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The incidence of blood clot-related strokes fell among whites in the Greater Cincinnati/Northern Kentucky area for the first time, according to long-term surveillance study representative of strokes in blacks and whites nationwide reported in Stroke: Journal of the American Heart Association.

However, there was no decrease in stroke rates among blacks.

“It’s encouraging that, for the first time ever in our study area, there is a drop in the most common type of stroke,” said Dawn Kleindorfer, M.D., lead author of the study and assistant professor of neurology at the University of Cincinnati. “However, it’s very disappointing that the racial disparity seems to be getting worse.”

Investigators found that the age-adjusted annual rate of ischemic stroke (those caused by a blood clot) resulting in hospitalization changed between 1999 and 2005 from:
189 to 167 per 100,000 overall, an 11.6 percent drop;
180 to 154 per 100,000 among whites, a 14.4 percent reduction;
263 to 275 per 100,000 among blacks, a 4.6 percent rise, but not a significant change.

The patterns remained the same when out-of-hospital strokes were included. During the same period, researchers found no change in the rate of hemorrhagic strokes (those caused by bleeding).
The likelihood of dying after an ischemic stroke remained steady over time and was similar in whites and blacks, about 10 percent, according to the report.

Researchers used data from the Greater Cincinnati/Northern Kentucky Stroke Study, which gathered information on all first strokes occurring in a five-county area with 1.3 million people. The counties include urban, suburban and rural areas. It’s comparable to the nation in education, income and in the percentage of blacks (18 percent), but does not include a substantial proportion of persons of Hispanic ethnicity (less than 3 percent).

“When you look at national maps on mortality, you see many more stroke deaths in blacks,” Kleindorfer said. “According to our data, this occurs because blacks are far more likely to have a stroke to begin with, not because they are more likely to die once the stroke happens.”

The racial disparity could not be explained by differences in the occurrence and treatment of stroke risk factors. According to a telephone survey conducted in the study area, blacks were more likely than whites to have been diagnosed with risk factors such as high blood pressure and diabetes, but they were also more likely to be receiving treatment for these conditions.

“We’ve done a lot of work in the community to increase stroke awareness and encourage prevention, but the stroke rates are absolutely stable in blacks,” Kleindorfer said.

The investigators are collecting 2010 data in their ongoing phase of their epidemiology of stroke project.
Stroke is the third leading cause of death in the United States and a leading cause of major disability in adults.

Co-authors are Jane Khoury, Ph.D.; Charles J. Moomaw, Ph.D.; Kathleen Alwell, R.N.; Daniel Woo, M.D.; Matthew L. Flaherty, M.D.; Pooja Khatri, M.D.; Opeolu Adeoye, M.D.; Simona Ferioli, M.D.; Joseph P. Broderick, M.D.; and Brett M. Kissela, M.D. Individual author disclosures are on the manuscript.

Patients treated over long periods with metformin, a common drug for diabetes, are at risk of developing vitamin B12 deficiency which is also likely to get worse over time, according to a study published Friday.

Dutch scientists who carried out the study said the findings suggest that regular checking of vitamin B-12 levels during long-term metformin treatment should be “strongly considered” to try to prevent deficiency and its effects.

Vitamin B12 is essential to maintain healthy nerve cells and red blood cells. It is found in meat, dairy products, eggs, fish, shellfish and fortified breakfast cereals, and it also can be taken as a supplement.

Coen Stehouwer of Maastricht University Medical Center in the Netherlands, whose study was published in the British Medical Journal, said symptoms of B12 deficiency include fatigue, mental changes, anemia and nerve damage known as neuropathy.

All these symptoms can easily be misdiagnosed as being due to diabetes and its complications, or to aging, he said, but checking B12 levels could help doctors to assess the real cause and treat it if it was found to be B12 deficiency.

“Our data provide a strong case for routine assessment of vitamin B12 levels during long term treatment with metformin,” Stehouwer wrote.

An estimated 246 million people around the world have diabetes and rates are expected to rise along with the number of people who are overweight or obese. Most sufferers have type 2 diabetes, the kind linked with poor diet and lack of exercise.

