(CNN) The kids are not all right, a new analysis suggests.
During the Covid-19 pandemic, depression and anxiety in youth doubled compared to pre-pandemic levels, according to the research. One in 4 adolescents globally are "experiencing clinically elevated depression symptoms, while 1 in 5 youth are experiencing clinically elevated anxiety symptoms."
"Results from this analysis suggest that the pandemic has likely instigated a global mental health crisis in youth," said study author Sheri Madigan, an associate professor of clinical psychology and Canada research chair in determinants of child development at the University of Calgary.
As the months went by, these negative impacts on youth only got worse, the study found. This surprised Madigan, who said she thought "they would be more resilient and malleable to the challenges of the pandemic" as it persisted.
This cumulative toll could be due to the persistent social isolation, missed milestones, family financial problems and extended school disruptions, according to the analysis. Further studies following children for a longer period of time should be conducted, the study noted, to monitor the ongoing effects.
The meta-analysis, published Monday in JAMA Pediatrics, reviewed 29 studies with a total of more than 80,000 participants globally, ranging from age 4 to 17 with a mean age of 13. The included studies, which used empirical clinical data on depression and anxiety, were conducted in East Asia, Europe, North America, the Middle East, and Central and South America.
Youth mental health had already been declining prior to the pandemic. More than 1 in 3 high school students reported having persistent feelings of sadness or hopelessness in 2019, a 40% increase from 2009, according to the US Centers for Disease Control and Prevention.
The pandemic created conditions that might have exacerbated these negative feelings. With school closures and remote learning, children experienced the loss of peer interactions, greater social isolation, and less interaction with other supportive adults like teachers and coaches. These changes may have contributed to increased symptoms of depression, such as feelings of sadness, loss of interest in activities, and disruption to appetite and sleep, according to the study.
Additionally, the general uncertainty and disruptions of daily routines caused by the pandemic likely increased symptoms of generalized anxiety in youth, including fear, uncontrollable worry and hyperarousal, the study noted. Worry for the health of family and friends as Covid-19 spread also likely contributed to children's heightened anxiety, according to the research.
"Children and youth have experienced extraordinary disruption and stress during the pandemic, and it's taken a toll on their mental health," Madigan said. "When mental health problems persist and aren't properly addressed, they can have lasting consequences."
The study's findings are consistent with what Jenna Glover, a child clinical psychologist and director of psychology training at Children's Hospital Colorado, said she is seeing on the ground. She was not involved in the study.
"The disruption to their routines and consistency is very damaging for a child's mental health," Glover said. "They thrive on predictability, which has been absent for over a year."
The chronic stress and instability children are experiencing can lead to feelings of hopelessness, which is one of the top predictors of suicide ideation, she added.
In addition to the general increase in youth mental illness, the study also found that older children were impacted more severely than younger ones, possibly due to puberty and hormonal changes on top of the loss of social interaction.
Girls showed greater prevalence of depression and anxiety, too, which, according to the study, is in line with research prior to the pandemic. While this is a well-known phenomenon, it often gets glossed over in conversations about mental health, Glover said.
"This is not good for youth, but it is especially bad for females," she said. "Thinking about real targeted interventions and screenings based on knowing those things I think is an important takeaway from this study."
Researchers should continue to monitor the youth mental health situation as the pandemic continues and examine ways to address this crisis, Madigan said.
"This is a critical time. When we talk about children and youth being the future of our societies, this couldn't be more real or truthful," Madigan said. "If youth grow through this pandemic with increasing levels of stress and mental health challenges, society could be in for some real challenges as youth age into adulthood."
Keeping regular routines is integral to young people's well-being, emphasized Brae Anne McArthur, a postdoctoral research fellow at the University of Calgary and a clinical child psychologist who was also involved in the study.
"Knowing that children and youth thrive in the context of clear routines, it is important that children and youth remain in school and extracurricular activities," McArthur said.
That's why schools should be kept open as much as safely possible, Madigan said.
"Schools can be a refuge for many youths, but also, up to 80% of youth rely on school-based services and resources to address their mental health needs," she said. "If schools are closed, many youths who need help may feel they have nowhere to turn to get it, which could have drastic consequences."
Glover echoed that schools should be kept open to the extent possible. Parents also can take action by checking in with their kids and monitoring their sleeping and eating habits as well as their mood, she said.
McArthur said although the situation is dire, we still have time to turn it around.
"It (the study) does not suggest that we cannot recover from this mental health crisis," she said. "If we can come together as parents, researchers, clinicians and policy-makers to develop clear and actionable ways to move forward to support child and youth mental health, we can re-write this story in another year's time."