Score for Neonatal Acute Physiology and Perinatal Extension II as a predictor of retinopathy of prematurity: study in 304 very-low-birth-weight preterm infants.

AIM

To evaluate the use of the Score for Neonatal Acute Physiology and Perinatal Extension (SNAPPE-II) at admission to predict the development of retinopathy of prematurity (ROP) among very-low-birth-weight preterm babies.

METHODS

A prospective cohort study included 304 infants screened for ROP from July 2004 to October 2007. The main outcomes were the development of any stage ROP and severe ROP. The main variable was the SNAPPE-II obtained at admission. Seventeen risk factors for ROP were studied by univariate analysis (chi(2) and Student's t test). A simple descriptive analysis was used for the SNAPPE-II (mean, median, standard deviation and interquartile range: p25-p75). Logistic regression and receiver-operating characteristic (ROC) curve were calculated for SNAPPE-II. Ophthalmological examinations started at the 6th week of life and were repeated until the 45th week of corrected gestational age (GA).

RESULTS

The mean GA and mean birth weight of the whole cohort were 30.3 weeks (+/-2.2) and 1,209.2 g (+/-277.7), respectively. The median SNAPPE-II among non-ROP and ROP patients were 6.0 and 15.0, respectively (p = 0.001). When compared with severe ROP patients (25.0) there was also a significant difference (p = 0.003). After logistic regression, the SNAPPE-II adjusted odds ratio for ROP was 1.024. The area under the ROC curve was 0.62 (95% confidence interval: 0.55-0.70, p < 0.001). The best discriminative cutoff value was 8.5 (sensitivity: 68%; specificity: 54%; positive predictive value: 37.3%; negative predictive value: 80.6%).

CONCLUSIONS

The SNAPPE-II values at admission were significantly higher among babies with ROP, suggesting a positive association between higher scores with the development of ROP, but after adjusted logistic regression and ROC curve results, the SNAPPE-II scores at admission did not enhance the assessment of risk for ROP.