summary: Social support during stressful times helps reduce the risk of developing symptoms in people who have a genetic predisposition to depression.
Source: University of Michigan
It’s always a good idea to reach out to someone’s support when they’re under stress. But a new study suggests that support can be especially important for someone whose genetic makeup makes them more likely to develop depression.
The study shows the importance of social support in reducing the risk of developing depressive symptoms in general, using data from two very different groups of people under stress: new doctors in their most intense years of training, and older adults whose spouses recently died.
But the biggest effect was seen in those with the greatest amount of genetic variation that increased the risk of depression.
The paper uses a measure of genetic risk called the Polygenic Risk Score, which is based on decades of research on small differences in specific genes associated with depression risk.
Compared to individuals in the study with low polygenic depression risk scores, the physicians and widows with higher risk scores had higher rates of depression after they lost social support, but also lower rates of depression when they obtained social support during stressful times.
The study published in American Journal of Psychiatry By a team from the University of Michigan, it suggests more could be done to target social support to those who could benefit the most.
Genes, stress and social connection
“Our data shows great variability in the level of social support individuals receive during these difficult times, and how it has changed over time,” said first author Jennifer Cleary, MS, a PhD student in psychology at UM who is conducting her research with senior author Srijan. Sen, MD, PhD, from UM College of Medicine.
“We hope that these findings, which include genetic risk scores as well as measures of social support and depressive symptoms, will shed light on gene-environment interactions and specifically the importance of social contact in depression risk.”
Sen, who is director of the Eisenberg Center for Family Depression and professor of psychiatry and neuroscience, adds that even as genetic research is revealing more DNA variation associated with depression vulnerability, learning how this variation leads to depression is critical.
“Understanding the different genetic profiles associated with sensitivity to loss of social support, inadequate sleep, excessive work stress and other risk factors can help us develop personalized guidelines for depression prevention,” he said.
“Meanwhile, these findings reaffirm the importance of social connections, social support, and an individual’s sensitivity to the social environment as factors in well-being and the prevention of depression.”
Different populations have similar patterns
The new study used data from two long-term studies that both capture genetic, temperament, environment and other data from groups of participating individuals.
One is the Internal Health Study, which enrolls first-year medical residents (also called interns) throughout the United States and abroad, which Sen directs.
The other is the Health and Retirement Study, based at the UM Institute for Social Research.
The data for the new paper came from 1,011 interns trained in hospitals across the country, about half of whom were female, and from 435 recently widowed people, 71% of whom were women, who had data available from surveys conducted before and after their spouse’s death. .
In the trainees, as Sen and his team showed in previous work, depressive symptoms increased significantly (126%) during the year of stressful training involving long and irregular working hours—often in environments far from friends and family.
In widows and widowers, depressive symptoms were 34% higher than pre-widow scores. Cleary said this ties in with previous research showing that losing a spouse can be one of the biggest stressors in a person’s life.
Next, the researchers combined the scores for depression symptoms with each person’s polygenic risk score for depression, and their individual responses to questions about relationships with friends, family, and other social supporters.
Most trainees have lost the social support from their pre-training days – which fits well with the common experience of leaving where they attended medical school and going into a new environment where they may not know anyone.
Trainees with the highest polygenic risk scores who also lost social support had the highest scores on measures of depressive symptoms later in the stressful trainee year.
Those with the same high level of genetic risk who had access to social support had significantly fewer depressive symptoms. In fact, it was lower than their low genetic risk peers, no matter what happened to their social support. Researchers call this the “cross effect.”
In contrast to interns, some widows reported an increase in social support after the loss of their husbands, perhaps because friends and family reached out to offer help or just a listening ear.
But the influence of the crossover was also evident in them. Widows at high genetic risk for depression who had access to social support showed a significantly lower increase in depressive symptoms than their peers at similar genetic risk who lost social support after the loss of a spouse.
There were also some widows who lost social support or experienced no change in support, and whose depressive symptoms did not change. Cleary notes that in future work, it will be important to look at the history of this group in light of any care they may have given to a spouse suffering from a long-term illness.
The team also hopes that other researchers will study this same interaction between genetic risk, stress and social support in other populations.
In the meantime, Cleary and Senn say, the message for anyone going through difficult times, or who has watched a friend or relative go through difficult times, is to reach out and maintain or strengthen social connections.
They noted that doing so can have benefits for both the person under stress and the person communicating with them.
Reducing the level of ongoing stress a person experiences, whether it be at work, school, after a personal loss, or in family situations, can be critical.
And although the study did not examine the role of professional help in mental health, individual and group therapy is an important option for those who have developed depression or other mental health issues.
About this news genetics and depression
Original search: Closed access.
“Polygenic risk and social support in predicting depression under stressWritten by Jennifer L Cleary, et al. American Journal of Psychiatry
Polygenic risk and social support in predicting depression under stress
Despite significant progress in identifying genetic variation associated with major depression, the mechanisms by which genomic and environmental factors jointly influence depression risk remain unclear. Genomically conferred sensitivity to the social environment may be one mechanism linking genetic variation and depressive symptoms. The authors assessed whether social support affects the susceptibility to depression differently across the genomic risk spectrum in two samples that had experienced significant life stress: 1011 first-year (intern) IHS health study interns and 435 recently widowed health subjects. and participants in the Retirement Study (HRS).
Depressive symptoms and participants’ social support were assessed through questionnaires completed before and after life stressors. Polygenic risk scores (PRS) for major depressive disorder were calculated for both samples.
Scores for depressive symptoms increased by 126% after initiation of training in the IHS sample and by 34% after widowhood in the HRS sample. There was an interaction between depression PRS and change in social support in predicting depressive symptoms in both IHS samples (incidence rate ratio [IRR]= 0.96, 95% CI = 0.93, 0.98) and HRS sample (IRR = 0.78, 95% CI = 0.66, 0.92), with higher depression PRS associated with greater sensitivity to changes in social support. The Johnson-Nieman periods indicated a cross-over effect, in which losses and gains in social support moderated the effect of PRS on depressive symptoms. (Johnson-Nieman interval in the IHS sample, 0.02, 0.71; in the HRS sample, −0.49, 1.92).
The results of the study indicate that individuals with a high genetic risk for developing increased depressive symptoms under adverse social conditions also benefit most from nurturing social environments.