NPPB and retinopathy of prematurity: Czernik et al. first reported that urinary NT-proBNP was associated with ROP, and the AUCs of the ratio of urinary NT-proBNP concentration to creatinine (UNBCR) on the 14 and 28th days after birth for predicting severe ROP were 0.938 (P = 0.027) and 0.954 (P = 0.021), respectively (23).