A recent study found that early interventions are vital in childhood cases of insomnia, as symptoms do not fully remit in at least 60% of cases.
Insomnia symptoms are more likely to persist from childhood to adulthood than previously believed, according to a study published in Pediatrics. This study aimed to determine the developmental trajectories of insomnia symptoms from childhood to young adulthood to establish whether the sleep disorder persists or developmentally remits as children enter adulthood. The study also aimed to establish how many children saw their symptoms worsen into adult insomnia and whether objective short-sleep duration (OSSD) is a significant determinant of worsening symptoms of insomnia.
The Penn State Child Cohort, a random, population-based study of school-aged children, was used to randomly select 1000 children aged 5 to 12 years for an in-person polysomnograph (PSG) to be used in the study, which 700 children agreed to (visit 1 [V1]). A total of 421 of these participants returned for an in-person follow-up study at ages 12 to 23 years (visit [V2]). A total of 502, aged 18 to 31 years, completed a structured self-reported survey from 2018 to 2021. The study focuses on the 502 individuals with data from that survey.
The length between V1 and V2 in the 421 participants ranged from 5.8 to 13 years; the median length was 7.4 years. The length between V1 and the survey in the 502 participants ranged from 11.4 to 20.3 years, with a median length of 14.8 years. No difference in demographic characteristics was observed between the 3 data points, except for a slight decrease in the proportion of male participants, from 52.7% of the participants in V1 to 48.0% of the respondents to the survey.
At V1 and V2, parents were asked to fill out the Pediatric Behavior Rating Scale and the Pediatric Sleep Questionnaire. At V1, 118 participants were identified as having symptoms of insomnia, defined as a parent report of “often/moderate” to “very often/severe” difficulty initiating and/or maintaining sleep (DIMS) and/or use of sleep medication. At V2, 120 participants had symptoms of insomnia as defined by self-report of DIMS and/or sleep medication use; by the time of the survey, 214 participants identified symptoms of insomnia using the same method. An additional 61 respondents to the survey were identified as having adult insomnia because they answered the question “Do you have insomnia?” in the affirmative.
At V1 and V2, habitual sleep was monitored using an in-laboratory PSG. Participants were monitored from between 21:00 and 23:00 to between 6:00 and 8:00 to adjust as much as possible to their natural sleep schedule. In the survey, all respondents self-reported their total sleep time, and the study investigators calculated that their habitual sleep duration ranged from 3.5 to 11 hours per day, with a mean of 7.1 hours.
The researchers first examined the transitional probabilities of insomnia symptoms between each time point of the visits and survey. They then estimated the developmental trajectories of insomnia symptoms among the 118 participants with childhood insomnia and the developmental trajectories of normal sleep among the 384 participants with normal sleep in childhood. The researchers also examined the percentage of participants in V1 and V2 who developed adult insomnia.
According to the study, 53.7% of participants who had symptoms of insomnia at V1 had symptoms that persisted at V2 and 61.9% did at the survey, whereas 46.3% and 38.1% of participants had remitted at those respective points. Of participants with insomnia symptoms at V2, 57.5% had persistent insomnia symptoms and 42.5% experienced remission by the time of the survey.
A total of 44 participants reported insomnia symptoms at both V1 and V2. Of these, 81.8% had persistent insomnia symptoms and 18.2% had remitted at the time of the survey. Of the 38 participants who had reported insomnia symptoms at V1 and remitted by V2, 60.5% remained remitted and 39.5% relapsed into symptoms of insomnia at the time of the survey.
Among participants with insomnia symptoms at V1, the most frequent predicted trajectory was symptom persistence (43.3%; interquartile range [IQR], 42.4%-44.9% for 1000 imputations), followed by remission (since V1: 26.9%; IQR, 26.3%-28.0%; since V2: 11.2; IQR, 10.2%-11.9%).
Among participants who reported normal sleep at V1, 69.7% remained at normal sleep at V2 and 63.3% remained at normal sleep at the time of the survey, whereas the remaining participants developed symptoms of insomnia. Among participants with normal sleep at V2, 70.4% had normal sleep at the survey, with the remaining participants developing symptoms of insomnia. Among the 76 participants with normal sleep at V1 before they developed insomnia symptoms at V2, 43.4% had their insomnia persist and the remaining 56.6% remitted into normal sleep by the survey.
Among participants with normal sleep at V1, the most frequent predicted trajectory was persistence (48.1%; IQR, 47.7%-48.7%), followed by newly developing insomnia symptoms (20.7%; IQR, 20.0%-21.3%). A total of 22.0% and 20.8% of those with insomnia symptoms at V1 and at V2, respectively, reported adult insomnia in the survey, whereas only 9.4% and 6.6% of participants who reported normal sleep at V1 or V2 reported adult insomnia in the survey.
Insomnia symptoms at V1 were associated with 2.6-fold increased odds of adult insomnia reported in the survey among those with OSSD. Insomnia symptoms at V2 were associated with 5.5-fold increased odds of adult insomnia in the survey among those with OSSD. The odds of adult insomnia at the time of the survey among those with normal sleep duration at V1 or V2 were not significantly increased.
The authors acknowledged that there were limitations to this study. Data on OSSD, obstructive sleep apnea, and periodic limb movements were collected during a 1-night, 9-hour PSG, which may not be representative of habitual sleep. The lack of PSG measures at the survey inhibited the study from examining objective sleep and its trajectory into adulthood. Only self-reported habitual sleep duration could be controlled for in the survey. Although the survey collected complaints of adult insomnia by relying on a previously validated epidemiologic method, the presence of insomnia as defined by diagnostic criteria could not be ascertained at any point with the available self-reported data.
The study concluded that 43% of children with symptoms of insomnia persist with symptoms into young adulthood, more than previously believed. The study also found that 20% of children with insomnia symptoms progress into adult insomnia and that the increased risk is very high (5.5-fold) among those with OSSD.
The authors wrote that pediatricians should consider adolescence a critical period for the prognosis of symptoms of insomnia, particularly for those with OSSD. According to the researchers, early intervention is needed as physicians cannot expect insomnia symptoms to remit, although a sleep study could help identify children with a poor long-term prognosis.
Fernandez-Mendoza J, Lenker K, Calhoun SL, et al. Trajectories of insomnia symptoms from childhood through young adulthood. Pediatrics.2022;149(3):e2021053616. doi:10.1542/peds.2021-053616