Temporal Dynamics Between Sleep and Physical Activity After Cardiac Surgery: A Cross-Lagged Panel Model

Area of Science:

• Cardiology
• Sleep Science
• Exercise Physiology

Background:

• Cardiac patients frequently experience sleep disturbances and reduced physical activity (PA) post-surgery.
• The reciprocal relationship between sleep and PA is established, but its temporal dynamics after cardiac surgery are not well understood.

Purpose of the Study:

• To investigate the temporal bidirectional relationship between sleep and PA in cardiac surgery patients.
• Utilize a cross-lagged panel model (CLPM) to analyze these dynamics.

Main Methods:

• Secondary analysis of a longitudinal study with 33 adult open-heart surgery patients.
• Collected 7 days of sleep and PA data using wrist-worn ActiGraphs.
• Employed CLPM to assess the temporal associations between sleep and PA variables.

Main Results:

• Participants had lower mean total sleep time (6.4 hours) than recommended but exceeded guidelines for moderate-to-vigorous PA.
• CLPM indicated unidirectional causation: improved sleep efficiency predicted greater energy expenditure and less sedentary time the following day.
• No significant predictive relationship was found from PA to subsequent sleep.

Conclusions:

• Enhancing sleep quality post-cardiac surgery may positively influence physical activity levels.
• Integrated strategies addressing both sleep and PA are crucial for cardiac rehabilitation programs.
• Further research with larger samples and diverse time points is needed to fully elucidate these complex interactions.