Related Experiment Videos
Blood pressure J-curve: is it cause or effect?
1Albert Einstein College of Medicine, Department of Epidemiology and Social Medicine, Bronx, New York 10461, USA.
Insights
Antihypertensive therapy effectively prevents stroke but shows less reduction in coronary artery disease events than expected. A J-shaped curve links diastolic pressure to coronary events, suggesting caution in lowering pressure too much.
Area of Science:
- Cardiology
- Hypertension Research
- Clinical Trials
Background:
- Antihypertensive therapy is proven effective for stroke prevention, aligning with epidemiological predictions.
- However, the observed reduction in coronary artery disease (CAD) events is significantly lower than anticipated.
- Several hypotheses attempt to explain this discrepancy in CAD event reduction.
Purpose of the Study:
- To investigate the reasons for the shortfall in coronary artery disease event reduction with antihypertensive therapy.
- To examine the proposed link between excessive diastolic pressure reduction and increased myocardial infarction risk.
- To clarify the nature of the J-shaped association between diastolic pressure and coronary events.
Main Methods:
- Analysis of data from multiple clinical trials on antihypertensive therapy.
- Examination of the relationship between diastolic blood pressure levels and coronary events.
- Review of existing studies suggesting a J-shaped association and its potential causality.
Main Results:
- Clinical trials consistently show a J-shaped association between diastolic pressure and coronary events.
- This J-shaped phenomenon may be specific to patients with pre-existing coronary disease.
- The J-phenomenon might be a consequence, not a cause, of aortic atherosclerotic disease.
Conclusions:
- Physicians should aim for a moderate reduction in diastolic blood pressure.
- Target diastolic pressure should be maintained above 80 mmHg to mitigate potential risks.
- Further prospective studies are needed to definitively resolve the causality of the J-shaped association.
Abstract:
Clinical trials have demonstrated that antihypertensive therapy leads to the prevention of stroke, consistent with that predicted by epidemiological data. In contrast, in the same studies, the reduction in coronary artery disease events has been substantially less than predicted. Many possible explanations have been proposed to account for this shortfall in the reduction of disease produced by antihypertensive therapy. One suggestion has been that too great a fall in diastolic pressure during treatment actually increases the risk of myocardial infarction. A substantial body of data taken from clinical trials has consistently demonstrated a J-shaped association of diastolic pressure and coronary events. Some studies suggest that this J-shaped association is limited to those with coronary disease, and that the J-phenomenon is the result rather than the cause of atherosclerotic disease of the aorta. A prospective study is underway to resolve this issue. Meanwhile, the cautious physician is advised to seek a moderate decline in diastolic pressure to a level greater than 80 mmHg.