When the blood pressure lowering effect of beta-blockers from this review was compared to that of thiazide diuretics from our previous review ( Chen 2009 ) , second-line beta-blockers reduce systolic BP to the same extent as second-line thiazide diuretics , but reduce diastolic BP to a greater degree .
The different effect on diastolic BP means that beta-blockers have little or no effect on pulse pressure whereas thiazides cause a significant dose-related decrease in pulse pressure .
This difference in the pattern of BP lowering with beta-blockers as compared to thiazides might be the explanation for the fact that beta-blockers appear to be less effective at reducing adverse cardiovascular outcomes than thiazide diuretics , particularly in older individuals
BACKGROUND Beta-blockers are one of the more commonly prescribed classes of anti-hypertensive drugs , both as first-line and second-line .
OBJECTIVES To quantify the effect on systolic blood pressure ( SBP ) , diastolic blood pressure ( DBP ) , heart rate and withdrawals due to adverse effects of beta-blocker therapy when given as a second-line drug in adult patients with primary hypertension .
Atenolol and chlorthalidone in combination for hypertension.
1 The hypotensive effect of single daily dosing with atenolol 100 mg and chlorthalidone 25 mg given alone or in combination has been assessed in a double-blind , crossover , placebo controlled trial in fifteen hypertensive patients . 2 Average lying blood pressures were : Placebo 155.4/103.9 mm Hg , atenolol 134.6/85.8 mm Hg , chlorthalidone 139.5/90.1 mm Hg , combination 127.7/82.5 mm Hg . 3 The effect of the combination therapy in reducing lying diastolic pressure compared with placebo ( a fall of 21.4 mm Hg ) was significantly less than the 31.9 mm Hg fall predicted from the sum of the individual effects ( P = 0.01 ) . 4 Observations on blood pressure at rest and under mental , isometric and bicycle ergometer stress were made pre-dose and post-dose for a 12 h period at the end of the last treatment period . 5 Lying blood pressure declined from the zero hour ( pre-dose ) reading on all treatments to a low at 15.00 - -18.00 h and then rose again . 6 The rise in systolic blood pressure after isometric exercise and mental stress was of a similar magnitude with all four treatment regimes . 7 Atenolol , alone and in combination with chlorthalidone , reduced the blood pressure and the pulse rate increase on exercise 2 h post-dose when compared with readings 24 h post-dose . 8 Once daily dosing with a combination of atenolol and chlorthalidone produced a fall in supine blood pressure over a 24 h period but the effect on exercise induced changes was not uniform over this period
When the blood pressure lowering effect of beta-blockers from this review was compared to that of thiazide diuretics from our previous review ( Chen 2009 ) , second-line beta-blockers reduce systolic BP to the same extent as second-line thiazide diuretics , but reduce diastolic BP to a greater degree .
The different effect on diastolic BP means that beta-blockers have little or no effect on pulse pressure whereas thiazides cause a significant dose-related decrease in pulse pressure .
This difference in the pattern of BP lowering with beta-blockers as compared to thiazides might be the explanation for the fact that beta-blockers appear to be less effective at reducing adverse cardiovascular outcomes than thiazide diuretics , particularly in older individuals
BACKGROUND Beta-blockers are one of the more commonly prescribed classes of anti-hypertensive drugs , both as first-line and second-line .
OBJECTIVES To quantify the effect on systolic blood pressure ( SBP ) , diastolic blood pressure ( DBP ) , heart rate and withdrawals due to adverse effects of beta-blocker therapy when given as a second-line drug in adult patients with primary hypertension .