Amlodipine reduces blood pressure during dynamic resistance exercise in hypertensive patients

This study investigated the effect of the dihydropyridine calcium channel antagonist, amlodipine, on blood pressure (BP) during resistance exercise performed at different intensities in hypertensives. Eleven hypertensives underwent 4 weeks of placebo and amlodipine (random double-blinded crossover design). In each phase, they performed knee extension exercise until exhaustion following three protocols: one set at 100% of 1 RM (repetition maximum), three sets at 80% of 1 RM, and three sets at 40% of 1 RM. Intraarterial BP was measured before and during exercise. Amlodipine reduced maximal systolic/diastolic BP values achieved at all intensities (100% = 225 ± 6/141 ± 3 vs. 207 ± 6/130 ± 6 mmHg; 80% = 289 ± 8/178 ± 5 vs. 273 ± 10/169 ± 6 mmHg; 40% = 289 ± 10/176 ± 8 vs. 271 ± 11/154 ± 6 mmHg). Amlodipine blunted the increase in diastolic BP that occurred during the second and third sets of exercise at 40% of 1RM (+75 ± 6 vs. +61 ± 5 mmHg and +78 ± 7 vs. +64 ± 5 mmHg, respectively). Amlodipine was effective in reducing the absolute values of systolic and diastolic BP during resistance exercise and in preventing the progressive increase in diastolic BP that occurs over sets of low-intensity exercise. These results suggest that systemic vascular resistance is involved in BP increase during resistance exercise, and imply that hypertensives receiving amlodipine are at lower risk of increased BP during resistance exercise than non-medicated patients.

Previous exercise attenuates muscle sympathetic activity and increases blood flow during acute euglycemic hyperinsulinemia

Insulin infusion causes muscle vasodilation, despite the increase in sympathetic nerve activity. In contrast, a single bout of exercise decreases sympathetic activity and increases muscle blood flow during the postexercise period. We tested the hypothesis that muscle sympathetic activity would be lower and muscle vasodilation would be higher during hyperinsulinemia performed after a single bout of dynamic exercise. Twenty-one healthy young men randomly underwent two hyperinsulinemic euglycemic clamps performed after 45 min of seated rest (control) or bicycle exercise (50% of peak oxygen uptake). Muscle sympathetic nerve activity (MSNA, microneurography), forearm blood flow (FBF, plethysmography), blood pressure (BP, oscillometric method), and heart rate (HR, ECG) were measured at baseline (90 min after exercise or seated rest) and during hyperinsulinemic euglycemic clamps. Baseline glucose and insulin concentrations were similar in the exercise and control sessions. Insulin sensitivity was unchanged by previous exercise. During the clamp, insulin levels increased similarly in both sessions. As expected, insulin infusion increased MSNA, FBF, BP, and HR in both sessions (23 ± 1 vs. 36 ± 2 bursts/min, 1.8 ± 0.1 vs. 2.2 ± 0.2 ml·min−1·100 ml−1, 89 ± 2 vs. 92 ± 2 mmHg, and 58 ± 1 vs. 62 ± 1 beats/min, respectively, P < 0.05). BP and HR were similar between sessions. However, MSNA was significantly lower (27 ± 2 vs. 31 ± 2 bursts/min), and FBF was significantly higher (2.2 ± 0.2 vs. 1.8 ± 0.1 ml·min−1·100 ml−1, P < 0.05) in the exercise session compared with the control session. In conclusion, in healthy men, a prolonged bout of dynamic exercise decreases MSNA and increases FBF. These effects persist during acute hyperinsulinemia performed after exercise.

Amlodipine 2.5???mg once daily in older hypertensives: a Brazilian multi-centre study

OBJECTIVES

The use of low-dose amlodipine has not yet been well established in the elderly. This study therefore aimed to evaluate the efficacy and tolerability of low-dose amlodipine in elderly patients with Joint National Committee VI stage I or II hypertension.

PATIENTS AND METHODS

Sixty-five hypertensive individuals (aged 66.3 +/- 5.3 years) received amlodipine 2.5 mg per day for 12 weeks before and after two periods of 4 weeks of placebo. At weeks 0, 12 and 16, patients were submitted to office, 24 h ambulatory blood pressure monitoring and home blood pressure measurement.

