Effects of placebo, bisoprolol (10 mg q.d.), propranolol (80 mg b.i.d) and
metoprolol (100 mg b.i.d) on nocturnal decline in blood pressure were evalu
ated by 24-hour blood pressure monitoring in 14 inpatients with mild-to-mod
erate hypertension in a double blind crossover study. Compared with placebo
propranolol and bisoprolol produced significantly greater declines in noct
urnal diastolic blood pressure (8,9+/-0,6, 12,9+/-1,3 and 12,6+/-1,4%, resp
ectively). Propranolol caused greater than placebo decline in nocturnal sys
tolic blood pressure (12,0+/-1,2 and 8,0+/-0,6%, respectively). Metoprolol
did not affect these parameters. Average nocturnal blood pressure declines
on placebo were equal during 5 periods of monitoring. However pronounced sp
ontaneous fluctuations of individual values were noted. Thus in studies of
nocturnal blood pressure decline it is advisable to conduct repetitive 24-h
our blood pressure recordings both prior to and on treatment. Otherwise the
attitude to results should be cautious.