Temporal patterns of negative and positive behavior among nursing home residents with Alzheimer's disease.

Although clinical observations suggest a late-day peak in disruptive behavior in persons with dementia, results from studies of temporal patterns of behavior are equivocal. This study used direct observation methods and systematic time sampling to examine temporal patterns of negative and positive behavior in 177 residents of 2 long-term care facilities with clinically diagnosed Alzheimer's disease (AD). The authors found small statistically significant diurnal variation in both negative and positive behavior, characterized by a curvilinear pattern with a single peak. This pattern was unaffected by seasonal differences in length of day, severity of cognitive impairment, level of behavior, or sleep disturbances. Time when behavior peaked differed by type of behavior and by facility, and there was substantial heterogeneity in behavior patterns.