Ten-year changes in risk factors for requiring treatment of retinopathy of prematurity in extremely low birth weight infants: a multicenter study in Tokyo.

PURPOSE: To investigate 10-year changes in risk factors associated with treatment required for retinopathy of prematurity (ROP) in extremely low birth weight infants.

STUDY

DESIGN

Retrospective cohort study.

METHODS

Data for extremely low birth weight infants born in 2011 (Group 1) and those born in 2020-2021 (Group 2) were extracted from the Neonatal Research Network of Japan, with a total of 564 cases. The frequency of ROP treatment-related risk factors and results of multivariate analyses were compared between the two groups. Missing data in covariates were handled using multiple imputation.

RESULTS

Group 2 had a significantly lower birth weight (p=0.038), gestational age (p=0.037), and Apgar scores (p<0.001), than Group 1. The frequencies of resuscitation with intubation (p=0.030), oxygen therapy beyond 36 weeks' postmenstrual age (p<0.001), chronic lung disease (p=0.012), gastrointestinal perforation (p=0.030), and red blood cell transfusion (p=0.018) were higher in Group 2 than in Group 1. However, the incidence and treatment rate of ROP decreased over time. The multivariate analysis shows that mechanical ventilation for 60 days or more is a strong independent risk factor for ROP treatment in Group 1, but this effect disappeared in Group 2.

CONCLUSION

Birth weight and gestational age of extremely low birth weight infants born in Tokyo have decreased significantly compared with 10 years previously, and the severity of ROP has not increased. Advances in respiratory management may have contributed to reducing the risk of developing severe ROP.