"Good control of blood pressure is important for decreasing bad outcomes for patients (with diabetes), such as heart attacks and kidney disease," said Dr. Eve Kerr, the study's lead author from the Department of Veterans Affairs Ann Arbor Healthcare System and the University of Michigan.

Doctors have gotten very good at making sure everyone at risk gets treated with blood pressure medications, she added. But some patients who needed blood pressure medications to begin with might end up not needing them later on.

"Sometimes when blood pressure gets too low, it's okay to back off," Kerr told Reuters Health.

Her team examined the medical records of close to one million diabetes patients treated at VA medical centers and outpatient clinics.

The vast majority of patients age 18 to 75 -- 94 percent -- either had normal blood pressure or were getting high blood pressure treated according to guidelines.

That means most diabetic veterans are getting the help they need when it comes to high blood pressure monitoring and treatment. But although under-treating blood pressure may not have been a big problem in the VA group, over-treatment seemed to be at least as common, if not more so, the researchers found.

More than one-third of patients treated at the VA with a blood pressure below 130/65 mm Hg were on at least three blood pressure lowering drugs, or were having their drug regimen increased. That was equal to eight percent of all diabetic veterans.

High blood pressure is considered to be 140/90 mm Hg or higher, according to the National Institutes of Health.

Depending on the hospital, between three and 20 percent of diabetic veterans were possibly being over-treated with blood pressure medications, Kerr and her colleagues reported Monday in the Archives of Internal Medicine.

Not only might those drugs be unnecessary, but they could cause problems for patients as well, researchers said.

"You don't want to put patients on medications unnecessarily, because there's risks with any medication -- whether it's a nuisance risk of a dry mouth or it could be potentially more serious, like making your blood pressure too low and having you more at risk for falls," said Eileen Handberg, a cardiology researcher from the University of Florida in Gainesville.

"You don't want to treat someone's blood pressure to the point that they're weak and dizzy because their blood pressure is too low," Handberg, who wrote a commentary published with the study, told Reuters Health.

She said guidelines don't currently set a lower limit for recommended blood pressure in diabetic patients -- and because of that, it's hard to say doctors in this study were doing anything wrong when they prescribed more blood pressure lowering drugs to people who might not have needed them.

Still, Handberg added, "There is a lot of conversation about, maybe lower isn't always better."

One limitation of the new study is that it can't show whether patients were actually harmed by their blood pressure getting too low, said Dr. Franz Messerli, director of the high blood pressure program at St. Luke's-Roosevelt Hospital in New York.

"We don't know whether over-treatment or under-treatment increased heart attack, stroke or death, and that's obviously the important issue," Messerli, who wasn't involved in the research, told Reuters Health.

Kerr said the new study can help inform future guideline-makers about how diabetic patients are currently being treated -- and how often too much blood pressure treatment might be a concern.

Researchers agreed that patients who find their blood pressure numbers dropping very low or who have side effects such as dizziness should talk with their doctors about their blood pressure and the possibility they can ease off aggressive treatment.

SOURCE: bit.ly/LPkvZ8 Archives of Internal Medicine, online May 28, 2012.

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