Sleep and Stigma: Novel Moderators in the Relationship Between Weight Status and Cognitive Function

Study Overview
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Brief Summary
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The investigators aim to assess the relationship between overweight/obesity and decreased cognitive function in adolescents. While this relationship has been seen in past literature, the causal mechanisms are still unclear. Thus, the present study will assess sleep and stigma as possible moderators. As sleep is related to both weight and cognitive abilities it may be an important factor in the relationship between these two variables. Further, people with overweight/obesity have higher risk for stigma experiences which may increase inflammation through chronic stress and elevated cortisol. Because inflammation is theorized to play a role in the relationship between elevated BMI and decreased cognitive function, stigma may be an important moderator. 60 adolescent participants will complete two sleep conditions (adequate and restricted) in a randomized order, each followed by a lab visit during which participants will complete a short cognitive battery. At these visits, participants will also be given a self serve breakfast with a variety of whole and processed food options to further evaluate the relationship between overweight/obesity, sleep, nutritional intake, and cognitive function.

Detailed Description
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Obesity represents one of our nation's leading public health issues. In 2017, over 30% of U.S. high school students had either overweight (15.6%) or obesity (14.8%), and the average U.S. BMI continues to rise. Overall, this increasing trend is associated with earlier mortality and lower quality of life. In 2005 it was projected that if current U.S. weight trends continued, the average lifespan would decrease by about 9 months. Documented declines exceed this calculation, with rises in BMI relating to an estimated 11-month decrease in life expectancy in 2011. In adolescents specifically, this epidemic shares associations with many negative health outcomes including poorer sleep quality, impaired academic performance, and lower cognitive function. Thus, it is imperative that researchers work to understand the complex nature of this preventable disease and recognize its significant longitudinal health implications. One factor significantly related to overweight/obesity (OWOB) is decreased cognitive function. However, the causal nature of this relationship is unclear. It has been hypothesized that impaired cognitive function and poor inhibition could predict increased food consumption, thus contributing to the association between cognitive deficits and OWOB. Alternatively, it has been suggested that biological factors stemming from obesity (i.e. low grade inflammation, insulin resistance, low blood flow, and increased levels of cytokines and leptin) work to exacerbate preexisting cognitive impairments, or are perhaps fully responsible for the cognitive deficits seen in individuals with OWOB. Thus, further research is needed to clarify these relationships. Research regarding OWOB and cognitive function has left a critical gap in the literature by failing to consider the role of sleep within this relationship. Current evidence shows that more than 2/3 of adolescents fail to attain the recommended minimum of 8 hours of sleep during the week. However, a meta-analysis found that every added hour of sleep that adolescents do secure relates to a 9.0% decrease in obesity risk. In line with this finding, sleep restriction is associated with increased appetite, hunger, and poorer nutritional food choices. Sleep restriction has also been tied to impairments in cognitive function including decreased working memory and attention. Thus, it is possible that the relationship between OWOB and cognitive function in adolescents is influenced by sleep behaviors. Another important factor to consider in the relationship between OWOB and cognitive function is stigma. Weight stigma is a pervasive problem with multiple implications for physical health. For example, chronic low-grade inflammation represents a known correlate of chronic stress and stigmatization. This is significant as elevated inflammation also relates to OWOB and decreased cognitive function. Thus, the experience of weight related stigma may exacerbate existing inflammation in individuals with OWOB, further impairing cognitive function. The present study seeks to expand our knowledge of these complex relationships, exploring the associations between weight status, eating behavior, cognitive function, sleep, and stigma. To do this, the study will utilize data from 2 groups: adolescents with normal weight and adolescents with OWOB. Adolescents in each group will complete two sleep conditions in a randomized order: adequate and restricted. Each sleep condition will be followed by a self-serve breakfast and completion of a cognitive battery. Prior to completing the sleep conditions, adolescents will participate in a baseline appointment during which they will complete a questionnaire regarding weight related stigma experiences. The investigators propose that cognitive function and sleep restriction may relate to adolescent weight status through the following mechanisms: 1) elevated adiposity will predict greater impairments in cognitive functioning, poorer nutritional intake, and greater food consumption, 2) sleep restriction will result in impaired cognitive functioning, poorer nutritional intake, and increased food consumption in all adolescents, 3) sleep restriction in adolescents with elevated adiposity will result in the greatest cognitive impairments, poorest nutritional intake, and greatest food consumption, and 4) decreased cognitive function will be associated with poorer nutritional intake and greater food consumption in all adolescents. The investigators also propose that stigma experiences relate to adolescent weight status through the following mechanisms: 1) heightened stigma experiences will predict impairments in cognitive functioning in all adolescents and 2) elevated adiposity will relate to greater stigma experiences and subsequently higher cognitive impairments, resulting in the worst outcomes for assessments of cognitive function .

