The relation between indoor air quality in a bedroom and sleep quality of ageing adults

Research on the effect of indoor air quality (IAQ) on sleep quality is limited. Furthermore, most research has been conducted with students. Therefore, the effect of IAQ (CO2 concentration as proxy) on the sleep quality of ageing adults was investigated. Twenty-two volunteers were studied during two periods of four consecutive nights. Each period at a different setting of a mechanical ventilation system (Low/High). IAQ was measured continuously. Indices of sleep quality were analyzed via actigraphy and questionnaires. Perceived IAQ was investigated as well. A significant difference in CO2 concentration was obtained for the two ventilation settings investigated. Objectively measured sleep quality, as well as subjective outcomes, did not differ when comparing both settings. At high setting, the perceived IAQ was improved. From the data gathered, it could be concluded that older people (>55 year) experienced more nightly awakenings, and a significantly better depth of sleep. Women judged the air quality significantly lower when compared to men.