Sleep and Circadian Rhythms in Survivors of Acute Respiratory Failure

Abstract

Background: Little is known about sleep and circadian rhythms in survivors of acute respiratory failure (ARF) after hospital discharge. Objectives: To examine sleep and rest-activity circadian rhythms in ARF survivors 3 months after hospital discharge, and to compare them with a community-dwelling population. Methods: Sleep diary, actigraphy data, and insomnia symptoms were collected in a pilot study of 14 ARF survivors. Rest-activity circadian rhythms were assessed with wrist actigraphy and sleep diary for 9 days, and were analyzed by cosinor and non-parametric circadian rhythm analysis. Results: All participants had remarkable actigraphic sleep fragmentation, 71.5% had subclinical or clinical insomnia symptoms. Compared to community-dwelling adults, this cohort had less stable rest-activity circadian rhythms (p < 0.001), and weaker circadian strength (p < 0.001). Conclusion: Insomnia and circadian disruption were common in ARF survivors. Sleep improvement and circadian rhythm regularity may be a promising approach to improve quality of life and daytime function after ARF.

Keywords: actigraphy; acute respiratory distress syndrome; circadian rhythm; critical illness; sleep.

Figure 1

Diagram illustrating four parameters of the oscillation from cosinor analysis: mesor (the estimated mean activity count of the fitted 24-h pattern), period (the duration of a full cycle), magnitude (mesor-to-peak difference, indicating robustness/strength of rhythm), and acrophase (the time of peak activity). Adapted from Cornelissen (28).