Risk Factors for Necrotizing Enterocolitis in Very Low Birth Weight Infants in a Tertiary Care Hospital

Background: Necrotizing enterocolitis (NEC) is a severe gastrointestinal condition correlated with increased morbidity and mortality in very low birth weight (VLBW) infants. The pathophysiology of NEC remains elusive due to its multifactorial nature. However, the identification and prevention of significant factors that cause NEC can improve the outcome of these neonates. Objective: To identify factors associated with the development of definite NEC, based on the modified Bell staging criteria stage II and III, in VLBW infants in a setting of tertiary care hospital. Materials and Methods: A single-center, case-control study was conducted in VLBW infants who were admitted to the neonatal intensive care unit (NICU) of Bhumibol Adulyadej Hospital, Bangkok, Thailand, between January 2008 and December 2022. Clinical data were collected from the electronic medical records. For each case of NEC, two controls without NEC, as non-NEC, were matched based on gestational age and period of hospitalization in the department. Data of mothers, infants, feeding patterns, and comorbidities prior to the diagnosis of NEC were analyzed. Results: There were 65 and 130 infants in the NEC and the non-NEC group, respectively. Infants in both groups had similar baseline characteristics. Multiple logistic regression showed the amount of human milk at the age of 14 days (adjusted OR 0.08, p<0.001) was a protective factor against NEC. Conversely, prolonged parenteral nutrition (PN) use (adjusted OR 4.81, p<0.001) and septic shock (adjusted OR 4.36, p=0.02) were risk factors for NEC. Conclusion: Early initiation of human milk may reduce the incidence of NEC. On the other hand, infants requiring extended PN and suffering septic shock were at an increased risk of developing NEC.