Indoor Microclimate and health in Vulnerable Older adults

There are few studies of indoor microclimate in geographical areas in subtropical as well as humid environments. During the summer period from May to October in 2024, vulnerable older adults in two districts of Hong Kong received home visits by two non-government organizations with the objective of determining whether the health impact of hot weather may be mitigated by raising health literacy relating to various preventive measures, home modification, distribution of cooling resources, and identification of heat-related illnesses and symptoms. A thermo-hygrometer was given to each participant to be placed at home for the monitoring of indoor temperature and humidity, the combined effect expressed as the humidex value. Information was collected relating to physical and mental health. Blood pressure and pulse rate were also measured during the visit. Features of the living accommodation were also recorded. No correlation between indoor humidex with thermal comfort or other health indicators was observed, with the exception of a weak negative correlation with diastolic blood pressure (r=-0.112, p=0.038, n=343), and a positive correlation with pulse rate (r=0.112, p=0.038, n=343). Seventy-eight percent (271/346) of flats had lower humidex indoors compared with outdoors. Sixty-three percent of the latter were public housing compared with privately owned flats, while flats with window orientation facing East and West had higher indoor humidex compared with other orientations. These findings inform mitigation strategies for the health impact of heat on vulnerable older population, that takes into account indoor microclimate and housing physical characteristics.

Keywords: Temperature, Humidity, Older Adults, Frailty, Building Characteristics.