Effect of Sleep Restriction on Adolescent Cognition by Adiposity: A Randomized Crossover Trial.

Importance: Pediatric obesity is associated with impaired cognitive function; however, the mechanisms underlying this association demand assessment. Sleep may be a relevant moderator, as poor sleep predicts both increased adiposity and impaired cognitive function. Objective: To determine the effects of adiposity and sleep on adolescent cognitive function. Design, Setting, and Participants: This single-blind randomized crossover trial was conducted from September 2020 to October 2022. Parents or caregivers provided demographic information for adolescent participants. Body mass index percentile and bioelectrical impedance analysis assessed adiposity. Adolescents completed 2 actigraphy-confirmed sleep conditions, adequate and restricted, followed by in-person cognitive assessment. No additional follow-up was provided. Data collection for this population-based study took place in a behavioral medicine clinic in Birmingham, Alabama. A total of 323 participants were assessed for eligibility (ages 14-19 years and healthy). Of the 244 eligible adolescents, 157 declined participation. Eighty-seven were randomized and 26 dropped out postenrollment. The final sample included 61 adolescents, 31 with healthy weight and 30 with overweight or obesity. Data were analyzed from April to October 2023. Interventions: Following a 2-day washout period of adequate sleep, adolescents completed 2 sleep conditions: adequate (mean [SD] duration, 8 hours, 54 minutes [58.0 minutes]) and restricted (mean [SD] duration, 4 hours, 12 minutes [50.7 minutes]). Main Outcomes and Measures: The National Institutes of Health Cognitive Toolbox assessed global and fluid cognition, cognitive flexibility, working and episodic memory, attention, and processing speed. The Stroop Task assessed inhibition. Results: The final sample included 61 adolescents (mean [SD] age, 16.3 [1.6] years; 35 [57.4%] female). Restricted sleep predicted poorer global cognition scores (restricted mean [SD], 98.0 [2.8]; adequate mean [SD], 103.2 [2.9]), fluid cognition scores (restricted mean [SD], 94.5 [3.2]; adequate mean [SD], 102.0 [3.6]), and cognitive flexibility scores (restricted mean [SD], 84.8 [3.0]; adequate mean [SD], 92.8 [3.0]) for adolescents with overweight or obesity. No differences emerged for adolescents with healthy weight. Adolescents with overweight or obesity also had poorer attention scores (mean [SD], 80.0 [2.3]) compared to adolescents with healthy weight (mean [SD], 88.4 [SD, 2.3]) following restricted sleep. No differences emerged following adequate sleep. Findings were similar for total body fat percentage (TBF%); however, for adolescents with TBF% above 42, restricted sleep also predicted poorer processing speed, and the association between sleep and attention did not vary based on TBF%. Conclusions and Relevance: Adolescents with overweight or obesity may be more vulnerable to negative cognitive effects following sleep restriction. Improved sleep hygiene and duration in this group may positively impact their cognitive health. Trial Registration: ClinicalTrials.gov Identifier: NCT04346433.

Sleep and Inflammation during COVID-19 Virtual Learning in Adolescents with Overweight or Obesity.

(1) Background: Adolescents present as a high-risk group for a range of adverse physical health outcomes during the pandemic, including sleep and C-reactive protein (CRP) levels. As adolescents with overweight or obesity (OWOB) present as an even higher risk group, the present study assessed relationships between sleep and CRP levels before and during COVID-19 in adolescents with OWOB. (2) Methods: Fourteen adolescents with OWOB participated in a pre-COVID1, pre-COVID2, and during-COVID-19 lab visit, measuring sleep and CRP levels. The sample size was limited by the number of participants who provided data before COVID-19 and who were enrolled in virtual school during the recruitment phase. However, our power analyses indicated needing a minimum of 10 participants to achieve adequate power. Pre-COVID1, pre-COVID2, and during-COVID-19 normative expected CRP levels were calculated based on age, sex, race, and body mass index percentile-matched data. Analyses compared pre-COVID1 and pre-COVID2 sleep with during-COVID-19 sleep, during-COVID-19 sleep and during-COVID-19 CRP levels, during-COVID-19 CRP levels with normative expected during-COVID-19 CRP levels, change in CRP levels from pre-COVID1 and pre-COVID2 to during-COVID-19 with normative expected CRP levels during those time periods, and change in CRP levels before COVID-19 with change in CRP levels during COVID-19. (3) Results. During COVID-19, participants experienced decreased sleep efficiency (p = 0.001), later wake time (p < 0.001), longer time in bed (p = 0.021), and onset latency (p = 0.004), compared to pre-COVID1, and decreased sleep efficiency (p = 0.002), longer onset latency (p = 0.006), and later wake time (p < 0.001) and bedtime (p = 0.016) compared with pre-COVID2. During-COVID-19 CRP levels were positively correlated with during-COVID-19 wake times (p = 0.01) and times in bed (p = 0.008). During-COVID-19 CRP levels were greater than normative expected CRP levels (p < 0.001). CRP levels increased more from pre-COVID1 and pre-COVID2 to during-COVID-19 than normative expected changes in CRP levels (p < 0.003). Changes in CRP levels before and during COVID-19 were not significantly different. (4) Conclusions. These findings highlight the consequential effects of COVID-19, including impairments in sleep, on adolescents with OWOB. CRP levels increased more (~5 mg/L) during COVID-19 than normative expected change.

