A new study discovers children whose mothers had a severe form of a morning sickness during pregnancy were 53 percent more likely to be diagnosed with autism spectrum disorder. Kaiser Permanente researchers said the condition, known as hyperemesis gravidarum, is rare and occurs in less that 5 percent of all pregnancies.
Nevertheless, researchers believe the findings are important because the research suggests that children born to women with hyperemesis may be at an increased risk of autism. “Awareness of this association may create the opportunity for earlier diagnosis and intervention in children at risk of autism,” explains lead study author Darios Getahun, M.D., Ph.D., of Kaiser Permanente Southern California Department of Research and Evaluation.
The study appears in the American Journal of Perinatology.
Experts explain that women with the severe form of morning sickness experience intense nausea and are unable to keep down food and fluids. This can lead to dangerous dehydration and inadequate nutrition during pregnancy.
To determine the extent of the association between hyperemesis gravidarum and autism spectrum disorder, researchers reviewed electronic health records of nearly 500,000 pregnant women and their children born between 1991 and 2014 at Kaiser Permanente in Southern California. They compared children whose mothers had a diagnosis of hyperemesis gravidarum during pregnancy to those whose mothers did not.
Other findings from the research included:
• Exposure to hyperemesis gravidarum was associated with increased risk of autism when hyperemesis gravidarum was diagnosed during the first and second trimesters of pregnancy, but not when it was diagnosed only in the third trimester;
• Exposure to hyperemesis gravidarum was associated with risk of autism regardless of the severity of the mother’s hyperemesis gravidarum;
• The association between hyperemesis gravidarum and autism spectrum disorder was stronger in girls than boys and among whites and Hispanics than among blacks and Pacific Islanders;
• The medications used to treat hyperemesis gravidarum did not appear to be related to autism risk.
Investigators explain that the results are consistent with the hypothesis that women experiencing hyperemesis gravidarum have poor nutritional intake. This may, in turn lead to potential long-term neurodevelopment impairment in their children.
The study cannot, however, rule out other possible explanations, such as perinatal exposures to some medications and maternal smoking.
Source: Kaiser Permanente/EurekAlert
A new Swedish study suggests anemia early in pregnancy may increase the risk of autism, ADHD and intellectual disability in children. Anemia is a common condition in late pregnancy and researchers discovered anemia toward the end of pregnancy did not have the same correlation.
The findings, published in JAMA Psychiatry, underscore the importance of early screening for iron status and nutrition counseling.
An estimated 15-20% of pregnant women worldwide suffer from iron deficiency anemia — lower blood oxygen levels due to a lack of iron. By the third trimester, pregnant women have nearly 50% more blood than they did pre-pregnancy in order to provide enough oxygen for both the woman and the fetus, and their iron requirements are nearly double that of nonpregnant women. Thus, the vast majority of anemia diagnoses are made toward the end of pregnancy, when blood levels are at their highest.
In the current study, the researchers examined what impact the timing of an anemia diagnosis had on the fetus’ neurodevelopment. Investigators specifically assessed if there was an association between an earlier diagnosis in the mother and the risk of intellectual disability (ID), autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) in the child.
Overall, very few women are diagnosed with anemia early in pregnancy. In this study of nearly 300,000 mothers and more than half a million children born in Sweden between 1987-2010, less than 1% of all mothers were diagnosed with anemia before the 31st week of pregnancy. Among the 5.8% of mothers who were diagnosed with anemia, only 5% received their diagnosis early on.
The researchers found that children born to mothers with anemia diagnosed before the 31st week of pregnancy had a somewhat higher risk of developing autism and ADHD and a significantly higher risk of intellectual disability compared to healthy mothers and mothers diagnosed with anemia later in pregnancy.
Among the early anemic mothers, 4.9% of the children were diagnosed with autism compared to 3.5% of children born to non-anemic mothers, 9.3% were diagnosed with ADHD compared to 7.1%, and 3.1% were diagnosed with intellectual disability compared to 1.3%.
After considering other factors such as income level and maternal age, the researchers concluded that the risk of autism in children born to mothers with early anemia was 44% higher compared to children with non-anemic mothers. The risk of ADHD was 37% higher and the risk of intellectual disability was 120% higher.
Even when compared to their siblings, children exposed to early maternal anemia were at higher risk of autism and intellectual disability. Importantly, anemia diagnosed after the 30th week of pregnancy was not associated with a higher risk for any of these conditions.
