New research published today in the Journal of the American Medical Association indicates that current EU guidelines on how and when to lower blood pressure for diabetes patients could increase the risk of stroke and diabetic eye disease.
In one of the most comprehensive systematic reviews of research in this area, researchers from The George Institute for Global Health, affiliated with the Oxford Martin School at Oxford University, are challenging recent changes to US and European guidelines that have relaxed previous recommendations of lower blood pressure targets in people with diabetes.
Globally, it is estimated that about 400 million people have diabetes, putting them at high risk of heart disease, stroke, kidney disease and eye disease. In the UK, where about 2.5 million people have the condition, diabetes is a leading cause of kidney disease and blindness.
Most guidelines around the world recommended that people with diabetes have their blood pressure reduced to below 130/80 mmHg, which is lower than the target of 140/90 mmHg generally recommended for people without diabetes. Last year influential guidelines in the US and Europe controversially relaxed the threshold for initiation of BP-lowering treatment from 130mm Hg to 140mm Hg in diabetes patients.
Urging for guidelines around the world to reflect the new findings, author Professor Kazem Rahimi of the George Institute United Kingdom and the University of Oxford said this research provides fundamental evidence about how blood pressure should be treated in people with diabetes.
He said: “Our review shows that people with diabetes who reached a systolic blood pressure below 130mmHg had about a 25% lower stroke risk compared with those with higher blood pressure levels. Our analyses indicate that lower blood pressure reduces risk of diabetic eye disease and early kidney disease too.”
“Unfortunately, recent US and EU changes to the guidelines will negatively impact the treatment options for people with diabetes in the UK. We urgently call for these recent changes to guidelines to be modified and for all guidelines around the world to consistently reflect the evidence, so that patients with diabetes can receive the best possible treatment.
"When considering blood pressure targets in these patients, it is critical to make an individualised assessment of the balance between the benefits of more intensive treatment and any adverse effects of increasing medication,” says co-author of the paper and Chief Scientist of The George Institute for Global Health, Professor Anushka Patel. “This research indicates that many people with diabetes may have net benefits with more aggressive treatment.”
Blood pressure and diabetes expert, Professor Neil Poulter from Imperial College London said the increasing prevalence of diabetes globally and across Europe is an “unfolding nightmare” and that treatment recommendations need to reflect the best available evidence.
Professor Poulter, who was not involved in the study, said he was very pleased the review had been carried out. “I expect this study to influence guidelines for the treatment of people with diabetes, and for this to translate to appreciable effects on the health of people with diabetes.”
“I have been increasingly concerned about the trend to advocate higher blood pressure targets as reflected by recent changes to guidelines in Europe and the US; this study provides the evidence needed to reconsider this.”