Experimental study on sleep quality affected by carbon dioxide concentration.

Area of Science:

• Environmental Science
• Sleep Medicine
• Human Physiology

Background:

• Indoor air quality, particularly carbon dioxide (CO2) levels, can influence human health and well-being.
• Previous research suggests potential links between elevated CO2 and cognitive function, but its specific impact on sleep quality requires further investigation.

Purpose of the Study:

• To comprehensively investigate the impact of varying indoor carbon dioxide (CO2) concentrations on objective and subjective sleep quality.
• To determine the dose-response relationship between CO2 levels and specific sleep parameters.
• To explore potential gender differences in sleep quality response to CO2 exposure.

Main Methods:

• Controlled environmental chamber study with three CO2 concentrations (800, 1900, 3000 ppm).
• 12 healthy participants (6 male, 6 female) monitored for 54 days.
• Sleep quality assessed using subjective questionnaires and objective physiological measures, including sleep onset latency (SOL) and slow-wave sleep (SWS).

Main Results:

• Sleep quality significantly decreased with increasing CO2 concentration, with scores at 3000 ppm being 80.8% of those at 800 ppm.
• A positive linear correlation was observed between CO2 concentration and SOL.
• A negative linear correlation was found between CO2 concentration and SWS.
• Men reported better subjective sleep quality, had longer SWS, and shorter SOL compared to women, with a significant gender difference noted at 800 ppm (P < .05).

Conclusions:

• Indoor CO2 concentrations significantly degrade sleep quality, affecting both subjective perception and physiological sleep architecture.
• Increased CO2 levels prolong the time taken to fall asleep (SOL) and reduce restorative slow-wave sleep (SWS).
• Men may exhibit greater resilience to the negative effects of CO2 on sleep compared to women, highlighting a potential gender-specific vulnerability.