February 5th, 2010 
Children who were exposed to acetaminophen prenatally were more likely to have asthma symptoms at age five in a study of 300 African-American and Dominican Republic children living in New York City. Building on prior research showing an association between both prenatal and postnatal acetaminophen and asthma, this is the first study to demonstrate a direct link between asthma and an ability to detoxify foreign substances in the body. The findings were published this week in the journal Thorax.
The study, conducted by the Columbia Center for Children’s Environmental Health at Columbia University’s Mailman School of Public Health, found that the relationship was stronger in children with a variant of a gene, glutathione S transferase, involved in detoxification of foreign substances. The variant is common among African-American and Hispanic populations. The results suggest that less efficient detoxification is a mechanism in the association between acetaminophen and asthma.
The researchers assessed the use of analgesics during pregnancy and found that 34 percent of mothers reported acetaminophen use during pregnancy, and 27 percent of children had wheeze, an asthma-related symptom. The children whose mothers had taken acetaminophen were more likely to wheeze, visit the emergency room for respiratory problems, and develop allergy symptoms, compared to those children whose mothers did not take acetaminophen. The risk increased with increasing number of days of prenatal acetaminophen use. The children in this study live in neighborhoods of New York City that have been the hardest hit by the asthma epidemic: Northern Manhattan and the South Bronx.
Acetaminophen use among children in the U.S. has increased substantially since the early 1980s and has become increasingly common among women during pregnancy so that most women in the U.S. take acetaminophen during pregnancy. This increase coincided with a doubling of the prevalence of asthma among children in the country between 1980 and 1995.
“These findings might provide an explanation for some of the increased asthma risk in minority communities and suggest caution in the use of acetaminophen in pregnancy,” says Matthew S. Perzanowski, PhD, assistant professor of Environmental Health Sciences at the Mailman School of Public Health.
Reasons for prenatal acetaminophen use vary, but in this study population the observed associations with headaches suggest pain management as likely; however, other host factors that caused mothers to take acetaminophen and also cause asthma may explain their association. While infection is one such potential confounder, the Mailman School researchers found no association between the reported use of antibiotics and acetaminophen, and adjustment for antibiotic use during pregnancy did not affect the results.
According to the researchers, the prevalence of current wheeze diminished as the children aged, from 40 percent at age one year to 25 percent, 17 percent and 27 percent at ages two, three, and five, respectively. However, the association between prenatal acetaminophen exposure and current wheeze strengthened as the children aged.
The Columbia Center for Children’s Environmental Health study adjusted relative risks for sex, race/ethnicity, birth order, maternal asthma, maternal hardship, exposure to environmental tobacco smoke, antibiotic use and postnatal acetaminophen use.
In a similar study conducted in the UK, the frequency of acetaminophen use during pregnancy and the magnitude of association in the UK study were similar to that in New York City.
Related
- Neglecting Asthma Treatment During Pregnancy Increases Risk of Asthma in Child
Expectant mothers who eschew asthma treatment during pregnancy heighten the risk transmitting the condition to their offspring, according to one of the largest studies of its kind published in the European Respiratory Journal.
A research team from the Université de Montréal, the Hôpital du Sacré-Cœur de Montréal and Sainte-Justine University Hospital Research Center found that 32.6 percent of children born to mothers who neglected to treat their asthma during pregnancy developed the respiratory illness themselves.
“Uncontrolled maternal asthma during pregnancy could trigger a transient yet important reaction in the fetus that affects lung development and could subsequently increase the likelihood of a baby developing asthma in later childhood,” warns lead author Dr. Lucie Blais, a professor at the Université de Montréal’s Faculty of Pharmacy and researcher at the Hôpital du Sacré-Cœur de Montréal.
As part of the study, the research team examined a decade of health records for 8,226 children – from birth to 10 years of age – born to asthmatic mothers. Parents of these children were also mailed questionnaires requesting additional facts concerning familial medical history, lifestyle habits and environment.
“We found that failing to control maternal asthma during pregnancy clearly has an impact on asthma in offspring – a consequence that is independent of other contributing factors,” says Dr. Blais. “It is of great importance for physicians to adequately treat asthmatic mothers during pregnancy, not only for the favourable outcome of pregnancy but also for the benefit of the child.”
- Study Links High Stress During Pregnancy To Children’s Asthma Risk
Massachusetts researchers say stress experienced by mothers during pregnancy increases the risk their children will develop asthma.
The researchers, with Brigham and Women’s Hospital and Harvard University in Boston, looked at the differences in immune function markers in umbilical cord blood between babies born to mothers in high-stress situations and those with lower stress.
