Insomnia Found to Be Highly Prevalent Among Adolescents
June 9, 2004
Jennifer Reid Holman

APSS Annual Meeting (Philadelphia) — Insomnia is a widespread and possibly underrecognized problem among U.S. adolescents, according to research presented here at the Associated Professional Sleep Societies annual meeting.

In an epidemiologic study involving face-to-face interviews with 1,014 teenagers aged 13 to 16 years, one third of the adolescents reported having insomnia symptoms at some point during their lives. Of these teens, 94% reported experiencing insomnia symptoms at least twice per week for a month or longer during the prior year. Nearly one third of this group also had a comorbid psychiatric disorder, as defined by the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV).

Nearly 17% of the adolescents met the more strict DSM-IV criteria for insomnia (trouble falling or staying asleep or achieving restorative sleep at least twice a week for a month or more, causing noticeable distress and impairment in their normal functioning). The insomnia appeared to be chronic or frequently recurrent, with a median onset of age 11 years. In addition, 14% of the 13- to 16-year-old interviewees reported an episode of DSM-IV insomnia within the past 30 days.

"The prevalence was a bit surprising," lead investigator Eric Johnson, PhD, a research scientist at the Henry Ford Hospital in Detroit, Michigan, told Medscape. The most common problem was difficulty falling asleep. Sleep efficiency, or time spent in bed actually sleeping, was also a significant problem, he said.

The researchers conducted their prospective study using a sample of children and parent pairs randomly selected from a 400,000-member health maintenance organization group in the tri-county Detroit area. This is the first U.S. epidemiologic study evaluating adolescents using DSM-IV insomnia criteria, Dr. Johnson said.

Sex and socioeconomic level were the only two significant demographic risk factors that surfaced in this study. Lower socioeconomic level correlated with increased DSM-IV insomnia risk, Dr. Johnson told meeting attendees. In addition, girls had a 50% higher risk than boys in this group for lifetime insomnia symptoms.

Dr. Johnson and colleagues also found that pubertal development correlated in a linear fashion with the girls' risk of developing DSM-IV insomnia. There was a "significant jump in insomnia after the onset of menses," he said, with girls being 2.5 times more likely to experience insomnia after menses than before its onset. This was also the point at which the incidence rate of insomnia for girls diverged from boys in their age group.

The investigators assessed stages of pubertal development with an established self-report measure that relied on the adolescents' feedback regarding various physiologic changes.

Of the boys experiencing DSM-IV insomnia, no association was found with their pubertal development. And in both groups, no significant difference in insomnia prevalence was traced to race/ethnicity or parents' marital status.

Parents also underwent separate interviews regarding their children's sleep habits in this investigation. "The agreement between kids and parents is not good," Dr. Johnson told Medscape. "It's on the order of a lot of the other internal mood states like depression and anxiety in adolescence.... In short, it doesn't appear the parents typically know [about the symptoms]."

The second phase of this study is underway, with 400 of the adolescents with DSM-IV insomnia being followed after two years, now aged 15 to 18 years.

This research was funded by the National Institutes of Health.

APSS 18th Annual Meeting: Abstract 250. Presented June 8, 2004.