THE USE OF SELF-MEASURED BLOOD-PRESSURE DETERMINATIONS IN ASSESSING DYNAMICS OF DRUG COMPLIANCE IN A STUDY WITH AMLODIPINE ONCE-A-DAY, MORNING VERSUS EVENING
T. Mengden et al., THE USE OF SELF-MEASURED BLOOD-PRESSURE DETERMINATIONS IN ASSESSING DYNAMICS OF DRUG COMPLIANCE IN A STUDY WITH AMLODIPINE ONCE-A-DAY, MORNING VERSUS EVENING, Journal of hypertension, 11(12), 1993, pp. 1403-1411
Objective: To test whether the time of administration influences the t
herapeutic response to a calcium antagonist taken once a day. Also, th
e dynamics of drug compliance and its impact on blood pressure control
were investigated. Design: Twenty outpatients with mild-to-moderate h
ypertension were included in a randomized, placebo-controlled open stu
dy. In a crossover design, all of the patients received 5 mg amlodipin
e, either in the morning or in the evening, during two consecutive 4-w
eek treatment periods. Methods: Blood pressure was taken by casual mea
surement, ambulatory 24-h monitoring (SpaceLabs 90202) and self-measur
ement at home, performed with a semi-automatic oscillometric device du
ring the whole study period. Compliance was assessed using the Medicat
ion-Event-Monitoring System (MEMS). Results: Neither casual nor ambula
tory day- or night-time readings detected a significant difference bet
ween morning and evening administration. However, self-measurement doc
umented significantly greater blood pressure reductions for morning th
an for evening administration. The MEMS showed different compliance on
the days of ambulatory monitoring (100% with both drug regimens) comp
ared with the whole treatment period. The number of days with missed m
edication was thus significantly higher for the evening dosing regimen
. The difference in self-measured blood pressure between the two regim
ens was lost if the days with missed medication were removed from the
statistical analysis. Conclusions: Time of once-a-day amlodipine admin
istration does not influence its efficacy for 24-h blood pressure cont
rol. Furthermore, the use of self-measurement and the MEMS may provide
useful additional information on the pharmacodynamic impact of differ
ent dosing patterns in hypertensive patients.