Age and responses to isometric exercise in hypertension: possible predictors of the antihypertensive effect of diuretics and beta-blockers.
In a multicenter, randomized, double-blind study, 108 hypertensive patients were treated with either chlorthalidone 25 mg or slow-release metoprolol 200 mg both given once daily over 4 weeks. Blood pressure and heart rate at rest and at the peak of an isometric exercise test (30% of maximal voluntary contraction for 3 min) were recorded at random and at the end of the study. Both treatments induced a significant (p less than 0.01) blood pressure reduction at rest and at the peak exercise, 50.0% of patients on chlorthalidone and 59.2% on metoprolol, respectively, having a lying diastolic blood pressure less than 95 mmHg. A weak but significant (p less than 0.001) positive correlation was found between age and change in systolic and diastolic blood pressure after chlorthalidone. Such a relationship was absent in the metoprolol group, where a significant (p less than 0.01) positive correlation was found between diastolic pressure rise from rest to the peak exercise at randomization, and the reduction in resting diastolic pressure at the end of the study. Treatments were well tolerated, only a decrease (p less than 0.05) in serum potassium (from 4.4 to 4.0 mEq/l) in the chlorthalidone group was observed. Results suggest that age may influence the antihypertensive response to chlorthalidone, while diastolic pressure rise in isometric exercise may predict the degree of pressure response to sustained beta-adrenergic blockade with metoprolol.
Corea
L
L
Valori
C
C
Bentivoglio
M
M
Verdecchia
P
P
Bichisao
E
E
D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use*; D000328:Adult; D000367:Age Factors; D000368:Aged; D000959:Antihypertensive Agents / Q000627:therapeutic use*; D001794:Blood Pressure / Q000187:drug effects; D002752:Chlorthalidone / Q000494:pharmacology; D004232:Diuretics / Q000627:therapeutic use*; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D006973:Hypertension / Q000188:drug therapy* / Q000503:physiopathology; D008297:Male; D008790:Metoprolol / Q000494:pharmacology; D008875:Middle Aged; D005082:Physical Exertion; D011897:Random Allocation
D000319:Adrenergic beta-Antagonists; D000959:Antihypertensive Agents; D004232:Diuretics; D008790:Metoprolol; D002752:Chlorthalidone