For some patients with type 2 diabetes, intense blood-pressure-lowering medication may do more harm than good, according to a new study published in the BMJ.
Antihypertensive medication may raise the risk of cardiovascular death for some people with type 2 diabetes, Medical News Today reports.
Mattias Brunström and Bo Carlberg of the Department of Public Health and Clinical Medicine at Umeå University in Sweden found that blood pressure drugs may increase the risk of cardiovascular death for diabetes patients with a systolic blood pressure under 140 mm/Hg. About two in three Americans with diabetes have high blood pressure, putting them at higher risk of stroke, heart disease, and other cardiovascular problems.
People with diabetes are often prescribed medication to help lower blood pressure. The American Diabetes Association recommends a systolic blood pressure target of less than 140 mm/Hg for patients with type 2 diabetes—the most common form of diabetes. A target of less than 130 mm/Hg is recommended for some patients, if that level can be achieved safely, according to Medical News Today.
In their study, Brunström and Carlberg investigated whether the effects of antihypertensive medication vary depending on a patient’s blood pressure prior to treatment. They conducted a meta-analysis of 49 randomized controlled trials that looked at the cardiovascular outcomes of people with diabetes who were receiving medication to lower blood pressure. The trials involved a total of 73,738 participants, the majority of whom had type 2 diabetes. Subjects were followed-up for at least 12 months.
The researchers found that study participants whose blood pressure was higher than 140 mm/Hg before treatment had a reduced risk of stroke, heart attack, heart failure, and all-cause mortality. But for subjects whose blood pressure was less than 140 mm/Hg prior to treatment, however, no cardiovascular benefits were identified. In fact, the researchers found that those participants were at greater risk of cardiovascular death, Medical News Today reports.
Brunström says the “study shows that intensive blood pressure-lowering treatment using antihypertensive drugs may be harmful for people with diabetes and a systolic blood pressure less than 140 mm/Hg.”
The researchers say their results may not apply to people with type 1 diabetes or those with diabetes who have normal blood pressure. They also point out that blood pressure medication is crucial to most people with diabetes who have systolic blood pressure above 140 mm/Hg. “[U]ndertreatment of high blood pressure is a bigger problem than overtreatment,” Brunström says.
The authors say the findings could have important implications for clinical guidelines for diabetes patients with high blood pressure, noting that many countries are due to review such guidelines in the next few years, Medical News Today reports. There has been discussion about recommending even lower blood pressure levels for people with diabetes, possibly as low as 130. Brunström says, “We are hoping that our study, which shows potential risks of such aggressive blood pressure-lowering treatment, will come to influence these guidelines.”