Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Mayo Clinic finds effective remedy for blood pressure drop when standing up

05.10.2004


Mayo Clinic neurologists have discovered a drug application smart enough to alleviate orthostatic hypotension -- problems with sinking blood pressure when standing up from a sitting position -- without the unwanted effect of also causing patients’ blood pressure to soar when lying down.



"This is a significant step forward for these patients," says Phillip Low, M.D., Mayo Clinic neurologist and lead study investigator. "This would be a good drug to provide the first line of treatment."

The drug, pyridostigmine, has been used for years for myasthenia gravis, a neuromuscular transmission disorder. Dr. Low hypothesized that it would also improve nerve cell transmission for orthostatic hypotension patients and trigger the reflex that controls blood pressure in all positions.


Of the 58 patients in Dr. Low’s study, one-third were able to stop taking any other orthostatic hypotension medications, and others were able to lower the amount of other drugs needed. Orthostatic hypotension is especially common in those over age 70. In general, blood pressure control lessens as one ages, according to Dr. Low. Common causes of orthostatic hypotension include diabetes, autonomic neuropathy, multiple system atrophy, pure autonomic failure and Parkinson’s disease. Certain drugs, such as diuretics and medication used to control blood pressure, are also common catalysts for the condition. Studies conducted at Mayo Clinic by Peter Dyck, M.D., neurologist, indicate 10 percent of diabetics have orthostatic hypotension.

The challenge with trying to fix this condition, according to Dr. Low, is that most medications that increase blood pressure raise blood pressure in all positions. Thus, the drugs would work for patients with orthostatic hypotension when they stood up, but their blood pressure would be too high when lying down, increasing their risk of stroke. Dr. Low felt that this price was too high, and that treating with medications that raised blood pressure while standing but raised blood pressure while lying down amounted to trading one problem for another.

"We wanted a ’smart drug’ that would only increase blood pressure when standing up, and not when lying down," says Dr. Low. Pyridostigmine works at the level of the autonomic ganglion, which has minimal nerve signaling traffic when lying down. When standing up, however, nerve signaling traffic in the autonomic ganglion increases, so the researchers theorized that a drug that affected the autonomic ganglion would improve orthostatic hypotension patients’ standing blood pressure but not increase the blood pressure while lying down.

After a small, open trial of 15 subjects in which the pyridostigmine performed effectively as hoped, the investigators proceeded to the current double-blinded study of 58 patients. The patients either received placebo, pyridostigmine alone or pyridostigmine in combination with one of two low dosages of midodrine, a drug previously proven to improve orthostatic hypotension.

The effects of the drugs were measured one hour post-treatment. Pyridostigmine significantly improved the patients’ standing blood pressure without elevating blood pressure while lying down. The positive effects of the drug were even further improved when combined with low-dose midodrine. Improvement of blood pressure was associated with improvement of symptoms while standing. Side effects from pyridostigmine were minor and transient, including some abdominal cramping or need to go to the bathroom more often than usual.

Paola Sandroni, M.D., another Mayo Clinic neurologist, conducted a follow-up study of the first 45 patients in the study led by Dr. Low; the follow-up study occurred an average of 19.5 months after the first trial. Detailed information was available on 32 patients, and 75 percent reported either good or excellent results from the pyridostigmine treatment. Approximately one in four were able to manage on pyridostigmine alone, and one in three needed other medications, yet were able to reduce the dose of the other medication (e.g., midodrine or fludrocortisone). "By the time they come to see us at Mayo Clinic, the majority of our orthostatic hypotension patients have had multiple treatments and have not done very well," says Dr. Low. "They are very grateful to have found this drug [pryridostigmine]."

The next step in the orthostatic hypotension research will involve seeking out an even smarter drug combination involving pyridostigmine that might work on multiple levels.

Lisa Lucier | EurekAlert!
Further information:
http://www.mayo.edu

More articles from Health and Medicine:

nachricht Fast-tracking T cell therapies with immune-mimicking biomaterials
16.01.2018 | Wyss Institute for Biologically Inspired Engineering at Harvard

nachricht Dengue takes low and slow approach to replication
12.01.2018 | Duke University

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Scientists decipher key principle behind reaction of metalloenzymes

So-called pre-distorted states accelerate photochemical reactions too

What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...

Im Focus: The first precise measurement of a single molecule's effective charge

For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.

Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...

Im Focus: Paradigm shift in Paris: Encouraging an holistic view of laser machining

At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.

No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...

Im Focus: Room-temperature multiferroic thin films and their properties

Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.

Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...

Im Focus: A thermometer for the oceans

Measurement of noble gases in Antarctic ice cores

The oceans are the largest global heat reservoir. As a result of man-made global warming, the temperature in the global climate system increases; around 90% of...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

10th International Symposium: “Advanced Battery Power – Kraftwerk Batterie” Münster, 10-11 April 2018

08.01.2018 | Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

 
Latest News

Novel 3-D printing technique yields high-performance composites

16.01.2018 | Materials Sciences

New application for acoustics helps estimate marine life populations

16.01.2018 | Life Sciences

Fast-tracking T cell therapies with immune-mimicking biomaterials

16.01.2018 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>