Stehouwer’s team studied 390 patients with type 2 diabetes, giving metformin to 196 of them three times a day for more than four years, and a placebo, or dummy pill, to the other 194.

They found that people who had taken the metformin had a 19 percent reduction in their vitamin B12 levels compared with people who had taken a placebo, who had almost no B12 change.

The reduced levels of vitamin B12 in the metformin group also persisted and became more apparent over time, they said.

“Our study shows that it is reasonable to assume harm will eventually occur in some patients with metformin-induced low vitamin B12 levels,” Stehouwer wrote.

In a comment on the study, Josep Vidal-Alaball, a specialist in primary care and public health at Heath Park in Cardiff, Wales, said assessments should be carried out to see if giving patients advice on B12 in their diets would solve the problem.

“If it does not, a trial of screening for vitamin B-12 deficiency in patients taking metformin would be needed,” he wrote.

New research has found that an experimental Ebola vaccine developed by researchers at the National Institutes of Health protects monkeys against not only the two most lethal Ebola virus species for which it was originally designed, both recognized in 1976, but also against a newer Ebola virus species that was identified in 2007.

Nancy J. Sullivan, Ph.D., of the Vaccine Research Center at the National Institute of Allergy and Infectious Diseases (NIAID), NIH, led the study team, which included collaborators from the U.S. Army Medical Research Institute for Infectious Diseases in Fort Detrick, Md., and the Centers for Disease Control and Prevention. Their findings appear May 20 in the open-access journal PLoS Pathogens. Currently, there are no specific treatments or vaccines available to control Ebola outbreaks.
Transmission electron micrograph of Ebola virus. Credit: CDC
Transmission electron micrograph of Ebola virus. Credit: CDC

“The important work by Dr. Sullivan and her colleagues shows that it is possible to generate immunity to newly identified species of Ebola virus with a vaccine originally designed to protect against a different species,” says NIAID Director Anthony S. Fauci, M.D. “This finding will guide future vaccine design and may open an avenue for developing a single vaccine that works against both known and emerging Ebola virus species.”

The experimental Ebola vaccine being developed at NIAID has two components, a prime and a boost. The prime consists of a DNA vaccine containing a small piece of genetic material encoding surface proteins from Zaire ebolavirus and Sudan ebolavirus. The boost consists of a weakened cold virus that delivers the Zaire ebolavirus surface protein.

Previously, Dr. Sullivan and her collaborators demonstrated that the prime-boost strategy produces a strong antibody response in monkeys. More importantly, the experimental vaccine induces a robust reaction by the cellular arm of the immune system. The cellular arm includes T cells, which help orchestrate the overall immune response.

“An ideal Ebola vaccine would stimulate broad immunity so that we wouldn’t have to scramble to create entirely new vaccines whenever new virus species are identified,” notes Dr. Sullivan.

However, developing one vaccine to protect against multiple Ebola virus species poses a challenge, she says. To the antibody-producing arm of the immune system, each species looks different. Neutralizing antibodies that recognize one Ebola species cannot readily recognize, or cross-neutralize, the others. T cells, in contrast, can cross-react, even when the target viruses share only small pieces in common.

After the emergence of Bundibugyo ebolavirus (BEBOV) in 2007, Dr. Sullivan’s team decided to revisit the prime-boost vaccine regimen to see if the cellular immunity generated would confer protection against the new virus species.
Researcher working in a biosafety level 4 laboratory.
Credit: U.S. Army Medical Research Institute of Infectious Diseases
Researcher working in a biosafety level 4 laboratory.
Credit: U.S. Army Medical Research Institute of Infectious Diseases

Four cynomolgus macaques received the DNA prime vaccine. A year later, the animals were boosted with the vector vaccine. Shortly after the boost, the four vaccinated monkeys and four unvaccinated ones serving as controls were exposed to lethal levels of BEBOV. All the unvaccinated animals became ill, and three died. None of the vaccinated animals showed any sign of illness. Analysis showed that the vaccinated monkeys developed T-cell responses sufficient to prevent or control infection by the novel Ebola virus species, even though the vaccine did not contain material from BEBOV and no antibodies against BEBOV were produced. The animal study was conducted in maximum-level biosafety containment laboratories at U.S. Army Medical Research Institute of Infectious Diseases.

