Subjective memory complaints in an elderly population with poor sleep quality

Area of Science:

• Gerontology
• Sleep Medicine
• Cognitive Neuroscience

Background:

• The relationship between sleep disturbances and cognitive decline in elderly populations remains debated.
• Subjective sleep quality is a key factor to consider in cognitive health assessments.

Purpose of the Study:

• To investigate the association between subjective sleep quality and cognitive function in Korean elderly individuals.
• To differentiate the impact of poor sleep on objective cognitive measures versus subjective memory complaints.

Main Methods:

• Analysis of 459 community-dwelling elderly subjects, with 352 selected based on absence of depression or neurological disorders.
• Cognitive function assessed using the Korean version of the Consortium to Establish a Registry for Alzheimer's Disease Neuropsychological Battery (CERAD-KN).
• Subjective sleep quality categorized using the Pittsburgh Sleep Quality Index into 'good' and 'poor' sleepers; subjective memory complaints measured by SMCQ.

Main Results:

• Poor sleepers reported more depressive symptoms and higher subjective memory complaints compared to good sleepers.
• No significant differences were found in objective cognitive assessments (CERAD-KN) between good and poor sleepers.
• Regression analysis indicated that depressive symptoms and subjective sleep quality were associated with subjective memory complaints (p < 0.001 and p = 0.005, respectively).

Conclusions:

• In elderly individuals without depression, poor sleep quality correlates with subjective memory complaints but not with objective cognitive impairment.
• Subjective memory complaints may precede the development of cognitive disorders, highlighting the importance of managing sleep quality.
• Adequate control of poor sleep quality is recommended for maintaining cognitive health in the elderly.