Childhood sleep is prospectively associated with adolescent alcohol and marijuana use.

INTRODUCTION: Prior studies have examined the cross-sectional relationship between adolescent sleep and substance use; however, fewer have explored the long-term connections between childhood sleep and adolescent substance use. METHODS: This study investigated both cross-sectional associations during adolescence and prospective associations between childhood weeknight sleep and later alcohol and marijuana use in the Future of Families and Child Wellbeing Study, a diverse national birth cohort of urban children from 20 cities with populations greater than 200,000. Parents reported their child's bedtime at ages 3, 5, and 9 and their child's sleep duration at ages 5 and 9. RESULTS: At age 15, adolescents self-reported their bedtime, sleep duration, and alcohol and marijuana use (n = 1514). Logistic regression analyses for each substance use outcome at age 15 were adjusted for sex, age at time of assessment, race/ethnicity, income-relative-to-poverty threshold, family structure, and caregiver education level. At age 15, later bedtime (AOR=1.39; 95 % CI=1.22, 1.57) and shorter sleep duration (AOR=1.28; 95 % CI=1.14, 1.43) were associated with greater odds of consuming a full drink of alcohol more than once, and later bedtime was associated with greater odds of trying marijuana (AOR=1.35; 95 % CI=1.20, 1.51). Unexpectedly, later bedtimes at age 3 were associated with lower odds of drinking alcohol by age 15 (AOR=0.74; 95 % CI=0.59, 0.92). In contrast, later bedtimes at age 9 were associated with greater odds of drinking alcohol (AOR=1.45; 95 % CI=1.11, 1.90). Additionally, later bedtime at age 5 (AOR=1.26; 95 % CI=1.01, 1.58) and shorter sleep duration at age 9 (AOR=1.19; 95 % CI=1.04, 1.36) were associated with greater odds of trying marijuana. CONCLUSION: Taken together, these associations support the importance of protecting childhood sleep habits to reduce the likelihood of substance use starting as early as mid-adolescence. IMPLICATIONS AND CONTRIBUTION: In this longitudinal cohort study, adolescents were more likely to have consumed alcohol or tried marijuana by age 15 if they had later bedtimes and shorter sleep duration during childhood and adolescence. Protecting sleep health throughout childhood may reduce the likelihood of substance use during early adolescence.

The impact of screen use on sleep health across the lifespan: A National Sleep Foundation consensus statement.

OBJECTIVE: To achieve consensus on whether screen-based digital media (1) in general, (2) via prebedtime content, and (3) via prebedtime light impairs sleep health in (a) childhood, (b) adolescence, and (c) adulthood. Furthermore, to address whether employing behavioral strategies and interventions may reduce the potential negative effects of screens on sleep health. METHODS: The National Sleep Foundation convened a 16-person multidisciplinary expert panel ("Panel"). Panelists met virtually 5 times throughout 2023, during which they followed a modified Delphi RAND/UCLA Appropriateness Method to reach consensus. RESULTS: The Panel conducted a literature review starting with 2209 articles, narrowed down to 522 relevant empirical articles and 52 relevant review articles. The search was refined to include 35 experimental/intervention studies that examined whether there was a causal link between screen-based digital media and sleep. In addition, panelists reviewed 5 recent relevant systematic review articles. After reviewing the summarized current literature, panelists voted on 10 candidate statements about whether screen use impairs sleep health. The Panel met virtually to discuss the results of the first round of votes, which was then followed by a second round of voting, ultimately achieving consensus on 5 out of the 10 statements. CONCLUSIONS: The Panel achieved consensus that (1) in general, screen use impairs sleep health among children and adolescents, (2) the content of screen use before sleep impairs sleep health of children and adolescents, and (3) behavioral strategies and interventions may attenuate the negative effects of screen use on sleep health.

Actigraphic sleep dimensions and associations with academic functioning among adolescents.

