Pathikan Dissaneevate, MD¹

Objective: To determine serum cortisol levels and their association with clinical outcomes in critically ill neonates admitted to the neonatal intensive care unit (NICU) at Hatyai Hospital. Clinical outcomes included neonatal mortality, length of hospital stay, and duration of ventilator use.

Materials and Methods: A retrospective cohort study was conducted between January 2022 and December 2024, involving 120 critically ill term neonates with conditions like neonatal sepsis with septic shock or respiratory failure. Patients were categorized by serum cortisol levels: Group 1 (cortisol of less than 18 μg/dL, 80 patients) and Group 2 (cortisol of 18 μg/dL or more, 40 patients). Baseline characteristics and clinical outcome data were collected. Statistical analysis compared the two groups and identified factors associated with mortality.

Results: Baseline characteristics were similar, except that Group 1 had a higher proportion of older neonates (age 2 to 20 days) (p=0.002). Mortality was higher in Group 2 (20.0%) compared to Group 1 (7.5%). Univariate analysis showed that age of 1 day or less, birth asphyxia, modified sick neonatal (MSN) score of 10 or less, use of more than two vasoactive inotropic drugs, and renal, electrolyte, and calcium abnormalities were significantly associated with death. Multivariate analysis revealed that age 2 to 20 days (adjusted OR 0.14, 95% CI 0.03 to 0.54, p=0.005) and MSN score of 10 or less (adjusted OR 10.31, 95% CI 1.87 to 56.87, p=0.007) were independently associated with mortality. Serum cortisol level was not a significant independent predictor of mortality (adjusted OR 2.19, 95% CI 0.57 to 8.33, p=0.251). There were no significant differences in ventilator duration, hospital length of stay, or NICU length of stay between the two groups. Time to NICU discharge did not differ significantly between infants with cortisol levels of less than 18 μg/dL and those with levels of 18 μg/dL or more (log-rank test, p=0.059).

Conclusion: Serum cortisol level was not an independent predictor of mortality or other clinical outcomes. MSN scores and young age may predict mortality outcome for critically ill neonate.

Received 25 November 2025 | Revised 19 January 2026 | Accepted 22 January 2026

DOI: 10.35755/jmedassocthai.2026.3.03790