The Multicenter Isradipine/Diuretic Atherosclerosis Study

Abstract

Hypertension is a risk factor for the development of atherosclerosis and its complications, which are among the major causes of morbidity and mortality. Although recent clinical trials indicate that antihypertensive treatment reduces morbidity and mortality associated with stroke, congestive heart failure, and renal insufficiency, questions remain as to whether such treatment also prevents coronary heart disease (CHD) mortality. The observed reduction in CHD mortality from pooled clinical trial data was 10–14% and was much less than the expected 20–25%, reduction for a 5–6 mm Hg reduction in diastolic pressure. One explanation may he that subtle adverse metabolic effects of treatment may have blunted the beneficial effects. Isradipine, a dihydropyridine calcium antagonist, is a potent antihypertensive drug with antiatherogenic properties in animal models. Therefore, we hypothesized that isradipine may he appropriate for testing the efficacy of antihypertensive treatment in retarding the progression of atherosclerosis in humans. The Multicenter Isradipine/Diuretic Atherosclerosis Study (MIDAS) is a clinical trial designed to compare the efficacy of isradipine (2.5 or 5 mg b.i.d.) with hydrochlorothiazide (12.5 or 25 mg b.i.d.) in retarding the progression of early carotid atherosclerosis as monitored by high-resolution B-mode ultrasonography.