STUDY OBJECTIVES: There is mixed evidence regarding associations of sleep duration with academic functioning in adolescents and a lack of research on other sleep dimensions, particularly using objective sleep measures. We examined associations of multiple actigraphic sleep dimensions with academic functioning among adolescents. METHODS: Data were from the sleep sub-study of the age 15 wave of the Future of Families and Child Wellbeing Study (n = 774-782; 52% female), a national, diverse sample of teens. Adolescents wore wrist-actigraphs for ~1 week and completed a survey reporting academic performance and school-related behavioral problems. Regression models assessed whether average sleep duration, timing, maintenance efficiency, and SD-variability were associated with self-reported academic functioning in cross-sectional analyses adjusted for demographic characteristics, depressive symptoms, and anxious symptoms. RESULTS: Later sleep timing (hours) and greater sleep variability (SD-hours) were associated with poorer academic outcomes, including sleep onset variability with higher odds of receiving a D or lower (OR = 1.29), sleep onset (ß = -.07), sleep offset (ß = -.08), and sleep duration variability (ß = -.08) with fewer A grades, sleep offset with lower GPA (ß = -.07), sleep offset (OR = 1.11), sleep duration variability (OR = 1.31), and sleep onset variability (OR = 1.42) with higher odds of being suspended or expelled in the past 2 years, and sleep duration variability with greater trouble at school (ß = .13). Sleep duration, sleep maintenance efficiency, and sleep regularity index were not associated with academic functioning. CONCLUSIONS: Later sleep timing and greater sleep variability are risk factors for certain academic problems among adolescents. Promoting sufficient, regular sleep timing across the week may improve adolescent academic functioning.

Effects of a 1-hour per night week-long sleep extension in college students on cardiometabolic parameters, hydration status, and physical activity: A pilot study.

OBJECTIVES: Short sleep duration is associated with poor physical health in college students. Few studies examine the effects of sleep extension on physical health in this population, who are susceptible to sleep loss. We examined health effects of a 1-week, 1-hour nightly sleep extension in college students. METHODS: Twelve healthy undergraduate college students (83% female; age 20.2 ± 1.5years) completed a study consisting of sleeping typically for 1week ("Habitual"), then extending sleep by ≥1 hour/night during the second week ("Extension"). Sleep and physical activity actigraphy were collected throughout. Following each week, participants completed cardiometabolic assessments including a meal response and provided a urine sample for markers of hydration. RESULTS: In Extension compared to Habitual, average sleep duration increased (mean change±SEM, +42.6 ± 15.1 minutes; p = .005), while subjective sleepiness (-1.8 ± 0.8 units; p = .040), systolic blood pressure (-6.6 ± 2.8 mmHg; p = .037), postprandial glucose area under the curve (-26.5 ± 10.2 mg/dL × h; p = .025) and time to baseline (-83.0 ± 46.4 minutes; p = .031) after the meal response, sedentary time (-44.3 ± 15.7 minutes; p = .018), and percentage of wake in moderate-to-vigorous activity (-0.89% ± 0.35%; p = .030) decreased. Participants who increased average sleep duration by ≥20 minutes (n = 9) were better hydrated according to urine osmolality (-187.0 ± 68.4 mOsm/kg; p = .026) and specific gravity (-0.01 ± 0.002 g/mL; p = .012) and had reduced odds of dehydration according to urine osmolality (≥800 mOsm/kg; -67%; OR=0.03; p = .035). CONCLUSIONS: This pilot study's findings suggest that sleep extension may improve cardiometabolic functioning and hydration, and alter sedentary behavior and physical activity, in college students. Sleep extension may be employed to improve multiple aspects of health in this sleep-deprived population.

Entrainment to gradual vs. immediate 8-hour phase advance shifts with and without short-wavelength enriched polychromatic green light.

OBJECTIVES: For optimal health and well-being the sleep episode and the circadian timing system should be properly aligned. We evaluated the effectiveness of different dynamic light and sleep/wake shift schedules for rapid circadian entrainment following an 8-hour advance of sleep. METHODS: Forty-three healthy participants completed an 8-day inpatient protocol in which the 8-hour sleep episode was advanced by 8 hours. Participants were assigned to one of five conditions: (1) dim ambient WHITE light and GRADUAL shift in which the sleep episode was incrementally advanced over 5days; (2) dim GREEN, short-wavelength (∼504 nm) polychromatic light and GRADUAL shift; (3) dim WHITE light and SLAM shift, including an abrupt 8-hour advance on day 3 following an extended 32-hour wake episode; (4) GREEN light and SLAM shift; or (5) COMBINED (higher illuminance WHITE plus GREEN) light and modified SLAM shift with 2 short naps scheduled on the day prior to the abrupt advance. Phase shifts of the plasma dim light melatonin onset and sleep measures were compared to examine effects of protocol condition. RESULTS: After 5days, the COMBINED light/modified SLAM shift condition showed larger phase advances of dim light melatonin onset (4.02 ± 1.13 hours) compared to the other 4 conditions (range 1.50 ± 0.96-2.83 ± 2.23 hours; p < .05) and resulted in increased REM sleep duration and fewer sleep disruptions. CONCLUSIONS: Consideration of the type of shift and the illuminance and wavelength of light may assist in designing lighting countermeasures to sleep and circadian disruption, which has implications for jetlag, shiftwork, and circadian rhythm sleep disorders.

