CIRCA-MED WP1 & WP3 - Circadian Rhythms in ICU Patients

Condition(s) studied

Investigational drug(s) / intervention(s)

Exposure to routine clinical parameters: These are the primary exposures and are used to detect oscillatory patterns and characterize circadian rhythms. They include heart rate, body temperature, blood pressure, blood glucose, and insulin.

Exposure to ICU clinical factors and treatments: These are secondary exposures that may influence circadian rhythms: illness severity (e.g., Sequential Organ Failure Assessment (SOFA) score), sedation levels, organ support therapies (e.g., ventilation, dialysis, Extracorporeal Membrane Oxygenation (ECMO)), and medications administered during ICU stay (e.g., sedatives, vasopressors, corticosteroids).

Exposure to critical illness-related conditions: These exposures represent complications that may be associated with circadian disruption: delirium, deep sedation, ICU-acquired muscle weakness, and post-intensive care syndrome.

Exposure to molecular and hormonal circadian markers: These exposures reflect biological clock function: clock gene expression (if available in some cases), and melatonin levels.

Exposure to metabolic changes related to critical illness: These exposures represent metabolic consequences of critical illness: insulin sensitivity, muscle atrophy, and critical illness myopathy or ICU-acquired weakness.

Study summary

The goal of this retrospective exploratory study is to examine how the body's natural day-and-night rhythms and oscillatory patterns behave in people who were treated in the Intensive Care Unit (ICU). The study uses routine clinical data that were already collected during and after the ICU stay, including post-discharge follow-up measurements (where available), such as heart rate, temperature, blood pressure, blood sugar, and insulin. The researchers want to learn whether these measurements show daily patterns and whether patients can be grouped based on their oscillatory profiles. The study also examines whether certain clinical factors such as illness severity scores, sedation levels, organ support treatments, or medications are associated with changes in these oscillatory rhythms. The team will explore whether conditions that can develop during or after critical illness, such as delirium, muscle weakness, or Post-Intensive Care Syndrome (PICS), are linked to disturbed physiological rhythms. Another goal is to test whether it is technically possible to show a patient's rhythm profile in real time using routine data from the ICU information system, evaluated retrospectively. Digital tools called "Chrono-Apps" will be developed to display rhythmic information and may help clinicians adjust lighting to patient needs.

Eligibility

Primary outcome measure(s)

• Characterization of circadian periodicities and classification of time-varying patterns based on routine clinical data — From ICU admission to ICU discharge or death, whichever comes first (expected average duration of 4 weeks).
  Assessment of periodicities and time-varying patterns in routine clinical parameters, including heart rate, body temperature, blood pressure, blood glucose, and insulin levels. Time-series analysis will be conducted to extract continuous metrics (amplitude, period, and phase). Based on these metrics, patients will be classified into distinct categorical groups according to their periodic oscillation profiles.

Trial sites (1)

More Charite University, Berlin, Germany trials in Germany