Now the research team is evaluating what parts of the T-cell response were critical to the vaccine’s success against BEBOV. “Once we identify those critical aspects, we can design future vaccines to better elicit that desired immune cell-based activity and perhaps make a single vaccine that protects against all Ebola virus species,” says Dr. Sullivan.

Additional information on NIAID research on Ebola and other hemorrhagic fever viruses can be found at http://www.niaid.nih.gov/topics/ebolamarburg/pages/default.aspx.

Male fat tissue and female fat tissue are genetically distinct from one another, new research on lab animals reveals.

The observation — based on work conducted solely with mice — might explain why men tend to store fat in their bellies, while women tend to pile it on their hips.

Researchers from UT Southwestern Medical Center explored the question by focusing on the fat distribution patterns of mice, which are similar to those of people. Genes were taken from the belly and hip fat of male mice and female mice, as well as from female mice whose ovaries had been removed to mimic human female menopause.

A genetic comparison of the removed fat cells revealed that out of approximately 40,000 mouse genes, only 138 were common to both genders.

“This was completely unexpected,” Dr. Deborah Clegg, UTSMC senior author and assistant professor of internal medicine, said in a news release. “We expected the exact opposite — that 138 would be different and the rest would be the same between the sexes.”

Clegg and her colleagues note that men tend to carry excess weight around their gut area, while pre-menopausal women are more likely to carry it around their butt, hips, and thighs. After menopause, stored fat in women then shifts to the waist area, following a drop in ovarian hormone levels.

Aside from genetic differences, fat tissue also seemed to differ in other basic ways, as male mice fed a high-fat diet for 12 weeks gained more weight than similarly fed female mice. Male fat tissue also seemed more prone to inflammation than female fat tissue, the authors noted.

On the other hand, female mice whose ovaries had been removed started to exhibit weight gain and inflammation patterns similar to those of the male mice.

The findings led the research team to suggest that ovarian hormones play a critical role in where fat gets deposited in women.

The finding is reported in the current issue of the International Journal of Obesity.

The standard criteria psychiatrists use to diagnose anorexia nervosa and bulimia may be too rigid and exclude many patients who urgently require treatment for eating disorders, a new study suggests.

These patients are typically categorized as “Eating Disorder Not Otherwise Specified” (EDNOS), which has become a “mosh pit” that lumps dissimilar patients into a single category that’s poorly recognized by doctors and health insurers, according to primary author Dr. Rebecka Peebles, an adolescent medicine specialist with the Comprehensive Eating Disorders Program at Lucile Packard Children’s Hospital in California.

The EDNOS label is “a bit misleading to patients — it can make them feel like they don’t have a real eating disorder,” Peebles said in a hospital news release.

She and her colleagues investigated whether adolescents with EDNOS are less ill than those who meet the full diagnostic criteria for anorexia or bulimia. The researchers examined the medical records of more than 1,300 female patients treated for eating disorders at Packard Children’s, and created categories of “partial anorexia nervosa” and “partial bulimia nervosa” for patients who didn’t quite meet the full criteria for these diseases.

Among the findings:
Nearly two-thirds of the patients had been categorized as EDNOS.
Patients with partial anorexia were more similar to patients with full-blown anorexia than to other EDNOS patients with partial bulimia.
About 60 percent of the EDNOS patients met medical criteria for hospitalization and, on average, were sicker than patients diagnosed with full-blown bulimia.

The sickest EDNOS patients were those who had lost more than 25 percent of their body weight before diagnosis and had severe malnutrition. These girls had been overweight and lost weight too fast and dangerously in order to achieve what’s considered a normal weight. In some ways, these girls were worse off than underweight patients diagnosed with anorexia.

“People were initially just patting them on the back for their weight loss. It often took months or years for others to realize that what they were doing didn’t seem healthy,” Peebles said in the news release.