Interactive Screen-Based Activities Predict Worse Actigraphic Sleep Health That Night Among Adolescents.

PURPOSE: To determine the micro-longitudinal effects of duration and timing of screen-based activities on sleep within and between adolescents. METHODS: Daily survey and actigraphy data from the age 15 wave of the Future of Families and Child Wellbeing Study were analyzed using multilevel modeling. Four hundred seventy five adolescents provided three or more days of valid daily survey and nighttime sleep data. RESULTS: Within-person results showed that on days when adolescents played video games more than their daytime average ± SE (1.3 ± 1.2 hours), sleep onset (6 ± 2 minutes, p < .01) and midpoint (4 ± 2 minutes, p < .02) were delayed for each additional hour of gaming. Between-person results showed that for each hour adolescents used screens to communicate with friends across the day, sleep onset was later (11 ± 3 minutes, p < .01), sleep midpoint was later (8 ± 3 minutes, p < .01), and sleep duration was shorter (-5 ± 2 minutes, p < .03). Adolescents who used screens to communicate with friends or play video games in the hour before bed had later sleep onset (30 ± 14 minutes, p < .03) and midpoint (25 ± 13 minutes, p < .05). DISCUSSION: Among adolescents, passive screen usage such as browsing the Internet or watching videos may not affect sleep timing or duration, but limiting interactive screen-based activities could protect adolescent sleep health and well-being.

Actigraphic Sleep Variability is Associated With Lower Positive Mood in Adolescents.

PURPOSE: Poor sleep health is associated with lower positive mood in adolescents, and more variable sleep is associated with more negative mood. There is a lack of research on the associations between sleep variability and positive mood in adolescents. We investigated whether several types of sleep variability, measured with actigraphy, were associated with positive mood reported on a daily diary in adolescents. METHODS: Data were collected from a substudy of the Year 15 wave of the Future of Families and Child Wellbeing Study (n = 580; 53% female, mean age ± standard deviation [SD] = 15.4 ± 0.5 years, range 14.7-17.7). Adolescents wore an actigraphy device (M ± SD = 5.6 ± 1.4 nights per adolescent, range: 3-10) and completed daily diaries (M ± SD = 5.5 ± 1.4 days per adolescent, range: 3-9) for ∼1 week, where they rated their levels of happiness and excitement during that day from 0 (not at all) to 4 (extremely). Happiness and excitement were averaged into "positive mood." Separate linear regression models assessed whether actigraphy-measured variability of sleep duration, onset, and offset (residual individual standard deviation, riSD), sleep regularity index, social jetlag, and free night catch-up sleep were associated with average positive mood per person. Analyses adjusted for age, birth sex, race/ethnicity, household income, and the primary caregiver's education level. RESULTS: Greater variability in sleep duration (p = .011, ß = -0.11) and lower sleep regularity index (p = .034, ß = 0.09) were associated with lower ratings of positive mood. There were no other significant associations (p ≥ .10). DISCUSSION: Variable and irregular sleep are associated with lower levels of positive mood in adolescence, which may increase the risk of poor emotional health in adulthood.

Recovery Sleep After Sleep Restriction Is Insufficient to Return Elevated Daytime Heart Rate and Systolic Blood Pressure to Baseline Levels.

