Are Cognition and Sleep Affected by Exposure to Carbon Dioxide and Bio Effluents During Sleep?

Danish: Projekt God-Nat. Et Studie af søvnmiljøets Betydning for børns indlæringsevne English: Good Night: A Study of the Impact of the Sleep Environment on Learning in Children

The aim of the project is to examine whether children's sleep and cognition are affected by exposure to CO2 and other bio effluents during sleep. The participants of the study are 36 children recruited from local schools in Aarhus, Denmark.

The study takes place in the climate chambers at the Department of Public Health, Aarhus University. These chambers allow for experimental testing on humans with advanced exposure generation while avoiding contamination from other sources and controlling temperature, humidity, noise, odor, and light.

The children will be sleeping in the chambers under three different conditions:

• One night of good ventilation with a CO2 level of maximum 800 ppm
• One night of good ventilation with high levels of CO2 (3,000 ppm)
• One night of poor ventilation with high concentrations of CO2 (3000 ppm) and other bio effluents.

The study is a within-group design, and groups of six children will be sleeping in the chambers for three nights (separated by seven days). The different groups of children are exposed to the conditions in a randomized order. The study is double-blinded (of security reasons the persons responsible for CO2 concentrations in the chambers are not blinded).

The study takes place on schools nights. The children arrive at 6 pm and leave for school the morning after. In the evening the children are tested for approximately 30-40 minutes to measure their cognitive performance using CANTAB (Cambridge Neuropsychological Test Automated Battery) on iPads. After completing the test, dinner is served and the children have some spare time before going to bed. During night, the quality of sleep (awake time and different sleep stages) will be monitored using Fitbit devices. Sleep quality will also be evaluated using a short sleep questionnaire. The next morning the cognitive performance of the children will be tested again using CANTAB before the children leave for school.

Our primary hypothesis is that children will perform worse on the cognitive test when exposed to high levels of CO2 and other bio effluents than compared to low levels of CO2 and bio effluents in a well-ventilated room. In addition to that our secondary hypotheses are:

• Children will perform worse on the cognitive test when exposed to high levels of CO2 and other bio effluents than compared to CO2 alone.
• Children will sleep less well in an environment with poor ventilation and high levels of CO2 and other bio effluents compared to sleeping in a well-ventilated room with low levels of CO2.
• Children will sleep less well in an environment with poor ventilation and high levels of CO2 and other bio effluents compared to sleeping in a room with high levels of CO2 alone.
• Children will sleep less well and perform worse on the cognitive test when exposed to high levels of CO2 compared to low levels of CO2.

Study Overview

• Status: Completed
• Conditions: Sleep; Environmental Exposure; Cognitive Impairment, Mild
• Intervention / Treatment: Other: Good ventilation; Other: Ventilation CO2; Other: Poor Ventilation

• Study Type: Interventional
• Enrollment (Actual): 36
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Denmark
  • Aarhus, Denmark, DK-8000
    • Aarhus University, Department of Public Health, Section for Environment, Occupation and Health

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 10 years to 12 years (Child)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Healthy children or children with a well-treated chronic disease not interfering with cognition and sleep quality
• Being able to accomplish a CANTAB test
• Completed questionnaires of sleep patterns

Exclusion Criteria:

• Unable to spend three nights (separated by seven days) in the climate chambers
• Conditions that prevent safe access to the chambers such as claustrophobia