The Effects of COVID-19 Virtual Learning on Body Fat and Insulin Resistance in Adolescents with Overweight or Obesity.

(1) Background: COVID-19 virtual learning reduced structural supports for adolescent physical activity and diet, threatening metabolic health, especially in teens with overweight or obesity (OWOB). (2) Methods: Adolescents (N = 14) with OWOB completed fasting blood draws (measuring insulin resistance, IR) and Dual Energy X-Ray Absorptiometry (DXA, measuring total body fat percent, TBF%) pre-COVID-19 and during COVID-19. Changes in TBF% and IR were calculated (1) pre-COVID-19 and (2) from pre-COVID-19 to during COVID-19. Age and body mass index (BMI) percentile-matched data assessed normative changes across similar, non-COVID-19 time periods. Paired t-tests compared TBF% change pre- to during COVID-19 with (1) TBF% change pre-COVID19 and (2) TBF% normative change. Two ANCOVAs compared IR change pre- to during COVID-19 with (1) IR change pre-COVID-19 controlling for BMI z-score and difference in time between assessments and (2) normative change in IR controlling for sex/race. (3) Results: The TBF% change pre-COVID-19 and the normative change were similar. The TBF% increased more (~six percentage points) during COVID-19 compared to normative change (p < 0.01). During COVID-19, IR increased more (~2.5 units) than change pre-COVID-19 (p = 0.03) and increased more (~3.5 units) than normative change (p = 0.01). (4) Conclusions: TBF% and IR increased exponentially during COVID-19 in teens with OWOB compared to pre-COVID-19 and normative changes.

The Impact of Longitudinal Patterns of Adolescent Sleep Duration on Adult C-Reactive Protein (CRP), Waist-To-Height Ratio, and Body Mass Index (BMI) Among Black and White Individuals.

PURPOSE: To assess the impact of longitudinal adolescent sleep duration on adult C-reactive protein (CRP), waist-to-height ratio (WtHR), and body mass index (BMI) by race. METHODS: Participants (N = 2,399; Mage = 15.7; 40.2% male; 79.2% White, 20.8% Black; Grades 7-12 at Wave I) from the Add Health database provided self-reported sleep duration in Waves I-IV. During Wave V, CRP, WtHR, and BMI were objectively measured. Trajectory analysis was performed using a group-based modeling approach. Chi-square test determined racial differences between groups. General linear models determined relationships between trajectory group, race, and group/race interaction with Wave V CRP, WtHR, and BMI. RESULTS: Three sleep trajectories emerged: Group 1 "shortest" (24.4%), Group 2 "stable recommended" (67.6%), and Group 3 "varied" (8%). Black individuals and older individuals were more likely to be in Group 1 compared with Group 2. Regardless of race, individuals with patterns of sleep duration increasing to above what is recommended across waves (Group 3) had elevated CRP. Individuals with stable patterns of adequate sleep (Group 2) had lower WtHR. Black individuals with consistently stable patterns of adequate sleep duration had lower BMI compared to those with low sleep duration. DISCUSSION: Black individuals were more likely to obtain chronically short sleep during the transition from adolescence to adulthood, highlighting a significant health disparity. Poor longitudinal sleep predicted elevated CRP and WtHR. Sleep only impacted BMI for Black individuals. This may relate to racial differences in BMI measurement.