Many people with diabetes also have high blood pressure. Clinical guidelines have suggested blood pressure levels in people with diabetes should be kept lower than the standard for people without diabetes. However, a new review from The Cochrane Library does not find support for this practice.
"It's been clinical practice to try to decrease blood pressure as much as possible in this group in order to reduce both mortality and morbidity," said Jose Agustin Arguedas, M.D., professor in the department of clinical pharmacology at the University of Costa Rica. Several frequently used clinical guidelines suggest that people with diabetes should have blood pressure less than 130 over 80, he said.
Lowering blood pressure typically means increasing the number or dosage of medications, which can be inconvenient and expensive for patients.
In the new review, the researchers studied five trials with a total of 7,314 participants to evaluate whether lower blood pressure targets (less than 130/85 mmHg) for people with diabetes were better than standard blood pressure targets. The review determined that setting blood pressure targets lower than 140 over 90 mmHg in people with diabetes did not lower the risk of heart attack, stroke or death.
"From a diabetes perspective, people with type 2 diabetes have issues other than just blood sugar that determines ultimate risk for complications," said John E. Anderson, M.D. president for science and medicine at the American Diabetes Association. "Patients with diabetes have increased risk of cardiovascular problems like stroke and heart attack and so treatment for blood sugar, blood pressure and cholesterol are of paramount importance. This Cochrane review correlates and conforms to our standards of care at ADA—that we should treat to target a goal of 140 over 80 or less."
For some populations, he said, even more aggressive blood pressure targeting might be appropriate if it can be done without undue burden of medication.
"Surprisingly perhaps, most people assumed it was a recognized fact that we should try to get blood pressure [as low as possible] in this population and therefore additional research wasn't needed," noted Arguedas. "We showed we need more research to really answer the question about how to treat high blood pressure in order to achieve the greatest benefit and the lowest risk for this population."
Arguedas JA, Leiva V, Wright JM. "Blood pressure targets for hypertension in people with diabetes mellitus." Cochrane Database of Systematic Reviews 2010, Issue 1. Art. No.: CD008277. DOI: 10.1002/14651858.CD008277.