A Cochrane review says that aiming for lower than standard blood pressure targets offers no known clinical benefit. Researchers found that using antihypertensive drugs to reduce blood pressure below the 140/90 mm Hg standard did not lower death rates or serious morbidity.
"At present there is no evidence from randomized trials to support aiming for a blood pressure target lower than 140/90, in the general population of patients with elevated blood pressure," says lead researcher Jose Arguedas of the Faculty of Medicine at the University of Costa Rica in Costa Rica.
The findings do not support guidelines in a number of publications that recommend aiming for lower targets, based on the assumption that "lower is better" when it comes to blood pressure. The researchers were unable to determine whether it is safe to aim for lower targets because relevant data was missing from most of the trials.
The review is based on the results of seven trials, which together involved 22,089 people. Whilst patients aiming for targets below 135/85 mmHg did succeed in achieving greater reductions in blood pressure than those in the standard target group, there was no difference between the two groups in terms of the number of patients dying or suffering heart attacks, strokes, heart failure or kidney failure.
"Our research included patients with diabetes or chronic renal disease, and the evidence was slightly less robust for those subgroups of patients. We intend to carry out separate systematic reviews for those subgroups, especially because guidelines recommend even lower blood pressure targets for them", says Arguedas.