Stress in childhood and adulthood have combined impact on hormones and health
April 3, 2019
Science Daily/Association for Psychological Science
Adults who report high levels of stress and who also had stressful childhoods are most likely to show hormone patterns associated with negative health outcomes, according to findings published in Psychological Science, a journal of the Association for Psychological Science.
One of the ways that our brain responds to daily stressors is by releasing a hormone called cortisol -- typically, our cortisol levels peak in the morning and gradually decline throughout the day. But sometimes this system can become dysregulated, resulting in a flatter cortisol pattern that is associated with negative health outcomes.
"What we find is that the amount of a person's exposure to early life stress plays an important role in the development of unhealthy patterns of cortisol release. However, this is only true if individuals also are experiencing higher levels of current stress, indicating that the combination of higher early life stress and higher current life stress leads to the most unhealthy cortisol profiles," says psychological scientist Ethan Young, a researcher at the University of Minnesota.
For the study, Young and colleagues examined data from 90 individuals who were part of a high-risk birth cohort participating in the Minnesota Longitudinal Study of Risk and Adaptation.
The researchers specifically wanted to understand how stressful events affect the brain's stress-response system later in life. Is it the total amount of stress experienced across the lifespan that matters? Or does exposure to stress during sensitive periods of development, specifically in early childhood, have the biggest impact?
Young and colleagues wanted to investigate a third possibility: Early childhood stress makes our stress-response system more sensitive to stressors that emerge later in life.
The researchers assessed data from the Life Events Schedule (LES), which surveys individuals' stressful life events, including financial trouble, relationship problems, and physical danger and mortality. Trained coders rate the level of disruption of each event on a scale from 0 to 3 to create an overall score for that measurement period. The participants' mothers completed the interview when the participants were 12, 18, 30, 42, 48, 54, and 64 months old; when they were in Grades 1, 2, 3, and 6; and when they were 16 and 17 years old. The participants completed the LES themselves when they were 23, 26, 28, 32, 34, and 37 years old.
The researchers grouped participants' LES scores into specific periods: early childhood (1-5 years), middle childhood (Grades 1-6), adolescence (16 and 17 years), early adulthood (23-34 years), and current (37 years).
At age 37, the participants also provided daily cortisol data over a 2-day period. They collected a saliva sample immediately when they woke up and again 30 minutes and 1 hour later; they also took samples in the afternoon and before going to bed. They sent the saliva samples to a lab for cortisol-level testing.
The researchers found that neither total life stress nor early childhood stress predicted cortisol level patterns at age 37. Rather, cortisol patterns depended on both early childhood stress and stress at age 37. Participants who experienced relatively low levels of stress in early childhood showed relatively similar cortisol patterns regardless of their stress level in adulthood. On the other hand, participants who had been exposed to relatively high levels of early childhood stress showed flatter daily cortisol patterns, but only if they also reported high levels of stress as adults.
The researchers also investigated whether life stress in middle childhood, adolescence, and early adulthood were associated with adult cortisol patterns, and found no meaningful relationships.
These findings suggest that early childhood may be a particularly sensitive time in which stressful life events -- such as those related to trauma or poverty -- can calibrate the brain's stress-response system, with health consequences that last into adulthood.
Young and colleagues note that cortisol is one part of the human stress-response system, and they hope to investigate how other components, such as the microbiome in our gut, also play a role in long-term health outcomes.
https://www.sciencedaily.com/releases/2019/04/190403080454.htm
Is anxiety in childhood and adolescence linked to later alcohol use disorders?
March 20, 2019
Science Daily/Wiley
In an Addiction analysis of relevant published studies, investigators found some evidence for a positive association between anxiety during childhood and adolescence with later alcohol use disorders.
Approximately 43 percent of associations were positive, meaning that anxiety was associated with a higher likelihood of later alcohol use disorders; however, 11 percent of associations were negative, with anxiety being associated with a lower likelihood of later alcohol use disorders. Approximately 30 percent of associations were equivocal and 15 percent were unclassifiable based on the information reported.
The authors of the analysis noted that it is important to establish which anxious individuals consume more alcohol and develop alcohol use disorders in order to develop targeted interventions.
"The evidence from prospective cohort studies is suggestive but not conclusive of a positive association between anxiety during childhood and adolescence and subsequent alcohol use disorder," said lead author Maddy Dyer, of the University of Bristol, in the UK. "Associations of anxiety with later drinking frequency or quantity and binge drinking were inconsistent. Further research is needed to understand why there are differences in associations for consumption levels versus problematic use, and to determine which individuals with anxiety develop alcohol problems."
https://www.sciencedaily.com/releases/2019/03/190320102030.htm
Brain matures faster due to childhood stress
June 15, 2018
Science Daily/Radboud University Nijmegen
Stress in early childhood leads to faster maturation of certain brain regions during adolescence. In contrast, stress experienced later in life leads to slower maturation of the adolescent brain.
