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Increased frequency of retinopathy of prematurity over the last decade and significant regional differences
Gerd Holmström1, Kristina Tornqvist2, Abbas Al-Hawasi3
1Department of Neuroscience/ophthalmology, Uppsala University, Uppsala, Sweden.
Insights
Retinopathy of prematurity (ROP) incidence increased in Sweden from 2008-2015, with significant regional variations in ROP rates and treatment frequency. Changes in oxygen targets did not uniformly affect ROP treatment across all regions.
Area of Science:
- Ophthalmology
- Neonatology
- Public Health
Background:
- Retinopathy of prematurity (ROP) is a leading cause of childhood blindness in premature infants.
- While increased oxygen levels improve survival and reduce cerebral palsy, they are linked to a higher incidence of ROP.
Purpose of the Study:
- To evaluate national and regional incidences and treatment frequencies of ROP in Sweden.
- To assess the impact of updated oxygen saturation targets on ROP outcomes.
Main Methods:
- Utilized the Swedish national ROP register (SWEDROP) for data from 2008-2015 (n=5734).
- Analyzed ROP incidence and treatment rates before and after oxygen target changes in 2014 (85-89% to 91-95%).
Main Results:
- Overall ROP incidence increased significantly (p=0.003) during the study period, but treatment frequency did not significantly change.
- Significant regional disparities in ROP incidence and treatment were observed (p<0.001).
- One region showed a significant increase in treated ROP post-oxygen target change (OR: 2.24), with another showing a borderline increase (OR: 3.08).
Conclusions:
- The Swedish ROP register indicates a rising incidence of ROP over an 8-year period.
- Significant regional variations in ROP incidence and treatment frequency highlight the need for localized strategies.
Purpose:
Retinopathy of prematurity (ROP) causes childhood blindness globally in prematurely born infants. Although increased levels of oxygen supply lead to increased survival and reduced frequency of cerebral palsy, increased incidence of ROP is reported.
Methods:
With the help of a Swedish register for ROP, SWEDROP, national and regional incidences of ROP and frequencies of treatment were evaluated from 2008 to 2015 (n = 5734), as well as before and after targets of provided oxygen changed from 85-89% to 91-95% in 2014.
Results:
Retinopathy of prematurity (ROP) was found in 31.9% (1829/5734) of all infants with a gestational age (GA) of <31 weeks at birth and 5.7% of the infants (329/5734) had been treated for ROP. Analyses of the national data revealed an increased incidence of ROP during the 8-year study period (p = 0.003), but there was no significant increase in the frequency of treatment. There were significant differences between the seven health regions of Sweden, regarding both incidence of ROP and frequency of treatment (p < 0.001). Comparison of regional data before and after the new oxygen targets revealed a significant increase in treated ROP in one region [OR: 2.24 (CI: 1.11-4.49), p = 0.024] and a borderline increase in one other [OR: 3.08 (CI: 0.99-9.60), p = 0.052].
Conclusion:
The Swedish national ROP register revealed an increased incidence of ROP during an 8-year period and significant regional differences regarding the incidence of ROP and frequency of treatment.