They said in a statement that they found noticeable differences in patterns that could be linked to asthma later in the children’s lives.
The researchers said their study is the first to show that increased stress in urban environments could account for the high prevalence of asthma among African-American children.
Animal studies have already suggested that a mother’s stress during pregnancy can impact children’s immune system.
The study is published in the American Thoracic Society’s American Journal of Respiratory and Critical Care Medicine.
- Smoking pregnant increases baby’s asthma risk: study
Smoking during pregancy increases the risk of a baby developing asthma up to sixfold, said a Swedish study published at the European Respiratory Society’s annual congress on Monday.
The study by Professeur Anders Bjerg of the Sunderby central hospital in Norrbotten and his specialists showed that smoking leads to babies being born underweight, a fact that has an impact on the development of asthma.
The Swedish doctors studied asthma in about 3,400 children between 1996 and 2008.
The study found that babies of smoking mothers had an average weight of 211 grammes (7.44 ounces) less than those of mothers who do not smoke.
Nearly a quarter (24.3 percent) of smoking mothers’ babies weighed less than 2.5 kilogrammes at birth against 4.1 percent for those of non-smoking women.
In underweight children of women who smoked throughout their pregnancy the asthma risk was at 23.5 percent, against 7.7 percent in children of non-smoking mothers who were born with an average weight.
- Smoking in pregnancy risks psychotic children
Mothers who smoke during pregnancy put their children at greater risk of developing psychotic symptoms as teenagers, British scientists said on Thursday.
Researchers from four British universities studied 6,356 12-year-olds and interviewed them for psychotic-like symptoms such as hallucinations or delusions. Around 19 percent had mothers who smoked during pregnancy.
Just over 11 percent, or 734 of the total group, had suspected or definite symptoms of psychosis.
Many previous studies have shown cigarettes can harm the fetuses of mothers who smoke while pregnant. The risks include causing babies to be born smaller and increasing the risk of sudden infant death syndrome or heart defects.
Stanley Zammit, a psychiatrist at Cardiff University’s School of Medicine who led the study, said the more the mothers smoked, the more likely their children were to have psychotic symptoms.
“We can estimate that about 20 percent of adolescents in this cohort would not have developed psychotic symptoms if their mothers had not smoked,” he said.
Despite countless studies flagging up the risks to babies, it is estimated that between 15 and 20 percent of women in Britain smoke during pregnancy.
The researchers also found drinking during pregnancy was associated with increased psychotic symptoms, but only in children whose mothers had drunk more than 21 units of alcohol a week in early pregnancy.
The reasons for the link between maternal smoking and psychotic symptoms are not clear, but Zammit and colleagues suggested that exposure to tobacco in the womb might affect a child’s impulsivity, attention or cognition.
Only a few mothers in the study, which was published in the British Journal of Psychiatry, said they had smoked cannabis during pregnancy, and this was not found to have any significant link with psychotic symptoms.
- Smoking in pregnancy risks psychotic children
Mothers who smoke during pregnancy put their children at greater risk of developing psychotic symptoms as teenagers, British scientists said on Thursday.
Researchers from four British universities studied 6,356 12-year-olds and interviewed them for psychotic-like symptoms such as hallucinations or delusions. Around 19 percent had mothers who smoked during pregnancy.
Just over 11 percent, or 734 of the total group, had suspected or definite symptoms of psychosis.
Many previous studies have shown cigarettes can harm the fetuses of mothers who smoke while pregnant. The risks include causing babies to be born smaller and increasing the risk of sudden infant death syndrome or heart defects.
Stanley Zammit, a psychiatrist at Cardiff University’s School of Medicine who led the study, said the more the mothers smoked, the more likely their children were to have psychotic symptoms.
“We can estimate that about 20 percent of adolescents in this cohort would not have developed psychotic symptoms if their mothers had not smoked,” he said.
Despite countless studies flagging up the risks to babies, it is estimated that between 15 and 20 percent of women in Britain smoke during pregnancy.
The researchers also found drinking during pregnancy was associated with increased psychotic symptoms, but only in children whose mothers had drunk more than 21 units of alcohol a week in early pregnancy.
The reasons for the link between maternal smoking and psychotic symptoms are not clear, but Zammit and colleagues suggested that exposure to tobacco in the womb might affect a child’s impulsivity, attention or cognition.
Only a few mothers in the study, which was published in the British Journal of Psychiatry, said they had smoked cannabis during pregnancy, and this was not found to have any significant link with psychotic symptoms.