RESULTS

Office systolic and diastolic blood pressure showed decreases at weeks 8 (153 +/- 17, 90 +/- 9 mmHg) and 12 (152 +/- 16, 90 +/- 9 mmHg) compared with weeks 0 (164 +/- 16, 99 +/- 6 mmHg) and 16 (162 +/- 19, 95 +/- 9 mmHg). During ambulatory monitoring, a decrease was observed in the average 24 h systolic and diastolic pressure at week 12 (143 +/- 13, 86 +/- 7 mmHg) compared with weeks 0 (155 +/- 15, 93 +/- 6 mmHg) and 16 (152 +/- 16, 92 +/- 8 mmHg). A daytime and night-time reduction in systolic and diastolic pressure was observed on home blood pressure monitoring at week 12 (146 +/- 16/88 +/- 8, 144 +/- 16/93 +/- 8 mmHg) compared with weeks 0 (159 +/- 17/94 +/- 8, 161 +/- 19/93 +/- 8 mmHg) and 16 (153 +/- 16/93 +/- 8, 154 +/- 17/92 +/- 8 mmHg). Adverse reactions were infrequent.

CONCLUSIONS

Amlodipine at a dose of 2.5 mg per day showed efficacy and good tolerability in elderly hypertensives.

Factors affecting post-exercise hypotension in normotensive and hypertensive humans

BACKGROUND

Post-exercise hypotension has been extensively described under laboratory conditions. However, studies investigating the persistence of this post-exercise decrease in blood pressure for longer periods have produced controversial results. The present investigation was conducted to verify the effect of a single bout of exercise on ambulatory blood pressure and to identify potential factors that might influence this post-exercise ambulatory blood pressure fall.

DESIGN

The study was a randomized controlled clinical trial.

METHODS

Thirty normotensive and 23 hypertensive subjects were submitted to two ambulatory blood pressure monitorings (using the SpaceLabs 90207, SpaceLabs, Redmond, Washington, USA), which were performed after 45min of seated rest (control session) or cycling exercise at 50% peak oxygen uptake (exercise session).

RESULTS

Normotensive subjects demonstrated a lower 24h blood pressure level in the exercise session. Hypertensive patients showed no significant difference in ambulatory blood pressure level between the two experimental sessions. Further data analysis revealed that approximately 65% of the subjects in both groups experienced a fall in blood pressure after exercise. Moreover, in the normotensive subjects, this blood pressure fall was significantly and positively correlated with clinic and ambulatory blood pressure, and negatively correlated with weight and body mass index. The blood pressure response to exercise was also greater in women. In the hypertensive patients, the post-exercise blood pressure decrease was significantly and positively correlated with clinic and ambulatory blood pressure as well as with the peak oxygen uptake, and negatively correlated with age and body mass index.

CONCLUSIONS

The post-exercise ambulatory blood pressure fall observed in normotensive and hypertensive humans depends on individual characteristics. Moreover, in both normotensive and hypertensive humans, post-exercise ambulatory hypotension is greater in subjects with a higher initial blood pressure level.

[Single daily dose of verapamil (COER-24 180/24 mg) in mild and moderate hypertension evaluated by ambulatory blood pressure monitoring]

OBJECTIVE

To evaluate the anti-hypertensive effect of verapamil COER-24 180/240 mg in a single dose at bedtime as single therapy in mild to moderate hypertensives.

METHODS

A multicentric, open, placebo controlled study of 81 hypertensive patients older than 20 years-old followed to 8 weeks. Blood pressure was measured in doctor's office and by 24 h ambulatory monitoring (ABPM).

RESULTS

We observed a decreased in systolic and diastolic blood pressure in doctor's office at 4th and 8th weeks. ABPM showed that both systolic, diastolic and mean blood pressure, heart rate and the mean 24-hour blood pressure load decreased after the 8-week treatment. In addition, there was a reduction of the double-product, especially in the morning and 68% of the patients didn't have any adverse events.

