Navigation Links
Too-Low Blood Pressure Can Also Bring Danger

What's OK for the kidney and brain may not be best for the heart, expert says

THURSDAY, May 7 (HealthDay News) -- While too-high blood pressure is a clear hazard for most people, too-low pressure can apparently be a threat in some cases as well.

A new study of 10,001 people with coronary artery disease found what statisticians call a J-shaped curve of mortality, meaning a higher death rate for people with the lowest blood pressure. Dr. Franz H. Messerli, a professor of clinical medicine at Columbia University Medical Center and director of the hypertension program at St. Luke's-Roosevelt Hospital in New York City, reported on the finding Thursday at the American Society of Hypertension meeting in San Francisco.

"It stands to reason that there has to be a J-shaped curve," Messerli said. "If your blood pressure were zero, you would be dead."

He acknowledged that the people in the study were a bit out of the ordinary, with already-diagnosed coronary artery disease. The study was aimed at determining the effect of treatment with different amounts of a cholesterol-lowering statin drug, with blood pressure measured as a matter of routine.

When the results were in, the lowest rate of deaths and major coronary problems such as heart disease was seen not in the participants with the lowest blood pressure but in those slightly to the right on the curve, with a reading of 139.9 for systolic pressure (the reading when the heart contracts) and 79.2 for diastolic pressure.

Though Messerli stressed that this was "a unique population, with coronary artery disease, where the coronary arteries are compromised," he noted that "there has to be a point where lowering blood pressure is counterproductive."

That point can be seen on the curve of systolic pressure in this group, he said. "When you go from 120 to 130, even from 110 to 130, there is very little difference," Messerli said. "When it goes below 110, then all of a sudden it becomes very obvious."

The effect is more pronounced for diastolic pressure readings. "If you go to 70 or below, say to 60, there is a fourfold higher risk in the primary outcomes," he said.

A too-low reading, he noted, could mean that the brain is not getting enough blood. "Obviously, if there is a lack of blood, there can be danger similar to that when there is too much blood," Messerli said.

The finding in this particular group certainly doesn't mean that most people should worry about blood pressure being too low, he said. "By and large, within reason, lower is better," Messerli said.

But that might not be true in special cases, he said. "You can have a funny situation where one organ in the body is demanding more blood than is good for the rest of the body," Messerli said. "What is OK for the kidney and OK for the brain may not be OK for the heart."

Controlling high blood pressure remains a major concern for physicians, Messerli said. "There are a lot of patients who are untreated and uncontrolled," he said. "We need to do a better job."

Dr. Alan H. Gradman, professor of medicine at Temple University, said that the study should be treated with caution because the number of people with very low blood pressure was small, but he said that "it does suggest that there may well be a J curve in people with coronary artery disease."

Though many other studies have not shown a J curve, "which is why the idea that you can't go too low is out there," the new study results might mean a slight revision of that rule in some cases, Gradman said.

"If you treat people with coronary artery disease for hypertension, you don't want to go too low, to diastolic pressure below about 70," he said. "That's the take-home message here."

More information

The U.S. National Heart, Lung and Blood Institute has more on high blood pressure.

SOURCES: Franz H. Messerli, M.D., professor, clinical medicine, Columbia University Medical Center, and director, hypertension program, St. Luke's-Roosevelt Hospital, New York City; Alan H. Gradman, M.D., professor, medicine, Temple University, Philadelphia; May 7, 2009, meeting, American Society of Hypertension, San Francisco

Copyright©2009 ScoutNews,LLC.
All rights reserved  

Related medicine news :

1. Specific antagonism lowers blood pressure
2. Restricting Blood Flow May Help Heart Bypass Patients
3. FDA Updates Prescription Guidelines for Blood Thinner
4. Doctors Often Miss High Blood Pressure in Kids
5. Back to School Means Return of School Blood Drives
6. Blood-flow detector software show promise in preventing brain damage
7. FDA Approves New Roche West Nile Virus Blood Screening Test
8. Australian-led international study shows blood pressure drugs cut death rate in type 2 diabetes
9. Laser blasts viruses in blood
10. Study Demonstrates Marteks Algal DHA Oil Improves Blood Triglyceride Lipid Levels
11. LifeMasters Provides Tips for Maintaining a Healthy Blood Cholesterol Level
Post Your Comments:
Related Image:
Too-Low Blood Pressure Can Also Bring Danger
(Date:11/29/2015)... San Jose, CA (PRWEB) , ... November 29, 2015 , ... ... Bay Area, is proud to announce their December, 2015, featured apartment community: Epic. In ... looking for corporate housing in the tight Bay Area rental market to efficiently find ...
(Date:11/28/2015)... ... 2015 , ... Safe storage for contraceptive devices may not always be easy ... Jersey and the other from Bradley Beach, New Jersey, there is an easy solution ... having to replace NuvaRings more often than necessary. As such, it affords peace of ...
(Date:11/28/2015)... ... , ... Beginning November 30th at 6:00 a.m. EST until 11:59 p.m. EST, ... of up to 20% off orders $80 or more to free gifts with purchases, there ... , As a competitive e-commerce website for skin care and cosmetic needs, customers will save ...
(Date:11/27/2015)... ... November 28, 2015 , ... There is only one major question facing ... last year? , This question has not been an easy question to answer. Especially ... age and the younger workforce don’t share the same discipline around working long hours. ...
(Date:11/27/2015)... ... November 27, 2015 , ... According to an article published ... Toronto and the University of British Columbia suggested that laws requiring bicyclists to wear ... explains that part of the reason for the controversial conclusion is that, while helmets ...
Breaking Medicine News(10 mins):
(Date:11/26/2015)... Nov. 26, 2015 Research and Markets ... the "2016 Future Horizons and Growth Strategies ... Supplier Shares, Country Segment Forecasts, Competitive Intelligence, Emerging ... --> --> This ... the Italian therapeutic drug monitoring market, including emerging ...
(Date:11/26/2015)... , November 26, 2015 ... the addition of the  "2016 Future ... European Cell Surface Marker Testing Market: ...  report to their offering.  --> ... addition of the  "2016 Future Horizons ...
(Date:11/25/2015)...  The total global healthcare industry is expected to grow ... Latin America has the highest projected growth at ... Japan ), is second with growth projected at 11.5%. ... healthcare expenditure. In 2013-2014, total government funded healthcare was nearly ... to 41.2% in 2013-2014. In real terms, out of pocket ...
Breaking Medicine Technology: