The use of confidence intervals to describe the precision of trough/peak ratios for diltiazem CD in the treatment of hypertension.
Once-daily diltiazem hydrochloride, CARDIZEM CD (diltiazem CD) 300 mg, was evaluated for safety, efficacy, and the relationship between peak and trough antihypertensive effects in a multicenter, placebo-controlled, parallel design trial. After a 4- to 6-week placebo baseline period, 111 patients with essential hypertension were randomized to receive placebo or diltiazem CD for a 4-week treatment period. Diltiazem CD 300 mg lowered supine diastolic and systolic blood pressure at trough significantly more than placebo (-7.5 mm Hg vs. -1.3 mm Hg, P = 0.0001 and -6.4 mm Hg vs. 0.5 mm Hg, P = 0.0051, respectively). Supine blood pressure was also measured hourly from 6 to 10 hours after the dose to assess peak effect and trough/peak ratios. Using the largest residual drug effect of -8.3 mm Hg at 6 hours as peak and the 24-hour residual drug effect of -5.9 mm Hg as trough, the trough/peak ratio was estimated to be 71%, with a lower one-sided 95% confidence limit of 50%. The precision of the trough/peak ratio is estimated by the lower confidence limit of 50%, which establishes the trough/peak ratio as statistically > or = 50%. No statistically significant differences in supine DBP were noted between the peak effect hours, indicating a plateau of the peak antihypertensive effect from 6 to 10 hours postdose. Diltiazem CD therapy was well tolerated, with no serious treatment-related adverse events reported during the trial and no patients discontinuing the trial due to a treatment-related adverse event.(ABSTRACT TRUNCATED AT 250 WORDS)
Meeves
S G
SG
Department of Clinical Research, Marion Merrell Dow Inc., Kansas City, Missouri 64134-0627.
Park
G D
GD
D000328:Adult; D001794:Blood Pressure / Q000187:drug effects*; D016001:Confidence Intervals; D004110:Diltiazem / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D006973:Hypertension / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged
D004110:Diltiazem