The prognostic value of a risk score for necrotising enterocolitis

Necrotising enterocolitis is the most common severe acquired gastrointestinal disorder in the neonate yet there remains disagreement on predictive and prognostic factors. A previously published risk score purports to predict infants at greater risk of the disease. Fifty-nine cases and 59 matched controls were evaluated using data from the first 24 h after birth to determine the predictive and prognostic value of the score for necrotising enterocolitis. In simple models the risk score was significantly, but inversely, associated with necrotising enterocolitis, primarily due to greater respiratory problems among controls. This finding contrary to the premise is clarified by a significant interaction of the risk score with feeding variables. Odds ratios for the risk score varied at different levels of daily feeding increments. However, the risk score was not statistically significant in any models which controlled for feeding increment and the interaction. The risk score was significantly associated with mortality among necrotising enterocolitis cases. Though the score was not statistically significant when the outcome was disease stage or surgery, trends were in the expected direction. The data suggest that the risk score itself may not be an independent predictor of necrotising enterocolitis, but may indicate infants more vulnerable to other potential risk factors and, in addition, may be related to prognosis for those who do develop necrotising enterocolitis.