Despite the guidelines, lower blood pressure might be unhealthy for kidney patients

Jun 24, 2010

Recent guidelines by The National Kidney Foundation Disease Outcomes Quality Initiative (NKF KDOQI)1 call for lower target blood pressure levels in patients with chronic kidney disease (CKD). But in the absence of high-quality scientific evidence, there's a chance this recommendation could do more harm than good, according to a special article appearing in an upcoming issue of the Journal of the American Society Nephrology (JASN).

"The new goals are not definitively supported by data, would be costly to the healthcare system and potentially harmful to patients," according to Julia B. Lewis, MD (Vanderbilt University, Nashville, TN), who performed a critical review of the research evidence.

Issued last year, updated national guidelines for CKD treatment call for a target level of less than 130/80 mm Hg (millimeters of mercury) to help preserve . The recommendation was based on observational studies showing "a continuous benefit of reducing blood pressure to lower and lower levels."

However, Lewis points out several problems with the research behind the new guidelines. Most importantly, since patients in the observational studies were not randomly assigned to different blood pressure goals, the apparent benefit of lower blood pressures could result from other "confounding" factors. "The data supporting the current blood pressure guidelines for patients with CKD do not meet the standard of a primary outcome of a randomized trial," says Lewis.

She explains that, as kidney disease worsens, blood pressure rises and becomes harder to control. So the data may simply reflect the fact that patients with less severe kidney disease have lower blood pressure. In studies where patients were randomly assigned to treatments, the benefits of lower blood pressure were seen only in a subgroup of patients, or several years after the end of treatment.

"Also there is other evidence to bring into question the widespread application of this costly goal of a blood pressure less than 130/80 mm Hg," Lewis adds. Some studies have even suggested that CKD patients with very low blood pressure could be at increased risk of death.

A new trial sponsored by the National Institutes of Health (NIH) will compare the effects of different blood pressure targets in over 10,000 patients with CKD. Until the results are available, Lewis believes that doctors should make individualized decisions about blood pressure control for their patients with kidney disease.

Lewis emphasizes that no firm conclusions can be drawn from her review, since it was based on different types of studies with conflicting results.

Explore further: Nigeria death shows Ebola can spread by air travel

More information: The article, entitled "Blood Pressure Control in Chronic Kidney Disease: Is Less Really More?" will appear online at doi:10.1681/ASN.2010030236

add to favorites email to friend print save as pdf

Related Stories

Blood pressure targets: Aiming lower offers no benefit

Jul 08, 2009

Aiming for lower than standard blood pressure targets offers no known clinical benefit, according to a Cochrane Review. In a systematic review of the evidence, researchers found that using antihypertensive drugs to reduce ...

Recommended for you

Nigeria death shows Ebola can spread by air travel

10 hours ago

(AP)—Nigerian health authorities raced to stop the spread of Ebola on Saturday after a man sick with one of the world's deadliest diseases brought it by plane to Lagos, Africa's largest city with 21 million ...

Trial in salmonella outbreak to start in Georgia

10 hours ago

(AP)—Three people accused of scheming to manufacture and ship salmonella-tainted peanuts that killed nine people and sickened more than 700 are set to go to trial this week in Georgia.

Remote tribe members enter another village, catch flu

18 hours ago

Advocates for indigenous tribes are worried over incidents last month when some members of one of the last uncontacted tribes in the Peru/Brazil region, across borders, left their home in Peru and entered ...

Nigeria on red alert after first Ebola death

Jul 26, 2014

Nigeria was on alert against the possible spread of Ebola on Saturday, a day after the first confirmed death from the virus in Lagos, Africa's biggest city and the country's financial capital.

User comments : 0