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International variations and trends in the treatment for retinopathy of prematurity
Brian A Darlow1, Kei Lui2, Satoshi Kusuda3
1Australia and New Zealand Neonatal Network, Department of Paediatrics, University of Otago, Christchurch, New Zealand.
Insights
Retinopathy of prematurity (ROP) treatment rates varied significantly among high-income countries. Switzerland had lower treatment rates, while Japan had higher rates, indicating potential differences in care practices for preterm infants.
Area of Science:
- Neonatalogy
- Ophthalmology
- Public Health
Background:
- Retinopathy of prematurity (ROP) is a significant cause of visual impairment in preterm infants.
- Variations in ROP incidence and treatment exist globally, necessitating international comparative studies.
Purpose of the Study:
- To compare ROP rates and treatment patterns (laser or anti-VEGF) in preterm neonates across high-income countries.
- To identify variations in ROP management within the International Network for Evaluating Outcomes (iNeo) of neonates.
Main Methods:
- Retrospective cohort study of extremely preterm infants (<1500g) from 10 high-income countries (2007-2013).
- Analysis included pairwise comparisons of ROP treatment in survivors using Poisson and logistic regression.
- A composite outcome of death or ROP treatment was also compared.
Main Results:
- ROP screening occurred in 95% of survivors; ROP rates varied from 25.2% (Switzerland) to 91.0% (Japan).
- Overall ROP treatment rate was 24.9%, with significant country-specific variations (4.3% in Switzerland to 30.4% in Japan).
- Adjusted analyses showed lower ROP treatment risk in Switzerland and higher risk in Japan compared to other countries.
Conclusions:
- Significant international variations in ROP and its treatment were observed among iNeo member countries.
- An overall decline in ROP treatment was noted during the study period.
- Further research is needed to understand if these variations stem from differences in care practices, diagnostic criteria, or treatment thresholds.
Objective:
To compare the rates of retinopathy of prematurity (ROP) and treatment of ROP by laser or intravitreal anti-vascular endothelial growth factor among preterm neonates from high-income countries participating in the International Network for Evaluating Outcomes (iNeo) of neonates.
Methods:
A retrospective cohort study was conducted on extremely preterm infants weighing <1500 g at 240 to 276 weeks' gestation who were admitted to neonatal units in Australia/New Zealand, Canada, Finland, Israel, Japan, Spain, Sweden, Switzerland, Tuscany (Italy) and the UK between 2007 and 2013. Pairwise comparisons of ROP treatment in survivors between countries were evaluated by Poisson and multivariable logistic regression analyses after adjustment for confounders. A composite outcome of death or ROP treatment was compared between countries using logistic regression and standardised ratios.
Results:
Of 48 087 infants included in the analysis, 81.8% survived to 32 weeks postmenstrual age, and 95% of survivors were screened for ROP. Rates of any ROP ranged from 25.2% to 91.0% in Switzerland and Japan, respectively, among those examined. The overall rate of those receiving treatment was 24.9%, which varied from 4.3% to 30.4%. Adjusted risk ratios for ROP treatment were lower for Switzerland in all pairwise comparisons, whereas Japan displayed significantly higher ratios. Comparisons of the composite outcome between countries revealed similar, but less marked differences.
Conclusions:
Rates of any ROP and ROP treatment varied significantly between iNeo members, while an overall decline in ROP treatment was observed during the study period. It is unclear whether these variations represent differences in care practices, diagnosis and/or treatment thresholds.
