Insufficient sleep duration and bedtime inconsistency were independently associated with serious cognitive difficulty among US adolescents, supporting multidimensional sleep health frameworks emphasizing the combined importance of sleep duration and bedtime consistency for adolescent cognitive functioning.
Key Findings
Results
Concussion history was associated with more than twice the odds of serious cognitive difficulty in fully adjusted models.
Adjusted odds ratio for concussion history: aOR = 2.07, 95% CI = 1.72–2.48
Analysis used sequential multivariable models accounting for complex sampling from the 2022–2024 National Survey of Children's Health
Sample consisted of adolescents aged 12–17 years in a nationally representative cross-sectional dataset
Concussion-related interaction terms (e.g., concussion × sleep variables) were not statistically significant
Results
Short sleep duration was independently associated with greater odds of serious cognitive difficulty among US adolescents.
Adjusted odds ratio for short sleep duration: aOR = 1.27, 95% CI = 1.11–1.46
Finding held in fully adjusted models controlling for concussion history, bedtime inconsistency, physical activity, ACE burden, and caregiver capacity
A statistically significant interaction between short sleep and bedtime inconsistency was identified (Wald F = 4.35, p = .037)
Results
Bedtime inconsistency was independently associated with greater odds of serious cognitive difficulty among US adolescents.
Adjusted odds ratio for bedtime inconsistency: aOR = 1.42, 95% CI = 1.22–1.65
Finding was independent of sleep duration, concussion history, and other covariates in fully adjusted models
Sensitivity analyses evaluated alternative bedtime consistency operationalizations, supporting robustness of the finding
Results
Lack of sports participation was associated with approximately twice the odds of serious cognitive difficulty.
Adjusted odds ratio for no sports participation: aOR = 2.05, 95% CI = 1.81–2.33
Insufficient physical activity was also independently associated with serious cognitive difficulty (aOR = 1.32, 95% CI = 1.09–1.58)
Both sports participation and physical activity were included as separate covariates in the sequential multivariable models
Results
Lower caregiver capacity was associated with approximately twice the odds of serious cognitive difficulty.
Adjusted odds ratio for lower caregiver capacity: aOR = 2.04, 95% CI = 1.80–2.31
Greater adverse childhood experience (ACE) burden was also associated with greater odds of serious cognitive difficulty
Both ACE burden and caregiver capacity were included as covariates in fully adjusted models
Results
A statistically significant interaction between short sleep duration and bedtime inconsistency on serious cognitive difficulty was identified.
Wald F = 4.35, p = .037 for the short sleep × bedtime inconsistency interaction term
This was identified in exploratory analyses
Adjusted predicted probabilities demonstrated 'substantial cumulative neurobehavioral vulnerability across multidimensional sleep health and concussion-risk profiles'
Concussion-related interaction terms were not statistically significant
Methods
The study used cross-sectional data from a nationally representative sample of US adolescents aged 12–17 years from the 2022–2024 National Survey of Children's Health.
Sequential multivariable models accounted for complex sampling design
Key exposures included concussion history, short sleep duration, bedtime inconsistency, sports participation, and physical activity
Outcome was serious cognitive difficulty
Sensitivity analyses evaluated alternative bedtime consistency operationalizations and interaction effects
What This Means
This research suggests that among American teenagers, several factors are independently linked to serious difficulty with thinking and cognition. Using a large, nationally representative survey of adolescents aged 12–17 conducted between 2022 and 2024, the study found that not getting enough sleep, having inconsistent bedtimes, having a history of concussion, not participating in sports, and not getting enough physical activity were all associated with higher odds of serious cognitive difficulty. Importantly, both sleep duration and sleep regularity mattered on their own — teenagers who had both short sleep and inconsistent bedtimes appeared to face compounded risk.
Some of the associations were striking in their size. Adolescents with a concussion history had about twice the odds of serious cognitive difficulty compared to those without one, and those who did not participate in sports also had about twice the odds. Lower caregiver capacity and greater exposure to adverse childhood experiences were additional risk factors. The study also found a statistically significant interaction between short sleep and inconsistent bedtimes, meaning these two sleep problems together may be especially harmful for cognitive functioning.
This research suggests that efforts to support teenagers' brain health should consider not just how long adolescents sleep, but also how consistent their sleep schedules are. Public health and clinical approaches that address multiple dimensions of sleep health — including both duration and regularity — alongside concussion prevention, physical activity promotion, and caregiver support may be most beneficial for adolescent cognitive well-being. Because this was a cross-sectional study, it cannot establish that these factors directly cause cognitive difficulty, only that they are associated with it.
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Knowlden A. (2026). Multidimensional sleep health and serious cognitive difficulty among US adolescents.. Journal of clinical sleep medicine : JCSM : official publication of the American Academy of Sleep Medicine. https://doi.org/10.1007/s44470-026-00155-y