Diabetes in pregnancy, poverty linked to ADHD

NEW YORK (Reuters Health) - Babies born to poor mothers with pregnancy-related diabetes have an extra-high risk of developing attention-deficit/hyperactivity disorder, a new study suggests.

So-called gestational diabetes typically develops during the second or third trimester of pregnancy, especially in women who are overweight before getting pregnant, eat an unhealthy diet and don't exercise. It affects between two and 10 percent of pregnant women, according to national data, and rates are rising alongside type II diabetes in the general public.

While the new study doesn't prove that moms' gestational diabetes leads to ADHD in kids, it's likely that diabetes-related changes in the blood shared by mother and fetus could affect how babies' brains develop, researchers said.

"There seems to be more research going in the direction that... the brains of children with ADHD are different," said Ginette Dionne, who has studied gestational diabetes and language development at Laval University in Quebec but wasn't involved in the new study.

"Gestational diabetes may not be a specific cause (of ADHD), but may be one of the factors that affects brain development," she added.

Researchers from the Mount Sinai School of Medicine in New York led by Dr. Yoko Nomura recruited 212 preschoolers for their study, two-thirds of whom were at risk for ADHD, based on teacher and parent reports.

According to interviews with their moms, 21 had been diagnosed with gestational diabetes while pregnant.

The researchers found that at ages three to four, kids whose mothers had had gestational diabetes scored worse on tests of language, memory and IQ than those with diabetes-free moms. And at age six, they had more communication and attention problems.

The effect seemed to be most pronounced in kids born to moms with gestational diabetes who were also poor. Those kids were 14 times more likely to meet the criteria for an ADHD diagnosis at age six, compared to kids of moms who were middle class or well-off and hadn't had gestational diabetes.

Babies of women who'd had gestational diabetes but weren't poor, or were poor but diabetes-free, were not at increased risk of ADHD, the researchers report in the Archives of Pediatrics & Adolescent Medicine.

In cases of gestational diabetes, babies get exposed to extra glucose in the blood that passes through the placenta, researchers said. Diabetes could also affect the amount of oxygen or iron in that blood.

Something about the altered blood, or the way the baby's body responds to it, may interfere with brain development.

"Really right now we have no idea what the specific culprit is," Dionne told Reuters Health.

"What the cumulative data is showing is there is something happening to the brain development of babies of these mothers that have gestational diabetes, and it doesn't seem to affect all babies equally."

Environment after birth also appears to play a role -- kids who grow up in disadvantaged families might not be able to bounce back from early developmental issues, according to experts.

"If you have a subtle problem, if you have better medical care, better food, better intellectual stimuli, you might be able to fix it," Nomura told Reuters Health.

"But if you're born into a harsher, more adverse environment, maybe that tiny little problem acts as a bigger hindrance developmentally."

Researchers agreed that the findings reinforce the importance for women who are planning to become pregnant of getting their weight under control and improving their diet to lower their chances of developing gestational diabetes.

"It is equally important not to frighten pregnant women because (gestational diabetes) is relatively common," said Asher Ornoy, who studies the effects of gestational diabetes at the Hebrew University of Jerusalem, Israel, in an email to Reuters Health.

"Hence preventive measures -- early diagnosis, good nutrition in pregnancy, avoiding overweight... are very important."

SOURCE: http://bit.ly/yxbpbf Archives of Pediatrics & Adolescent Medicine, online January 2, 2012.

Read more »

Posted in: HEALTH

Vitamin D has mixed effects on cancer, broken bones

NEW YORK: Extra vitamin D and calcium may offer some protection against fractures in elderly people, but have little or no impact on cancer risk, according to a fresh look at the medical evidence.

Some research has suggested that vitamin D, with or without calcium, might help stave off cancer, but recent trials have slashed those hopes.

"It turns out that as a group, all of the micronutrient supplements have been disappointing," said Dr. Michael Pollak, who heads the division of cancer prevention at McGill University in Montreal, Canada, and was not involved in the new work.

"Even one of the best candidates, which is vitamin D, is certainly no slam dunk," he told Reuters Health.

