Refining the Apgar score cut-off point for newborns at risk

Area of Science:

• Neonatal research
• Pediatric mortality studies
• Public health

Background:

• The Apgar score is a standard assessment for newborns.
• Its predictive value for mortality, especially in low-mortality populations, requires nuanced understanding.
• Existing Apgar score thresholds for risk stratification lack robust evidence.

Purpose of the Study:

• To assess the predictive accuracy of Apgar scores for infant mortality in the first year of life.
• To evaluate Apgar score performance across different time points (1-min and 5-min) and infant groups (preterm and term).
• To challenge traditional Apgar score cut-offs used in clinical practice and research.

Main Methods:

• Utilized a large dataset (n=976,635) from the Swedish Medical Birth Registry (1990-1998).
• Included singleton live births without severe congenital malformations and gestational age >25 weeks.
• Employed Receiver Operating Characteristic (ROC) analysis to evaluate predictive power.

Main Results:

• Both 1-min and 5-min Apgar scores demonstrated strong discrimination for early mortality (Area Under ROC Curve >0.85).
• Recommended cut-off values: 1-min Apgar <8 for preterm and term infants, and 5-min Apgar <9 for preterm and term infants, to identify those at risk.
• Provided specific true-positive and false-positive rates for these cut-offs.

Conclusions:

• The study does not support the conventional Apgar score grouping (e.g., <4 or <7) for identifying at-risk infants.
• Data enables clinicians and researchers to define optimal, evidence-based Apgar score cut-offs.
• Customized cut-offs should consider neonatal care quality and resource availability, moving beyond historical values.