Effects of TV, Drug Exposures in Early Life May Be Long-Lasting
MONDAY May 3, 2010 -- A group of new studies demonstrate just how critical prenatal, maternal and environmental factors can be in shaping children's later health, both emotional and physical.
Among other things, the studies found that kids who stayed glued to a TV screen too long or were born to moms who smoked or took antidepressants during pregnancy had raised risks for behavioral and other problems later on in life.
"Early childhood is critical for the development of a multitude of skills," noted Richard E. A. Loren, clinical director of the Center for ADHD and assistant professor of clinical pediatrics at the University of Cincinnati College of Medicine. "It's not set in stone but certainly children that do better in early years continue to do better, and children who get behind have to work harder to get caught up -- and some don't."
"We're learning how many critical variables [have an] impact on this period of prenatal development and postnatal behavior," added Dr. Kathryn J. Kotrla, associate dean and chairwoman of psychiatry and behavioral science at Texas A& M Health Science Center College of Medicine Round Rock campus.
The reports appear in the May issue of Archives of Pediatrics & Adolescent Medicine.
In one study, researchers at the University of Montreal assessed how much TV children were watching at age 2-1/2 years, then correlated that with behavior and health in the fourth grade.
Each additional hour watching TV was linked with declines in classroom engagement, math achievement (though not reading), and physical activity, as well as increases in soft drink and snack consumption, body mass index, and the tendency to be bullied by classmates.
Disturbingly, Loren pointed out, many of the children were actually watching TV at rates below those recommended by the American Academy of Pediatrics (which is no TV till age 2, then no more than 2 hours of "quality programming" a day).
"Yet they still found significant impacts on later functioning, which makes me think that maybe the recommendations need to be pulled up to no TV under the age of 3 or 4," he said.
The second study found that pregnant mom's use of antidepressants called SSRIs [selective serotonin reuptake inhibitors, such as Paxil, Prozac or Zoloft] as well as mothers' moods when the child was 3 correlated to anxious and depressive behavior in those young children.
"This doesn't mean that all children exposed to SSRIs while still in the womb are at an increased risk, only that some exposed children are, and at this point we don't know why," said study lead author Dr. Tim Oberlander, professor of developmental pediatrics at the University of British Columbia in Vancouver. "None of which is to say that pregnant women should not be treated for depression. All mothers need to be treated -- just we have a lot to learn about who can benefit from pharmacological treatment with an SSRI."
"Given that we know that early exposure to stressful life experiences can set up a life time risk for poor mental health, our findings should also remind us that one of our greatest public health challenges remains the need to find ways to reduce early life stress," he added. "Just like we can vaccinate against infectious illnesses, why can't we 'inoculate' children against adverse effects of early life stress?"
Another study found that prenatal exposure to nicotine - although not to cocaine, opiates, marijuana or alcohol - was associated with sleep problems during the first 12 years of the child's life.
"Together, the two studies [on SSRIs and nicotine] suggest continued focus on the complexity of maternal-child bonding and interactions," Kotrla said. "Identifying concrete risk factors -- nicotine, [genetic] variations, etc. -- helps shape and define interventions targeted towards childhood emotional disturbances."
Finally, a study conducted by researchers at Hadassah Hebrew University Hospital in Jerusalem found that, among twins, the twin who weighed more at birth was more likely to have behavioral problems at 3 or 4 years of age.
Visit the American Academy on Pediatrics for more on child development.
Posted: May 2010