“A diagnosis of anemia earlier in pregnancy might represent a more severe and long-lasting nutrition deficiency for the fetus,” says Renee Gardner, project coordinator at the Department of Public Health Sciences at Karolinska Institutet and the study’s lead researcher.
“Different parts of the brain and nervous system develop at different times during pregnancy, so an earlier exposure to anemia might affect the brain differently compared to a later exposure.”
The researchers also noted that early anemia diagnoses were associated with infants being born small for gestational age while later anemia diagnoses were associated with infants being born large for gestational age.
Babies born to mothers with late-stage anemia are typically born with a good iron supply, unlike babies born to mothers with early anemia.
Although researchers could not specify whether iron deficiency anemia is more detrimental than anemia caused by other factors, iron deficiency is by far the most common cause of anemia. Investigators say the findings may thus support regular iron supplementation in maternity care.
Scientists emphasize the importance of early screening for iron status and nutrition counseling but note that more research is needed to find out if early maternal iron supplementation could help reduce the risk of neurodevelopmental disorders in children.
Adult women 19 to 50 years old typically need 18 mg of iron per day, though needs increase during pregnancy. Since excessive iron intake can be toxic, pregnant women should discuss their iron intake with their midwife or doctor.
Autism rates among racial minorities in the U.S. have spiked in recent years, with black rates now exceeding those of whites in most states and Hispanic rates increasing faster than any other group, according to a new study published in the Journal of Autism and Developmental Disorders.
The researchers from the University of Colorado Boulder also found that the prevalence of autism among white youth is ticking up again, after flattening in the mid-2000s.
Although some of the increases are due to more awareness and better detection among minority groups, other environmental factors are likely at play, the authors conclude.
“We found that rates among blacks and Hispanics are not only catching up to those of whites — which have historically been higher — but surpassing them,” said lead author Dr. Cynthia Nevison, an atmospheric research scientist with the Institute of Arctic and Alpine Research.
“These results suggest that additional factors beyond just catch-up may be involved.”
For the study, Nevison worked with co-author Dr. Walter Zahorodny, an autism researcher and associate professor of pediatrics at Rutgers New Jersey Medical School, to analyze the most recent data available from the Individuals with Disabilities Education Act (IDEA) and the Autism and Developmental Disabilities Monitoring (ADDM) Network.
IDEA tracks prevalence, including information on race, among 3-to-5-year-olds across all 50 states annually. ADDM tracks prevalence among 8-year-olds in 11 states every two years.
The findings show that between birth year 2007 and 2013, autism rates among Hispanic children, ages 3 to 5, rose 73%, while rates among blacks rose 44% and rates among whites rose 25%.
In 30 states, prevalence among blacks was higher than among whites by 2012.
In states with “high prevalence,” 1 in 79 whites, 1 in 68 blacks and 1 in 83 Hispanics born in 2013 had been diagnosed with autism between ages 3 and 5.
Other states, including Colorado, fell in a “low-prevalence” category, but the authors warn that the differences between states likely reflect differences in how well cases are reported in preschool-age children. They also said the real prevalence is substantially higher, as many children are not diagnosed until later in life.
“There is no doubt that autism prevalence has increased significantly over the past 10 to 20 years, and based on what we have seen from this larger, more recent dataset it will continue to increase among all race and ethnicity groups in the coming years,” said Zahorodny.
In 2018, the Centers for Disease Control reported that about 1 in 59 children of all races have been diagnosed with autism and that rates had risen 15 percent overall from the previous two year period, largely due to better outreach and diagnosis among historically underdiagnosed minority populations.
“Our data contradict the assertion that these increases are mainly due to better awareness among minority children,” said Zahorodny. “If the minority rates are exceeding the white rates that implies some difference in risk factor, either greater exposure to something in the environment or another trigger.”
Risk factors associated with autism include advanced parental age, challenges to the immune system during pregnancy, genetic mutations, premature birth and being a twin or multiple.
The authors said that, based on current research, they cannot determine what other environmental factors might be playing into the higher rates, but they would like to see more work done in the field.
Source: University of Colorado Boulder
Autism diagnoses are on the rise worldwide. In the U.S., the prevalence of autism has increased from 0.05 percent in 1966 to more than 2 percent today. In Quebec, the reported prevalence is close to 2 percent, and according to a paper issued by the province’s public health department, the prevalence in Montérégie has increased by 24% annually since 2000.
