Featured Research

from universities, journals, and other organizations

Mini-strokes Linked To Uric Acid Levels

Date:
October 5, 2007
Source:
Johns Hopkins Medical Institutions
Summary:
Researchers have found that high-normal uric acid levels may cause barely-detectable mini-strokes that potentially contribute to mental decline in aging adults. Diet, exercise and drugs like allopurinol (all of which lower UA levels) could eventually be of value in reducing this risk, especially for those with additional risk factors such as diabetes, obesity and hypertension, the researchers say. But they caution that it would be premature to try this now.

Researchers at Johns Hopkins have found that high-normal uric acid (UA) levels may cause barely detectable mini strokes that potentially contribute to mental decline in aging adults.

Related Articles


Diet, exercise and drugs like allopurinol (all of which lower UA levels) could eventually be of value in reducing this risk, especially for those with additional risk factors such as diabetes, obesity and hypertension, the researchers say. But they caution that it would be premature to try this now.

In a study published in the Oct. 2 issue of Neurology, lead author David Schretlen, Ph.D., of the Department of Psychiatry at The Johns Hopkins University School of Medicine, linked UA levels to high volumes of so-called white matter hyperintensities (WMH), which are small dead areas of the brain that occur when brain cells are deprived of oxygen. Lack of oxygen due to clots or burst blood vessels in the brain are hallmarks of classic large strokes.

"Over a lifetime, it is common to have a small number of these mini strokes and not even notice," says Schretlen, "but as the overall volume of WMH increases, the damage can seriously disrupt how quickly we think and how effectively we learn and remember information."

The role of UA is best known in gout, where buildup of the fatty acid creates pain and disability in the feet and toes. However, UA appears to play contradictory roles in the brain, says Schretlen. For example, UA is a powerful antioxidant that might even protect against Parkinson disease and Alzheimer disease, possibly because antioxidants destroy oxygen free radicals that damage tissue.

On the other hand, elevated UA accompanies diabetes, obesity and heart disease, and it is a well-known risk factor for stroke. One possible explanation of its seemingly contradictory nature is that, like a double-edged sword, UA is beneficial, but processes leading to its production can be harmful under some circumstances, says Schretlen.

In the study, Schretlen and his team obtained and analyzed brain MRI scans of 85 men and 92 women between 20 and 92 years of age. All participants had normal levels of UA. However, those with high-normal levels showed 2.6 times the volume of WMH than those with average or low UA. Among subjects 60 years of age or older, those with high-normal levels of UA had four to five times the volume of WMH than others.

Gender differences exist in normal UA ranges. The blood UA concentrations of men are typically about 1 milligram per deciliter (mg/dL) higher than those of women. In this study UA levels ranged from 1.6 to 8.2 mg/dL for men and from 1.5 to 7.2 mg/dL for women. Within these ranges, concentrations greater than or equal to 5.75 mg/dL for men and 4.8 mg/dL for women were classified as high normal.

In a previous study, Schretlen and colleagues examined the relationship between serum UA and cognitive functioning in adults age 60 and older. In that study, elderly adults with high-normal levels of UA were 2.7 to 5.9 times more likely to score in the lowest 25 percent of the group on measures of thinking speed and memory.

"Having found that UA levels are linked to both mild cognitive decline and mini strokes," says Schretlen, "we need to learn how these are related. We have to find out which of these factors steers the boat."

Schretlen says clinical trials with drugs like allopurinol, which have been used safely for decades to treat gout, may be warranted if further research confirms his hypothesis.

Additional authors of this study, all from The Johns Hopkins University School of Medicine, are Anjeli B. Inscore, Psy.D., Tracy D. Vannorsdall, Ph.D., and Godfrey D. Pearlson, M.D., of the Department of Psychiatry and Behavioral Sciences; Barry Gordon, M.D., Ph.D., and H.A. Jinnah, M.D., Ph.D., of the Department of Neurology, and Michael Kraut, M.D., Ph.D., of the Department of Radiology and Radiological Sciences.


Story Source:

The above story is based on materials provided by Johns Hopkins Medical Institutions. Note: Materials may be edited for content and length.


Cite This Page:

Johns Hopkins Medical Institutions. "Mini-strokes Linked To Uric Acid Levels." ScienceDaily. ScienceDaily, 5 October 2007. <www.sciencedaily.com/releases/2007/10/071001172809.htm>.
Johns Hopkins Medical Institutions. (2007, October 5). Mini-strokes Linked To Uric Acid Levels. ScienceDaily. Retrieved February 26, 2015 from www.sciencedaily.com/releases/2007/10/071001172809.htm
Johns Hopkins Medical Institutions. "Mini-strokes Linked To Uric Acid Levels." ScienceDaily. www.sciencedaily.com/releases/2007/10/071001172809.htm (accessed February 26, 2015).

Share This


More From ScienceDaily



More Health & Medicine News

Thursday, February 26, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Sleeping Too Much Or Too Little Might Increase Stroke Risk

Sleeping Too Much Or Too Little Might Increase Stroke Risk

Newsy (Feb. 26, 2015) People who sleep more than eight hours per night are 45 percent more likely to have a stroke, according to a University of Cambridge study. Video provided by Newsy
Powered by NewsLook.com
London Show Dissects History of Forensic Science

London Show Dissects History of Forensic Science

AFP (Feb. 25, 2015) Forensic science, which has fascinated generations with its unravelling of gruesome crime mysteries, is being put under the microscope in an exhibition of real criminal investigations in London. Duration: 00:53 Video provided by AFP
Powered by NewsLook.com
Michigan Couple Celebrates Identical Triplets

Michigan Couple Celebrates Identical Triplets

AP (Feb. 25, 2015) A suburban Detroit couple who have two older children are adjusting to life after becoming parents to identical triplets _ a multiple birth a doctor calls rare. (Feb. 25) Video provided by AP
Powered by NewsLook.com
Mayor Says District of Columbia to Go Ahead With Pot Legalization

Mayor Says District of Columbia to Go Ahead With Pot Legalization

Reuters - News Video Online (Feb. 25, 2015) Washington&apos;s mayor says the District of Columbia will move forward with marijuana legalization, despite pushback from Congress. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins