Older Is Colder: Temperature Range and Variation in Older People

Objectives: To ascertain body temperatures in older people. Design: Analysis of oral temperatures obtained from elderly subjects residing in the community and nursing home. Setting: A single nursing home, office setting, and community center. Participants: One hundred nursing home residents and 50 subjects residing in the community. Measurements: Three oral temperatures were measured in nursing home residents and once in community dwellers using an electronic digital thermometer. Results: The average age of subjects was 80.7. Temperatures ranged from 94.0°F to 99.6°F. In nursing home subjects, the 6 a.m. mean temperature was 97.3°F, 4 p.m. mean was 97.4°F, and 10 p.m. mean was 97.8°F. The single midday mean temperature in community dwellers was 97.7°F. Ninety‐seven of 100 (97%), 94 of 100 (94%), and 83 of 96 (86%) recordings were below 98.6°F in nursing home residents at 6 a.m., 4 p.m., and 10 p.m., respectively. Similarly, 45 of 50 (90%) community dwellers had midday temperatures below 98.6°F. Repeated‐measures analysis demonstrated an increase in temperature during the day. The increase was greatest in the youngest old, with no significant change in body temperature over the course of the day in the oldest old. Conclusion: Older subjects have mean oral body temperatures lower than 98.6°F. Relatively few even achieve this temperature. In nursing home residents, the oldest were coldest and failed to demonstrate a diurnal rise in body temperature.