Disturbance in daily sleep/wake patterns in patients with cognitive impairment and decreased daily activity.
 The sleep/wake patterns of 121 chronically ill, mentally and physically handicapped patients were visually monitored hourly for 14 consecutive days.
 Four types of sleep/wake patterns were found.
 In order to investigate how cognitive and physical functions correlated with sleep disorders, patients were classified based on a scale of mental function and the grading of daily activity.
 The percent of total sleep hours and the sleep rating, showing disturbances in sleep/wake pattern, were evaluated.
 We found a high degree of individuality in sleep/wake patterns.
 Sleep disturbance was associated with daily activity as well as with cognitive impairment.
 This monitoring system provides medical personnel with valuable information for clinical management.
