Cognitive status changes based on time of day in nursing home patients with and without dementia.

Background: Changes in behavior and cognition have been observed with disruption of the circadian rhythm.

Methods: This study examined the effects of time of day (TOD) on administration of Mini-Mental State Examinations (MMSEs) in nursing home patients with dementia (patients) or functional psychiatric disorders (control), using repeated measures analyses of covariance (ANCOVAs).

Results: Controls (n = 34) scored significantly higher than patients (n = 38) on total MMSE and all subscales. Within the patients, men and women performed equally in the morning, but women performed marginally worse in the afternoon on total MMSE scores, orientation, and immediate recall and men performed significantly better in the afternoon. Within the control, no gender or time effects were detected.

Conclusion: Results indicate that TOD had no significant impact on cognitive status in patients with dementia or patients with other psychiatric illnesses. No changes in activity timings are recommended in nursing home patients with dementia.