EFFECT OF LONG-ACTING AND SHORT-ACTING CALCIUM-ANTAGONISTS ON CARDIOVASCULAR OUTCOMES IN HYPERTENSIVE PATIENTS

Background Short-acting calcium antagonists may increase coronary arte ry morbidity, mortality, and non-cardiovascular complications in hyper tensive patients. We assessed whether this association was also true f or long-acting calcium antagonists. Methods We did a case-control stud y, which was nested within a systematic hypertension control programme for a prospective cohort of 4350 people (first seen 1981-94). Cases ( n=189) were hypertensive patients who had had a first cardiovascular e vent, including all cardiovascular deaths and hospitalisations, betwee n 1989 and 1995. Controls (n=189) were individually matched to cases f or sex, ethnic origin, age, type of previous antihypertensive treatmen t, year of entry into the study, and length of follow-up. We collected data on any prescribed drug regimen that was being taken on the event date for cases and on the same date for matched controls. Calcium ant agonists were classified by duration of action. Findings Compared with those on beta-blocker monotherapy, patients on long-acting calcium an tagonists (n=136) had no increased risk of a cardiovascular event (adj usted odds ratio 0.76 [95% CI 0.41-1.43]), whereas patients on short-a cting calcium antagonists (n=27) were at significantly greater risk (a djusted odds ratio 3.88 [1.15-13.11], p=0.029). Among 38 matched pairs who were both on calcium antagonists, the adjusted risk ratio for sho rt-acting versus long-acting was 8.56 (1.88-38.97), p<0.01. Interpreta tion Long-acting and short-acting calcium antagonists differ in cardio vascular outcomes. Consistent with earlier findings, the use of short- acting calcium antagonists was associated with increased risk of a car diovascular event. This finding highlights the need to complete on-goi ng clinical trials so that the relative cardiovascular impact of vario us antihypertensive agents can be assessed.