Persistent Insomnia Since Childhood Linked with Mood, Anxiety Disorders in Adults

Insomnia symptoms that persisted since childhood were strong determinants of mood and anxiety disorders in young adults, a 15-year longitudinal study showed.

Difficulty initiating or maintaining sleep that continued from childhood through adolescence and into young adulthood was tied to a three-fold increased risk of internalizing disorders (HR 3.19), reported Julio Fernandez-Mendoza, PhD, of Penn State College of Medicine in Hershey, Pennsylvania, at SLEEP 2021, a joint meeting of the American Academy of Sleep Medicine and the Sleep Research Society.

Incident insomnia symptoms that developed over the course of the study were associated with a two-fold increased risk of developing internalizing disorders in young adulthood (HR 1.94), Fernandez-Mendoza said.

A waxing-and-waning trajectory of insomnia symptoms also was linked with internalizing disorders in young adulthood (HR 1.53). No increased risk of internalizing disorders was seen in children whose insomnia symptoms remitted during the study period (HR 1.00).

“We found that about 40% of children do not outgrow their insomnia symptoms in the transition to adolescence and are at risk of developing mental health disorders later on during early adulthood,” Fernandez-Mendoza said.

Internalizing disorders, which include depressive and anxiety disorders, are the most common form of psychopathology and have a typical onset after age 18. Insomnia symptoms have been associated with these disorders in children, but how trajectories of insomnia affect children as they transition into adulthood is not well understood, Fernandez-Mendoza noted.

The study looked at data from the Penn State Child Cohort, a population-based sample of 700 children with a median age of 8.6. Of this group, 421 participants had followup data 7.5 years later when they were adolescents (median age 16.5), and 502 people had data 15 years later when they were young adults (median age 24).

Insomnia symptoms were defined as moderate-to-severe difficulties initiating or maintaining sleep. Symptoms were parent-reported in childhood and self-reported in adolescence and young adulthood. Developmental trajectories of insomnia symptoms across the three timepoints were classified as never, remitted, waxing-and-waning, persistent, or incident.

Diagnosis and treatment for mood or anxiety disorders were self- or parent-reported. About half of participants at each time point were female and 22% belonged to a racial or ethnic minority group. Results were adjusted for sex, race, ethnicity, age, and prior history of internalizing disorders or use of medications for mental health problems.

In childhood, 4.6% of participants had internalizing disorders. That climbed to 14.4% in adolescence and jumped to 43.3% in young adulthood. Childhood-onset insomnia symptoms that persisted across the three timepoints were strong determinants of internalizing disorders in young adulthood, independent of past diagnosis or medication use.

“These new findings further indicate that early sleep interventions are warranted to prevent future mental health problems, as children whose insomnia symptoms improved over time were not at increased risk of having a mood or anxiety disorder as young adults,” Fernandez-Mendoza said.

A limitation of the study was its reliance on self-reported data.