She believes that the findings, published online April 12 in the journal Pediatrics, suggest the need for re-evaluation of the medical criteria for eating disorders.

SOURCE: Lucille Packard Children’s Hospital, news release

Deaths of women in and around childbirth have gone down by an average of 35 percent globally, according to a study using new methods, but are surprisingly high in the United States, Canada and Norway.

The researchers said Monday their findings show it is possible to save women’s lives if countries want to and said their analysis should point to ways to do so.

The AIDS pandemic alone, they said, killed more than 61,000 women in and around the time of childbirth in 2008, most of them in Africa.

“These findings are very encouraging and quite surprising. There are still too many mothers dying worldwide, but now we have a greater reason for optimism than has generally been perceived,” said Dr. Christopher Murray of the Institute for Health Metrics and Evaluation at the University of Washington, who led the study.

The findings contradict work done by the World Health Organization, which reported last May that mothers and newborns are no more likely to survive now than 20 years ago.

Murray and colleagues took every bit of data they could find on deaths of women from records in 181 countries and plugged this information into a computer model.

“We estimated that there were 342,900 deaths worldwide in 2008, down from 526,300 in 1980,” they wrote in their report, published in the Lancet medical journal.

They found the number of women dying from pregnancy-related causes has dropped by more than 35 percent globally in the past 30 years.

“One of the most surprising results is the apparent rise in the maternal mortality rate in the USA, Canada, and Norway,” they added. But it can partly be because U.S. death certificates recently started asking about pregnancy, they added.

But this does not explain why U.S. maternal deaths are double the rates in Britain, triple the rates in Australia and four times the rate in Italy, they said.

In the United States the rate rose from 12 deaths per 100,000 live births in 1980 to 17 in 2008. In Canada, the rate hovered between 6 and 7 for the whole time and Norway’s rose from 7 per 100,000 in 1980 to 8 per 100,000 in 2008.

The United States is currently embroiled in reforming its healthcare system, where more is spent per capita than in comparable developed countries but with poorer results, as demonstrated by maternal and newborn death rates and high rates of diabetes and heart disease.

China, Egypt, Ecuador and Bolivia made some of the most progress in lowering maternal death rates, Murray’s team found.

In China, the rate fell from 165 per 100,000 to 40 per 100,000.

“Progress overall would have been greater if the HIV epidemic had not contributed to substantial increases in maternal mortality in eastern and southern Africa,” they added.

Nearly one out of every five maternal deaths or a total of 61,400 in 2008, were associated with AIDS infections.

About 80 percent of all deaths of pregnant women or new mothers were in 21 countries, with half of all such deaths in just six countries — India, Nigeria, Pakistan, Afghanistan, Ethiopia, and the Democratic Republic of the Congo.

“Finding out why a country such as Egypt has had such enormous success in driving down the number of women dying from pregnancy-related causes could enable us to export that success to countries that have been lagging behind,” Murray said.

A diet rich in carbohydrates that are quickly transformed into sugar in the blood raises the risk of heart disease for women, a new Italian study finds.

The same effect, however, is not seen in men, according to the report, published April 12 in the Archives of Internal Medicine.

The study, by researchers at Italy’s National Cancer Institute, looked not only at total carbohydrate intake but also at what is known as the glycemic index of those carbohydrates — a measure of how quickly and to what extent blood sugar rises after intake of specific carbohydrates.

Carbohydrate foods with similar calorie content can show widely different scores on the glycemic index. Carbohydrates with a high glycemic index include corn flakes, white bread and white rice. Those with lower scores include whole wheat products and sweet potatoes.

“A high glycemic index is known to increase the concentration of triglycerides and lower the concentration of HDL cholesterol, the good kind,” explained Victoria J. Drake, director of the Micronutrient Information Center at the Linus Pauling Institute of Oregon State University, who has studied the subject. “Those adverse effects make it a stronger risk factor for heart disease.”