However, Dr. Laurent Mottron, a psychology professor from the Université de Montréal, has serious reservations about these numbers.
After researching autism data, he and his team found that the differences between people diagnosed with autism and the rest of the population is actually shrinking.
Their findings are published in the journal JAMA Psychiatry.
Mottron worked with an international research team from France, Denmark and Montreal to review 11 large analyses published between 1966 and 2019, with data drawn from nearly 23,000 people with autism.
The analyses reveal that individuals with autism and those in the general population show significant differences in seven areas: emotion recognition, theory of mind (ability to understand that other people have their own intentions), cognitive flexibility (ability to transition from one task to another), activity planning, inhibition, evoked responses (the nervous system’s response to sensory stimulation) and brain volume.
Together, these measurements cover the basic psychological and neurological components of autism.
The team examined the “effect size” — the size of the differences observed between people with autism and those without it — and compared its progression over the years.
They found that, in each of the seven areas, the measurable differences between people with autism and those without it has decreased over the past 50 years. In fact, a statistically significant dilution in effect size (ranging from 45% to 80%) was noted in five of these seven areas.
The only two measurements that didn’t show significant dilution were inhibition and cognitive flexibility.
“This means that, across all disciplines, the people with or without autism who are being included in studies are increasingly similar,” said Mottron.
“If this trend holds, the objective difference between people with autism and the general population will disappear in less than 10 years. The definition of autism may get too blurry to be meaningful — trivializing the condition — because we are increasingly applying the diagnosis to people whose differences from the general population are less pronounced.”
To verify that the trend was unique to autism, the team also studied data on similar areas from schizophrenia studies. They found that the prevalence of schizophrenia has stayed the same and the difference between people with schizophrenia and those without it is increasing.
The diagnostic guidelines for autism haven’t changed over the years, so this wasn’t the cause. Instead, Mottron believes that what has changed are diagnostic practices.
“Three of the criteria for an autism diagnosis are related to sociability,” he said. “Fifty years ago, one sign of autism was a lack of apparent interest in others. Nowadays, it’s simply having fewer friends than others. Interest in others can be measured in various ways, such as making eye contact. But shyness, not autism, can prevent some people from looking at others.”
To complicate matters, the term “autism” has fallen out of favor, replaced by “autism spectrum disorder,” a sign that there’s a new belief that there are various forms of the condition. This has prompted some people to question whether autism exists at all.
“And yet, autism is a distinct condition,” says Mottron. “Our study shows that changes in diagnostic practices, which have led to a false increase in prevalence, are what’s fuelling theories that autism doesn’t really exist.”
Even though Mottron recognizes that there is a continuum between people with autism and those without it, he believes that such a continuum could result from the juxtaposition of natural categories.
“Autism is a natural category at one end of the socialization continuum. And we need to focus on this extreme if want to make progress,” he said.
In his opinion, autism studies include too many participants who aren’t sufficiently different from people without autism.
In contrast to the prevailing scientific belief, Mottron thinks that including more subjects in studies on autism, as it is currently defined, lowers the odds of discovering new things about the mechanisms of the disorder. No major discoveries have been made in this field in the last 10 years.
Source: Université de Montréal
A new Swedish study suggests children with inflammatory bowel disease (IBD) have a greater risk for psychiatric disorders. Researchers believe that more psychological support and longer follow-up is needed for the children affected and their parents.
Investigators explain that it is already known that adults with IBD (ulcerative colitis or Crohn’s disease) run an increased risk of psychiatric disorders. Now their new study shows that children with IBD also run a higher risk of mental health problems.
The research by investigators at the Karolinska Institutet in Sweden appears in JAMA Pediatrics.
For the study, Karolinska scientists assessed more than 6,400 children with IBD, born between 1973 and 2013. Using population registers, the researchers compared the risk of psychiatric disorders later on in life with both healthy children from the general population and with the patients’ own siblings.
Investigators believe the study methodology which compared patients with their siblings, allowed precise analysis of a large number of so-called confounders. Confounders such as socioeconomics, lifestyle and heredity are factors that are known to affect the risk of psychiatric disorders in children.
During an average follow-up period of 9 years, approximately 17 percent of the children with IBD were given a psychiatric diagnosis compared with just under 12 percent of the healthy children and about 10 percent of the siblings.
This means that the risk of psychiatric disorders was 1.6 times higher in children with IBD compared to Swedish children from general population. Likewise, the risk for the children with IBD was greater than for their siblings.
