No symptoms, but some loss of brain function occurs, study finds  

FromHealthDay

If you’re an older American with no major health problems, chances are about one in 10 that you’ve had a stroke and didn’t know it.

It was probably not severe enough to cause recognizable symptoms, such as vision problems, facial weakness or trouble walking, but it was still a blockage of a brain artery, and it reduced your thinking powers just a bit.

That estimate comes from a new study of 2,040 people, average age 62, in the long-running Framingham Offspring Study. MRI scans showed that 10.7 percent of them had experienced what study author Dr. Sudha Seshadri, an associate professor of neurology at Boston University, called “a silent brain infarct.”

It’s the cerebral equivalent of what physicians call a myocardial infarct — blockage of a blood vessel that causes damage to tissue. In the case of a silent stroke, the blockage and the damage occurs in the brain, without symptoms.

A silent stroke is different from a transient ischemic attack (TIA), a momentary loss of brain function, Seshadri said. A TIA causes some symptoms, while a silent stroke, by definition, doesn’t. But both are warning signs to pay attention to the well-known risk factors for stroke, such as cholesterol levels, blood pressure, obesity and smoking, she said.

The incidence found in the Framingham Offspring study “was within the ballpark of what prior studies have suggested,” Seshadri said. “But this was a group of people who were younger than in most of the prior studies. The fact that one in 10 persons had silent attacks that had subtle side effects on the brain is something we should be concerned about and should address.”

The report was published in the online issue of Stroke.

The effects of a silent brain infarct show up on an MRI scan as “small lesions in various parts of the brain,” Seshadri said. “We can’t tell from that whether they had a symptomatic attack.” And the MRI scans give no clues as to when the silent stroke occurred.

Testing showed that “on average, compared to age-matched controls, those with lesions do have subtle signs, such as loss of flexibility of talk,” she said.

The incidence seen in the study did not startle Dr. Claudette Brooks, director of the neurovascular laboratory at West Virginia University Health Sciences Center.

“When I look for the cause of headaches and similar problems, it doesn’t surprise me when I see these lesions, and other colleagues tell me they see them,” Brooks said.

An even higher rate of silent strokes might be expected in a study of black Americans, she noted. “They have a higher incidence of hypertension [high blood pressure], atherosclerosis, and hyperlipidemia [excess blood fat],” Brooks said.

Nothing special needs to be done to reduce the risk of silent stroke, Seshadri and Brooks both said.

“I wouldn’t recommend that people rush out to have an MRI,” Seshadri said. “It’s up to the medical and public health community to emphasize the importance of controlling risk factors.”

“The whole thing boils down to modifying risk factors,” Brooks said. “If you don’t have risk factors such as high cholesterol, obesity and diabetes, try to keep yourself out of the group that does. If you do, modify them by keeping blood pressure and cholesterol down, things like that.”

 

From Ivanhoe’s Medical Breakthroughs

Every 40 seconds, someone in the United States has a stroke. It’s our nation’s third leading cause of death, but knowing your risk and what the symptoms are could save your life.
At age 38, Nicole Reeder had a massive stroke. “I think the most profound loss I have is adding and subtracting,” she told Ivanhoe. “I was valedictorian of my class, math and physics.” Doctors said she’d never walk again, but Reeder stayed strong. “Nobody is going to tell me I’m not going to walk again. They are telling the wrong person,” she said.
Some risk factors for stroke are unique to women, like pregnancy, says George Levy, M.D., a neurologist at Broward Health Coral Springs Medical Center in Coral Springs, Fla. “That is because there’s a higher plasma volume, blood volume in pregnancy,” Dr. Levy told Ivanhoe. “There’s also a higher risk for thrombosis.”
Birth control pills and hormone replacement therapy also raise a woman’s risk and migraines can increase the risk because of their effect on the brain. “The blood vessels constrict to sometimes a point where the tissue can’t get enough blood supply and of course, that’s the definition of a stroke,” Dr. Levy said. Post-menopausal women with high triglycerides and a waist larger than 35 inches have a five-fold increased stroke risk.
“The focus definitely ought to be on prevention and early treatment,” Dr. Levy said. Stroke symptoms unique to women include sudden face and limb pain, hiccups, nausea, chest pain and shortness of breath.
Doctors think birth control pills, especially after thirty-five, played a role in Reeder’s stroke. “Life is going to hand you lemons, but what are they going to be? Nobody ever knows,” Reeder said. Today, Reeder struggles with her left hand, simple math and memory, but she is walking thanks to sheer determination.

Migraines can increase a man’s risk of stroke too, butmigraines disproportionately affect women. About 18 percent of women suffer from migraines, compared to just six percent of men.

From Reuters

People given a blood pressure drug known as a beta blocker to reduce heart risks before surgery were one-third more likely to die within a month and had double the risk of stroke compared with those given a dummy pill, Canadian researchers said on Monday.

The study is the largest, most rigorous to date looking at whether beta blockers do more harm than good in reducing surgery-related risks. Other, smaller studies have had mixed results.

“There is a real potential that beta blockers are causing serious harm in the surgical setting,” said Dr. P.J. Devereaux of McMaster University in Ontario, whose study appears in the journal Lancet.

“If my mother was undergoing surgery and given a beta blocker, I would be extremely upset based on this evidence.”