The Italian researchers got their information on dietary intake from questionnaires filled out by 15,171 men and 32,578 women. Following them for nearly eight years, the researchers found that women who consumed the most carbohydrates overall had about twice the incidence of heart disease as those who consumed the least. Closer analysis showed that the risk was associated with higher intake of high-glycemic foods.

“Thus, a high consumption of carbohydrates from high-glycemic index foods, rather than the overall quantity of carbohydrates consumed, appears to influence the influence of developing coronary heart disease,” the researchers wrote.

Previous studies have seen the same effect in other groups of women, Drake said. They include the Nurses Health Study, done in the United States, and studies of women in the Netherlands.

No effect from total carbohydrate consumption or consumption of foods with a high-glycemic index was seen in men in the Italian study, a pattern also seen in other studies, Drake added.

“There is definitely a gender difference,” she noted.

The difference might be due to the action of sex hormones, the researchers speculate. Male hormones, androgens, appear to slow the transformation of carbohydrates into blood sugar, whereas the female hormone estrogen speeds the process, she said.

Dr. Suzanne Steinbaum, director of women and heart disease at Lenox Hill Hospital in New York City, said the study shows the need for women to be more aware of the nature of the carbohydrates in their diet.

“An emphasis needs to be placed on a diet that is not simply low in carbohydrates but rather low in simple sugars, as measured by the glycemic index,” Steinbaum said.

There’s a simple way to determine the glycemic index of a food, she said.

“Look at the label,” Steinbaum said. “It says ‘carbohydrates.’ Under that, it says ’sugars.’ When you have a high number for sugars, that’s a way to know what the glycemic index is.”

That index can differ widely in foods that don’t appear to be different, she said. One breakfast cereal may have a sugar content of 16 grams, but another may have just 3 grams to 6 grams.

“If you see a high level of sugar, that’s the one to stay away from,” Steinbaum said.

SOURCES: Victoria J. Drake, Ph.D., research associate, Linus Pauling Institute, Oregon State University, Portland; Suzanne Steinbaum, D.O., director, women and heart disease, Heart and Vascular Institute, Lenox Hill Hospital, New York City;

Scientists have shown that through an eye exam, doctors can identify infants who are most likely to benefit from early treatment for a potentially blinding eye condition called retinopathy of prematurity (ROP), resulting in better vision for many children.

These long-term results of the Early Treatment for Retinopathy of Prematurity (ETROP) study confirm that the visual benefit of early treatment for selected infants continues through 6 years of age. The research, published April 12 online in Archives of Ophthalmology, was supported by the National Eye Institute (NEI), part of the National Institutes of Health.

“This study has set the standard of care for infants with ROP by showing that early treatment of selected high-risk premature babies has positive longer-term results on vision,” said NEI Director Paul A. Sieving, M.D., Ph.D.

An estimated 15,000 premature infants born each year in the United States are affected by some degree of ROP. At-risk infants generally are born before 31 weeks of the mother’s pregnancy and weigh 2.75 pounds or less.

This disease, which usually develops in both eyes, is one of the most common causes of vision loss in children. About 90 percent of infants with ROP have a mild form that does not require treatment, but those who have a more severe form can develop lifelong visual impairment, and possibly blindness.

During pregnancy, the blood vessels of the eye gradually grow to supply oxygen and essential nutrients to the light-sensitive retina. If a baby is born prematurely, growth of the blood vessels may stop before they reach the edge of the retina. In these newborns, abnormal, fragile blood vessels and retinal tissue may develop at the edges of the normal tissue. The abnormal vessels can bleed, resulting in scars that pull on the retina. The main cause of visual impairment and blindness in ROP is retinal detachment. Laser therapy or cryotherapy, using freezing temperatures, are the most effective treatments to slow or stop the growth of abnormal blood vessels.

“The long-term study has given clinicians evidence that infants with ROP should be treated with different strategies based on an infant’s risk for a severe form of the disease, which can be determined through an exam at the bedside,” said study chair William V. Good, M.D., of Smith-Kettlewell Eye Research Institute in San Francisco.

