Studies About High Cortisol Level and Its Effects UPDATED
Dr. Gunnar has been studying emotional and social processes that regulate physiological responses to stressful events early in childhood especially surrounding the adrenocortical system and cortisol especially in internationally adopted children. See a list of her work here. Her work is often cited in adoption research articles.
Many adoptive parents report that their child’s history includes preterm birth. University of Rhode Island Professor of Nursing Mary C. Sullivan has been studying various effects on preterm infants for over twenty years. A new study of hers was discussed in June 2011 in Science Daily.
“The latest investigation, funded by a $2.4 million National Institutes of Health grant to URI, is examining whether stresses experienced by pre-term babies lead to illnesses when they are adults.
In March, Sullivan presented her early findings at the Eastern Nursing Research Society in Philadelphia. Sullivan’s co-investigator, cardiologist Jim Zeigler, will present their findings at the 27th Congress meeting of the European Group of Pediatric Work Physiology at Britain’s University of Exeter Sept. 19 — 23.
Her latest work is based on the “fetal origins hypothesis,” which states that the stress response of pre-term infants, called the hypothalamic-pituitary adrenal (HPA) axis, is a mechanism underlying fetal origins of adult chronic diseases.
Pre-term birth sets up a stress response, which produces higher levels of the hormone cortisol, which is essential for regulating metabolism, immune response, vascular tone and homeostasis, Sullivan said.
Her research is comparing cortisol levels in the adults who were born pre-term versus those born full-term and is assessing if cortisol levels among adults who were the sickest as premature infants are higher than those less medically and neurologically compromised.
Very low birth weight, repeated blood draws, surgery and breathing issues are among the major factors in stress levels for pre-term infants.
Among the early findings are:
- Male gender and birth weight affect early adult pulmonary function.
- The poorest pulmonary outcomes and higher resting blood pressure were for those born at extremely low birth weight.
- Additional health data for age 23 years has not been analyzed yet, but data from age 17 revealed that physical health, growth, and subtle neurological outcomes were poorer in the preterm groups.
- Infants with medical and neurological impacts had a 24 to 32 percent increase in acute and chronic health conditions.
- Continued monitoring of adults born prematurely is warranted, not only during young adulthood but as they reach middle age.
Sullivan said one approach her team will undertake will be Pathobiological Determinants of Atherosclerosis in Youth (PDAY) Risk Score at age 23 because it is strongly associated with coronary artery disease 10 to 15 years later.
“Continued monitoring of preterm survivors will enhance our understanding of the relative impact of prematurity and neonatal intensive care on later adult cardiopulmonary disease,” Sullivan said.
“Since the beginning of the study, we have been asking the questions, can babies self-right themselves and do they have a resiliency that helps them overcome the challenges of pre-term birth?” Sullivan said. “Are there protective factors in the environment that mitigate the effects?”
Pre-term birth also affects even those infants not medically and neurologically ill in the following ways:
- Effects of pre-term birth do not disappear after age 2 or even after pre-term children catch up physically with full-term babies.
- Learning disabilities and other functioning issues often do not appear in premature babies until second grade and middle school years.
- Pre-term infants with no medical conditions have more learning disabilities, struggles with mathematics and need more school services than full-term babies. One of Sullivan’s studies determined that at least one-third of babies born pre-term needed school services at some point during their education. Out of that group, 22 percent of the healthy pre-term babies received school services. Almost one quarter of this group had an Individualized Education Plan (special education plan governed by federal and state law), with 15 percent receiving resources, 7 percent in self-contained classroom settings, and 11 percent receiving speech and language services.
- Some children of pre-term birth are less coordinated, which may be related to brain development and effects of neonatal intensive care.
- They have fewer friends and boys have more difficulty in school.
On the positive side, Sullivan found:
- Children who were born pre-term have a persistent drive to succeed.
- Children whose mothers provided a nurturing environment and who were strong advocates for them in school performed better academically, socially and physically. These are called protective factors and they work to counter the effects of pre-term birth.
“These findings are important for parents, nurses in the neo-natal intensive care units, teachers and staff in the schools, disability services offices in colleges and primary care providers,” Sullivan said. “By identifying the issues pre-term babies face in childhood, adolescence and through adulthood, we can all be better prepared to take steps to mitigate their effects.”