Official Title
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Sleep and Stigma: Novel Moderators in the Relationship Between Weight Status and Cognitive Function

Conditions
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Obesity, Childhood, Overweight, Childhood

Intervention / Treatment
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* Behavioral: Restricted Sleep
* Behavioral: Adequate Sleep


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adolescent ages 14-19 Exclusion Criteria: age under 14 or over 19 sleep disorder use of medications which impact sleep learning disorder history of eating disorder recent weight changes >10 pounds in the last 1 month current feeding/eating difficulties scores on the food fussiness sub-scale of the Childhood Eating Behaviors Questionnaire above 4.5 (out of 5)

Ages Eligible for Study
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Minimum Age: 14 Years
Maximum Age: 19 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Non-Randomized
Intervention Model: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Adolescents with Normal Weight<br>This group will be comprised of 30 adolescents with normal weight (BMI equal to or greater than the 5th percentile but less than the 85th percentile). Participants will be asked to engage in the sleep manipulation intervention. | Behavioral: Restricted Sleep<br>* During the restricted sleep condition adolescents will sleep 4 hours ±1 hour (0100-0500). This condition will last 1 night.<br>Behavioral: Adequate Sleep<br>* During the adequate sleep condition adolescents will sleep 9 hours ±1 hour (2100- 0800). This condition will last 1 night.<br>|
| Experimental: Adolescents with Overweight or Obesity<br>This group will be comprised of 30 adolescents with overweight or obesity (BMI equal to or above the 85th percentile). Participants will be asked to engage in the sleep manipulation intervention. | Behavioral: Restricted Sleep<br>* During the restricted sleep condition adolescents will sleep 4 hours ±1 hour (0100-0500). This condition will last 1 night.<br>Behavioral: Adequate Sleep<br>* During the adequate sleep condition adolescents will sleep 9 hours ±1 hour (2100- 0800). This condition will last 1 night.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Objectively Measured Cognitive Function Composite Score After Sleep Restriction | Overall cognitive function score measured using the National Institute of Health Toolbox Cognition Battery. Scores reported as standard scores with an average normative score of 100 and standard deviation of 15. Higher standard scores indicate better performance. | Immediately after the sleep restricted intervention | 
| Objectively Measured Cognitive Function Composite Score After Adequate Sleep | Overall cognitive function score measured using the National Institute of Health Toolbox Cognition Battery. Scores reported as standard scores with an average normative score of 100 and standard deviation of 15. Higher standard scores indicate better performance. | Immediately after the adequate sleep intervention | 
| Objectively Measured Fluid Cognition Composite Score After Sleep Restriction | Executive function, attention, processing speed, and episodic and working memory measured using the National Institute of Health Toolbox Cognition Battery. Scores reported as standard scores with an average normative score of 100 and standard deviation of 15. Higher standard scores indicate better performance. | Immediately after the sleep restricted intervention | 
| Objectively Measured Fluid Cognition Composite Score After Adequate Sleep | Executive function, attention, processing speed, and episodic and working memory measured using the National Institute of Health Toolbox Cognition Battery. Scores reported as standard scores with an average normative score of 100 and standard deviation of 15. Higher standard scores indicate better performance. | Immediately after the adequate sleep intervention | 
| Objectively Measured Attention After Sleep Restriction | Measured using the Flanker Inhibitory Control and Attention subtest of the National Institute of Health Toolbox Cognition Battery. Scores reported as standard scores with an average normative score of 100 and standard deviation of 15. Higher standard scores indicate better performance. | Immediately after the sleep restricted intervention | 
| Objectively Measured Attention After Adequate Sleep | Measured using the Flanker Inhibitory Control and Attention subtest of the National Institute of Health Toolbox Cognition Battery. Scores reported as standard scores with an average normative score of 100 and standard deviation of 15. Higher standard scores indicate better performance. | Immediately after the adequate sleep intervention | 
| Objectively Measured Working Memory After Sleep Restriction | Measured using the List Sorting Working Memory subtest of the National Institute of Health Toolbox Cognition Battery. Scores reported as standard scores with an average normative score of 100 and standard deviation of 15. Higher standard scores indicate better performance. | Immediately after the sleep restricted intervention | 
