Physiological responses and thermal sensations of the elderly in cold and hot environments

doi:10.1016/0306-4565(93)90059-3

Journal of Thermal Biology

Volume 18, Issues 5–6, December 1993, Pages 355-361

https://doi.org/10.1016/0306-4565(93)90059-3 Get rights and content

Abstract

1.
1. 10 elderly and 10 college-aged females served as subjects in cold and heat environments. The subjects changed into the standard clothing (0.63 clo), and stayed in the neutral environment (25°C) for 23 min, thereafter they were exposed to the cold (10°C) or hot (35°C) environment for 49 min.
2.
2. Then they returned to the neutral environment, and stayed there for 47 min. Oral temperature, skin temperatures at 10 sites, blood pressure and thermal sensation were measured during the experiments.
3.
3. In the cold environment, the elderly could not reduce heat loss by vasoconstriction as did young people, and their blood pressures increased more rapidly than in young people. In the hot environment, the elderly could not promote heat loss by vasodilation as did young people. Moreover, there is a delayed sensitivity to cold for the elderly. Therefore, in the houses of the elderly, it is important to have heating and cooling systems which also includes the areas where the people do not stay for a long period of time (e.g. toilet, passageways).

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Citation Excerpt :
Such insensitivity to thermal environments may cause heat-related illnesses and even mortality [15]. Studies have shown that heart rate, blood pressure, and oxygen saturation change dramatically in the elderly when there is an abrupt change in the ambient temperature [16,17]. It has been suggested that cooling and heating systems be installed in the elderly residential buildings (including bathrooms and corridors where the length of stay is short) to alleviate the discomfort of the elderly caused by unexpected temperature changes [16].
A field survey was performed using questionnaires and physical measurements to investigate the thermal environment characteristics of typical transition spaces in residential buildings for the elderly and their impacts on the elderly's thermal adaptation. Forty-two buildings in 17 elderly care facilities in the Shanghai area were investigated. A model was constructed to predict the relationship of the temperature difference between the transition space and indoor environments, considering the indoor thermal satisfaction of the elderly dwelling in Shanghai's elderly care facilities. The elderly's indoor thermal satisfaction improved the most when the difference in temperature between the transition space and indoor environment was 6 °C and 2 °C in the winter and summer, respectively. Given the thermal satisfaction and self-assessed health of the elderly, the ideal model for designing a transition space in an elderly care facility is to utilize a semi-open external corridor with the temperature/humidity constantly increasing/decreasing from outdoors, transition space, and to indoors. A transition space assists the elderly in temperature adaptation through activities such as sunbathing and exercising. As a result, thermal conditions of aged-friendly care facilities should be designed and spatially composed to fulfil the needs of the elderly inhabitants. The use of an appropriate spatial thermal distribution within these environments can direct the elderly's daily behavior, improve their physical and mental health, and provide a scientific basis for planning and designing senior living communities.

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View full text

Thermal physiology of the elderly and handicappedPhysiological responses and thermal sensations of the elderly in cold and hot environments

Abstract

Environment, temperature and death rates

Age Ageing

Hypothermia and thermal responsiveness in the elderly

Urban hypothermia: preferred temperature and thermal perception in old age

Br. Med. J.

Effects of age on body temperature and blood pressure in cold environments

Clin. Sci.

Physiological and behavioral responses of aged men to passive heating

J. Physiol., Lond.

Investigation on the relationship between the indoor thermal environment of houses in the winter and cerebral vascular accident (CVA)

Jap. J. Public Health

Metabolic responses of old people to a cold environment

J. appl. Physiol.

Thermal physiology of the elderly and handicapped
Physiological responses and thermal sensations of the elderly in cold and hot environments