Disparities in sleep health and insomnia may begin at a young age

A team, led by Penn State researchers, found that children and teens from racial and ethnic minority groups are disproportionately affected by persistent insomnia symptoms that begin in childhood and continue through young adulthood. Specifically, Black children were 2.6 times more likely to experience these long-term sleep problems compared to white children. The findings underscore the need to identify insomnia symptoms early and intervene with age-appropriate treatment.

"Insomnia is a public health problem," said Julio Fernandez-Mendoza, professor at Penn State College of Medicine and senior author of the study recently published in the journal SLEEP. "We've identified that more people than we thought have childhood-onset insomnia where symptoms start in childhood and remain chronic all the way through young adulthood."

Poor sleep is linked to cardiometabolic disease, depression and anxiety, among other concerns. Yet, when it comes to sleep and children, insomnia symptoms aren't always taken seriously. Fernandez-Mendoza said that most people assume that difficulty falling asleep and staying asleep is a phase that kids will outgrow.

"Insomnia isn't like childhood sleep terrors or sleepwalking. It won't go away with puberty and maturation for many children," Fernandez-Mendoza said. Childhood-onset insomnia confers a greater risk for health problems because of the chronic exposure to sleeplessness, he explained. Those risks may be higher for Black and Hispanic/Latino children compared to non-Hispanic white children because disparities in sleep patterns begin at a young age.

The researchers followed 519 participants from the Penn State Child Cohort, a random, population-based study established in 2000. Participants were first recruited as school-age children, between the ages of 5 and 12, and were followed as adolescents and young adults, with assessments at the mean ages of 9, 16 and 24, respectively. Each time point represents a different maturational and development stage. At each stage, participants -- or their parents during childhood -- reported on difficulty falling or staying asleep and underwent an in-lab sleep study like the one used to diagnose sleep apnea or other sleep disorders. This longitudinal data was then used to determine what happens to sleep during this specific lifespan period. The researchers wanted to know: Does insomnia that starts in childhood resolve with age or does it persist?

The study is one of the first to look at how childhood insomnia symptoms evolve over the long-term and investigate how the trajectory of insomnia differs between racial and ethnic groups, addressing a gap in the research literature, Fernandez-Mendoza said. The researchers found that 23.3% of participants had persistent insomnia symptoms, with symptoms present at all three time points, and 16.8% developed insomnia symptoms in young adulthood. When broken down by race and ethnicity, Black participants made up the biggest share of those with persistent insomnia symptoms, followed by Hispanic/Latino youth.

In particular, compared to non-Hispanic white participants, Black participants were 2.6 times more likely to have insomnia symptoms that persisted through young adulthood. What's more, Black participants had higher odds -- 3.44 times higher -- that their insomnia symptoms would persist rather than resolve after childhood compared to their non-Hispanic white counterparts. What this means is that among Black children whose symptoms continued beyond the transition from childhood to adolescence, their symptoms are less likely to resolve in the transition to adulthood. Hispanic/Latino participants were 1.8 times more likely to have persistent insomnia symptoms compared to white participants.

"We shouldn't wait until someone comes to the clinic as an adult who has suffered from poor sleep all their life. We need to pay more attention to insomnia symptoms in children and adolescents," Fernandez-Mendoza said.

Other Penn State authors on the paper include: Edward Bixler, professor emeritus; Alexandros Vgontzas, professor; Kristina Lenker, assistant professor; Susan Calhoun, associate professor; and Raegan Atha, sleep medicine specialist, all members of the department of psychiatry and behavioral health, Penn State Health Milton S. Hershey Medical Center, Penn State College of Medicine. Jiangang Liao, Fan He and Duanping Liao are all faculty of the department of public health sciences at Penn State College of Medicine. Other authors are Rupsha Singh, postdoctoral fellow at the National Institute on Aging, and Chandra Jackson, senior investigator, National Institute of Environmental Health Sciences of the National Institutes of Health (NIH).

The work was funded by the National Heart, Lung, and Blood Institute, the National Center for Advancing Translational Sciences of the NIH, National Institute of Environmental Health Sciences, National Institute on Aging, National Institute on Minority Health and Health Disparities and the Intramural Programs at the NIH.