Guidelines for High Blood Pressure and Diabetes
Two new publications bring into question the American Diabetes Association (ADA) recommendation that blood pressures should be less than 130/80 in people with type 2 diabetes. What does this mean for diabetics who also have high blood pressure?
New ACCORD study shows intensive treatment no better than standard treatment
On March 14, the ACCORD Study Group released an online publication in the New England Journal of Medicine describing the results of their study entitled, “The effects of intensive blood-pressure control in type 2 diabetes.
” They randomly assigned 4,733 participants with type 2 diabetes either to intensive therapy, aimed at a systolic pressure of less than 120, or to standard therapy, with a systolic pressure of less than 140 as the target. Participants were followed for an average of 4.7 years. The results: the incidence of fatal and nonfatal major cardiovascular events was not reduced by intensive therapy compared with standard therapy. In addition the number of serious adverse events was almost three times greater in the intensive treatment participants than in those getting standard therapy.
Similar results for the INVEST study
Although its design was different, results of the INVEST study were similar. This study assigned 6,400 patients with diabetes and coronary artery disease to achieve a systolic blood pressure less than 130 and a diastolic pressure less than 85. Results: Those who attained tight blood pressure control (systolic pressure less than 130) were no more successful in avoiding heart attacks, stokes, or death than those with usual blood pressure control (systolic pressures between 130 and 140). And all-cause mortality increased in those whose systolic blood pressure was lowered to less than 115. Given this, the authors concluded that there was no benefit to lowering systolic blood pressure below 130 compared to lowering it to between 130 and 140.
What does this mean?
Taken together, these findings strongly suggest that the ADA should reexamine its blood pressure guidelines for those with diabetes. The higher doses of initial medications or the additional ones that are generally needed to reduce systolic pressure below 130 add more costs and increase the risk of side effects.
Earlier studies have clearly demonstrated the cardiovascular benefits of controlling high blood pressures in patients with diabetes. And during the follow-up period of the INVEST trial, people whose systolic pressure remained greater than 140 had nearly a 50 percent greater number of strokes, heart attacks, and deaths than those whose pressure was reduced to between 130 and 140.
It is critical, therefore, that people with diabetes and their doctors do not misinterpret the results of these studies. If you have diabetes, you should continue efforts to lower elevated blood pressures, probably with a target systolic pressure below 140, but not to the previous targeted levels of lower than 130.
By Simeon Margolis, M.D., Ph.D.