WASHINGTON — The government has halted a study testing treatments for a brain condition that can cause strokes after early results suggested invasive therapies were riskier than previously thought.


The condition involves a kind of tangle in the brain called an arteriovenous malformation, or AVM. Arteries and veins grow knotted together until eventually some of them burst, causing a bleeding stroke. AVM accounts for a small fraction of hemorrhagic strokes.


But increasingly, brain scans can spot these tangles well before they're at risk of bleeding – raising the question of what to do for patients, if anything. The study aimed to tell if treating them could prevent a stroke later in life.


Early results suggest it may be safer to leave the condition alone, said Columbia University neurologist Dr. Jay Mohr, who helped lead the study.


Nearly three years into the research, the rate of strokes and death was more than three times higher among participants who had received surgery, radiation or other invasive treatment than among patients given medication for headaches and other symptoms.


Mohr couldn't provide precise numbers but said most of the cases were strokes and there were very few deaths.


"From what we can see, our current methods of intervention may pose a greater hazard for health than letting the natural history run itself out," Mohr said.


The National Institutes of Health has stopped enrollment in the study, but participants will be tracked for several more years to see how they fare over time.


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  • Whole Grains


    Eating lots of whole grains could help to <a href="http://www.ncbi.nlm.nih.gov/pubmed/11000647">lower risk of ischemic stroke for women</a>, according to a study in the <em>Journal of the American Medical Association</em>. The findings showed that women who ate the <a href="http://abcnews.go.com/Health/story?id=117936&page=1#.UHL5F_mfGPJ">most whole grains</a> in the study (like the amount you'd get by eating two or three whole grain bread slices every day) had a 30 to 40 percent lower stroke risk, compared with women who ate the fewest whole grains in the study (like the amount you'd get by eating just a half-slice of whole grain bread every day), according to ABC News.




  • Citrus Fruits


    An <a href="http://www.huffingtonpost.com/2012/02/26/citrus-stroke-risk-antioxidant-flavonoid_n_1299753.html">antioxidant found in citrus fruits</a> could help to lower risk of stroke in women, according to a study of 70,000 women earlier this year in the journal <em>Stroke</em>. Researchers from Harvard Medical School and Brigham and Women's Hospital found that women who <a href="http://www.huffingtonpost.com/2012/02/26/citrus-stroke-risk-antioxidant-flavonoid_n_1299753.html">consumed the most flavonoids</a> over a 14-year period had a 19 percent lower risk of stroke than the women who consumed the fewest flavonoids during that time period.




  • Antioxidants


    While antioxidants aren't exactly a food on their own, fruits, vegetables and whole grains that are rich in them are linked with a lower stroke risk for women. Research published in the journal <em>Stroke: Journal of the American Heart Association</em> showed that women with no heart disease history who <a href="http://www.huffingtonpost.com/2011/12/03/antioxidants-stroke-risk-diet-food-vegetables-fruits_n_1124102.html">consumed the most antioxidants</a> from food had a 17 percent lower risk of stroke, and women <em>with</em> a heart disease history who consumed the most antioxidants from food had a <em>57</em> percent decreased risk of hemorrhagic stroke. The researchers, from the Karolinska Institute in Sweden, speculated that the protection comes from <a href="http://www.huffingtonpost.com/2011/12/03/antioxidants-stroke-risk-diet-food-vegetables-fruits_n_1124102.html">antioxidants' ability to stop inflammation </a>and oxidative stress in the body by neutralizing harmful free radicals. Antioxidants can also help to reduce blood clots and lower blood pressure and decrease inflammation, <a href="http://newsroom.heart.org/pr/aha/vegetables-fruits-grains-reduce-219833.aspx">according to the American Heart Association</a>.




  • Low-Fat Dairy


    Consuming low-fat dairy could help to <a href="http://healthland.time.com/2012/04/20/skim-milk-drinkers-rejoice-you-may-have-a-lower-stroke-risk/">lower the risk of stroke</a>, according to a <em>Stroke</em> study. The research showed that the adults who <a href="http://www.webmd.com/stroke/news/20120419/low-fat-dairy-may-help-reduce-stroke-risk">consumed the most low-fat dairy</a> over a 10-year period had a 12 percent lower risk of stroke compared with those who consumed the least low-fat dairy over the time period. "It is possible that <a href="http://www.eurekalert.org/pub_releases/2012-04/aha-eld041612.php">vitamin D in low-fat dairy foods</a> may explain, in part, the observed lowered risk of stroke in this study because of its potential effect on blood pressure," study researcher Susanna Larsson, Ph.D., associate professor of nutritional epidemiology at the Karolinska Institutet, said in a statement.




  • Magnesium-Rich Foods


    Foods <a href="http://www.webmd.com/stroke/news/20120119/magnesium-rich-foods-may-lower-stroke-risk">loaded with magnesium</a> -- like beans, nuts leafy greens and whole grains -- are linked with a lower risk of ischemic stroke, WebMD Reported. The findings, published in the <em>American Journal of Clinical Nutrition</em>, showed specifically that for each 100 milligrams of magnesium consumed each day, ischemic stroke risk went down by 9 percent.




  • Fish


    Making sure to <a href="http://www.reuters.com/article/2011/09/26/us-fish-stroke-idUSTRE78P07V20110926">eat some fish</a> every week could help to lower risk of stroke, according to a review of studies published in the journal <em>Stroke</em>. Reuters reported on the study, which showed that eating fish several times a week was linked with a lower risk of stroke, compared with non-fish eaters. "I think overall, fish does provide a beneficial package of nutrients, in <a href="http://www.reuters.com/article/2011/09/26/us-fish-stroke-idUSTRE78P07V20110926">particular the omega-3s</a>, that could explain this lower risk," Dariush Mozaffarian, an epidemiologist at the Harvard School of Public Health, whose research was part of the <em>Stroke</em> analysis, told Reuters.




  • Learn About Stroke Risks


    Learn the different symptoms of stroke, and what happens inside the body when you suffer a stroke.