Summary: Study examines the stability of an individual child’s depression and the effects of early life symptoms of depression on risks for developing depression later in life.
Ph.D. candidate Ida Sund Morken and her colleagues at NTNU’s Department of Psychology have investigated the extent to which depression in childhood increases the risk of developing new depression later, as well as looked at other forms of stability in depression.
The researchers used the database from the Trondheim Early Secure (TESS) study, where about one thousand children and their parents have follow-ups every other year, including clinical interviews.
“Depression is considered a persistent or recurring condition. But research provides few answers as to why children and adolescents stay depressed or have relapses over time,” says Morken.
The scar hypothesis
The scar hypothesis suggests that being depressed has consequences that contribute to the depression being maintained over time, or that make the person more susceptible to new depression. The consequences can be social withdrawal or changes in the brain.
“If the hypothesis is correct, we have reason for a certain optimism: If we manage to prevent or reduce early depression, the risk of the child developing depression later in childhood and adolescence decreases. The problem is that we don’t know if there’s support for the scar hypothesis,” says Morken.
Some underlying cause could perhaps be making children vulnerable instead, such as persistent factors that increase the risk of depression recurring repeatedly. Possible causes could be neglect on the part of the parents, everything from gross abuse to emotional absence, or vulnerability that lies in our genes.
The ‘stability’ of depression
The duration of depression up through children’s growing up has several aspects. According to Morken, the research literature provides knowledge about how stability is expressed, and the prevalence of depression at different ages at the group level. Research has also been done on how individuals with depression are doing—their “position” in depression as compared to their peers.
“In preventing and treating depression, it’s just as important to know how the individual child’s depression is doing—compared to him- or herself. What is the risk of the child remaining as depressed as he or she is now?
4–14 year olds
Morken’s study builds on existing stability research in how depression manifests itself, stability at the group level (prevalence) and stability in comparison with peers.
“We’re the first researchers to examine the stability of the individual’s depression and the effect of early depression on later depression. Using statistical analysis methods, we examined these types of stability in the 4–14 year old age range.
Greater stability than expected
“We found that depression is most common in adolescents, but that it can occur as early as preschool age. The study suggests that children’s level of depression is relatively stable compared to their peers. The children who scored highest on depression continued to fare the worst even at a later age,” Morken says.
The researchers found that stability is even stronger when individual children are compared with their own level of depression over time.
“Children who score high at an early stage thus continue to have a high level of depression—regardless of their peers,” she says.
Grounds for hope
“Our most important finding, however, is that a change in depression also turns out to be valid at a later date. Early worsening of depressive symptoms makes it more likely that the difficulties will recur. This is in line with the scar hypothesis, that depression in itself can lead to persistent and recurring depression. The symptoms of depression, even in preschool and early school age, seem to increase the susceptibility to, or have an effect on, later depression.
Fortunately, improving depression at one stage also contributes to improvement in the long run.
“The good news is that treatment and preventive measures that lead to improvement, can quite likely counteract persistent symptoms and relapses,” says Morken.
The researcher believes the finding gives solid grounds for optimism.
“I think this is good news and a strong argument for spending resources on early prevention and treatment, not only in the vulnerable adolescent period but also as young as kindergarten and primary school age,” says Morken.
The study does not address what types of preventive measures or forms of treatment should be used. Previous research has shown that various established treatment methods can yield good results, depending on the context and the individual child.
Depression from preschool to adolescence – five faces of stability
The term ‘stability’ has different meanings, and its implications for the etiology, prevention, and treatment of depression vary accordingly. Here, we identify five types of stability in childhood depression, many undetermined due to a lack of research or inconsistent findings.
Children and parents (n = 1,042) drawn from two birth cohorts in Trondheim, Norway, were followed biennially from ages 4–14 years. Symptoms of major depressive disorder (MDD) and dysthymia were assessed with the Preschool Age Psychiatric Assessment (only parents) and the Child and Adolescent Psychiatric Assessment (age 8 onwards).
(a) Stability of form: Most symptoms increased in frequency. The symptoms’ importance (according to factor loadings) was stable across childhood but increased from ages 12–14, indicating that MDD became more coherent. (b) Stability at the group level: The number of symptoms of dysthymia increased slightly until age 12, and the number of symptoms of MDD and dysthymia increased sharply between ages 12–14. (c) Stability relative to the group (i.e., ‘rank-order’) was modest to moderate and increased from ages 12–14. (d) Stability relative to oneself (i.e., intraclass correlations) was stronger than stability relative to the group and increased from age 12–14. (e) Stability of within-person changes: At all ages, decreases or increases in the number of symptoms forecasted similar changes two years later, but more strongly so between ages 12–14.
Across childhood, while most symptoms of MDD and dysthymia become more frequent, they are equally important. The transition to adolescence is a particularly vulnerable period: The depression construct becomes more coherent, stability increases, the level of depression increases, and such an increase predicts further escalation. Even so, intervention at any time during childhood may have lasting effects on reducing child and adolescent depression.
About this depression research news
Original Research: Closed access.
“Depression from preschool to adolescence – five faces of stability” by Ida Sund Morken et al. Journal of Child Psychology and Psychiatry