Assessment of bed temperature monitoring for detecting body movement during sleep: comparison with simultaneous video image recording and actigraphy

This study was designed to assess changes in bed temperature as an index of body movement. Changes in the temperature of the bed or mattress were used to estimate motility and number of awakenings, and total time in bed. Simultaneous temperature records, video image recordings and actigraphic data were obtained from 12 young adults for three consecutive nights. Significant agreement of time in bed and body movement among the three measurements was found. Intra-individual variability was low for time in bed. In a second study, 10 healthy elderly subjects used a temperature monitor at home for four consecutive nights. The time in bed was 8.1 h, a little longer than for the younger adults, but not markedly different. These studies show the potential usefulness of bed temperature monitoring as an index of sleep behaviour. Although the precise sleep index could not be observed, behaviour could be evaluated simply.