The new report, out Monday in the Annals of Internal Medicine, was commissioned by the government-backed U.S. Preventive Services Task Force to inform its public recommendations.

It pulls together 19 gold standard experiments -- so-called randomized controlled trials -- on vitamin D with or without calcium. The trials lasted anywhere from seven months to seven years and ranged in size from a few thousand participants to tens of thousands.

Only three of them reported on cancer, however. While one small study found some protection against cancer in postmenopausal women taking vitamin D and calcium, the larger studies found no benefits.

"I don't have confidence in any of the findings because they could be chance findings," lead researcher Mei Chung, of Tufts Medical Center in Boston, told Reuters Health.

Last month, another randomized controlled trial was published in the Journal of Clinical Endocrinology and Metabolism. Although it wasn't included in Chung's report, it confirms her results.

In that study, among seniors taking 800 IU of vitamin D daily for a few years, 32 out of every 100 died during the study, while 33 out of every 100 people who did not get the supplement died.

That small difference could easily have been due to chance, the researchers found. There were no differences in deaths from cancer or heart disease either, just as calcium also proved unhelpful.

According to Chung, one large U.S. study, known as the Women's Health Initiative, also showed that women taking the supplements had higher rates of kidney and bladder stones.

Marji McCullough, a nutritional scientist at the American Cancer Society, said her organization does not advise dietary supplements to prevent cancer.

"Various researchers have recommended that, but large consensus panels have not," she told Reuters Health. "There is no compelling evidence currently that taking supplements will lower your cancer risk."

The Institute of Medicine recommends that most adults get 1,000 to 1,200 milligrams (mg) of calcium per day and 600 to 800 IU of vitamin D. It sets a recommended upper limit at 2,000 mg of calcium and 4,000 IU of vitamin D.

However, Chung's team did find a small reduction in fracture risk among elderly people living in an institution such as a nursing home, with extra vitamin D and calcium preventing two out of every 100 expected fractures.

But the risk reduction was smaller for people living on their own, and might have been due to chance, she added.

Chung, who is assistant director of the Evidence-based Practice Center at Tufts, said that in an earlier report from 2009, which looked at several possible health benefits, only the fracture benefit was convincing.

Pollak said it's possible that a few people who have low levels of vitamin D may get some benefit from it, but that doesn't warrant everybody taking extra vitamins.

"You can have too much of a good thing," he told Reuters Health.

For people interested in lowering their cancer risk, he added, there are better ways to go than supplements.

"Don't smoke and stay as close as you can to your ideal body weight," Pollak urged. "Those two things will definitely lower you cancer risk and they will have many other health benefits as well -- and there are no possible downsides."

The U.S. Preventive Services Task Force could not say when its new vitamin D guidelines will be released. (Reuters)

Read more »

Posted in: HEALTH

Hong Kong school closed in bird flu scare

HONG KONG: A Hong Kong school was closed on Friday after a dead bird found in the southern Chinese city was tested positive for the deadly H5 strain of the bird flu virus, health officials said.

The closure came after the school clerk, a 48-year-old woman, picked up the sick black-headed gull at the school on Tuesday, which died the next day and was tested positive for the H5 strain, a health department spokesman told.

She picked up the bird -- a common winter visitor -- without any protection and developed a fever, sore throat and diarrhoea but has tested negative for Influenza A (H5), a variant of bird flu.

"She has been cleared in the medical results we received today but tests on her 11-year-old son are still ongoing, with results expected to be released later Friday," said the spokesman.

The secondary school in the rural New Territories, close to the border with mainland China, is closed for an unspecified time for disinfection and while the department traces people who may have had contact with the bird.

Hong Kong was the site of the world's first major outbreak of bird flu among humans in 1997, when six people died from a mutated form of the virus, which is normally confined to poultry. Millions of birds were then culled.

A 59-year-old woman tested positive for bird flu in 2010 in Hong Kong's first human case of the illness since 2003.

The city is particularly nervous about infectious diseases after an outbreak of deadly respiratory disease SARS in 2003 killed 300 people in Hong Kong and a further 500 worldwide. (AFP)

Read more »

Posted in: HEALTH