ORIGINAL PAPER
The effect of air quality on sleep and cognitive performance in school children aged 10–12 years: a double-blinded, placebo-controlled, crossover trial
 
More details
Hide details
1
Aarhus University, Aarhus, Denmark (Department of Public Health, Section for Environment, Occupation and Health)
2
Aarhus University, Aarhus, Denmark (Department of Psychology and Behavioural Sciences)
3
Aarhus University, Aarhus, Denmark (Department of Chemistry)
4
Aarhus University, Aarhus, Denmark (Department of Public Health, Research Section of Biostatistics)
5
Technical University of Denmark, Lyngby, Denmark (Department of Environmental and Resource Engineering)
CORRESPONDING AUTHOR
Torben Sigsgaard   

Aarhus University, Department of Public Health, Section for Environment, Occupation and Health, Bartholin Allé 2, 8000 Aarhus C, Denmark
Online publication date: 2023-02-16
 
 
KEYWORDS
TOPICS
ABSTRACT
Objectives: To investigate the effect of CO2 during sleep on next-morning cognitive performance in young schoolchildren, the authors performed a double-blind fully balanced crossover placebo-controlled study. Material and Methods: The authors included 36 children aged 10–12 years in the climate chamber. The children slept at 21°C in 6 groups each at 3 different conditions separated by 7 days in a random order. Conditions were as follows: high ventilation with CO2 at 700 ppm, high ventilation with added pure CO2 at 2000–3000 ppm, and reduced ventilation with CO2 at 2–3000 ppm and bioeffluents. Children were subjected to a digital cognitive test battery (CANTAB) in the evening prior to sleep and on the next morning after breakfast. Sleep quality was monitored with wrist actigraphs. Results: There were no significant exposure effects on cognitive performance. Sleep efficiency was significantly lower at high ventilation with CO2 at 700 ppm which is considered to be a chance effect. No other effects were seen, and no relation between air quality during sleep and next-morning cognitive performance was observed in the children emitting an estimated 10 lCO2/h per child. Conclusions: No effect of CO2 during sleep was found on next day cognition. The children were awakened in the morning, and spent from 45–70 min in well-ventilated rooms before they were tested. Hence, it cannot be precluded that the children have benefitted from the good indoor air quality conditions before and during the testing period. The slightly better sleep efficiency during high CO2 concentrations might be a chance finding. Hence, replication is needed in actual bedrooms controlling for other external factors before any generalizations can be made.
eISSN:1896-494X
ISSN:1232-1087