OBJECTIVE: Sleep restriction alters daytime cardiac activity, including elevating heart rate (HR) and blood pressure (BP). There is minimal research on the cumulative effects of sleep loss and the response after subsequent recovery sleep on HR and BP. This study examined patterns of HR and BP across baseline, sleep restriction, and recovery conditions using multiple daytime cardiac measurements. METHODS: Participants (15 healthy men, mean [standard deviation] = 22.3 [2.8] years) completed an 11-day inpatient protocol with three nights of 10 hours/night baseline sleep opportunity, five sleep restriction nights (5-hour/night sleep opportunity), and two recovery nights (10-hour/night sleep opportunity). Resting HR and BP were measured every 2 hours during wake. Multilevel models with random effects for individuals examined daytime HR and BP across study conditions and days into the study. RESULTS: Mean daytime HR was 1.2 (0.5) beats/min lower during sleep restriction compared with baseline ( p < .001). During recovery, HR was 5.5 (1.0) beats/min higher ( p < .001), and systolic BP (SBP) was 2.9 (1.1) mm Hg higher ( p = .009). When accounting for days into the study (irrespective of condition) and measurement timing across the day, HR increased by 7.6 beats/min and SBP increased by 3.4 mm Hg across the study period ( p < .001). CONCLUSIONS: Our findings suggest that daytime HR and SBP increase after successive nights of sleep restriction, even after accounting for measurement time of day. HR and SBP did not recover to baseline levels after two recovery nights of sleep, suggesting that longer recovery sleep may be necessary to recover from multiple, consecutive nights of moderate sleep restriction.

Worse sleep health predicts less frequent breakfast consumption among adolescents in a micro-longitudinal analysis.

BACKGROUND: Poor self-reported sleep health has been linked to not consuming breakfast in adolescents, but it is unknown whether poor sleep measured objectively predicts next-day breakfast consumption within adolescents. We investigated within- and between-person associations of objectively measured sleep dimensions and subjective sleep quality with adolescent breakfast consumption. METHODS: Data were collected from a micro-longitudinal substudy of the Year 15 wave of the Fragile Families and Child Wellbeing Study (n = 590). Adolescents wore an actigraphy device and completed daily diaries for ~ 1 week (M ± SD = 5.6 ± 1.4 nights per adolescent, range: 3-9), where they rated their sleep quality and reported whether they had eaten breakfast that day, with no specific definition of breakfast provided (M ± SD = 5.5 ± 1.4 days per adolescent, range: 3-9). Separate mixed models assessed whether actigraphy-measured sleep duration (linear and quadratic, sleep duration x sleep duration), timing, maintenance efficiency, and subjective quality predicted odds of breakfast consumption both within and between adolescents. Variability of sleep duration and timing (standard deviation per person), sleep regularity index (SRI), and social jetlag were tested as additional between-person predictors. Analyses with predictors other than sleep duration were adjusted for sleep duration. RESULTS: Following nights when adolescents had shorter or longer sleep duration (p = .005; curvilinear association), later sleep onset, or later sleep midpoint (both p = .025) than their own usual, they had lower odds of consuming breakfast the next day (within-person associations). Adolescents who on average had later sleep onset (p = .013) or midpoint (p = .013) or who reported lower sleep quality (p = .011) had lower average odds of consuming breakfast (between-person associations). Adolescents with greater variability of sleep duration (p = .005), midpoint (p = .004), or offset (p < .001) had lower average odds of consuming breakfast (between-person associations). Sleep maintenance efficiency (within or between adolescents), SRI, and social jetlag were not associated with breakfast consumption (all p > .10). CONCLUSIONS: Multiple dimensions of sleep health are associated with breakfast consumption, both within and between adolescents. Poor sleep and dietary behaviors in adolescence may negatively impact future metabolic health.

Secondhand smoke exposure is longitudinally associated with shorter parent-reported sleep duration during childhood.

BACKGROUND: Secondhand smoke exposure has been cross-sectionally associated with worse sleep health outcomes in children and shorter sleep duration in adolescents. OBJECTIVES: We assessed longitudinal and cross-sectional associations between secondhand smoke (SHS) exposure and shorter sleep duration in children from the Fragile Families and Child Wellbeing Study, a longitudinal birth cohort. We additionally examined whether associations would persist after controlling for potential confounders. PARTICIPANTS: Mothers (n = 4898) were recruited using a stratified random sample of large United States cities and oversampling for nonmarital births. MEASUREMENTS: Mothers were asked about whether they smoked during pregnancy, whether their child spent time with someone who is smoking, and their child's weekday sleep duration. Sociodemographic factors, asthma diagnosis, and bedtime routines were assessed as potential confounders. Data collected at ages 3, 5, and 9 years were analyzed using multivariable regression models (N = 1912; 51.6% boys). RESULTS: SHS exposure at age 3 predicted 15.0 fewer minutes at age 5 (P = .001) and 12.3 fewer minutes at age 9 (P = .003). SHS exposure at age 9 was cross-sectionally associated with 14.4 fewer minutes of sleep duration at age 9 (P = .002). Findings persisted after controlling for potential confounders. CONCLUSION: These results provide associational support for the hypothesis that SHS exposure may have long-term consequences for childhood sleep duration. Future studies should investigate the relationship between SHS exposure and shorter sleep duration using objective measurements of serum cotinine and sleep actigraphy and by exploring potential mechanisms.

