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From NPR:

More Hints That Dad's Age At Conception Helps Shape A Child's Brain

Traditionally, research has focused on women's "biological clock." But in recent years, scientists have been looking more and more at how the father's age at conception might affect the baby, too. A study published Wednesday hints that age really might matter — in terms of the child's mental health.

Researchers from the University of Indiana and the Karolinska Institute found that compared with children fathered by men who were 20-24 years old, kids born to dads who were 45 or older were three times as likely to have autism and 13 times as likely to have ADHD. Kids born to older dads were also more likely to go on to develop substance abuse problems and get lower grades in school. The findings appear in JAMA Psychiatry.

To figure out how paternal age was related to children's psychiatric health, the researchers looked at millions of parents in Sweden who had children between 1973 and 2001. The researchers took into account the mother's age, as well as other demographic factors that might play a role in the child's cognitive development and mental health.

"There's a growing body of literature that suggests that advancing paternal age is associated with a host of problems," D'Onofrio tells Shots. Another study, published in JAMA Psychiatrylast month, found that the children of older fathers seemed to be at greater risk for developing schizophrenia and autism.

D'Onofrio and his colleagues paid special attention to siblings and cousins, and found that even among kids in the same extended family, a dad's age when his child was born made a difference.

The results are in line with a growing body of research linking older fatherhood with various developmental problems in children.

However, the study looks only at how paternal age and children's mental health are associated — it's a correlation, Reichenberg cautions, not a proven causal link. Scientists haven't yet determined the mechanisms of the effect. But it doesn't seem to be simply a matter of overdiagnosis among the children of older parents, the scientists say. Other research has found that as men get older, their sperm cells are more likely to contain random mutations that might, theoretically, contribute to disorders like autism in their kids.

Ultimately, men and women of all ages, he says, should remember that age is only one of many factors influencing the developing baby's health.

"The most important thing is [that] future mothers and fathers should still go ahead and have children, even if the father is older than 45 or 50," Reichenberg says. "Most of these children will be absolutely fine."

Acetaminophen was the one nonprescription medication that for decades pregnant women thought was safe to take. Looks like not any more - a study found that taking acetaminophen during pregnancy was associated with hyperkinetic disorder and ADHD at age 7. And the longer it was taken during pregnancy, the stronger the association. From Science Daily:

Use of acetaminophen during pregnancy linked to ADHD in children, researchers say

Acetaminophen, found in over-the-counter products such as Excedrin and Tylenol, provides many people with relief from headaches and sore muscles. When used appropriately, it is considered mostly harmless. Over recent decades, the drug, which has been marketed since the 1950s, has become the medication most commonly used by pregnant women for fevers and pain.

In a report in the current online edition of JAMA Pediatrics,researchers from the UCLA Fielding School of Public Health show that taking acetaminophen during pregnancy is associated with a higher risk in children of attention-deficity/hyperactivity disorder and hyperkinetic disorder. The data raises the question of whether the drug should be considered safe for use by pregnant women.

ADHD, one of the most common neurobehavioral disorders worldwide, is characterized by inattention, hyperactivity, increased impulsivity, and motivational and emotional dysregulation. Hyperkinetic disorder is a particularly severe form of ADHD.

The UCLA researchers used the Danish National Birth Cohort, a nationwide study of pregnancies and children, to examine pregnancy complications and diseases in offspring as a function of factors operating in early life. The cohort focuses especially on the side effects of medications and infections. The researchers studied 64,322 children and mothers who were enrolled in the Danish cohort from 1996 to 2002. 

More than half of all the mothers reported using acetaminophen while pregnant. The researchers found that children whose mothers used acetaminophen during pregnancy were at a 13 percent to 37 percent higher risk of later receiving a hospital diagnosis of hyperkinetic disorder, being treated with ADHD medications or having ADHD-like behaviors at age 7. The longer acetaminophen was taken -- that is, into the second and third trimesters -- the stronger the associations. The risks for hyperkinetic disorder/ADHD in children were elevated 50 percent or more when the mothers had used the common painkiller for more than 20 weeks in pregnancy.

"It's known from animal data that acetaminophen is a hormone disruptor, and abnormal hormonal exposures in pregnancy may influence fetal brain development," Ritz said. Acetaminophen can cross the placental barrier, Ritz noted, and it is plausible that acetaminophen may interrupt fetal brain development by interfering with maternal hormones or through neurotoxicity, such as the induction of oxidative stress, which can cause the death of neurons.

From Science Daily:

Impact of repetitive heading in soccer needs more research, say experts

Soccer is the most-popular and fastest-growing sport in the world and, like many contact sports, players are at risk of suffering concussions from collisions on the field. But researchers warned in a paper published today that not enough attention has been given to the unique aspect of soccer -- the purposeful use of the head to control the ball -- and the long-term consequences of repetitive heading.

