The Australian National Blood Pressure Study: a test of the effectiveness of antihypertensive therapy on the incidence of ischaemic heart disease.
Although hypertension is an acknowledged risk factor in ischaemic heart disease (IHD) the question remains whether antihypertensive therapy is necessarily beneficial. A priori, because coronary atherosclerosis is probably irreversible, the time for effective intervention would seem to be well before the development of clinical manifestations. The Australian National Blood Pressure Study, a long term clinical trial of the treatment of mild hypertension, is in principle better suited than previous trials to answer the question because the trial population selected (4000 subjects aged 30-69) contains substantial proportions of younger age groups (26% below 45) and of females (37%) and none had manifest IHD at entry. Sensitivity to the emergence of IHD in the trial population is increased by including as diagnostic indices angina and ischaemic ECG changes, using suitably objective methods, as well as myocardial infarction and sudden death. Thus morbidity and mortality from IHD which currently accounts for 71% of trial end points (cf 19% for stroke) will effectively determine the outcome of the trial. The occurrence of a substantial proportion of subjects withdrawn from randomised treatment will mean that the question will be answered necessarily in two ways: firstly in respect of those subjects remaining on their assigned treatments and secondly in terms of all subjects initially assigned one treatment or other irrespective of the subsequent need to change treatment on ethical grounds or of the degree of compliance.
D000328:Adult; D000368:Aged; D000959:Antihypertensive Agents / Q000627:therapeutic use*; D001315:Australia; D002986:Clinical Trials as Topic; D003327:Coronary Disease / Q000453:epidemiology / Q000401:mortality / Q000517:prevention & control*; D005260:Female; D006801:Humans; D006973:Hypertension / Q000188:drug therapy / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D010352:Patient Dropouts; D010919:Placebos
D000959:Antihypertensive Agents; D010919:Placebos