CONCLUSION

The therapy verapamil COER-24 180/240 mg in a single dose is useful for mild and moderate hypertensive patients, with significant pressure decrease in both office blood pressure measurements and in the ABPM/24 hours, as well as showing good tolerability.

Postexercise responses of muscle sympathetic nerve activity and blood flow to hyperinsulinemia in humans

Although insulin and exercise cause dramatic changes in physiological parameters, the impact of exercise on neural and hemodynamic responses to insulin administration has not been described. In a study of the effects of a single bout of exercise on blood pressure (BP), muscle sympathetic nerve activity (MSNA), and forearm blood flow (FBF) responses to insulin infusion during the postexercise period, 11 healthy men underwent, in a random order, two hyperinsulinemic euglycemic clamps performed after 45 min of 1) bicycle exercise (50% peak O(2) uptake, Exercise session) and 2) seated rest (Control session). Data were analyzed during baseline and steady-state periods. Although insulin levels and insulin sensitivity were similar, baseline plasma glucose levels were significantly lower in the Exercise than in the Control session. Mean BP was significantly lower (3%) and FBF was higher (27%) in the Exercise session. Exercise increased insulin-induced MSNA enhancement (84%) without changing FBF and BP responses to hyperinsulinemia. In conclusion, a single bout of exercise that does not alter insulin sensitivity exacerbates insulin-induced increase in MSNA without changing FBF and BP responses to hyperinsulinemia.

[Efficacy and tolerance of the bisoprolol/hydrochlorothiazide combination in arterial hypertension]

PURPOSE

Multicenter, open and non-controlled study to evaluated the efficacy and the tolerability of a low-dose combination of two anti-hypertensive agents: a cardioselective beta-blocker, bisoprolol (2.5 and 5.0 mg) with 6.25 mg of hydrochlorothiazide.

METHODS

One hundred and six patients in the stage I and stage II of the systemic hypertension (mild to moderate) were given the bisoprolol/hydrochlorothiazide combination once daily and the diastolic and systolic blood pressures were monitored during the 8-week trial.

RESULTS

The bisoprolol/hydrochlorothiazide combination reduced the initial mean values of systolic and diastolic blood pressures, respectively, from the 157.4 mmHg and 98.8 mmHg to 137.3 mmHg and 87.4 mmHg. At the end of the treatment period, 61% of the patients normalized blood pressure values (< 90 mmHg) and 22.9% of them had responded to the treatment, resulting in a total response rate (normalized + responsive) of 83.9% of cases. Adverse events were described only in 18.9% of the patients and dizziness and headache were the most common. There were no clinically significant changes on plasma levels of potassium, uric acid, glucose, or in the lipid profile.

CONCLUSION

The combination of low dosages of bisoprolol and hydrochlorothiazide may be considered an effective, well tolerated and rational alternative for the initial treatment of the patients with mild to moderate hypertension.

[Treatment of mild and moderate hypertension with diltiazem 240mg. Brazilian multicenter trial]

PURPOSE

The efficacy and safety of diltiazen 240mg was evaluated in essential hypertensive patients with diastolic pressure in the range of 95 to 115 mmHg.

METHODS

In an open, non-comparative multicenter trial 2.165 hypertensives had the supine and orthostatic arterial blood pressure measured before, after 14 days with non pharmacologic therapy and after 40 days taking diltiazen 240mg/day. Also, the serum levels of lipids, glucose and electrolytes were measured before and after the use of the active drug.

RESULTS

The systolic arterial pressure in the first day was 166 +/- 18mmHg, in the 14th day was 155 +/- 20mmHg; and, in the 54th day was 141 +/- 14mmHg (p < 0.05). Also, supine and orthostatic diastolic blood pressure was lower in the 14th and in the 54th days when compared to baseline (p < 0.05). Cholesterol, triglycerides, urea and uric acid levels decreased significantly (p < 0.05) during treatment.

CONCLUSION

This study demonstrates that diltiazem 240mg/day for the treatment of hypertension is well tolerated, efficient and shows no metabolic undesirable effects.