The literature review by Dr. Tom Schweizer, director of the Neuroscience Research Program of St. Michael's Hospital, was published in the journal Brain Injury.

More than 265 million people play soccer worldwide, including 27 million in North America. Due to the nature of the sport, players are particularly vulnerable to head and neck injuries. Most are caused by unintentional or unexpected contact, such as when a player collides with teammates, opponents or the playing surface.

There is significant concern in the sporting and medical worlds about the potential long-term cognitive and behavioral consequences for athletes who suffer acute or repeat concussions or multiple "sub-concussive" head impacts -- blows to the head not causing symptoms of concussions.

"The practice of heading, which might occur thousands of times over a player's career, carries unknown risks, but may uniquely contribute to cognitive decline or impairment in the short- or long-term," said Dr. Schweizer, a neuroscientist. "Thus, soccer players present a unique opportunity to study whether cumulative sub-concussive impacts affect cognitive functioning, similar to that of concussions."

Research papers that looked at the mechanism of injury found 41.1 per cent of concussions resulted from contact by an elbow, arm or hand to the head. One found that 58.3 per cent of concussions occurred during a heading duel. More females suffered concussions from player-to-surface and player-to-ball contact than males who had more player-to-player contact than females.

Studies on the long-term effects of heading found greater memory, planning and perceptual deficits in forwards and defenders, players who execute more headers. One study found professional players reporting the highest prevalence of heading during their careers did poorest in tests of verbal and visual memory as well as attention. Another found older or retired soccer players were significantly impaired in conceptual thinking, reaction time and concentration. The few studies that used advanced imaging techniques found physical changes to the brains in players who had concussions.

Children's brain development being harmed by chemicals in the environment - both before birth and in childhood -  is such an important topic that here are excerpts from two articles about the same report that was just released (in Lancet Neurology).  From Time:

Children Exposed to More Brain-Harming Chemicals Than Ever Before

In recent years, the prevalence of developmental disorders such as autism, attention deficit/hyperactivity disorder (ADHD) and dyslexia  have soared. While greater awareness and more sophisticated diagnoses are partly responsible for the rise, researchers say the changing environment in which youngsters grow up may also be playing a role.

In 2006, scientists from the Harvard School of Public Health and the Icahn School of Medicine at Mount Sinai identified five industrial chemicals responsible for causing harm to the brain — lead, methylmercury, polychlorinated biphenyls (found in electric transformers, motors and capacitors), arsenic (found in soil and water as well as in wood preservatives and pesticides) and toluene (used in processing gasoline as well as in paint thinner, fingernail polish and leather tanning). Exposure to these neurotoxins was associated with changes in neuron development in the fetus as well as among infants, and with lower school performance, delinquent behavior, neurological abnormalities and reduced IQ in school-age children.

Now the same researchers have reviewed the literature and found six additional industrial chemicals that can hamper normal brain development. These are manganese, fluoride, chlorpyrifos, dichlorodiphenyltrichloroethane, tetrachloroethylene and polybrominated diphenyl ethers. Manganese, they say, is found in drinking water and can contribute to lower math scores and heightened hyperactivity, while exposure to high levels of fluoride from drinking water can contribute to a seven-point drop in IQ on average. The remaining chemicals, which are found in solvents and pesticides, have been linked to deficits in social development and increased aggressive behaviors.

But they say the growing body of research that is finding links between higher levels of these chemicals in expectant mothers’ blood and urine and brain disorders in their children should raise alarms about how damaging these chemicals can be. The developing brain in particular, they say, is vulnerable to the effects of these chemicals, and in many cases, the changes they trigger are permanent. The consequence of such brain damage is impaired [central nervous system] function that lasts a lifetime and might result in reduced intelligence, as expressed in terms of lost IQ points, or disruption in behavior,” they write in their report, which was published in the journal Lancet Neurology.

Same report, from Science Daily: Growing number of chemicals linked with brain disorders in children

"The greatest concern is the large numbers of children who are affected by toxic damage to brain development in the absence of a formal diagnosis. They suffer reduced attention span, delayed development, and poor school performance. Industrial chemicals are now emerging as likely causes," said Philippe Grandjean, adjunct professor of environmental health at HSPH.

The study outlines possible links between these newly recognized neurotoxicants and negative health effects on children, including:  - Manganese is associated with diminished intellectual function and impaired motor skills  - Solvents are linked to hyperactivity and aggressive behavior - Certain types of pesticides may cause cognitive delays.

