It’s well known that teenagers’ moods go through drastic changes. In particular, depressive symptoms – like feelings of low mood or self-loathing – tend to increase as they grow older. Now researchers have plotted out the exact trajectory of these depressive symptoms. In their recent paper in Journal of Youth and Adolescence, Alex Kwong and colleagues from the University of Bristol report for the first time the points during teen development when symptoms increase most rapidly, on average – and they find that these timings differ between young men and women.
The timing of symptom increases is of more than theoretical interest. Having more serious depression symptoms in adolescence is a known risk factor for developing depression later on in life, suggesting it could be useful to intervene and treat symptoms when they are at their worst. But when is that exactly? Past research has shown that, on average, depressive symptoms peak at some point in mid-to-late adolescence before decreasing again, but findings have been inconsistent: Scientists have suggested that peak depressive symptoms could occur as early as age 15 or as late as 20. And few studies have pinpointed other potentially important periods, such as the point at which depressive symptoms are increasing most rapidly, rather than simply when they have reached a peak.
To better characterise these critical points, Kwong’s team examined data from the Avon Longitudinal Study of Parents and Children. This study has been following children from birth in the 1990s through to today, providing an overview of development from childhood all the way through to adulthood.
The team looked at participants’ scores on the short mood and feelings questionnaire from the ages of 10 to 22. This questionnaire measures depressive symptoms over the previous two weeks, asking participants to indicate whether statements like “I felt miserable or unhappy” are true for them. Over the 12 year time period, participants had been given the questionnaire on eight separate occasions (although not everyone had completed every questionnaire: 7,335 participants completed the first questionnaire, decreasing to 3,850 by the final one).
The researchers fit a model to this data, showing the path of depressive symptoms for each individual through adolescence and early adulthood. They then averaged these curves across males and females, to give the general trajectory for each sex.
The team found that there were key differences between male and female participants. Females had higher depressive symptoms in general throughout their adolescence, except for between ages 10 and 11, when symptoms were higher for males. The symptoms didn’t peak until around age 20 for both sexes, but there were sex differences in the age at which symptoms increased most rapidly: for females this occurred at 13.7 years old, while for males it was much later, at 16.4 years old.
The researchers say that these sex differences in the trajectories could relate partly to puberty. Girls generally go through puberty earlier, which could explain why their depressive symptoms increase most rapidly almost 3 years earlier than boys’ symptoms. This also suggests that girls could benefit earlier than boys from interventions designed to prevent the increase of depressive symptoms.
However, this study is the first to estimate the age at which depressive symptoms increase most rapidly, so the findings should be considered preliminary. It’s also not yet clear whether it’s possible to slow or reverse these rapid increases in teen depression symptoms – or what the later effects of doing so would be. Nevertheless, the authors say, “if this can be used for clinical purposes, it may be possible to treat individuals at this age, which may help reduce depressive symptoms or depression at a later stage.”
—Identifying Critical Points of Trajectories of Depressive Symptoms from Childhood to Young Adulthood
Matthew Warren (@MattbWarren) is Staff Writer at BPS Research Digest
Reacher-Said-Nothing on March 16th, 2019 at 16:44 UTC »
The title is unclear. Ages 13.7 and 16.4 are the ages when the depressive symptoms increase at the highest rate, IE accelerate the fastest. Not when the depressive symptoms are at their most numerous or severe.
The actual symptoms themselves peaked at around 20. Unfortunately while the title is technically correct, I think most people in the comments are assuming the title means "13.7 and 16.4 are the toughest ages for female and male teenagers". I'm not sure why they chose the rate of acceleration as the headlining figure, perhaps to indicate when parents should start noticing changes.
yeahokbye on March 16th, 2019 at 14:36 UTC »
Iirc, this is largely due to hormonal changes. Females tend to go through puberty at an earlier age than males and that age difference correlates very closely with the age difference here. I’ve also read that females hit another peak of depressive symptoms around the age of 50, again attributed to a large hormonal shift as well as other significant life changes.
mvea on March 16th, 2019 at 10:40 UTC »
The title of the post is a copy and paste from the first and sixth paragraphs of the linked academic press release here:
Journal Reference:
Identifying Critical Points of Trajectories of Depressive Symptoms from Childhood to Young Adulthood
Kwong, A.S.F., Manley, D., Timpson, N.J. et al.
Journal of Youth and Adolescence 2019
Doi: https://doi.org/10.1007/s10964-018-0976-5
Link: https://link.springer.com/article/10.1007/s10964-018-0976-5
Abstract
Depression is a common mental illness and research has focused on late childhood and adolescence in an attempt to prevent or reduce later psychopathology and/or social impairments. It is important to establish and study population-averaged trajectories of depressive symptoms across adolescence as this could characterise specific changes in populations and help identify critical points to intervene with treatment. Multilevel growth-curve models were used to explore adolescent trajectories of depressive symptoms in 9301 individuals (57% female) from the Avon Longitudinal Study of Parents and Children, a UK based pregnancy cohort. Trajectories of depressive symptoms were constructed for males and females using the short mood and feelings questionnaire over 8 occasions, between 10 and 22 years old. Critical points of development such as age of peak velocity for depressive symptoms (the age at which depressive symptoms increase most rapidly) and the age of maximum depressive symptoms were also derived. The results suggested that from similar initial levels of depressive symptoms at age 11, females on average experienced steeper increases in depressive symptoms than males over their teenage and adolescent years until around the age of 20 when levels of depressive symptoms plateaued and started to decrease for both sexes. Females on average also had an earlier age of peak velocity of depressive symptoms that occurred at 13.5 years, compared to males who on average had an age of peak velocity at 16 years old. Evidence was less clear for a difference between the ages of maximum depressive symptoms which were on average 19.6 years for females and 20.4 for males. Identifying critical periods for different population subgroups may provide useful knowledge for treating and preventing depression and could be tailored to be time specific for certain groups. Possible explanations and recommendations are discussed.