title: Double-blind, parallel, comparative multicentre study of a new combination of diltiazem and hydrochlorothiazide with individual components in patients with mild or moderate hypertension.
abstract: OBJECTIVE
  To compare the antihypertensive efficacy and tolerability of a new combination preparation of diltiazem (150 mg) and hydrochlorothiazide (12.5 mg) with the individual constituents in patients with mild/moderate hypertension.
  
  
  METHODS
  Multi-centre, double-blind, randomised parallel group study.
  
  
  METHODS
  Seventy-one patients with essential hypertension were recruited to the study.
  
  
  METHODS
  Following completion of the placebo run-in period 63 patients fulfilled the prerandomisation criteria and entered the 10 week treatment period. Patients were randomised to receive either the combination preparation (D 150 mg/H 12.5 mg), diltiazem (150 mg) or hydrochlorthiazide (12.5 mg). The dosage was increased in three patients who had not attained target blood pressure (BP) control after 6 weeks.
  
  
  METHODS
  Response to treatment assessed by change from baseline in clinic and 24 h ambulatory BP.
  
  
  RESULTS
  The proportion of patients achieving target BP (a reduction in resting supine diastolic blood pressure (DBP) to below 90 mm Hg or a reduction of 10 mm Hg from baseline) was 80% in the combination group, 55% in the diltiazem group, and 38% in the hydrochlorothiazide group. The respective figures for reduction in supine DBP from baseline were 13.5 mm Hg, 11.2 mm Hg and 5.9 mm Hg. A similar treatment order appeared throughout each of the efficacy variables. BP control throughout the 24 h dosing interval was demonstrated by ambulatory BP monitoring. Each treatment was well tolerated.
  
  
  CONCLUSIONS
  This study provides clear evidence of the efficacy of combination therapy with diltiazem and hydrochlorothiazide in the management of patients with hypertension.
authors.affiliation: Cardiac Research Unit, Derbyshire Royal Infirmary, Derby, UK.
authors.forename: G
authors.initials: G
authors.lastname: Manning
authors.forename: A
authors.initials: A
authors.lastname: Joy
authors.forename: C J
authors.initials: CJ
authors.lastname: Mathias
authors.forename: C J
authors.initials: CJ
authors.lastname: McDonald
authors.forename: M W
authors.initials: MW
authors.lastname: Millar-Craig
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001794:Blood Pressure; D018660:Blood Pressure Monitoring, Ambulatory; D002121:Calcium Channel Blockers / Q000009:adverse effects / Q000627:therapeutic use*; D003971:Diastole; D004110:Diltiazem / Q000009:adverse effects / Q000627:therapeutic use*; D004232:Diuretics; D004311:Double-Blind Method; D004359:Drug Therapy, Combination; D006801:Humans; D006852:Hydrochlorothiazide / Q000009:adverse effects / Q000627:therapeutic use*; D006973:Hypertension / Q000188:drug therapy* / Q000503:physiopathology*; D008875:Middle Aged; D049993:Sodium Chloride Symporter Inhibitors / Q000009:adverse effects / Q000627:therapeutic use*; D016683:Supine Position; D013599:Systole
chemical_list: D002121:Calcium Channel Blockers; D004232:Diuretics; D049993:Sodium Chloride Symporter Inhibitors; D006852:Hydrochlorothiazide; D004110:Diltiazem