The findings challenge the long-held belief that giving people a beta blocker before major surgery protects them from heart risks brought on by the stress of the procedure.

Surgery often raises levels of a stress hormone known as catecholamine, which drives up a person’s blood pressure and heart rate. “Beta blockers block the effects of increased catecholamines, so the physiological rationale would say they would be beneficial to people,” Devereaux said in a telephone interview.

He and colleagues set out to test this idea. They studied more than 8,000 patients in 23 countries at 190 hospitals who were undergoing major surgery unrelated to the heart. People in the study had or were at risk for clogged arteries.

STROKE VS HEART ATTACK

Half were given the beta blocker metoprolol, sold by AstraZeneca as Toprol XL, two to four hours before and 30 days after their surgery. The other half got a placebo.

The doctors were looking for heart complications such as heart-related death, non-fatal heart attacks or a heart-stopping event known as cardiac arrest in which the person survived.

While the study did find people given the drug had fewer heart attacks and abnormal heart rhythms, they also were more likely to die or have a stroke.

The researchers said for every 1,000 people with similar risks undergoing non-cardiac surgery, the drug could prevent 15 people from having a heart attack, three from needing a shock to restore a normal heart beat, and seven from developing a type of heart rhythm known as atrial fibrillation.

But eight more people would die, five would have a stroke, 53 percent would have abnormally low blood pressure and 42 percent would have an abnormally slow heart beat.

“This is an important study because, although the beta blocker reduced the number of heart attacks that occurred following surgery, it caused more strokes, thus on balance causing more harm than good,” Peter Weissberg, medical director of the British Heart Foundation, said in a statement.

“This is why it is so important to undertake large clinical trials rather than assuming drugs will only do what is expected of them.”

Devereaux, who first presented his findings at the American Heart Association meeting in November, said he expects the study to stir debate about whether it is still wise to give patients a beta blocker before a major surgery.

“It is telling us something we didn’t realize in the past,” he said.

From Forbes.com

Strokes have tripled in recent years among middle-aged women in the U.S., an alarming trend doctors blame on the obesity epidemic. Nearly 2 percent of women ages 35 to 54 reported suffering a stroke in the most recent federal health survey, from 1999 to 2004. Only about half a percent did in the previous survey, from 1988 to 1994.

The percentage is small because most strokes occur in older people. But the sudden spike in middle age and the reasons behind it are ominous, doctors said in research presented Wednesday at a medical conference.

It happened even though more women in the recent survey were on medicines to control their cholesterol and blood pressure - steps that lower the risk of stroke.

Women’s waistlines are nearly two inches bigger than they were a decade earlier, and that bulge corresponds with the increase in strokes, researchers said.

In addition, women’s average body mass index, a commonly used measure of obesity, rose from 27 in the earlier survey to 29. They also had higher blood sugar levels.

No other traditional risk factors like smoking, heart disease or diabetes changed enough between the two surveys to account for the increase in strokes.

In a “pre-stroke population” of middle-age women, a tripling of cases is “an alarming increase,” said Dr. Ralph Sacco, neurology chief at the University of Miami Miller School of Medicine.

The study was led by Dr. Amytis Towfighi, a neurology specialist at the University of Southern California in Los Angeles, and presented at the International Stroke Conference in New Orleans.

She used the National Health and Nutrition Surveys, a federally funded project that gives periodic health checkups and questionnaires to a wide sample of Americans. Participants are routinely asked whether a doctor had ever told them they had had a stroke, and about 5,000 middle-aged people answered that question in each survey.

Researchers saw that the stroke rate had spiked in middle-aged women but stayed about the same - around 1 percent - in middle-aged men. So they looked deeper at the responses to see if they could learn why.

Belly fat stood out, Towfighi said. The portion of women with abdominal obesity rose from 47 percent in the earlier survey to 59 percent in the recent one. The change in men was smaller, and previous studies have shown that “abdominal obesity is a stronger risk factor for women than men,” she said.

Men traditionally have had a greater risk of stroke than women, and “women start catching up to men five or 10 years after menopause,” said Dr. Philip Gorelick, neurology chief at the University of Illinois in Chicago and chairman of the stroke conference.

The new research means “we need to redefine our textbooks about stroke in women,” because they may now be more at risk in middle age than men.

Obesity “sets the stage for all the other risk factors to come in” like diabetes and heart disease, Gorelick added.

In other news at the conference, two studies found that stroke patients were more likely to die if they went to hospitals on nights or weekends, echoing other recent studies that found similar risks for heart attack and surgery patients.

Michigan State University doctors analyzed 222,500 stroke cases at more than 850 hospitals participating in an American Heart Association quality improvement program from 2003 to 2007.

In-hospital deaths were about 6 percent for those who arrived during normal business hours and had strokes caused by a clot, compared with 5 percent of those who entered the hospital after-hours. Deaths were 27 percent for off-hour strokes caused by bleeding in the brain versus 24 percent during normal hours.

A second study of 2.4 million stroke patients in California found death rates of 10 percent on weekends and nights versus 8 percent during weekdays.

Despite the poorer outcomes, doctors said no one should ever delay getting help, since any delay raises the risk of death. The best treatments can only be given in the first few hours after symptoms appear.

Experts suspect that healthy diet and lifestyle are at root of reduced riskFrom HealthDay