In 1998, the group -- which then comprised 129 one-year-olds and their parents -- was tested for the first time. Over the past 20 years, researchers studied, inter alia, their play sessions and interactions with parents, friends and classmates. The children were also subjected to MRI scans. This wealth of data has enabled Karin Roelofs, Professor of Experimental Psychopathology, her PhD student Anna Tyborowska and other colleagues of Radboud University to investigate how stress in various life stages affected the adolescent brain of these children.
More specifically, they looked at the effects on cerebral maturation. During adolescence, our brain experiences a natural pruning process in which previously made connections between brain cells are refined, allowing the creation of more useful and efficient networks.
More pruning due to early life stress
The researchers investigated two types of stressors -- negative life events and negative influences from the social environment -- in two life stages of their subjects: early childhood (0-5 years) and adolescence (14-17 years). They related these stress levels to the maturation of the prefrontal cortex, amygdala and hippocampus. These brain regions play an important role in functioning in social and emotional situations and are known to be sensitive to stress.
Stress due to negative experiences during childhood , such as illness or divorce, appears to be related to faster maturation of the prefrontal cortex and amygdala in adolescence. However, stress resulting from a negative social environment during adolescence, such as low peer esteem at school, is connected to slower maturation of the brain area hippocampus and another part of the prefrontal cortex. 'Unfortunately, in this study we can't say with certainty that stress causes these effects. However, based on animal studies we can hypothesize that these mechanisms are indeed causal,' Anna Tyborowska says.
Loss of flexibility
'The fact that early childhood stress accelerates the maturation process during adolescence is consistent with theories of evolutionary biology,' says Tyborowska. 'From an evolutionary perspective, it is useful to mature faster if you grow up in a stressful environment. However, it also prevents the brain from adjusting to the current environment in a flexible way. In other words, the brain become "mature" too soon.' The researchers were surprised to find, however, that social stress later in life seems to lead to slower maturation during adolescence. Tyborowska: 'What makes this interesting is that a stronger effect of stress on the brain also increases the risk of developing antisocial personality traits'.
Tyborowska is now conducting the eleventh round of measurements, with the subjects now being in their twenties. 'Now that we know that stress affects the maturation of brain regions that also play a role in the control of emotions, we can investigate how this development continues later in life'.
Longitudinal study from Nijmegen
The Nijmeegse Longitudinale Studie (Nijmegen Longitudinal Study) was initiated in 1998. This study aims to investigate how the development and functioning of children at various ages is influenced by their interactions with parents and peers and how this relates to their disposition and personality. Several research groups have access to the data collected from the subjects (at present about 100). Other research topics include mother-child relationships, bullying and risk behaviour. This long-term study is one of the few worldwide in which so many measurements are taken over such a long period.
https://www.sciencedaily.com/releases/2018/06/180615094830.htm
Childhood stress fuels weight gain in women
July 7, 2015
Science Daily/Michigan State University
When it comes to weight gain for women, childhood stress appears to be a bigger culprit than stress during adulthood, finds an American national study. Interestingly, though, neither childhood nor adult stress was associated with weight gain for men.
Interestingly, though, neither childhood nor adult stress was associated with weight gain for men.
The federally funded study, which appears online in the journal Social Science & Medicine, is the first to examine such lifelong consequences of stress on weight change.
"These findings add to our understanding of how childhood stress is a more important driver of long-term weight gain than adult stress, and how such processes differ for men and women," said Hui Liu, MSU associate professor of sociology and an expert in statistics, population-based health and family science.
Liu and her longtime collaborator, Debra Umberson from the University of Texas, analyzed the data from the Americans' Changing Lives, a national survey in which participants were interviewed four times in a 15-year period. The study encompassed 3,617 people (2,259 women and 1,358 men).
Childhood stress was measured on a range of family-related stressors that occurred at age 16 or younger such as economic hardship, divorce, at least one parent with mental health problem and never knowing one's father. Adult stress included such factors as job loss, death of a significant other and parental and care-provider stress.
Liu said women who experienced higher levels of childhood stress gained weight more rapidly than women who experienced less childhood stress. Change in body mass is a process that unfolds throughout life, she noted, and childhood may be a critical period for establishing patterns that have a long-term impact on women's weight over time.
As far as stress not significantly affecting men's weight, Liu said men and women respond to stress differently.
It may be that women eat more to cope with stress, whereas men are more likely to engage in less weight-related strategies such as withdrawing or drinking alcohol, she said. Gender differences in depression may also help explain the difference. Depression is associated with emotion-driven eating and weight gain, and females are more likely than males to be depressed after adolescence.
The findings highlight the need for treatment and policies designed to reduce stress in childhood.
"Given the importance of body mass on health and disability," Liu said, "it's important that we consider the sex-specific social contexts of early childhood in order to design effective clinical programs that prevent or treat obesity later in life."
http://www.sciencedaily.com/releases/2015/07/150707120214.htm
Stress May Delay Brain Development in Early Years
June 6, 2012
Science Daily/University of Wisconsin-Madison
Stress may affect brain development in children, altering growth of a specific piece of the brain and abilities associated with it, according to researchers at the University of Wisconsin-Madison.
