Effects of lowering diastolic blood pressure to <80 mmHg on cardiovascular mortality and events in patients with coronary artery disease: a systematic review and meta-analysis

The target of diastolic blood pressure (DBP) remains controversial in patients with coronary artery disease (CAD). We systematically searched PubMed/Medline and the Cochrane Central database for randomized controlled trials (RCTs) assessing the efficacy and safety of reducing DBP in CAD patients from January 1965 to July 2017. Seven placebo-controlled RCTs enrolling 34,814 CAD patients who achieved DBP <80 mmHg were included in the drug-intervention group. The average achieved blood pressures (BPs) were 126.3/75.1 and 131.5/77.8 mmHg in the drug-intervention and placebo-control groups, respectively. Drug intervention was associated with an 11% reduction in coronary revascularization and a 31% reduction in heart failure. In the drug-intervention group, all-cause death, myocardial infarction, angina pectoris, and stroke were reduced with marginal significance, whereas hypotension was increased by 123%. A meta-analysis of four RCTs, in which the achieved DBP was <75 mmHg, showed that the drug intervention was associated with a 22% reduction in heart failure. These results suggest that reducing DBP to 80 mmHg or less would significantly reduce coronary revascularization and heart failure but at the expense of causing hypotension in CAD patients. Further trials are warranted to prove this issue.