Daily sleep patterns observed among institutionalized elderly residents.

The sleep/wake patterns of 16 institutionalized demented women were visually monitored hourly for 14 consecutive days. Individual mean total sleep time varied markedly from 5.0 to 12.1 hours per 24 hours. Unexpectedly, amounts of day sleep and night sleep correlated positively, suggesting a general sleep tendency manifested throughout the 24-hour day. Consistent individual sleep patterns and high inter-day correlations were found. A high degree of individuality in the sleep/wake patterns was also found, contrary to expectations that elderly obtain less sleep than others. Night sleep in the institutionalized elderly was not lessened by daytime sleep. Visual monitoring of sleep/wake patterns generated reliable data.