"There has been a lot of work in animals linking both acute and chronic stress to changes in a part of the brain called the prefrontal cortex, which is involved in complex cognitive abilities like holding on to important information for quick recall and use," says Jamie Hanson, a UW-Madison psychology graduate student. "We have now found similar associations in humans, and found that more exposure to stress is related to more issues with certain kinds of cognitive processes."
Children who had experienced more intense and lasting stressful events in their lives posted lower scores on tests of what the researchers refer to as spatial working memory. They had more trouble navigating tests of short-term memory such as finding a token in a series of boxes, according to the study, which will be published in the June 6 issue of the Journal of Neuroscience.
Brain scans revealed that the anterior cingulate, a portion of the prefrontal cortex believed to play key roles in spatial working memory, takes up less space in children with greater exposure to very stressful situations.
"We're not trying to argue that stress permanently scars your brain. We don't know if and how it is that stress affects the brain," Hanson says. "We only have a snapshot -- one MRI scan of each subject -- and at this point we don't understand whether this is just a delay in development or a lasting difference. It could be that, because the brains is very plastic, very able to change, that children who have experienced a great deal of stress catch up in these areas."
The researchers determined stress levels through interviews with children ages 9 to 14 and their parents. The research team, which included UW-Madison psychology professors Richard Davidson and Seth Pollak and their labs, collected expansive biographies of stressful events from slight to severe.
"Instead of focusing in on one specific type of stress, we tried to look at a range of stressors," Hanson says. "We wanted to know as much as we could, and then use all this information to later to get an idea of how challenging and chronic and intense each experience was for the child."
Interestingly, there was little correlation between cumulative life stress and age. That is, children who had several more years of life in which to experience stressful episodes were no more likely than their younger peers to have accumulated a length stress resume. Puberty, on the other hand, typically went hand-in-hand with heavier doses of stress.
The researchers, whose work was funded by the National Institutes of Health, also took note of changes in brain tissue known as white matter and gray matter. In the important brain areas that varied in volume with stress, the white and gray matter volumes were lower in tandem.
White matter, Hanson explained, is like the long-distance wiring of the brain. It connects separated parts of the brain so that they can share information. Gray matter "does the math," Hanson says. "It takes care of the processing, using the information that gets shared along the white matter connections."
Gray matter early in development appears to enable flexibility; children can play and excel at many different activities. But as kids age and specialize, gray matter thins. It begins to be "pruned" after puberty, while the amount of white matter grows into adulthood.
"For both gray and white matter, we actually see smaller volumes associated with high stress," Hanson says. "Those kinds of effects across different kinds of tissue, those are the things we would like to study over longer periods of time. Understanding how these areas change can give you a better picture of whether this is just a delay in development or more lasting."
http://www.sciencedaily.com/releases/2012/06/120606164936.htm
Early childhood stress affects brain's response to rewards
Study finds lingering changes in brain activity
October 19, 2015
Science Daily/Duke University
A new study has pinpointed how early childhood stress affects brain activity, related to risks for depression and other mental health problems in adulthood.
A Duke University-led study has pinpointed how early childhood stress affects the adult brain's response to rewards. Their findings suggest a possible pathway by which childhood stress may increase risk of depression and other mental health problems in adulthood.
Many studies have connected early life stress to later mental health issues for adults, but little is understood about the reasons for this connection. The new study published in the current issue of Social Cognitive and Affective Neuroscience used functional magnetic resonance imaging (fMRI) to examine the relations between early life stress and reward-related brain activity in adults.
Participants in the study were closely monitored beginning in kindergarten and then were scanned using brain imaging when they were adults. The participants were all part of the Fast Track Project, which in 1991 began tracking how children developed across their lives.
For this new study, researchers focused on the levels of stress that 72 subjects were exposed to early in development. At age 26, the study participants completed an experimental game to assess how their brains processed rewards and positive feedback. The scientists focused on reward-related activity in an area of the brain known as the ventral striatum, measured using fMRI.
"We found that greater levels of cumulative stress during childhood and adolescence predicted lower reward-related ventral striatum activity in adulthood," said study lead author Jamie Hanson, a postdoctoral researcher at Duke's Center for Child and Family Policy and the Duke Department of Psychology and Neuroscience.
Hanson and colleagues found that early stress, specifically between kindergarten and grade three, was most strongly associated with muted responses to rewards in adulthood. Previous studies have identified this type of brain activity as a marker for increased risk of depression and anxiety.
"In participants with the greatest levels of early stress, we saw the lowest levels of activity in the ventral striatum in response to a reward," Hanson said.
"We think reward-related ventral striatum activity is an important marker of mental health," Hanson explained. "Past studies have focused on the processing of threat and negative emotion after early stress. Generating positive emotions may potentially buffer some of the effects of stress."
The researchers say that a variety of early life stresses may affect whether children or not will grow up to be at risk for mental health problems. They add that further work in this area may lead to the development of new interventions that will help prevent negative mental health outcomes after childhood stress.
http://www.sciencedaily.com/releases/2015/10/151019110955.htm