Outcomes of extremely premature infants related to their peak serum bilirubin concentrations and exposure to phototherapy

Objectives. To analyze,in extremely low birth weight infants, associations between peak bilirubin concentration and evidence of brain damage, and betw een peak bilirubin concentration and blindness attributable to retinopathy of prematurity. Methods. Retrospective study of 128 infants of less than or equal to 800 g birth weight and less than or equal to 27 weeks gestation born between 1980 and 1989 and discharged from a tertiary neonatal intensive care unit. Afte r screening analyses, multivariable analyses were conducted to identify ass ociations between blindness and peak bilirubin concentration (dichotomized at different levels to create 3 binary variables), and between severe adver se neurodevelopmental outcome at 18 months postterm age and peak bilirubin levels. Results. Of 128 18-month survivors, 15 had severe visual loss attributable to retinopathy of prematurity, 21 had neurodevelopmental deficit, and 5 wer e deaf. Visual loss was significantly associated with low-peak serum biliru bin concentration (<9.4 mg/dL (<160 mu mol/L) versus greater than or equal to 9.4 mg/dL (odds ratio [OR] confidence interval [CII 4.48 [1.15-17.43])), low gestational age (OR [CII per week 1.95 [1.05-3.63]), and longer durati on of phototherapy (OR [CI] per 10 hours 1.17 [1.02-1.33]). The association of neurodevelopmental impairment with grades 3 and 4 intraventricular hemo rrhage was statistically significant (OR 5.39 [1.83-15.84]), but with high- peak serum bilirubin concentration greater than or equal to 11.7 mg/dL (gre ater than or equal to 200 mu mol/L), was not significant (OR 2.89 [0.87-9.5 3]). Conclusions. In these infants, prolonged phototherapy and low-peak serum bi lirubin concentrations were associated with severe visual loss attributable to retinopathy of prematurity. The findings should be interpreted with cau tion until the evidence is reinforced in other patient populations.