Greater night-to-night variability in sleep discrepancy among older adults with a sleep complaint compared to noncomplaining older adults.

Research in younger adults suggests sleep discrepancy (objective/subjective measurement difference) is a consistent pattern that primarily occurs within individuals with insomnia. To examine whether older adults exhibit a similar pattern, this study compared night-to-night inconsistency in sleep discrepancy between older adults with and without sleep complaints. Older adults (N = 103; mean age = 72.81, SD = 7.12) wore an Actiwatch-L® (24 hr per day) and concurrently completed sleep diaries for 14 days. Sleep discrepancy = diary (sleep onset latency [SOL] or wake [time] after sleep onset [WASO]) - actigraphy (SOL or WASO). Both groups exhibited sleep discrepancy, but complainers exhibited significantly more night-to-night variability. Sleep discrepancy was a variable behavior that was not limited to insomnia, but instead manifested by degree throughout our older sample. Greater attention to variability in sleep research and clinical practice is warranted.