Analysis of influencing factors for progression from type 2 to type 1 in retinopathy of prematurity

Objective To investigate factors associated with the progression of Retinopathy of Prematurity(ROP). Methods A retrospective analysis was performed on 148 ROP infants. All cases were classified into type 1 and type 2 ROP according to the ETROP criteria, and those progressing from type 2 to type 1 were defined as progressive type (prog-type). Intergroup differences and relevant factors for prog-type were analyzed. Results Among the 148 infants with ROP, 31 (20.9%) were type 1 ROP, 91 (61.5%) were type 2 ROP, and 26 (17.6%) were prog-type. Univariate analyses revealed significant differences among the three groups in gestational age (GA), birth weight(BW), delivery mode, 5-min Apgar score, hood/nasal cannula oxygen therapy(HH/MNCO) duration, non-invasive ventilation(NIV) duration, and presence of bronchopulmonary dysplasia(BPD) (all P < 0.05). The prog-type group had lower GA and BW, longer NIV duration and higher BPD rate. Significant differences in 5-min Apgar score and BPD existed between prog-type and type 2 ( P < 0.05). HH/MNCO duration differed significantly between type 1 vs. type 2 and type 1 vs. prog-type ( P < 0.05). Prog-type was most frequent in infants with GA of 27–32 weeks. In cesarean section (C-section) infants, the proportion of prog-type (12.8%) was significantly lower than that of type 1 (21.4%), while type 2 (65.8%) was significantly higher than type 1 (both P < 0.05). Type 2 was more common in the GA ≥ 33 weeks subgroup ( P < 0.05). Multinomial Logistic regression identified GA ( OR = 0.592, 95% CI = 0.456–0.768, P < 0.001) and HH/MNCO duration ( OR = 0.960, 95% CI = 0.925–0.996, P = 0.029) as independently associated with prog-type, and HH/MNCO duration ( OR = 0.954, 95% CI = 0.918–0.992, P = 0.016) as independently associated with type 1 ROP (all P < 0.05). Conclusion Different ROP groups exhibit distinct clinical characteristics. Lower GA, low BW, prolonged NIV and BPD were correlated with prog-type. Among C-section infants, prog-type was less common than type 1, whereas type 2 was more common than type 1. After multinomial adjustment, GA and HH/MNCO duration remained independently associated with prog-type, which may help clinical risk assessment and individualized intervention.