Too Jittery to Sleep? Temporal Associations of Actigraphic Sleep and Caffeine in Adolescents.

Caffeine consumption has been linked to poor sleep health in adolescents, but it is unknown whether poor sleep predicts caffeine consumption, and/or whether caffeine consumption predicts poor sleep, particularly when sleep is measured objectively. Data were collected from a micro-longitudinal sub-study of the age 15 wave of the Fragile Families and Child Wellbeing Study (n = 589). Adolescents wore an actigraphy device and completed daily surveys for ~1 week. Daily surveys assessed subjective sleep quality and caffeinated beverage consumption (0 = no caffeine, 1 = any caffeine). Separate mixed models assessed whether actigraphy-measured sleep duration, timing, maintenance efficiency, and subjective quality predicted next-day caffeinated beverage consumption within and between adolescents. Variability (standard deviation) of sleep duration and timing, sleep regularity index, and social jetlag were tested as additional between-person predictors. Lagged models tested whether daily caffeinated beverage consumption predicted sleep that night (n = 458). Adolescents with more variable sleep duration and midpoint had higher average odds of consuming caffeinated beverages compared to others. After adolescents consumed ≥1 caffeinated beverage, they had later sleep onset that night and wake time the next morning than usual versus when they did not consume caffeine. Curbing caffeinated beverage consumption may aid in the maintenance of regular sleep schedules and advance sleep timing in adolescents.

Validity of Actigraphy in Young Adults With Insomnia.

Objective/Background: Actigraphy is an inexpensive and objective wrist-worn activity sensor that has been validated for the measurement of sleep onset latency (SOL), number of awakenings (NWAK), wake after sleep onset (WASO), total sleep time (TST), and sleep efficiency (SE) in both middle-aged and older adults with insomnia. However, actigraphy has not been evaluated in young adults. In addition, most previous studies compared actigraphy to in-lab polysomnography (PSG), but none have compared actigraphy to more ecologically valid ambulatory polysomnography.Participants: 21 young adults (mean age = 19.90 ± 2.19 years; n = 13 women) determined to have chronic primary insomnia through structured clinical interviews.Methods: Sleep diaries, actigraphy, and ambulatory PSG data were obtained over a single night to obtain measures of SOL, NWAK, WASO, time spent in bed after final awakening in the morning (TWAK), TST, and SE.Results: Actigraphy was a valid estimate of SOL, WASO, TST, and SE, based on significant correlations (r = 0.45 to 0.87), nonsignificant mean differences between actigraphy and PSG, and inspection of actigraphy bias from Bland Altman plots (SOL α = 1.52, WASO α = 7.95, TST α = -8.60, SE α = -1.38).Conclusions: Actigraphy was a valid objective measure of SOL, WASO, TST, and SE in a young adult insomnia sample, as compared to ambulatory PSG. Actigraphy may be a valid alternative for assessing sleep in young adults with insomnia when more costly PSG measures are not feasible.

Associations Between Sleep and Health-Risk Behaviors in a Rural Adolescent Population.

INTRODUCTION: Insufficient sleep has been associated with engagement in a number of health-risk behaviors in adolescents, including substance use and sexual activity. Associations between sleep and health-risk behaviors in adolescents living in rural areas of the United States are not well investigated. In rural settings, adolescents' sleep patterns, lifestyle factors, and health-risk opportunities may differ from those of urban adolescents, making the independent study of sleep and health behavior associations necessary. METHOD: This study examined data from the Rural Adolescent Health Survey (N = 322) administered in rural North Dakota. RESULTS: Rural adolescents who reported engaging in smoking, alcohol use, or drug use slept significantly less than adolescents who did not report engaging in these activities. DISCUSSION: Sleep was not associated with chewing tobacco use or risky sexual activity, which may reflect an effect of rural cultural values on sleep and health-risk behavior associations.