Twenty-four-hour rhythms of sleep-wake cycle and temperature in Alzheimer's disease.

The authors aimed to examine the difference in 24-hour rhythms of sleep-wake cycle and temperature between Alzheimer's disease (AD) patients and elderly comparison subjects. The continuous measuring of wrist activity and skin temperature was conducted for 96 hours in seven AD patients (age: 77.0 +/- 4.3) and 11 normal comparison subjects (age: 74.2 +/-5.2). The mean acrophases and amplitudes of the two rhythms in the AD group were not different from those in the comparison group. The mean phase difference between the two rhythms, however, was significantly lower in the AD group than in the comparison group.