Variation in actigraphy-estimated rest-activity patterns by demographic factors.

Area of Science:

• Chronobiology
• Human Physiology
• Sleep Science

Background:

• Rest-activity patterns are key indicators of circadian rhythmicity in free-living individuals.
• Understanding variations in these patterns is crucial for assessing health implications.
• Previous research has explored circadian rhythms, but comprehensive analysis across diverse demographics is needed.

Purpose of the Study:

• To describe the distributions of rest-activity patterns in a sample of adults and children.
• To investigate how demographic variables (age, sex, race, education) influence these patterns.
• To provide a foundation for understanding the health implications of circadian rhythm variations.

Main Methods:

• Actigraphy was used to collect rest-activity data over 7 days and nights from 590 adults and 58 children.
• Cosinor analysis and nonparametric circadian rhythm analysis were employed to generate pattern metrics (MESOR, acrophase, magnitude, IS, IV, L5, M10, RA).
• Linear mixed-effects models were utilized to test for demographic differences in rest-activity patterns.

Main Results:

• Adolescents exhibited later activity periods (M10, L5), less regular patterns (lower IS, higher IV), and reduced amplitude compared to younger children.
• Mid-to-older adults showed earlier activity periods (M10, L5) and more regular patterns (higher IS, lower IV) than younger adults.
• Significant differences in rest-activity patterns were also observed based on sex, race, and education level.

Conclusions:

• Rest-activity patterns exhibit significant variation across the human lifespan.
• Demographic factors including age, sex, race, and education level are associated with distinct rest-activity patterns.
• Further research into these population-level variations is essential for understanding their health consequences.