The higher risk applied to a number of psychiatric diagnoses such as depression, anxiety, eating disorders, personality disorders, ADHD and autism spectrum disorder. There was also a higher risk of suicide attempt after reaching adulthood.
“The study shows that children with IBD and their parents are in need of psychological support and longer follow-up,” said Dr. Agnieszka Butwicka, a researcher at the Department of Medical Epidemiology and Biostatistics, Karolinska Institutet.
“Special help could be offered to children who become ill at a young age and to children of parents with mental health problems.”
Investigators discovered the risk of mental health problems was greatest during the first year with IBD. The risk was particularly high for children who were diagnosed with IBD before the age of 6 years and for children of parents with psychiatric disorders.
However, although the study is an observation study an absolute link cannot be identified with certainty. Nevertheless, the results do indicate that IBD contributes to mental health problems.
“Because the risk for these children is higher compared with their own siblings, it is likely that it is IBD affecting their mental health rather than other factors such as socioeconomics, lifestyle or heredity in the family,” said Dr. Jonas F. Ludvigsson, a professor in the Department of Medical Epidemiology and Biostatistics.
Source: Karolinska Institute
The evidence is clear that couples are waiting to have children at a later age. While some studies suggest a link between a father’s age and a mental health diagnosis among offspring, a new Dutch study considered the behavior problems of children born to older parents among a general population.
Specifically, researchers looked at externalizing behaviors (e.g., aggression) and internalizing behaviors (e.g., anxiety, depression) of children born to older parents when the youth were 10 to 12 years old.
Investigators discovered that children of older parents tend to have fewer externalizing behavior problems than children of younger parents. The researchers also found that parents’ age was unrelated to children’s internalizing behaviors.
The study was done by researchers at Utrecht University, Vrije Universiteit Amsterdam, Erasmus Medical Center, and University Medical Center Groningen. The study appears in Child Development, a journal of the Society for Research in Child Development.
“Evidence points to an association between fathers’ age and autism spectrum disorders and schizophrenia, so we wanted to know if there is an association in the general population between parents’ age and common behavior problems in children, beyond the clinical diagnoses,” said study leader Dr. Marielle Zondervan-Zwijnenburg, a postdoctoral researcher at Utrecht University.
“With respect to common behavior problems, we found no reason for future parents to worry about a harmful effect of having a child at an older age.”
Researchers analyzed the problem behavior of 32,892 Dutch children when they were 10 to 12 years old. Problem behavior was rated by fathers, mothers, teachers, and the children themselves through a series of standardized instruments.
The children, all of whom were born after 1980, were part of four studies: Generation R, the Netherlands Twin Register, the Research on Adolescent Development and Relationships-Young Cohort (RADAR-Y), and the Tracking Adolescents’ Individual Lives Survey.
The children represented the entire Dutch geographic region across all strata of society and a range of socioeconomic statuses.
In the Generation R study, mothers’ age at child’s birth ranged from 16 to 46 and fathers’ age at child’s birth ranged from 17 to 68. In the Netherlands Twin Register, mothers’ age at child’s birth ranged from 17 to 47 and fathers’ from 18 to 63.
In the RADAR-Y study, mothers’ age at child’s birth ranged from 17 to 48 and fathers’ from 20 to 52. And in the Tracking Adolescents’ Individual Lives Survey, mothers’ age at child’s birth ranged from 16 to 44 and fathers’ from 18 to 52.
Investigators discovered that the children of older parents had fewer externalizing behavior problems, as reported by the parents.
The findings of fewer externalizing behavior problems persisted —as reported by parents and teachers — even after considering the families’ socioeconomic status. Therefore, researchers believe the favorable effect of parents’ age on children’s behavior was not solely due to their income level.
The study also found that parents’ age appeared unrelated to children’s internalizing behavior problems.
Investigators note that they focused only on children’s externalizing and internalizing behavior problems, so the findings cannot be generalized to other behaviors. However, they are extending their research to cognition and attention problems.
In addition, the researchers assessed children’s behavior problems during early adolescence; they plan to extend their work to other points in development.
“It’s possible that some of the reason why older parents have children with fewer problems like aggression is that older parents have more resources and higher levels of education,” said Dr. Dorret Boomsma, a professor at Vrije Universiteit Amsterdam and a study coauthor.
“But it is important to note that the higher average educational level of older parents does not completely explain the decreased levels of externalizing problems in their children.”
Source: Society for Research in Child Development