Retrospective longitudinal cohort study comparing the effects of angiotensin-converting enzyme inhibitors and long-acting calcium channel blockers on total and cardiovascular mortality in patients with hypertension.
BACKGROUND
There is controversy regarding the impact that different antihypertensive regimens, including modern combination therapy, have on the incidence of myocardial infarction, other cardiovascular events, and mortality.


OBJECTIVE
The objective of this study was to determine and compare the effects of treatment strategies based on angiotensin-converting enzyme (ACE) inhibitors and long-acting calcium channel blockers (CCBs) on total and cardiovascular mortality in hypertensive patients in a usual-care setting.


METHODS
This retrospective, longitudinal cohort study used integrated medical and pharmacy claims data from a geographically diverse administrative database of >8 million persons in the United States. Patients aged > or = 18 years with hypertension were eligible if they had filled a prescription for either an ACE inhibitor or a long-acting CCB between January 1, 1995, and June 30, 1999 (the index prescription). Patients who had a prescription for any antihypertensive agents before the index prescription were excluded, as were eligible ACE inhibitor-treated patients who used CCBs or CCB-treated patients who used ACE inhibitors during the follow-up period. Use of all other antihypertensive medications was permitted. Patients were matched using a propensity score generated from a logistic regression model. A survival-analysis approach was used to compare mortality between groups. The final cohorts were assessed through June 30, 2002.


RESULTS
A total of 18,199 patients met the study inclusion criteria; 12,608 (69.3%) used an ACE inhibitor and 5,591 (30.7%) used a CCB. The mean follow-up was approximately 4.4 years. After cohort matching using the propensity score, the study population consisted of 10,926 patients, 5,463 matched patients in each group. The adjusted hazard ratios (95% CIs) for all-cause, cardiovascular, congestive heart disease, and congestive heart failure mortality in the ACE-inhibitor group compared with the CCB group for the entire follow-up period were 0.70 (0.63-0.79), 0.65 (0.53-0.80), 0.47 (0.32-0.70), and 0.74 (0.49-1.12), respectively.


CONCLUSIONS
Analysis of a large medical and pharmacy database suggests that an ACE inhibitor-based treatment strategy is associated with reduced mortality compared with a CCB-based strategy in patients with hypertension in a managed care setting.
Tardif
Jean-Claude
JC
Montreal Heart Institute, Montreal H1T IC8, Canada. jean-claude.tardif@icm-mhi.org
Ducharme
Anique
A
Yu
Holly
H
Wogen
Jenifer
J
Guertin
Marie-Claude
MC
D000328:Adult; D000368:Aged; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000627:therapeutic use*; D002121:Calcium Channel Blockers / Q000627:therapeutic use*; D016208:Databases, Factual; D005260:Female; D006801:Humans; D006973:Hypertension / Q000188:drug therapy* / Q000453:epidemiology / Q000401:mortality; D015994:Incidence; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009204:Myocardial Revascularization; D012189:Retrospective Studies; D014481:United States / Q000453:epidemiology
D000806:Angiotensin-Converting Enzyme Inhibitors; D002121:Calcium Channel Blockers