Previously, doctors treated infants with ROP when they estimated their risk for retinal detachment to be 50 percent, a strategy developed through the NEI-supported Cryotherapy for Retinopathy of Prematurity study. Although this was a major finding, many infants still went on to develop severe eye disease. Therefore, the first phase of the ETROP study aimed to discover if doctors could identify infants at a higher risk for progression of the disease and intervene early to improve their vision.

In 2003, the ETROP study found that early treatment—upon diagnosis as higher risk for severe ROP—improved the vision and retinal health of certain infants after nine months. These infants had dilated or twisted blood vessels in the retina and substantial growth of new blood vessels, classified as Type 1 disease. Eyes with Type 2 ROP, or a more moderate amount of new blood vessel growth, did not benefit from early treatment. Doctors could predict which infants were more likely to benefit from early treatment by identifying certain eye characteristics, such as the appearance and location of the blood vessels.

The current study followed the same 370 children through 6 years of age, when researchers checked their vision and examined the development of their eyes. The nine-month study recommendations were confirmed through 6 years. Type 1 eyes benefitted from early treatment, and Type 2 eyes had similar results with either early treatment or treatment at the standard time. Seventy-five percent of the early-treated Type 1 eyes were spared legal blindness, compared with 67 percent of Type 1 eyes that received treatment at the standard time. Of the Type 2 eyes that were carefully monitored for disease progression through the standard protocol, more than half improved without treatment.

“Unfortunately, not all eyes selected for early treatment do well,” said Robert J. Hardy, Ph.D., director of the ETROP study coordinating center and professor of biostatistics at the University of Texas School for Public Health in Houston. “Additional research is needed to identify still better methods for the prevention and treatment of severe ROP.”

Older adults who take powerful prescription painkillers known as opioids face an increased risk of bone fractures, especially at moderately high medication doses, a new study finds.

Opioids are powerful narcotic pain medications that include morphine, oxycodone (Oxycontin and other brands) and hydrocodone (Vicodin and others).

The drugs work well against severe pain in the short term, but their longer-term effectiveness for chronic pain is less clear. Moreover, with longer use comes the risk of addiction, in addition to side effects such as nausea, constipation, dizziness and sedation.

That dizziness and sedation can also set opioid users up for falls, which, in older people especially, may result in serious fractures.

The new study, published in the Journal of General Internal Medicine, confirms the risk of fracture associated with opioids, and also shows that moderately higher drug doses further the hazard.

Researchers found that among more than 2,300 older adults with chronic pain, the risk of suffering a bone fracture was higher when patients were using an opioid for a prolonged period than when they were opioid- free.

The individuals in the study were 60 years of age or older. None of the patients was suffering from cancer-related pain. (Guidelines for treating severe cancer pain are often different than guidelines for non-cancer pain.)

The annual rate of fractures among study participants who were not currently using opioids was just under 4 percent, while current users showed a fracture rate of 6 percent. And among patients currently taking opioid doses of at least 50 milligrams per day, the annual fracture rate was 10 percent.

According to the researchers, 50 milligrams is considered to be in the moderate range for opioid doses.

“Some of these fractures were significant,” said senior researcher Dr.

Michael Von Korff, of the Group Health Research Institute in Seattle.

In an interview, he noted that 37 percent of fracture victims ended up in the hospital and nearly one-quarter entered a nursing home within one month of the accident.

The findings come at a time when long-term opioid use for non-cancer- related pain is coming under increased scrutiny.

About 8 million Americans are using opioids to control chronic pain, Von Korff said, yet the long-term effectiveness of the drugs is uncertain, and may vary widely from person to person. Some people find relief, while others find their pain actually worsens, Von Korff noted.

A report published in October by the Cochrane Collaboration, an international medical research organization, concluded that for older adults with osteoarthritis, the risks of long-term opioids may outweigh the modest pain relief.

And in a separate study published this week in the Annals of Internal Medicine, Von Korff’s team highlights the potential for overdose among people with legitimate prescriptions.

The researchers found that among 10,000 patients on opioids for at least three months, 51 suffered at least one overdose, with fatal results for six. As in this latest study, higher medication doses conferred a greater risk.

