LISINOPRIL IN THE TREATMENT OF HYPERTENSION - A CANADIAN POSTMARKETING SURVEILLANCE STUDY

A postmarketing surveillance study in 2273 Canadian office practices p rovided the largest body of clinical experience to date with the angio tensin-converting enzyme (ACE) inhibitor lisinopril in the treatment o f mild to moderate essential hypertension. The principal emphasis in t his uncontrolled study was safety, assessed in 10,289 patients. Patien ts with a diastolic blood pressure >90 mmHg were considered for the st udy. Both previously untreated patients and those who were experiencin g adverse effects from their current antihypertensive regimen were inc luded. Lisinopril was begun at a dose of 10 mg/day. Subsequent dose ad justments, to a maximum of 40 mg/day, were made to achieve optimal blo od pressure control (diastolic blood pressure less-than-or-equal-to 90 mmHg or greater-than-or-equal-to 10 mmHg below baseline for greater-t han-or-equal-to 4 weeks at the same dose). Therapy was continued for a minimum of 4 weeks to a maximum of 12 weeks, with patients examined e very 2 weeks. The frequencies of adverse effects and laboratory abnorm alities were analyzed in all treated patients. All 10,289 patients enr olled were considered in the analysis of safety. One or more adverse e ffects were reported for 1593 (15.5%) patients, and 802 (7.8%) withdre w from the study because of adverse effects. The most frequent adverse effects were cough (4.0%), dizziness (2.3%), headache (2.1%), astheni a (1.7%), and nausea (1.0%). The physicians' global assessment rated o verall tolerability as very good or good for 77.1% of the patients. An tihypertensive effect was evaluated in 5886 patients who met the crite ria for efficacy analysis. The criterion response was attained in 5141 (87.3%) patients, with 68.6% responding to 10 mg/day of lisinopril, 2 6.3% to 20 mg/day, and 3.2% to 40 mg/day (the other 1.9% responded at nonstandard doses). Lisinopril was safe and well-tolerated. Except for cough, class effects of ACE inhibitors were rarely encountered. The r esults of the efficacy analysis confirm the established efficacy of li sinopril in patients with mild to moderate essential hypertension.