Adoptive parents need to take all of this research into consideration when planning for their child. Mental health disorders are often diagnosed in the same timeframe as this latest research is indicating learning disabilities being revealed. Teasing out the differences between and cumulative effects of learning disabilities and mental health conditions and determining the best interventions are some of the most difficult tasks associated with adoptive parenting.
REFORM Puzzle Piece
Update: Another study is Paula L. Ruttle, Elizabeth A. Shirtcliff, Lisa A. Serbin, Dahlia Ben-Dat Fisher, Dale M. Stack, Alex E. Schwartzman. Disentangling psychobiological mechanisms underlying internalizing and externalizing behaviors in youth: Longitudinal and concurrent associations with cortisol. Hormones and Behavior, 2011; 59 (1): 123 DOI: 10.1016/j.yhbeh.2010.10.015
Science Daily 2/10/11 says “Researchers at Concordia University and the Centre for Research in Human Development may have resolved the cortisol paradox. In a groundbreaking study published in the journal Hormones and Behavior, they link cortisol levels not simply to behavior problems, but to the length of time individuals have experienced behavior problems.
“We studied the relationship between cortisol levels in young people with problematic behaviour such as aggression or depression, and the length of time since the onset of these behaviours,” explains Paula Ruttle, lead author and PhD candidate at Concordia’s Department of Psychology. “Cortisol levels were abnormally high around the time problem behaviours began, but abnormally low when they had been present for a long time.”
To obtain subjects’ cortisol levels, researchers analyzed saliva samples taken from 96 young people during early adolescence. They then matched cortisol levels to behavioral assessments taken in childhood and again during adolescence. Problem behaviours were classified as either “internalizing” (depression and anxiety) or “externalizing” (aggression, attentional problems).
Riding the cortisol roller coaster
Youngsters who developed depression-like symptoms or anxiety problems in adolescence had high levels of cortisol. However, those who developed symptoms earlier had abnormally low cortisol levels. The conclusion? Cortisol levels go up when individuals are first stressed by depression or anxiety, but then decline again if they experience stress for an extended period.
“It seems the body adapts to long-term stress, such as depression, by blunting its normal response,” says coauthor Lisa Serbin, a psychology professor who is Ruttle’s PhD supervisor and Concordia University Research Chair in Human Development.
“To take an extreme example, if someone sees a bear in the yard, that person experiences a ‘flight or fight’ reaction,” continues Serbin, a member of the Centre for Research in Human Development. “Stress levels and therefore cortisol levels go up. However, if the same person sees bears in the yard every day for a year, the stress response is blunted. Eventually, cortisol levels become abnormally low.”
Aggressive behavior in early childhood
At first glance, study results from children with aggressive behavior and attentional problems seem to contradict this theory. In this group they found that low levels of cortisol were related to aggressive behavior both during childhood and adolescence. However, the authors contend that since aggressive behavior often begins in the second year of life or earlier, subjects may have been stressed for years before entering the study, resulting in abnormally low cortisol levels.
“This blunted response makes sense from a physiological point of view,” says Ruttle. “In the short term, high levels of cortisol help the body respond to stress. However, in the long term, excessive levels of cortisol are linked to a range of physical and mental health problems. So, to protect itself, the body shuts down the cortisol system — but research shows that’s not good either.”
What, me worry?
Individuals with a blunted response to stress may not respond to things that would — and should — make other people nervous. For example, children with long-term behaviour problems perform poorly in school. Because of their blunted stress response, these youngsters may not be worried about exams, so they don’t bother to prepare as much as their peers.
The study has many significant implications, according to Serbin. “This research suggests interventions should begin as soon as a behavioural problem appears,” she says. “For children with severe externalizing problems, this may be very early, perhaps even when they are preschoolers or toddlers.
“We now have evidence that behavioural problems in children are linked to mental and physical health. Taking a ‘wait-and-see’ attitude may not be the right approach.”
This research was funded by the Social Sciences and Humanities Research Council of Canada and the Canadian Institutes of Health Research.”
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