Factors predictive of serum cortisol in pediatric patients with acute physiological stress: a cohort study

Area of Science:

• Pediatric Endocrinology
• Clinical Chemistry
• Critical Care Medicine

Background:

• Cortisol measurement is vital for assessing adrenal function in stressed patients.
• Cortisol levels can be affected by numerous clinical variables, complicating interpretation.
• Identifying predictors of cortisol variability is essential for accurate clinical assessment in pediatric populations.

Purpose of the Study:

• To identify independent predictors of serum cortisol levels in pediatric patients experiencing acute physiological stress.
• To explore the association between various clinical factors and cortisol concentrations in critically ill children.

Main Methods:

• A prospective study involving 217 pediatric patients admitted to general or pediatric intensive care units.
• Serum cortisol levels were measured within 72 hours of admission.
• Multiple regression analysis using a mixed-effects model was employed to identify predictors of cortisol levels.

Main Results:

• A total of 397 samples were analyzed, with a median cortisol level of 375 nmol/L.
• Significant predictors of higher cortisol levels included elevated heart rate z-score, body temperature, and Pediatric Early Warning System score.
• Younger age (3-6 years), earlier sampling time (<4 hours from registration), and morning sampling (6-10 AM) were also associated with higher cortisol.

Conclusions:

• Heart rate z-score, body temperature, Pediatric Early Warning System score, age, elapsed time, and sampling time are independent predictors of cortisol levels in pediatric patients under acute physiological stress.
• These findings aid in the interpretation of cortisol measurements in critically ill children.
• Understanding these predictors can improve the clinical assessment of adrenal function in pediatric stress scenarios.