallel, placebo-controlled study. One hundred and twenty-five patients were randomly allocated at the end of a 4-week run-in placebo period to 8 weeks' double-blind treatment with amlodipine (n = 41), atenolol (n = 43), or placebo (n = 41). The mean changes from baseline in blood pressure 24 h postdose for amlodipine (mean daily dose 8.8 mg) were -12.8/-10.1 mm Hg for supine and -11.5/-9.8 mm Hg for standing blood pressure (P < .001). For atenolol (mean daily dose 83.7 mg) the changes were -11.3/-11.7 mm Hg for supine and -13.3/-12.3 mm Hg for standing blood pressure (P < .001). There were no statistically significant differences between treatments. The responder rates for amlodipine, atenolol, and placebo were 61.1%, 64.9%, and 11.1%, respectively. Determinations taken over the 24-h period at the final visit revealed that amlodipine and atenolol maintained the group mean supine blood pressure at or below 140/90 mm Hg throughout the period of observation; the corresponding time-effect curve for the placebo group was clearly in the hypertensive range. Heart rate was significantly lowered by atenolol only. Both amlodipine and atenolol were well-tolerated. Only one patient was withdrawn because of the development of peripheral edema, arthralgia, and fatigue after treatment with amlodipine. This study demonstrates that once-daily administration of amlodipine or atenolol to mild-to-moderate hypertensive patients was well-tolerated and provided adequate blood pressure control throughout the 24-h dosing interval.     

Potassium supplementation reduces clinic and ambulatory blood pressure in elderly hypertensive patients.

OBJECTIVES: To determine the effects of potassium chloride 60 mmol/day supplementation on clinic and 24-h ambulatory blood pressure values in elderly untreated hypertensive patients. DESIGN: A double-blind randomized placebo-controlled crossover study lasting 8 weeks, following a 4-week run-in period. SETTING: Outpatient clinic in a district general hospital. PATIENTS: Eighteen untreated elderly hypertensive patients (mean age 75 years, range 66-79) with a systolic blood pressure of > or = 160 mmHg and/or a diastolic blood pressure of > or = 95 mmHg were recruited from the clinics of local general practitioners and from the current hospital outpatient department. Patients had not received any antihypertensive medication for at least 4 weeks before entry into the study. INTERVENTIONS: Before entry into the study, the daily dietary electrolyte intake of each individual was established and this was maintained during the run-in and intervention periods. Following a 4-week run-in period patients received potassium supplements or matching placebo, each for 4 weeks. MAIN OUTCOME MEASURES: The within-patient changes in clinic and 24-h ambulatory blood pressures at the end of each intervention period. RESULTS: After 4 weeks potassium supplementation compared with placebo there was a significant fall in supine clinic blood pressure, standing and 24-h ambulatory systolic blood pressure. There was no significant change in clinic standing diastolic blood pressure, 24-h ambulatory diastolic blood pressure or pulse rate. Plasma renin activity increased and body weight fell after potassium supplementation. Twenty-four-hour urinary potassium rose significantly, whereas urinary sodium excretion was unchanged. CONCLUSIONS: A 60-mmol daily supplement of potassium chloride reduces clinic and 24-h ambulatory blood pressure in elderly hypertensive patients.     

Lactotripeptides show no effect on human blood pressure: results from a double-blind randomized controlled trial

Milk-derived peptides with ACE-inhibiting properties may have antihypertensive effects in humans. We conducted a randomized double-blind placebo-controlled trial to examine the blood pressure lowering potential of 2 ACE-inhibiting lactotripeptides, ie, Isoleucine-Proline-Proline and Valine-Proline-Proline. We included 135 Dutch subjects with elevated systolic blood pressure who were otherwise healthy and who received no current antihypertensive treatment. After a 2-week run-in period on placebo, subjects randomly received a daily dose of 200 mL dairy drink with 14 mg lactotripeptides obtained by concentrating fermented milk, enzymatic hydrolysis, or chemical synthesis, or placebo for 8 weeks, followed by a 2-week wash-out. The primary outcome was 8-week change in office systolic blood pressure. Secondary outcomes were change in diastolic blood pressure, home blood pressure, 24-hour ambulatory blood pressure, plasma ACE-activity, and plasma angiotensin II. Blood pressure at baseline was on average 142/84 mm Hg. Lactotripeptides did not significantly change systolic blood pressure (P=0.46) or diastolic blood pressure (P=0.31) compared with placebo. The mean difference (95%-CI) in systolic blood pressure response between treatment and placebo was 2.8 mm Hg (-2.6;8.2) for concentrated fermented milk lactotripeptides, -0.5 mm Hg (-6.0;5.0) for enzymatic lactotripeptides, and 1.6 mm Hg (-3.9;6.9) for synthetic lactotripeptides. Treatment neither had a significant effect on secondary outcome measures. In conclusion, the present study does not support the hypothesis of a blood pressure lowering effect of the lactotripeptides Isoleucine-Proline-Proline and Valine-Proline-Proline.