R. H. Fox

Body temperatures in the elderly: a national study of physiological, social, and environmental conditions.

Two large-scale surveys of body temperatures in elderly people living at home were carried out in the winter of 1972. Most of the homes visited were cold with room temperatures below the minimum recommended by the Department of Health. Deep body temperatures below 35·5°C were found in 10% of those studied, and the difference between the skin temperature and the core temperature was also reduced in this group. Such individuals are at risk of developing hypothermia since they show evidence of some degree of thermoregulatory failure. Further research is needed, but meanwhile there are practical measures that could be taken to reduce the risk of hypothermia in the elderly.

Accidental hypothermia and impaired temperature homoeostasis in the elderly.

A longitudinal study of the age-related decline in thermoregulatory capacity was made in 47 elderly people to try to identify those at risk from spontaneous hypothermia. During the winters of 1971-2 and 1975-6 environmental and body temperature profiles were obtained in the home, and thermoregulatory function was investigated by cooling and warming tests. Environmental temperature and socioeconomic conditions had not changed but the body core-shell temperature gradients were smaller in 1976, indicating progressive thermoregulatory impairment. People at risk of developing hypothermia also seem to have low resting peripheral blood flows, a nonconstrictor pattern of vasomotor response to cold, and a higher incidence of orthostatic hypotension.

Problem of the Old and the Cold

A pilot winter study of body temperatures using new measuring techniques was tested on 72 volunteers aged 65 or more living in Portsmouth. The body temperatures were related to their environmental temperature and living conditions. No case of serious hypothermia was found, but the study confirms that elderly people have lower body temperatures and suggests that the coldest individuals tended to be the least aware of discomfort from the cold; this may well place them “at risk” for developing hypothermia.

Hypothermia in a young man with an anterior hypothalamic lesion.

Abstract Tests of central thermoregulatory function in a young man suffering from repeated episodes of hypothermia revealed defects in the heat-conserving mechanisms of peripheral vasoconstriction and shivering. Serial electroencephalographs suggested a deep midline cerebral lesion, but tests of hypothalamic-pituitary axis metabolic functions were normal. Necropsy revealed a localised but severe degenerative lesion in the anterior hypothalamus. Body-temperature regulation should be tested early in the clinical investigation of patients with suspected lesions of the hypothalamic-pituitary region.

Diagnosis of accidental hypothermia of the elderly.

Abstract The diagnosis of accidental hypothermia depends on establishing the presence of a deep body temperature below 35°C (95°F). For this purpose mouth temperature is unreliable. The rectal measurement is reliable but unpopular. Its use is therefore frequently avoided in domiciliary practice, and as a result the diagnosis of hypothermia may be missed. Described here is an alternative technique based on the measurement of urine temperature in a specially designed urine-temperature bottle. Experiments in healthy volunteers exposed to a cool environment demonstrated that temperature measured in this way is closely correlated with rectal temperature.