Grandjean and co-author Philip Landrigan, Dean for Global Health at Mount Sinai, also forecast that many more chemicals than the known dozen or so identified as neurotoxicants contribute to a "silent pandemic" of neurobehavioral deficits that is eroding intelligence, disrupting behaviors, and damaging societies. But controlling this pandemic is difficult because of a scarcity of data to guide prevention and the huge amount of proof needed for government regulation. "Very few chemicals have been regulated as a result of developmental neurotoxicity," they write.

The authors say it's crucial to control the use of these chemicals to protect children's brain development worldwide. They propose mandatory testing of industrial chemicals and the formation of a new international clearinghouse to evaluate industrial chemicals for potential developmental neurotoxicity.

Take note: all of us are exposed to these contaminants because they are in our environment.  The Inuit exposure is just more concentrated. From Feb. 7, 2014 Environmental Health News:

Contaminants have variety of effects on Arctic baby IQs

Babies in Arctic Canada are at risk of specific effects on their mental abilities, depending on which contaminants they are exposed to in the womb, according to a new study.While lead, methylmercury and polychlorinated biphenyls (PCBs) all are linked to neurological effects, each seems to have a different effect on infants, the scientists concluded. For example, PCBs seemed to impair the babies’ ability to recognize things they have seen.

The study involved 94 Inuit infants and their mothers from Nunavik, in northern Quebec. PCBs, mercury and other pollutants hitchhike north via prevailing winds and currents from industrialized areas, and then accumulate in food webs, predominantly in the eastern Arctic. Because the Inuit in Canada and Greenland eat top predators such as beluga whales and seals, they are among the world’s most contaminated human beings. The scientists measured the babies’ prenatal exposure to the three contaminants by testing cord blood, and then administered standard mental development tests at 6.5 months and 11 months. 

“Each contaminant was independently associated with impairment of distinct aspects of cognitive function with long-term implications for cognitive development PCBs with visual recognition memory, methylmercury with working memory and an early precursor of executive function, lead with processing speed – deficits that can already be detected during the first year of life,” the authors wrote.

For the research, scientists at Quebec’s Centre de Recherche du CHUQ, who have been studying effects of contaminants on Inuit children for two decades, teamed up with Wayne State University scientists who conducted groundbreaking work in the Great Lakes linking PCBs to reduced IQs in the 1990s.

From the Medical Daily:

High Blood Pressure In Teens, Young Adults A Sign Of Hardened Arteries Down The Road

Your blood pressure during your teens and early twenties, though often naturally low due to youth, may have something to do with your cardiovascular health in later years, according to new research from Northwestern University Feinberg School of Medicine. In the new study, which was published in JAMA, researchers found that having higher blood pressure during your teens and twenties was actually linked to hardened arteries at age 40.

The study, led by epidemiologist Norrina Allen, points out the significance of maintaining cardiovascular health at a young age.

The study reviewed 4,600 men and women throughout several different states and followed them for 25 years. They found that 19 percent of them had blood pressure that was much higher than their peers, and that another 5 percent started with high blood pressure that gradually rose. Though these blood pressure readings fell within “normal” range for their age, it was higher than average and thus they were more likely to develop hypertension by age 40. Hypertension is also known as high blood pressure or arterial hypertension.

“While you wouldn’t prescribe medications for this group, you might have conversations with those individuals about ways they can improve their diet or increase physical activity,” Allen told NPR. She notes that “many of these cardiovascular risk factors are cumulative,” meaning they often occur over a long period of time and are a combination of things, from smoking to living a sedentary lifestyle.

From Science Daily:

Overweight or obese people breathe more air pollutants

Overweight or obese adults can breathe 7-50% more air per day than an adult with healthy weight does, which makes them more vulnerable to air contaminants causing asthma and other pulmonary diseases, according to a study by Dr. Pierre Brochu, a professor at Université de Montréal's School of Public Health. For overweight or obese children, daily inhalation rates are 10-24% higher than for normal weight children.

Study based on more than 1,900 participants: Brochu's study is based on an analysis of data from 1,069 participants aged 5-96 years, compared with data collected from 902 normal weight people (in a study conducted by Dr. Brochu in 2011). Data were analyzed, among other things, according to participant age and gender. Adults were also classified according to their body mass index

The situation for obese children may be even more worrisome, according to the data analyzed by Dr. Brochu. In fact, because of their much higher metabolism -- in relation to their low body weight -- they breathe more air per kilogram of weight than obese adults do to maintain their basic functions and perform their daily activities. The same trend applies to men compared to women. "It remains to be seen if high inhalation rates are a factor in the development of asthma and other lung diseases in adults and children," said Dr. Brochu, who hopes to eventually validate this hypothesis.