Effects of antihypertensive single-drug therapy on heart rate

Heart rate increasingly is being recognized either as an independent risk factor for a wide variety of cardiovascular disorders or as a surrogate marker for them. We analyzed the changes in heart rate associated with antihypertensive therapy with six drugs and placebo from the VA Cooperative Study on Single-Drug Therapy. These results were published previously (American Journal of Hypertension 1998;11:597-601). This paper provides a summary of the earlier publication with the addition of three figures not previously published. Atenolol had the greatest effect on heart rate reduction, followed by clonidine and diltiazem-SR. Hydrochlorothiazide and captopril were associated with small reductions in heart rate over time, whereas prazosin increased heart rate. Patients whose blood pressure was controlled by placebo had a 3.1 beats/min reduction of heart rate at 2 years. When the baseline heart rate was 65 beats/min or less, all drugs increased the heart rate except for atenolol, which further reduced it. Although it is clear that each of the six drugs used in our study had a different effect on heart rate, we cannot state that drug-induced reduction in heart rate per se confers a decrease in cardiovascular risk.