Serum neutrophil-to-lymphocyte ratio in retinopathy of prematurity.

Purpose: To evaluate the relationship between serum neutrophil-to-lymphocyte ratio (NLR) and development of retinopathy of prematurity (ROP).

Methods: Infants with a gestational age of ≤32 week were screened for ROP. Complete blood cell, high-sensitivity C-reactive protein, and interleukin 6 levels of subjects were measured within the first 24 hours of life. The NLR was calculated by dividing neutrophil count by lymphocyte count. The association between other risk factors and the development of ROP were analyzed using univariate analysis and multivariate logistic regression analysis.

Results: A total of 100 infants were included: 80 with ROP and 20 without ROP. The NLR values differed significantly between the ROP group (median, 0.67; interquartile range, 0.38-1.09) and non-ROP group (median, 0.32; interquartile range, 0.22-0.79; P = 0.02). The lymphocyte count in the ROP group (4.01 ± 1.89) compared to that of the non-ROP group (5.69 ± 2.16) was significantly lower (P = 0.001). In multivariate analysis, lymphocyte count remained an independent predictor of ROP (OR = 0.599; 95% CI, 0.430-0.836; P = 0.003).

Conclusions: The NLR seems not to be an independent predictor of development of ROP. Lymphocyte count is inversely associated with ROP.