The bottom line, Von Korff said, is that “these drugs need to be taken cautiously and under close medical supervision.”

The current study included 2,341 older adults who, at some point between 2000 and 2005, were prescribed opioids for at least 90 days — most commonly for chronic back pain, osteoarthritis or pain in the extremities.

To limit the risks of falls and other side effects, Von Korff said that patients on opioids should work with a single physician who is aware of all the medications they are taking. That will help avoid any potentially hazardous drug interactions.

And given the importance of dosage, Von Korff said, “never use more medication than your doctor has prescribed.”

He also advised opioid users who feel overly sedated or have had dizziness or falls to tell their doctors about it.

SOURCE: Journal of General Internal Medicine

Babies of women who smoked during pregnancy have blood pressure problems at birth that persisted through the first year of life, a new study finds.

“What is of concern is that the problems are present at birth and get worse over time,” said Gary Cohen, a senior research scientist in the department of women and child health at the Karolinska Institute in Stockholm, and lead author of a report in the Jan. 25 online edition of Hypertension. “They’re not going away, they’re getting worse.”

The study led by Cohen compared 19 infants of nonsmoking couples with 17 infants born to women who smoked an average of 15 cigarettes a day during pregnancy. At one week of age, the infants of nonsmoking mothers experienced a 2 percent increase in blood pressure when tilted upright, with a 10 percent increase at one year. The pattern for the children of smoking mothers was reversed: a 10 percent blood pressure increase at one week, a 4 percent increase at one year.

And the heart rate response to tilting of the children of mothers who smoked was abnormal and exaggerated, the report said.

It’s not possible to say whether the abnormalities seen in the babies will lead to trouble later in life, Cohen said. But, he noted, “the extent of the condition at one year suggests that it is not going to disappear quickly.”

The reason why exposure to tobacco in the womb affects blood pressure is not clear, Cohen said. A leading possibility is that “smoking might damage the structure and function of blood vessels,” he said, mainly by damaging the endothelium, the delicate layer of cells that line the interior of blood vessels.

Whether that damage will persist is not known. “We’re only up to 12 months at the moment,” he said. “We plan to follow them.”

The damage seen in the Karolinska study is similar to that observed in babies born to mothers whose pregnancies were marked by such abuses as drug use, said Barry M. Lester, a professor of psychiatry and pediatrics at Brown Medical School, and director of the Brown Center for the Study of Children at Risk.

“Early kinds of natal insults can cause reprogramming of brain circuitry,” Lester explained. He has led studies of the long-term effects of cocaine and amphetamine use during pregnancy. Many women who take such drugs also smoke, Lester added.

“When we isolated tobacco effects, we showed that there are inborn neural effects of tobacco exposure similar to what we see in cocaine and methamphetamine abuse,” he said.

Some research has connected such problems to overproduction of cortisol, a “stress hormone” that plays an important role in regulation of blood pressure and the immune system, Lester said. “Cortisol overexposure is one hypothesis,” he said. “There is a lot of evidence showing that too much cortisol is damaging.”

It is a reasonable hypothesis, Cohen said. Babies born preterm have problems with blood pressure that have been linked to overproduction of cortisol by the adrenal glands, he noted, “and there are some parallels between tobacco smoke exposure and preterm babies of the same age.”

Whatever the mechanism of damage, treatment to eliminate the problems after birth does not seem possible, Cohen added.

“What we know from studies in older kids is that even if you remove them from an environment of exposure to tobacco smoke, it is unlikely you will get full restoration of normal function,” he said. “The best intervention to solve these problems is prevention. Women who are pregnant need to avoid exposure to tobacco smoke in the air. Passive smoke exposure can be as bad as being an active smoker.”

SOURCES: Gary Cohen, Ph.D., senior research associate, department of women and child health, Karolinska Institute, Stockholm, Sweden; Barry M. Lester, Ph.D., professor, psychiatry and pediatrics, Brown Medical School, and director, Brown Center for the Study of Children at Risk, Providence, R.I.