| Objectively Measured Working Memory After Adequate Sleep | Measured using the List Sorting Working Memory subtest of the National Institute of Health Toolbox Cognition Battery. Scores reported as standard scores with an average normative score of 100 and standard deviation of 15. Higher standard scores indicate better performance. | Immediately after the adequate sleep intervention | 
| Objectively Measured Processing Speed After Sleep Restriction | Measured using the Pattern Comparison Processing Speed subtest of the National Institute of Health Toolbox Cognition Battery. Scores reported as standard scores with an average normative score of 100 and standard deviation of 15. Higher standard scores indicate better performance. | Immediately after the sleep restricted intervention | 
| Objectively Measured Processing Speed After Adequate Sleep | Measured using the Pattern Comparison Processing Speed subtest of the National Institute of Health Toolbox Cognition Battery. Scores reported as standard scores with an average normative score of 100 and standard deviation of 15. Higher standard scores indicate better performance. | Immediately after the adequate sleep intervention | 
| Objectively Measured Cognitive Flexibility After Sleep Restriction | Measured using the Dimensional Change Card Sort subtest of the National Institute of Health Toolbox Cognition Battery. Scores reported as standard scores with an average normative score of 100 and standard deviation of 15. Higher standard scores indicate better performance. | Immediately after the sleep restricted intervention | 
| Objectively Measured Cognitive Flexibility After Adequate Sleep | Measured using the Dimensional Change Card Sort subtest of the National Institute of Health Toolbox Cognition Battery. Scores reported as standard scores with an average normative score of 100 and standard deviation of 15. Higher standard scores indicate better performance. | Immediately after the adequate sleep intervention | 
| Objectively Measured Inhibition After Sleep Restriction | Measured using the Stroop Task | Immediately after the sleep restricted intervention | 
| Objectively Measured Inhibition After Adequate Sleep | Measured using the Stroop Task | Immediately after the adequate sleep intervention | 
| Objectively Measured Episodic Memory After Adequate Sleep | Measured using the Picture Sequence Memory subtest of the National Institute of Health Toolbox Cognition Battery. Scores reported as standard scores with an average normative score of 100 and standard deviation of 15. Higher standard scores indicate better performance. | Immediately after the adequate sleep intervention | 
| Objectively Measured Episodic Memory After Restricted Sleep | Measured using the Picture Sequence Memory subtest of the National Institute of Health Toolbox Cognition Battery. Scores reported as standard scores with an average normative score of 100 and standard deviation of 15. Higher standard scores indicate better performance. | Immediately after the restricted sleep intervention | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Subjectively Measured Behavior Regulation | Inhibition and self-monitoring measured using the Behavior Rating Inventory of Executive Function. Scores are given as T-scores and percentiles with higher values indicating greater impairment. | Baseline | 
| Subjectively Measured Emotional Regulation | Emotional control and shifting measured using the Behavior Rating Inventory of Executive Function. Scores are given as T-scores and percentiles with higher values indicating greater impairment. | Baseline | 
| Subjectively Measured Cognitive Regulation | Task completion, working memory, and planning/organizing measured using the Behavior Rating Inventory of Executive Function. Scores are given as T-scores and percentiles with higher values indicating greater impairment. | Baseline | 
| Subjectively Measured Global Executive Composite | Overall score on the Behavior Rating Inventory of Executive Function. Scores are given as T-scores and percentiles with higher values indicating greater impairment. | Baseline | 
| Food Consumption After Sleep Restriction | Participants will be given a self-serve breakfast of whole and processed foods. Foods will be weighed to the nearest 0.1g before and after the meal to determine the amount consumed. Overall macronutrient content of foods consumed will be recorded. | Immediately after the sleep restricted intervention | 
| Food Consumption After Adequate Sleep | Participants will be given a self-serve breakfast of whole and processed foods. Foods will be weighed to the nearest 0.1g before and after the meal to determine the amount consumed. Overall macronutrient content of foods consumed will be recorded. | Immediately after the adequate sleep intervention | 
| Stigma Experiences | Measured using the brief version of the Stigmatizing Situations Inventory. Composite scores range from 0-90, with higher scores indicating more frequent stigma experiences. | Baseline | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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sleep, stigma, cognitive function, nutrition