Depression and Guilt: What Is the Link?
A study out of Washington University in St. Louis points to something measurable in the brains of very young children with depression. Kids between three and six who met the criteria for major depressive disorder had a smaller anterior insula than their peers who were not depressed. The anterior insula sits deep in the brain and has been tied to how we process emotion, including guilt, along with perception, self-awareness, and thinking. What the researchers saw in these children lines up with what adult studies have already reported: the function and structure of the insula shift in people living with MDD.
The work grew out of the Preschool Depression Study, which started with a fairly basic question. Could a child as young as three actually be clinically depressed? Over ten years, researchers followed 306 children who were between three and six when they joined. Each year for six years, the kids were assessed for depression and for guilt. A smaller group inside the study went further and had MRI scans roughly every 18 months, from age six up through 13.
Among the participants, 47 were diagnosed with depression during their preschool years. Another 82 showed no depressive symptoms at all. The guilt numbers stood out. Of the depressed children, 55 percent showed signs of pathological guilt. In the non-depressed group, about 20 percent displayed what the researchers called excessive guilt. That kind of heavy, out-of-proportion guilt is not unique to depression. It also turns up in anxiety, bipolar disorder, and OCD.
Children who carried both depression and pathological guilt tended to have a smaller right anterior insula. Follow the group over time and another pattern appears: the kids with smaller insula volumes were the ones more likely to cycle back into depressive episodes as they aged.
Andrew Belden, assistant professor of child psychiatry at the Washington University School of Medicine, led the team, and he says the direction of the findings tracks with decades of earlier observation. Excessive guilt, he notes, has long predicted depression and often shows up as a consequence of being depressed. His reading of the data goes a step further. Guilt early in a child's life seems to predict shrinkage of the insula. As he put it, depression may drive changes in the brain, and those changes in turn raise the odds of the illness coming back.
None of this means every child in the study is headed for a lifetime of depressive episodes. Some will never have a second one. Others will live with chronic depression, and being able to spot a warning sign in a three-year-old rather than waiting until adolescence or adulthood is worth a great deal.
Separate research backs the concern about recurrence. Elementary and middle school children who had been depressed in preschool were about 2.5 times more likely to be clinically depressed later than classmates with no history of it. And in adults, the same structural difference holds: those diagnosed with depression tend to have a smaller insula than those without symptoms. The link between reduced insula volume and depression keeps showing up regardless of how old the patient is.
Joan Luby, MD, professor of psychiatry and director of the Early Emotional Development Program at Washington University, worked on the study as a co-investigator. She told Medscape Medical News that children with a very early onset form of depression show brain changes closely matching what is already known in adults. Their study, she noted, is the first to look at the anterior insula as a possible biomarker for diagnosing depression in childhood.
Luby makes a practical point for anyone working with young patients. Clinicians should stay open to the idea that small children really can be clinically depressed, and pathological guilt is a symptom worth identifying and taking seriously. Early symptoms come with real, physical brain change, which is reason enough not to wave them off. If this is a disorder that both arrives early and keeps returning, she argues, there is a case for treating it early, when the available interventions tend to work better.
The findings were published online in JAMA Psychiatry on November 12, 2014, as the first study of its kind suggesting that reduced anterior insula volume could be a physiological marker for childhood MDD. The researchers planned to keep the study going for another five years, following their subjects through adolescence, which carries a high risk for depression. Their hope is that this kind of information helps flag who is most likely to relapse and reaches at-risk children early enough to do something about it.
The short version: a smaller insula shows up alongside major depressive disorder across the age range, and heavy guilt may play a part in how depression develops. Belden, Barch, Oakberg, April, Harms, Botterton, and Luby reported the insula and guilt findings in JAMA Psychiatry on November 12, 2014. Coverage of the preschool guilt and brain findings came from Deborah Brauser for Medscape on November 14, 2014, and from Washington University in St. Louis via ScienceDaily on the same November 12 date.