Recovery of Circadian Body Temperature in Aged Persons

Abstract

The human diurnal body temperature rhythm does not differ significantly between aged and young subjects; the amplitude and mean level, however, decrease with age. In order to know whether the core body temperature of disabled elderly persons was influenced by environmental factors, we measured the tympanic temperature of nursing home patients. In 4 of 10 tested patients, there was a statistically significant upward shift of the core body temperature within 1 month of admission (P < 0.05). This restoration of body temperature was observed to occur without any relationship to the season of admission. The amplitude of circadian body temperature did not change. There were significant seasonal variations in the diurnal body temperature range between summer and winter, especially between 0900 and 1100 hours in 5 persons with, and without, an upward shift of body temperature. The persons who recovered their body temperatures were thought to have been had lower-than-normal-body temperature for age prior to admission. Body temperature recovery after admission may have been caused by an improvement in energy intake and nutritional balance.