Antihypertensive efficacy of night-time graded-release diltiazem versus morning amlodipine in African Americans.
BACKGROUND
The effect of a once daily night-time (10 pm) graded-release diltiazem (GRD) on early morning blood pressure (BP), heart rate (HR), and rate-pressure product (RPP) were compared with the effect of morning (8 am) amlodipine in 262 African American individuals with hypertension.


METHODS
The multicenter, randomized, double-blind, parallel-group, dose-to-effect trial evaluated changes from baseline in BP, HR, and RPP (HR x systolic BP) by ambulatory BP monitoring during the first 4 h after awakening (diastolic BP = primary), between 6 am and 12 noon, and over a 24-h period. Patients were randomized to night-time GRD 360 mg (n = 132) or morning amlodipine 5 mg (n = 130) for 6 weeks, and were titrated to GRD 540 mg or amlodipine 10 mg after 6 weeks if clinic systolic BP/diastolic BP (SBP/DBP) was > or = 130/85 mm Hg.


RESULTS
Compared with amlodipine, GRD showed significantly greater DBP reductions of 3.5 mm Hg (P < .0049) and 3.2 mm Hg (P < .0019) during the first 4 h after awakening and between 6 am and 12 noon respectively, as well as comparable reduction for the 24-h mean DBP. The SBP reductions during the morning periods were comparable, but the reduction in the 24-h mean SBP was 3.4 mm Hg greater (P < .0022) for amlodipine. Mean reductions in HR and RPP were significantly greater (P < or = .0008) for GRD during all intervals; amlodipine increased whereas diltiazem reduced HR with mean differences of 6.7 to 9.3 beats/min. Both treatments were well tolerated.


CONCLUSIONS
Night-time GRD was more effective than morning amlodipine in reducing early morning DBP, HR, and RPP, as well as 24-h HR and RPP in African American individuals with hypertension. Amlodipine was more effective in reducing SBP over the 24-h period.
Wright
Jackson T
JT
Department of Medicine, Division of Hypertension, Case Western Reserve University, Cleveland, Ohio, USA. jxw20@po.cwru.edu
Sica
Domenic A
DA
Gana
Theophilus J
TJ
Bohannon
Kathryn
K
Pascual
Luz G
LG
Albert
Kenneth S
KS
D000293:Adolescent; D000328:Adult; D001741:Black or African American; D000368:Aged; D017311:Amlodipine / Q000008:administration & dosage* / Q000009:adverse effects; D000959:Antihypertensive Agents / Q000008:administration & dosage* / Q000009:adverse effects; D001794:Blood Pressure / Q000187:drug effects; D002940:Circadian Rhythm; D003692:Delayed-Action Preparations; D004110:Diltiazem / Q000008:administration & dosage* / Q000009:adverse effects; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D006973:Hypertension / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D016896:Treatment Outcome
D000959:Antihypertensive Agents; D003692:Delayed-Action Preparations; D017311:Amlodipine; D004110:Diltiazem