Meta-analysis suggests need for wider use of blood pressure-lowering drugs

by Bruce Sylvester: No matter what their blood pressure is at the beginning of treatment, blood pressure-lowering drugs should be offered to all persons at high risk of having a heart attack or stroke, researchers from a new meta-analysis of relevant trials reported on Dec. 23, 2015 in The Lancet.

“The benefits of blood pressure lowering treatment for prevention of cardiovascular disease are well established. However, the extent to which these effects differ by baseline blood pressure, presence of comorbidities, or drug class is less clear. We therefore performed a systematic review and meta-analysis to clarify these differences,” the authors said.

Professor Kazem Rahimi from The George Institute for Global Health at the University of Oxford in the UK and colleagues analysed data from large-scale randomized blood pressure target trials enacted from January 1966 to July 2015.

All randomized controlled trials of blood pressure lowering treatment were eligible if they had had a minimum of 1000 patient-years of follow-up in each study arm. No trials were excluded due to baseline comorbidities. Trials of antihypertensive drugs for use other than for hypertension were also eligible.

The investigators extracted data about study characteristics and the outcomes of major cardiovascular disease events, coronary heart disease, stroke, heart failure, renal failure, and all-cause mortality.

They identified 123 eligible studies with 613, 815 participants for the meta-analysis.

They reported that treatment with any of the main classes of blood pressure-lowering drugs significantly lowered the risk of major cardiovascular events, stroke, heart failure, and death proportional to the degree to which blood pressure was lowered. Every 10 mmHg reduction in systolic blood pressure lowered the risk of major cardiovascular disease events and heart disease by about one fifth, stroke and heart failure by about a quarter and death from any cause by 13%.

Notably, the reductions appeared across a range of high risk patients including those with a history of cardiovascular disease, heart failure, diabetes, and kidney disease, and irrespective of whether their blood pressure was already low (less than 130 mmHg) at baseline.

Professor Rahimi said, “Our findings clearly show that treating blood pressure to a lower level than currently recommended could greatly reduce the incidence of cardiovascular disease and potentially save millions of lives if the treatment was widely implemented. The results provide strong support for reducing systolic blood pressure to less than 130 mmHg, and blood pressure-lowering drugs should be offered to all patients at high risk of having a heart attack or stroke, whatever their reason for being at risk.”