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Quadruple

Number of Arms

6

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Other: Group 1; One night of good ventilation with a CO2 level of maximum 800 ppm; One night of good ventilation with high levels of CO2 (3000 ppm); One night of poor ventilation with high concentrations of CO2 (3000 ppm) and other bio effluents (The order of the three conditions are randomized)	Other: Good ventilation; Good ventilation with a low concentration of CO2; Other: Ventilation CO2; CO2 High and Good ventilation; Other: Poor Ventilation; Poor ventilation with high concentrations of CO2 and bio effluents
Other: Group 2; One night of good ventilation with a CO2 level of maximum 800 ppm; One night of good ventilation with high levels of CO2 (3000 ppm); One night of poor ventilation with high concentrations of CO2 (3000 ppm) and other bio effluents (The order of the three conditions are randomized)	Other: Good ventilation; Good ventilation with a low concentration of CO2; Other: Ventilation CO2; CO2 High and Good ventilation; Other: Poor Ventilation; Poor ventilation with high concentrations of CO2 and bio effluents
Other: Group 3; One night of good ventilation with High CO2 level of maximum 800 ppm; One night of good ventilation with high levels of CO2 (3000 ppm); One night of poor ventilation with high concentrations of CO2 (3000 ppm) and other bio effluents (The order of the three conditions are randomized)	Other: Good ventilation; Good ventilation with a low concentration of CO2; Other: Ventilation CO2; CO2 High and Good ventilation; Other: Poor Ventilation; Poor ventilation with high concentrations of CO2 and bio effluents
Other: Group 4; One night of good ventilation with a CO2 level of maximum 800 ppm; One night of good ventilation with high levels of CO2 (3000 ppm); One night of poor ventilation with high concentrations of CO2 (3000 ppm) and other bio effluents (The order of the three conditions are randomized)	Other: Good ventilation; Good ventilation with a low concentration of CO2; Other: Ventilation CO2; CO2 High and Good ventilation; Other: Poor Ventilation; Poor ventilation with high concentrations of CO2 and bio effluents
Other: Group 5; One night of good ventilation with a CO2 level of maximum 800 ppm; One night of good ventilation with high levels of CO2 (3000 ppm); One night of poor ventilation with high concentrations of CO2 (3000 ppm) and other bio effluents (The order of the three conditions are randomized)	Other: Good ventilation; Good ventilation with a low concentration of CO2; Other: Ventilation CO2; CO2 High and Good ventilation; Other: Poor Ventilation; Poor ventilation with high concentrations of CO2 and bio effluents
Other: Group 6; One night of good ventilation with a CO2 level of maximum 800 ppm; One night of good ventilation with high levels of CO2 (3000 ppm); One night of poor ventilation with high concentrations of CO2 (3000 ppm) and other bio effluents (The order of the three conditions are randomized)	Other: Good ventilation; Good ventilation with a low concentration of CO2; Other: Ventilation CO2; CO2 High and Good ventilation; Other: Poor Ventilation; Poor ventilation with high concentrations of CO2 and bio effluents

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Reaction time (Simple)	Reaction time in milliseconds. Outcome from CANTAB RTI Simple.	10 hours post start of exposure

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
CANTAB global composite score	CANTAB global composite score = outcomes from CANTAB transformed into a global composite score.	10 hours post start of exposure
Reaction Time (Five-Choice)	Reaction time in milliseconds. Outcome from CANTAB RTI Five-Choice.	10 hours post start of exposure
Sleep efficiency	Sleep efficiency = Percentage of time in bed spent sleeping.	Sleep measured for 9 hours during exposure in bed from 9 pm to 6 am.

Collaborators and Investigators

• Sponsor: University of Aarhus
• Investigators: Principal Investigator: Torben Sigsgaard, Department of Public Health - Institute of Environmental and Occupational Medicine, Aarhus University

Study record dates

Study Major Dates

• Study Start (Actual): January 23, 2018
• Primary Completion (Actual): June 22, 2018
• Study Completion (Actual): June 22, 2018

Study Registration Dates

• First Submitted: May 16, 2018
• First Submitted That Met QC Criteria: June 14, 2018
• First Posted (Actual): June 15, 2018

Study Record Updates

• Last Update Posted (Actual): October 11, 2018
• Last Update Submitted That Met QC Criteria: October 10, 2018
• Last Verified: May 1, 2018

More Information

Terms related to this study

• Keywords: sleep; cognition; carbon dioxide; bio effluents
• Additional Relevant MeSH Terms: Mental Disorders; Neurocognitive Disorders; Cognition Disorders; Cognitive Dysfunction
• Other Study ID Numbers: 111017

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No